"Don't study, don't know - Studying you will know!" NGUYEN TRUNG HOA Giao an Vt liu xy dng Trang 1 CHNG I TlNH LHRT LU LT LUR VRT LlEU XRT 0UNU . CAC 1NH CH1 v1 L CHU U CUA v1 L|U X DUNG * Nhcm coc fnh chf ||n quon dn cu foc bon fhn vf ||u |. KH| LUONG k|NG: . Kho| n|m: - Khi lng ring la khi lng cua mt n v th tch vt liu trang thai hoan toanc(khngcolrng)saukhicsykhnhit105oC110oCnkhi lng khng i.- Ky hiu a2. Cng fhuc fnh: Khi lng ring c tnh theo cng thc sau: aaVkG= ; g/cm m3 ... khVa -th tch hoan toan c cua mu th nghim 3. Coch a khac nhau. hng co dang hnh hoc xac nh: Phng phap vt liu chim ch cht lo0,2mm, Cn xac nh Gk, dung phng m ch cht long xac nh Va.. ngc vao thanh phn cu tao va cu truc vi m cuakhi lng ring c ly bng khi lng ring trung 3, kg/l, t/ trong o: Gk - khi lng mu th nghim trong trang thai h xoc d|nh: Tuy theo tng loai vt liu ma co nhng phng phap xac na. Vt liu c coi nh hoan toan c chc: thep, knh...- i vi mu co dang hnh hoc xac nh:Phng phap cn o bnh thng. - i vi mu kng xac nh Va. b. Vt liu khng hoan toan c chc: gach, a, btng, va . . . - Nghin nho mu vt liu n mc nho hn phap vt liu chi4 ho: - Khi lng ring cua vt liu ch phu thu no nn bin ng trong mt pham vi nho . - Dung tnh toan cp phi vt liu hn hp, mt s ch tiu vt ly khac ... - i vi vt liu hn hp, bnh xac nh theo cng thc sau: n nn hhaG G GG G G+ + ++ + +=......2 12 1 vt liu thng gp : 2 1- Khi lng ring a cua mt s loai a thin nhin : 2,5 3 g/cm3Giao an Vt liu xy dng Trang 2 Gach ngoi t set nung : 2,6 2,7 g/cm3

Vt liu hu c (g, bitum, cht deo, v.v...): 0,9 1,6 g/cm3

G 1H 1CH: Kho| tch: la khi lng cua mt n v th tch vt liu trang thai t thai t nhin sau khi c sy kh nhit 105oC 110oC n khi lng khng i. ng cuamt n v th tch vt liu dang hat i rac ng thai t nhin. Ky hiu ox, oddXimng2,9 3,2 g/cm3Btng nng : 2,5 2,6 g/cm3

||. KH| LUON.n|m: - Khi lng thnhin (k ca l rng). Ky hiu otn, oW-Khilngthtchtiuchun:lakhilngcuamtnvthtchvtliu trang Ky hiu otc, o- Khi lng th tch xp: la khi lrc ng tra

2. Cng fhuc fnh: tnooVG= ( g/cm3, kg/l, t/m3, ...) koktcoG=( g/cmV3, ...) 3, kg/l, t/mthungthung trong VL xVGo= ( g/cm3, kg/l, t/m3, ...) trong o: Gtn , G n G- khi lng mu th nghim trong trang thai kh Votn - th tch cua mu th nghim trang thai t nhinh nghim trang thai khPhng phap cn o bnh thng. t liu dang hat ri rac: xac nh khi lng th tch xpng ong G.W -khi lng mu th nghim trang thai t nhik

Vok- th tch cua mu t 3. Coch xoc d|nh : a. Vt liu co dang hnh hoc xac nh: b. Vt liu khng co dang hnh hoc xac nh: Phngphapvtliuchimchchtlong:bocparafinhocngmmubaohoa nc. c. VPhngphapng:ngvtliuvaomtthungongcodungtchbit trc mt cao nht nh. Cnkhi lng vt liu co trong thuGiao an Vt liu xy dng Trang 3 4. ngo th anh gia s b mt s tnh cht cua vt liu nh c tr s t liu, kho bai hay tnh cp phi - Khi in i trong pham vi rt ln. - Khi u thng gp : + a thin nhin loai c chc: 2,6 2,8 g/cm3i t set nung : 1,3 1,9 g/cm3

tng nng : 1,8 2,5 g/cm3 . Kho| gia phn th tch hoan toan c so vi th ch t nhin cua mu vt liu. c c ky hiu , thng tnh bng %. y l gia phn th tch rng so vi th tch t nhin cua mu vt liu. iu r, th nbng % 2. Cng fhucfnh: = ho: - Khi lng th tch phu thuc vao kt cu ni b ban thn vt liu, khi lng th tch xp phu thuc vao kch thc hat va s sp xp gia cac hat. - Bit khi lng th tch ta c, rng, cng , hut nc, h s truyn nhit cua vt liu, v.v... Ngoai ra, to, ox ta co th tnh toan d tru c phng tin vn chuyn vcua vt liu hn hp. lng th tch cua cac loai vt liu xy dng b lng th tch o cua mt s loai vt li+ Gach ngo+ B|||. C , kNG: n|m: c hay mt cua vt liu la ty st rng la t rng c ky h ng t h% 100 oaVV=% 100 % 100/akoG V / = okaG V % 100 =rVroV = == = 1 1 a o rV V V Vr o o oV V V% 100 1 =or atrong o: Va - phn th tch hoan toan c cua mu th nghim o - th tch t nhin cua mu th nghim3. PhLrngknlalrngringbit,khngthngvinhauvakhngthngvibn rng dn coc fnh chf khoccuo vf ||u: rng la mt ch tiu ky thut quan trong v no anh hng nhiu n cac tnh cht khac cua vt liu nh: cng , hut nc, kha nng truyn nhit, kha nng chng thm, chng b VVr - phn th tch rng cua mu th nghim n |co| | rng: ngoai. L rng h la l rng thng vi nhau va thng vi bn ngoai. 4. Anh huong cuo d dc, rng, fnh chf |- ng gia va chng n mon ... Giao an Vt liu xy dng Trang 4 * Nhcm coc fnh chf ||n quon dn m| fruong nuoc |v. M: . Kho| n|m: l nc co t nhin trong vt liu trang thai t nhin tai thi im th nghim2. Cnn trong mu vt liu ai kh. m la ty . Ky hiu W. g fhuc fnh : m c tnh bng ty l phn trm gia khi lng nc co t nhi thi im th nghimso vi khi lng mu vt liu trang th% 100 % 100 = =kvlkvltnvlkvltnnGG GGGWGvlk-_khi lng mu th nghim trang thai kh d|nh: hn cua h o ni b ua vt liu va ban cht a nc hay ky nc cua no. m hoc la khi m cua vt liu thay i th mt s tnh cht cua hay i theo nh: cng , kha nng dn nhit va dn in, th tch ... . HU1 NUOC: hut nc theo khi lng: la ty s phn trm gia khi lng nc co trong vt ho hi lng vt liu trong o :Gvltn- khi lng mu th nghim trang thai t nhin 3. Coch xoc-Cnmutrangthaitnhintaithiimthngim.Sykhmunkhi lng khng i. 4. ngho: - m la ai lng thay i lin tuc tuy thuc iu kin nhit va m mi trng, vt liu co th hut m hoc nha m tuy theo s chnh lch gia ap sut ring pi nc trong khng kh va trong vt liu. m cung phu thuc vao cu tac- Khi vt liu b vt liu cung t- Bit m cua v t liu iu chnh lng dung vt liu cho hp ly. v. Kho| n|m: hutnclakhanngvtliuhutvaginctrongcaclrngiukin nhit va ap sut thng (p = 1atmva to = 20 5oC ). 2. Cng fhuc fnh: liu khi c baoa trong iu kin nhit va ap sut thng so vi k trang thai kh. Ky hiu Hp , xac nh theo cng thc sau: % 100 % 100 = =kvlkvlbhvlkvlbhnpGG GGGHtrong o :Gvlbh -khi lng mu th nghim a bao hoa nc k-khi lng mu th nghim khGvlGiao an Vt liu xy dng Trang 5 hutnct a heothtch:l tysphntrmgiathtchnccotrongvtliu khi c bao hoa trong iu kin nhit va ap sut thng so vi th tch t nhin cua i kh. Ky hiu Hv , xac nh theo cng thc sau:vt liu trang tha% 100/% 100 % 100 = = =kvlbhnbhnbhnG G G VH/kvl o an o an ovG V V V anp vH H =tco. Cocthng i vi mu co kch thc ln. . Coc yu f onh huong dn d huf nuoc vo y ngho: huc vao cu tao ban thn vt liu ( c, rng, tnh cht l c hay ky nc cua vt liu.it va dn in tng, th tch tng... |. nccaonhtcuavtliuiukin a sut. 2. Cn : a khi lng nc co trong t liu3 h xoc d|nh: - Phng phap ngm t t iu kin bnh -Phngphapngmmtlniukinbnhthngivimucokchthc be. 4- hut nc phu trng), ban cht a n- Khi vt liu b bao hoa nc th mt s tnh cht cua vt liu cung thay i theo nh: cng giam, kha nng dn nh v8AO HOANUOC:. Kho| n|m : baohoanclakhannghutvagi cng bc v nhit hocp g fhuc fnh bao hoa nc theo khi lng: la ty s phn trm givkhi c bao hoa trong iu kin cng bc so vi khi lng vt liu trang thai kh. Ky hiu Hpmax , xac nh theo cng thc sau: % 100 % 100max= =bhdbkcbvlbhdkcbnG G GkvlkvlkvlpG GHGvlbhkcb -khi lng mu th nghim a bao hoa nc kcb k -khi lng mu th nghim kh u u Hvmax , xac nh theo cng thc sau: trong o : Gvl bao hoa nc theo th tch: la ty s phn trm gia th tch nc co trong vt liukhicbaohoatrongiukincngbcsovithtchtnhincuavtlitrang thai kh. Ky hi% 100//% 100 % 100max = = =kvl o ankvlbhdkcbno an ovV V bhdkcbnbhdkcbnG VG G G VH antcop vH H =max max t liu khi c b ng cua vt liu. Ky hiu Cbh. H s bao hoa nc: la ty s phn trm gia th tch nc cha trong vao hoa iu kin cng bc so vi th tch l r% 100 % 100/% 100V V VCo r rbh/max = = =rH V V Vv obhdkcbnbhdkcbn Giao an Vt liu xy dng Trang 6 trong o : Hvmax - bao hoa nc theo th tch r- rng cua vt liu 3. CocmHg - Phng phap ngm trong nc nhit 100oC nh huong dn d boc hco nuoc vo y ngho: . Kho- Tnh thm la tnh cht cua vt liu cho nc thm qua chiu day cua no khi gia b ngg cho nc thm qua chiu ay cu no khi gianh lch v ap sut thuy tnh. h xoc d|nh: - Phng phap ngm mu trong iu kin ap sut khng kh la 20m 4. Coc yu f o- hut nc phu thuc vao cu tao ban thn vt liu ( c, rng, tnh cht l rng), ban cht a nc hay ky nc cua vt liu.- Khi vt liu b bao hoa nc th mt s tnh cht cua vt liu cung thay i theo nh: cng giam, kha nng dn nhit va dn in tng, th tch tng... v||. 1NH 1HM NUOC:| n|m: haimt i xng co s chnh lch v ap sut thuy tnh. - Tnh ch thm la kha nng cua vt liu ngn khnd ahai b mt i xng co s ch2. Coch xoc d|nh vo cng fhuc xoc d|nh:a. Tnh thm: anh gia tnh thm ta dung h s thm nc Ktn ) (2 1p p Fa VKntn =c thm qua mu vt liu; m3 t thuy tnh gia hai b mt i xng; m ct ncuvtliucochiuday1m,tit tnh ai b mt i xng la 1m ngi ta dung mac chng thm. Mac chng thm o ncha thm qua c mu n quy nh. ng hnh tru, khi: cac din rn ditrng.Aplcncbanupo,sautgitng thm p na cho n khi xut hin vt thm. trong o :Vn - th tch n a- chiu day thm cua mu vt liu; m F- tit din chu thm; m2 - thi gian thm; h (p1- p2)- chnh lch ap su*Hsthmnclathtchncthmquamdin 1m2 trong thi gian 1h khi chnh lch ap sut thuy ct nc. b.Tnh chng thm: h anh gia mc thm cua vt liuc anh gia bng ap lc nc ln nht ma khi vt liu co kch thc quy nh trong mt khoang thi gia* Vt liu lam vic dang khi:Mu th nghim co dacBm ncmu tch mt bn cua mu c boc vt liu cach nc, tGiao an Vt liu xy dng Trang 7 mu* Vt liu lam vic dang ban mong: Muthnghimhnhtroncochiudaybng chiu daylamvic.Mcncbanula100mmgi trong5n khMc thm hoc kha nng chng thm cua vt liu phu thuc vao cu tao ban thnvtliu( ccuavt m con phu thuc vao ap lc nc tac dung ln vt liu va thi gian thm.phut,sauoctphuttngthmhnccho i xut hin vt thm.4. Coc yu f onh huong dn fnh fhmvo y ngho: - c,rng,tnhchtlrng),banchtanchaykynliu.- S th- Tnh thm c bit quan trong i vi vt liu lam vic trong mi trng chu anh hng cua ma gio, thng xuyn m t hoc trong nc. * Nhcm coc fnh chf ||n quon dn m| fruong nh|f|X. 1NH 1kUN NH|1: . Kho| n|m: Tnhtruynnhitlakhanngcuavtliunhittruynquachiudaykhivt liu t pha co n. 2. CnTnhuyn s truyn nhit . H s truyn nhit la lng nhit truyn q m, tit din 1m2 trong thi gian 1h khi nhit chpha co nhit cao v nhit thp hg fhuc fnh: -trnhit c anh gia bng hua vt liu co chiu day 1nh lch gia hai b mt la 1oC. Qa=;Kcal/m.h.t FCt2t gia 2 b mt i xng; oC utaobanthnvtliu:ivinhngvtliukhtrong khngng thc kinh nghim sau: o trong o :Q-lng nhit truyn qua mu vt liu; Kcal a -b day mu vt liu; m F -tidin mu; mt-chnh lch nhi-thi gian truyn nhit; h 3. Coc yu f onh huong: a)Anhhngcuackh (W=1 7%) co th tnh theo o bng c14 , 0 22 , 0 0196 , 0 + =o ; Kcal/m.h.2 oC bnh qun cua vt liu:Khi nhit t = 40 70oC ta s u : b) Anh hng cua nhit tnh theo t bng cng thc a( ) to t002 , 0 1+ = trong o :t-h s truyn nhit toCoCa mu vt liu; oC o -h s truyn nhit 0t-nhit bnh qun cuGiao an Vt liu xy dngTrang 8 c) Anh hng cua m: Wk W + = trong o :W-h s truyn nhit cua vt liu trang thai m -gia s truyn nhit c sau khi un nong. Ky hiu Q. ynhitlaunotngln1oC.Ky hi2. Cn k -h s truyn nhit cua vt liu trang thai kh W - m cua vt liu X. NH|1 DUNG, 1 NH|1: . Kho| n|m: Nhit dung la nhit lng ma vt liu thuT nhitlngcncungcpcho1kgvtliu C. g fhuc fnh:Nhit dung c tnh theo cng thc sau:( )1 2t t CG Q =;Kcal Ty nhit cua mt loai vt liu c tnh theo cng thc sau : )trong o :C-ty nhit, Kcal/kg.oCG-khi lng vt liu c un nong; kg t1 -nhit vt liu sau khi un nong; oC t2 -nhit vt liu trc khi un nong; oC (1 2t t GQC=;Kcal/kg.oCt lng vt liu thu c sau khi ung nong; Kcal i lng vt liu c un nong; kg ; oC un nong; oC 3. Coc yu f onh hu trong o :Q-nhiG-kht1 -nhit vt liu sau khi un nongt2 -nhit vt liu trc khi ong dn fy nh|f: * Anh hng cua m: WWC CCn k01 , 0W01 , 0 1++= trong o :CW-ty nhit cua vt liu m W Ck -ty nhit cua vt liu kh Cn -ty nhit cua nc W - m cua vt liu (%) nghpvtliuhnhpdonhiuthanh ty nhit cua no tnh theo cng thc: *Anhhngcuathanhphncutao:trphn cu tao nn th nn n hhG G GC G C G C GC+ + ++ + +=......2 12 2 1 1 trong o :Chh -ty nhit cua vt liu hn hp Giao an Vt liu xy dngTrang 9 thanh phnphn X|. 1NH CHNH|1: :

+ Vt liu d chay 2- Tnh chu nhit la kha nng cua vt liu chu tac ng cua nhit cao trong mt ng b pha hoai (thng la b chay). vao kha nng chu nhit, vt liu xy dng c chia thanh 3 nhom : kho chay: chu c tac dung cua nhit t 1350 1580 C. 1 CO HOC CHU U CUA v1 L|U X DUNG ng la tnh cht cua vt liu b thay i hnh dang va kch thc di . Phung. nh cht hi phuc v hnh dang va kch thc ban u cua vt liu sau khi bo ngoai lc c ban u cua vt liuC1,..., Cn-ty nhit cua tng vt liuG1,..., Gn-khi lng cua tng vt liu thanh NG CHA, 1NH CH|U. 1nh chng choy: - Tnh chng chay la kha nng cua vt liu chu c tac dung trc tip cua ngon la trong mt thi gian nht nh ma khng b pha hoai. - Cnc vao kha nng chng chay, vt liu xy dng c chia thanh 4 nhom + Vt liu khng chay,khng b bin dang+ Vt liu khng chay nhng co th bin dang nhiu+ Vt liu kho chay. 1nh ch|u nh|f:thi gian dai ma kh- Cn c+ Vt liu chu nhit: chu c tac dung cua nhit ln hn 1580oC+ Vt liuo+ Vt liu d chay: chu c tac dung cua nhit di 1350oC. 2. CAC 1NH CH |. 1NH 8|N DANG: . Kho| n|m: - Tnh bin datac dung cua tai trong. -Thcchtcuabindanglakhichutacdungcuangoailccacphntsethay i v tr cn bng va co chuyn v tng i. 2 n |co| b|n dong: a. Cn c vao kha nng phuc hi bin dang: * Bin dang an hi: la bin dang b trit tiu hoan toan khi bo ngoai lc tac dTgoi la tnh an hi.* Bin dang deo (bin dang d): la bin dang khng b trit tiu hoan toan khi bo ngoai lc tac dung. Tnh cht khng hi phuc c hnh dang va kch th sau khi bo ngoai lc tac dung goi la tnh deo.b. Cn c vao thi im xut hin bin dang: * Bin dang tc thi: bin dang xut hin ngay sau khi t lc. * Bin dang theo thi gian : bin dang ch xut hin sau mt thi gian t lc. Giao an Vt liu xy dngTrang 10 3. Phn |co| vf ||u fhec b|n dong: -Cncvaoquanhgiangsutvabindang,haynoicachkhaccncvao in tg deo rt ro rang. VD: thep t cacbon, bitum... t khi t lc cho n trc khi b pha hoai mt cach ro rang. VD: gang, a thin nhin, gach t set nung...u co tnh an hi: la vt liu ma kha nng bin dang an hi ln hn kha4. Coc ng: ngbindangtngdntheothigiankhitaitrongtacdung khng ng. Mt khac, do ban thn cu tao cua vt liu co mt s thiu sot, khuyt tt v mt cu truc hoc do vt liu thay i cu truc n di tac dung lu dai cua ngoai lc no b chay nht ra . ng chung ng sut:nhn:doditacdungludaicuataitrong,mtphnnnglnggy : la kha nng ln nht cua vt liu chng lai s pha hoai di tac dung ua taia vt liu khi mu co hnh dang kch thc hun, cng la ch tiu quan trong nht anh g th nguyn do Nha nc quy nh cn c vao cng tiu chun. h ng bin dang ti trc khi b pha hoai, chia vt liu thanh: -Vtliucotnhdeo:lavtliumatkhitlcchontrckhibphahoai quan sat c bin dan- Vt liu co tnh gion: la vt liu makhng quan sat thy bin dang - Vt linng bin dang deo. - Tnh deo hay tnh gion cua vt liu co th thay i tuy theo cac yu t: nhit , m, tc gia tai... VD: bitum khi keo nhit cao la vt liu deo, khi keo nhit thp la vt liu gion... h|n fuong ||n quon dn b|n doa. Hin tng t bin: -Tbinlahinti. -Nguynnhncuahintngtbinladotrongvtliurncomtsbphn phi tinh th co tnh chay nht gn ging nh th lotheo thi gian nb. Hin t-Chungngsutlahintngngsutanhigiamdntheothigiankhigi cho bin dang khng i. -Nguyn bin dang an hi b mt i di dang phn tan nhit lam cho mt b phn vt liu co bin dang an hi dn dn chuyn sang bin dang deo. ||. CUONG : . Kho| n|m: - Cngctrong va c xac nh bng ng sut ti han tng ng vi tai trong gy pha hoai mu. Ky hiu R. - Cng tiu chun: la cng cucc ch tao, dng h trong iu kin tiu chun, th nghim theo phng phap chun. Ky hiu Rtc. - Mac vt liu (i vi cac vt liu magia cht lng): la ai lng khn Giao an Vt liu xy dngTrang 11 keo, chu nen, chu un... p: hoc l t cu cng trnh va tac dung tai trong trc tip ln muchonkhimubphahoai.Sxuthinvtnt,stachlpvabindanglacac cktquathnghimtheocaccngthc gnenR :muthnghimthngcodanghnhkhilp phng- Trong cac kt cu xy dng, vt liu co th chu cac loai tai trong khac nhau: keo, nen,un,ct,trt,...Tngngvimidangchutaisecomtloaicngtng ng: cng chu- Khi th nghim, s pha hoai trn mu xay ra khi co cac du hiu : t , tach lp , nt, bin dang ln, gay... 2. Phuong phop vo cng fhuc xoc d|nh: a. Phng phap trc ti- Ch tao muy mu t kdu hiu pha hoai. -Cngvtliuctnhtoantcatng ng vi dang chu lc . *Xacnhcnn , canh t 2 n 30cm. P FPRn = trong o :P - tai trong pha hoai F - din tch mt ct ngang* Xac nh cng chu keo Rk : mu th nghim co hnh lng tru , hnh s 8. FPRk= trong o : P - tai trong pha hoai F - din tch mt ct ngang imth angthanh(dm), ri tac dung ln thanh m ayt ong tp trung. 1 tai : Trng hp t mt tai trong gia : P PF *XacnhcngchuunRu:muthngh ngcodtit din ch nht, t trn 2 gi tat hhai ai tr+ S 22bh3PlRn= =WM i lPbh + S 2 ta : Trng hp t hai tai bng nhau i xng vi im gia cua thanh: 2bhPlWMRn= =l bhP/2//3P/2//3//3 trong o :M- mmen un ia hai gi ta b, h- chiu rng va chiu cao tit din W- mmen khang un cua tit din ngang dm P- tai trong pha hoai l- khoang cach g Giao an Vt liu xy dngTrang 12 hoc: t vt liu ri o tr s bin dang deo, thng s o la cu tao ra khi co cua xung in, tia phong xa hay song siu m khi i ring hay vn tc truyn song. em i cua vtliu . khngphahoairttinlisongmcchnhxactuythuc chuncuaphngphapkhngphahoaiphaicxydngtrncscua tao vt liu: o hn vt liuco kin truc kt uttp hoc si, thanh phn cu tao phn b theo mt chiu nht Hnh dang va kch thc mu: mu co hnh dang khac nhau th tr s o cng c trng b mt: trong th nghim nen th mu co b mt trn lang, lc ma sat se b. Phng phap gian tip: da vao nguyn tc cua dung cu o* Nhom theo nguyn tc c- Tac dung tai trong su vao b mng hay bin dang cuc b (bua bi, bua co thanh chun). - Tac dung tai trong va cham vao b mt vt liu, da vao nguyn tc ny bt an tnh ra khoi b mt vt liu, thng s o la tr s bt ny do phan lc t mt vt litac ng c hoc (sung bt ny ). em cac thng s o c i chiu vi cac th chun tng ng cua dung cu suy ra cng cua vt liu. *Nhom theo nguyn tc vt ly:- Da vao quy lut lan truynqua vt liu xac nh mt , tn s dao ngchiu cac thng s o vi cac th chun xac nh cng - Dung cu o : may siu m btng , may siu m thep...*Cacphngphap vao rt nhiu yu t do o khng th thay th hoan toan phng phap pha hoai mu c . Cacbiu phng phap pha hoai mu . 3. Coc yu f onh huong dn cuong d vf ||u: a. Cac yu t phu thuc vao ban thn cu- Vt liu co cu truc kt tinh hoan thin co cng cao hn vt liu co cu truc kt tinh khng hoan thin. - Vt liu co kin truc kt tinh mn co cng catinh th. - Vt liu co cu tao rng co cng thp hn vt liu c chc v no co rng tngiln,lclinktgiacacchtimyu,dintchchulcgiam,ngstrung gn l rng, nn kha nng chu lc kem . - Vt liu co cu tao dang lpnh nn cng theo mi hng khac nhau (tnh d hng). b. Cac yu t phu thuc vao iu kin th nghim: - cung khac nhau. VD: trong th nghim nen th mu co kch thc cang be, chiu cao cang thp th tr s o R se cao; mu hnh tru co tr s o R thp hn mu hnh lng tru. - nho, cng se thp va ngc lai. -Tctngtai:khitctnglccangnhanh,tcbinhnhcuavtliu chm(tngi)sovitctngtainntrsoRsecaohnsovithc t. Giao an Vt liu xy dngTrang 13 - Nhit va m cua mi trng: co anh hng n cng . i vi cac vt liu nhay cam vi nhit va m th anh hng cua m va nhit n cng rt ln . khcp dang, kch thc chun, iu kin ch ta m chun cho tng loai vt li (Tiu chun Xy dng cua Vit Nam, Tiu chun nganh cua cac B chu quan, Tiu chun cua cac nc trn Hip h c Quc t cng nh n). Khi th nghim trn cac i s hi nh kt qua v iu kin chun . Vhnhdangvakchth nhhngnhtnhnktquathnghim cng nn i vi Rn ngi ta s iu chn : i vi th nghim nen cua btng: H s diu ch iua cac loai khun mu (ly khun 15 x 15 x 15cmlam tiu chun) oc mu (cm)K huccacyu tanh hngo,phaiquynhmthnh o va dng h chun , phng phap th nghi th gii, Tiu chun cua cac u kin khac chun, phai coi u chcmucoa phai dung h h. VDnh cuong d gHinh dang, kich thu 15 x 15 x 15 10 x 10 x 10 1,00 0,91 30 x 30 x 30 20 x 20 x 20 1,10 1,05 d = 20 ; h = 401,24 1,20d = 15; h = 30 s bn rong mi trng nc ta dung h s mm K 4. Coc h s ||n quon dn cuong d: a. H s mm : -Nhn chung khi vt liu bao hoa nc th cng giam. anh giacua vt liu khi lam vic tm kbhmRRK = trong o : Rbh _-cng cua mu vt liu a bao hoa nc Rk -_cng cua mu vt liu kh - H s mm bin i trong gii han t 0 (vt liu bng t set khng nung) n 1 (vt li ng trnh b ngp nc hay chu mm ln hn 0,75. nhtoanthitkcngtrnh,ngitachtnhkhanngchulccuavt u hoan toan c chc: thep, knh...). i vi cac cmc nc thay i lin tuc hay b nc va p lin tuc yu cu h sNhng vt liu co h s mm ln hn 0,75 c goi la vt liu bn nc. b. H s an toan: -Trongtliu theo tr s cng ti a cho phep [ R ]. Cng nay nho hn cng gii han Giao an Vt liu xy dngTrang 14 thc s an toan K lun lun ln hn 1. cua vt liu mi am bao an toan. Ty s gia cng gii han va cng cho phep goi la h s an toan K. H s [ ] RRK = trong o :R - cng gii han cua vt liu [R] - cng ti a cho phep trong thit k * Ly do a ra h s an toan trong tnh toan tht k kt cu cng trnh : rung bnh cua nhiu mu th nghim, nhiu vung hoc nhiu n th ng co hin tng moi hoc a co bin hnh hoai (nht la khi tai trong trung lp)., ngi ta cha cp ht n cac yu t anh hng cua mi trng thuc vao : - Quy m, tm quan trong cua cng trnh . m v tnh toan thit k, phng phap tnh, trnh tnh toan, trnh liu, kim nghim qua cac cng trnh a xy dng... cht: - Cng la tr s tl nghim. - Trong qua trnh lam vic, vt liu thqua ln tuy cha n lc pha- Mt khac khi thit k tac dung ln cng trnh. * Vic la chon h s an toan ln hay nho khi tnh toan tuy - Kinh nghinm chc vt - Phng tin, thit b thm do,khao sat, d bao, kim nh ... c. H s phmHsphmchtKpclachtiuanhgiaphmchtcuavtliu-latysgia cng va khi lng th tch cua vt liu. opcRK =|||. CUNG: . Kho| n|m: - cng la kha nng cua vt liu chu c s xuyn m cua vt liu khac cng hn tac dung ln no. - Kha nng nay rt quan trong i v vt liu lam ng, vt liu lat b mt, vt li coiu n tnh cht ch cng cung trng cho m ng cua vt li2.Coch xoc d|nh*iv n cnhla phngphapva khng nh lng. trong o :R-cng gii han cua vt liu, daN/cm2

o-khi lng th tch cua vt liu, kg/m3

i u lam tru cu... va anh hng nh u mon. Mt khac, c c kho gia c u. : ivtliukhoang:dungthaxacnhtheophgcngMohr.Phngphapxach.Cach ngphapnaychcotnhchtnhtnhch Giao an Vt liu xy dngTrang 15 Bang thang h s cngKhoang vt cng Mohr C c im cng 1 2 3 4 5 6 7 8 9 10 phn Canxit hay thach cao cng tocla ach anh a on ng ang bng mong tay Rach c bng mong tay Rach c d dang bng dao thep o thep di ap lc khng ln n irac khngrach Khngcbngdaothep,chlam knh b he Coth nhddang,khngrachc bngTan hocThach cao FluroinRach c bng daApatit Oc ThTopCoriKim cRach c d ddaomanhmc knh hc, rach xc nrachk dao thep Cn c vao bang Mohr th cng mt s cht nh sau : Tn cac chtD cungTn cac chtD cung Cu hoa Thuy tinh Thep t C 2 - 3 3 - 4 4,5 - 6,5 6 6,5 4 - 5 Pb Zn 1,5 1,5 -2aAl2 Sn2a la Li daoThan a Mong tay2 - 2,5 2,5 *i vi vt ling knh D (mm), em n vao vt mt vt liu ma xac u kim loai :+ Phng phap Brinen: dung vin bi thep co liu nh th vi mt lc P, ri da vao kch thc vt cu lom trn bnh cng. cng Brinen xac nh theo cng thc sau: P ) (2 2d D D DFBr trong o :F -din tch chom cu cua vt lom, 2P PH = = , daN/mm2

mm2

D - ng knh bi thep; mmd- ng knh vt lom; mmDd Giao an Vt liu xy dngTrang 16 P - lc ep vin bi vao mu th nghim ( N), no phu thuc vao ng knh vin bi va loai vt liu. P c tnh theo cng thc P = KD2

t liu. V du: +Phngphkimcngcodungmrnh t tin hanh nh sau: Cho tai trong ban u la: 10kg ri tng dn ln 150kg (nu dung hnh non) Po = 10kg ri tng dn ln 60kg (nu dung bi co D = 1,59mm) co D = 3,175mm) o bin dang de con lai trn mu(co n v la 2). 100 - e (nu dung hnh non kim cng) 75mm va P = 100kg) |v. MA| MON: . Kho|th th tch va khi lng iu M . mon li- mai mon phu thuc vao cng, cng va cu tao ni b vt liu. 2. Coch xoc d|nh:-maimonthngcthnghimbngmaymaimon.Muthnghimhnh tru co d = 2,5cm, h = 5cm. Cho may quay 1000 vong va rc vao 2,5l cat thach anh c 0,3 0,6mm va mai mon c tnh theo cng thc: da K - la h s, phu thuc tnh cht vi vi kim loai en, K = 30 i vi kim loai mau, K = 10 i vi kim loai mm, K = 3 HBr cang ln th vt liu cang cng. apRc-oen:dungmthnhnonbng gocm120o,banknh0,2mm,hoc thonbithepcongknh1,59mmhay 120P 1 13 32 23,175mmtacdungsuvaobmtvtliuvitai trongtngdn.Sauokhiphuclaitaitrongban u ri o bin dang d e . Cn c vao e anh giamc cng cua vt liu . -TPo = Po = 10kg ri tng dn ln 100kg (nu dung bi co D = 1,59mm) Po = 10kg ri tng dn ln 100kg (nu dung biSau o khi phuc lai tai trong ban u Po = 10kg cng Rc-oen c ky hiu va tnh toan nh sau: HRc =HRb = 130 - e (nu dung bi co D = 1,59mm va P = 100kg) HRf = 130 - e (nu dung bi co D = 1,59mm va P = 60kg) HRe = 130 - e (nu dung bi co D = 3,1 n|m: - Khi vt liu lam vic b co xat lin tuc vi vt liu khac cua no b thay i, ta goi vt liu b mai mon. Ky hn- mai mon la hao mon v khi lng trn mt n v din tch mu b mai n tuc . Giao an Vt liu xy dngTrang 17 FG GMon= ; g/cm2

trong o trc khiG hi lng mu trc khiF -din tch mai mon; cm2

- Cung co khi ngi ta anh gia mai mon bng hao hut chiu day cua mu.ung bnh mai mon cua mt s vt liu :Go -khi lng mumai mon; g

-k mai mon; gDi y la ch s tr Vt liuD mai mon, g/cm2a hoa cng (granit) tha0,1 - 0,5 a ch anh0,06 - 0,12 Tm lat san bng gm a vi 0,25 - 0,3 0,3 - 0,8 v. CHNG vA CHAM: . Kho| n|m: chng va cham la kha nng cua vt liu chu c tai trong va cham ma khng pha hoai (thng la b nt). va cham c tnh bng cng cn thit p v mt iu . nh: nh h p vao b mt mu vt liu n ln cho n khi xut hin vt nt u tin a hoai do tai trong va cham gy ra : . h. n|. HAO MON: tcuavtliuvachumaimonvachuva xacn an(ivia).pathanh hngin n g kh hung quay 10000 vong ri theo cng thc sau : bn v th tch vt l2. Coch xoc d|- Dung may bua va cham: tha cho qua cu thep khi lng G ri lin tuc mt cao xactrn mu. Cng phAvc = g. G- chng va cham cua vt liu c tnh theo cng thc sau : avc = Avc/Vo

v. Kho| n|m: haomonctrngchotnhchcham.2.Coch xoc d|nh: * hao mon van: - hhaomonthngdungmayvn v n oang 100g ri bo 5kg a vao thung. Cho tly mu ra va em sang qua sang 2mm. hao mon se c tnh % 1002 1=G GH1Gm trong o :Q- hao mon; % Giao an Vt liu xy dngTrang 18 G1 - khi lng vt liu trc th nghim; g G i lng vt liu sot lai trn sang 2mm sau th nghim; ghng hao mon rt yu vao may, bo vao n vin bi thep (d = 48 mm; g = 405-450g), cho may quay N8,9,11; khi Dmax 20mm th N = 1000v , n = 12. Sau o em sang qua sang 1,25mm . hao mon c tnh n nh n . * T SH 6-87; STM131-8- Phn loai nh caloai A B, C, D, E , F, . K nhiu c th phai sang phn th tng ng r i phi hp lai tao thanh muC t khi lng vt liu G cho may o n vin bi thep (d = 46,8 mm ; g = 390-445g ) , cho may quay N vong v 3v/p u o anqua s 71mm . haoc tnh theo cngnhng phn loa heA TO 9 -87; ASTM C131-81 L S BG 2 - kh- Cn c vao hao mon van , phn a thanh : Q < 4% - a chng hao mon rt khoe Q = 4-6% - a chng hao mon khoe Q = 6-10% - a chng hao mon trung bnh Q = 10-15% - a chng hao mon yu Q > 15% - a c* hao mon LosAngeles (LA): - xac nh hao mon LA thng dung may hao mon LA* TCVN 1772-87 : -CnmtkhilngvtliuG,KhiDmax20mmthG=5kg;KhiDmax 20mm th G = 10kg. Khi a co nhiu c th phai sang phn c va xac nh hao mon cho tng c hat. Cho mu vong vi tc 30-33 v/ph. Khi Dmax 20mm th N = 500v, n = theo c g thc trC AA TO 9A C 1: a tha c , G hi a coanh c ri th . n m vao , bo vai tc0-33 h. Saem s g ang 1, mon thc trn.Ba i da t o TC A H S 6ot qua ot laiACDEF 76,263,52500 63,550 ,8 2500 5 38 0,8 ,1 50005000 38,125,41 5 5000250 00025,419,112505000 19,112,712502500 12,79,5212502500 9,526 ,352500 6,354,762500 4,762,385000 Tng G5000500050005000100001000010000 N500500500500100010001000 n121186121212 Giao an Vt liu xy dngTrang 19 CHNG II : ..------------------------- VRT LlEU R THlEN NHlEN tm hiu loai vt liu c dung nhiu trong xy dng. p c yu t o ng , tnh bn nhom chnh: a macma, cma thanh 4 loai: 2* a macma baz : khi ham lng SiO2 = 55- 45% . KHA| N|M vA PHN LOA| |. KHA| N|M: . vf ||u do fh|n nh|n: -Vtliuathinnhinlavtliuxydngcsanxutratathinnhin bng phng phap gia cng c hoc nh n mn, uc, p, ca, v.v... Do o, tnh cht c ly, hoa hoc cua vt liu a thin nhin vn gi nguyn nh cua a gc. V vy, tnh cht cua vt liu a thin nhin ta phai tm hiu tnh cht cua a thin nhin. 2. o fh|n nh|n: - a thin nhin la nhng khi t hp v c co quy lut cua mt khoang hay nhiu khoang. a ch gm mt khoang goi la a n khoang, a gm nhiu khoang goi la a a khoang.- Khoang vt la c s kin tao nn a thin nhin. o la mt khi vt th ng nht than v h phn hoa hoc, tnh cht vt ly va kin truc tinh th. Khoang vt la nhng cht hoa hoc c tao thanh do kt qua cua cac qua trnh hoa ly t nhin khac nhau xay ra trong vo Trai t. * Vt liu a thin nhin la- Cng dung: Vt liu a thin nhin nh cat, soi, a dm dung lam ct liu btng va va; a cp phi dung rai ng t va m ng xe la; a hc dung xy m cu, xycng, kevagiacnnng t vung tyu;atm,alatdunglatvahe, lambccuthang;caccukinkintruckhacdungtranghoangcaccngtrnhdn ung v d a cng cng. Ngoai ra, con dung a thin nhin san xut cac cht kt dnh nh vi, thach cao, ximng. -uim:cngchunencao,cngcao,bnvngtrongmitrngsiu a phng.dung, kha nng trang tr tt va gia thanh ha, v la vt l ||. PHN LOA| A 1H|N NH|N: - Co nhiu phng phap khac nhau phn loai a thin nhin, song phng phahay dung nht la da vao iu kin sinh thanh va ngun gc cua chung, v caquyt nh thanh phn khoang vt, cu truc tinh th, kt cu cung nh cvng va kha nng trang tr cua a. - Theo phng phap nay, a thin nhin c chia thanh 3a trm tch va a bin cht. - Ngoai ra, cn c vao ham lng oxit silic co th chia a ma* a macma axit : khi ham lng SiO2 > 65% * a macma trung tnh : khi ham lng SiO= 65- 55% Giao an Vt liu xy dngTrang 20 * a macma siu baz : khi ham lng SiO< 45% a macma xm nhp a trm tch c hoc a bin cht tip xuc|N NH|N: c: a cng eo got, khng co dang hnh hoc xac nh, kg. vin co qua gia cng c hoc, hnh dang thng la khi hp ch .vi cac kch thc con lai. 5 70 mm 3 00, 1000 15, 75, 100, 150 - a co Km = 0,6 0,75 : dung ni t m- a co Km = 0,75 0,9 : dung ni m t- a co Km = 0,6 0,75 :dung di nc. Cn cu voc muc dch xy dung: - a xy mong, lam ct liu phan, dung lam vt liu trang tr, liu san xut vi, ximng... c 2 a macma a macma phun traoa thin nhina trm tch a trm tch hoa hoca trm tch hu c a bin cht a bin cht khu vc |||. PHN LOA| v1 L|U A 1H. Cn cu voc hnh dong, kch fhuo- a hc: nhng vin cha qua gikch thc 150 450mm , G = 20 40 - a khi: nhng nht, thng c goi la a eo: a eo th, a eo va, a eo ky- a tm : nhng vin co chiu day be hn so - a dm: a co d = - Cat: hat co d = 0,14 5 mm - Bt a: d < 0,14 mm 2. Cn cu voc kh| |uong fh fch: - a nng: KLTT > 1800 kg/m3

- a nhe: KLTT < 1800 kg/m3. Cn cu voc cuong d: - a nng: co cac Mac 100, 150, 200, 400, 600, 8- a nhe: co cac Mac 5, 10, 4. Cn cu voc h s mm: - a co Km < 0,6 : dung ni kh rao 5 cho btng, btng ata p lat, dung lam nguyn 6. Cn cu voc quo frnh son xuf : - Vt liu a co qua gia cng c hoc- Vt liu a khng qua gia cng c ho Giao an Vt liu xy dngTrang 21 2. A MACMA |. C |M HNH 1HANH: -amacmactaothanhtkhisilicatnongchaytronglongvoTraitxm lp vo nay phun ln trn b mt cua vo Trai t ri ngui .coquatrnhkttinh c tt, t hut nc. hanh di nhit va ikchthctinhthbe, iu l rng, kha nng chu : 3chu neThach oc m c nhau va plagiocla - khi cac mt cat khai xin goc vi nhau n2 3 22 3 2 mau trng, trng xam, vang hng n o, khi lng 3ng66,5,cngchunengiihan1200 00da bin nht la 2 loai biotit ca rt thp, noi chung t 2 nhp vao vo qua t hay pha vlanh lai tao thanh-MacmaxmnhpnmsuhntronglongvoTraitvaNo co cu truc tinh th ln, c chc cao, kha nng chu l chm.- Macma phun trao trn vo Trai t va qua trnh kt tinh napsutthpnncomtbphnkhoangkhoangvtkttinh khng hoan chnh, con phn ln dang v nh hnh. No co nhvlc kem nhng hoat tnh lai cao... ||. CAC KHOANG v1 1AO A. Nhcm s|||cof:a. Thach anh: - Thach anh co thanh phn hoa hoc la SiO2 dang kt tinh, tinh th hnh lng tru sau canh, t khi trong sut ma thng co mau trngsa, cng 7, khi lng ring 2,65g/cm , co cng n cao, chng hao mon tt va tng i n nh vi axit. anh co kha nng thay i th tch tuy theo nhit . t = 573oC b bin i thu hnh, n V 1,5 ln. to = 1710oCnong chayb. Nhom fenpat: - Gm nhng alumo silicat natri, kali va canxi c tao thaTinh th Thach anh anh nh khi macma kt tinh. Cncvaotnhchtcatkhai,ngitachiafenpatralam2dang:octola-khi ca t cat khai thng gog 86o30).(khoa- Co 3 loai : fenspat kali, fenspat natri, fenspat canxi K2O.Al2O3.6SiO2 Na2O.Al O .6SiO CaO.Al O .6SiO c tnh c ban cua fenspat la co -ring2,552,76g/cm ,cN/cm217 ,khanngchngphonghoakem,kemnnhivinc,cbitla nc co cha CO2. Fenspat kali khi phong hoa tao thanh Caolinit. -Fenspat dung chu yu trong cng ngh san xut gach men s va cac thit b s v sinh. c. Nhom phu mica: - Mica la nhng alumosilicat ngm nc rt phc tap, phco mau nu, en va mutcovit thng trong sut. cng cua mi3 3, khi lng ring t 2,76 3,2g/cm . Giao an Vt liu xy dngTrang 22 d. Nhomkhoang vt sm mau: -Ogyt:Thanhphnhoahocphctap,Ca(Mg,Fe,Al)[(Si,Al)2.O6]comauen 6, khi lng ring 3,2 3,6g/cm3, do macma ngui lanh t nh oxen.Tronggranit,tyl hiu nht nn quyt nh mau cua granit t xam sang ti hng.sdungchuyuptrangtrmtngoainhacavacaccng ngtrnhcngcng,lam nnmongcu,cng, p.ncta,granitco gcothachanhnntylSiO2nhohnnhiusovigranit.Thanhphn hoang400 2800 kg/m3, cng chu nen gii han 1500 2000 daN/cm2. ng dung cua granit. nh thoang con co thach anh. iorit thng co mau xam, x chng va cham tt, chng phong hoa cao va d anh bong nn ng va tm p. Vit Nam, iorit gp nhiu in Bin hu. pht luc, pht nu; cng 5tao thanh. - Amfibon: Thanh phn phc tap hn piroxen, ph binnht la hocblen va actinolit. Hocblen co tinh th lng tru, mauluc hay nu, cng 5 6, khi lng ring 3,1 3,3g/cm3, do macma ngui lanh tao thanh. Actinolit co tnh cht ly hoc tng hocblen, do ogit bin i tnh cht ma sinh ra, tinh th hnh si mau luc, cng 5,5 6, khi lng ring 2,9 3g/cm3. 3. Coc |co| do mocmo fhuong gp: a. a macma xm nhp: ` Granit Tinh thhocblen-Granit (a hoa cng) la loai a axit co nhiu ni, thanh phn khoang vt gm cothachanh(2040%),fenspatkali(4070%),mica(220%)thnglamutcovit, ngoairaconmtskhoangvtmausmmhamfibon,piroctocla chim n- Granit co cu truc tinh th hat, khi lng th tch 2600 2700 kg/m3 , cng chu nen gii han t 1000 2500 daN/cm2 hoc cao hn, cng chu keo bng 1/40 1/60 cng chu nen. hut nc nho (di 1%), kha nng chng phong hoa rt cao, chulakem,comtsloaicomauscep.Theokchthchat,granitcchia thanh ba loai: hat nho, va va th. -agranitc trnh cbit,cnhiu Thanh Hoa, Ta Khoa, Phanxipng, Ca Rao, Nui ng. ` Sienit -Sienitlaloaiatrungtnh,gmnhngtinhthcokchthckhacnhau.Thanh phnsienitkhnk vtchuyucuasienitlaoctocla,plagioclaaxitvacackhoangvtmausmnh biotit, hocblen. Sienit mau tro hng, khi lng ring 2700 2900 kg/m3, khi lng th tch 2sienit ging nh * iorit -ioritlaloaiatrungtnh,thanhphnchuyugmplagioclatrungtnh(chim khoang 3/4), hocblen, ogit va biotit, tham luc, khi lng th tch 2800 3300 kg/m3, cng chu nen gii han 1500 2800 daN/cm2. -iorit dai, co kha nngc s dung lam mt P Giao an Vt liu xy dngTrang 23 50%)vacac khoang3,cng chun atm lam m p b mt. i : pocfia thach anh - tng t hach anh - tng t sienit; va pocfiarit - tng t iorit. Bnh). ng t sienit, cu tao rng, khi lng th tch gn 22 ng chu nen gii han 500 900 daN/cm2, thng co mau sang hay xam saplagiocatrungtnhvacac khoangc a dm ch tao btng axit. iabaztngtgabro.Bazanlaloaiaphunxutphbin nht,k 3300kg/m3, Khicovtntvalrngth ng n dung ch cao. ` Gabro -Gabrolaloaiabaz,thanhphngmcoplagioclabaz(khoangvtmausmnhpiroxen,amfibonvaolivin.Cutruccuagabrotngtnh granit nhng chu yu la loai hat ln.Gabrothngcomau sm en, khilngthtch2800 3300kg/mengiihan20003500daN/cm2.Gabrodungsanxutraadm,t ng va b. a macma phun xut: ` a pocfia - a pocfia la loai a axit, co th chia thanh nhiu loagranit; pocfia thiu t- Tnh nng xy dng cua pocfia gn ging cac loai a xm nhp nhng do cu truc khnguvabxmnhim(scomtcuacachatlnfenspat)nnkhanngchng phong hoa kem hn. a pocfia dung san xut ra a dm va cac cu kin khac. - Vit Nam, a pocfia co Ta Khoa, Lai Chu va Kim Bi (Hoa* a iaba -aiabalaloaiabaztngt gabro, cokchthchatkhacnhau,mauluc, cng chu nen gii han n 4500 daN/cm2, kha nng chng va cham tt va t b mai mon. a iaba dung san xut vt liu a lam ng. ` a trachit - a trachit la loai a trung tnh t00 kg/m3, cng. Trachit d b mai mon va kha nng chng phong hoa kem. atrachitthng dung xy tng va san xut a dm ch tao btng nhe. ` a anzit -aanzitlaloaiatrungtnh,thanhphngm vt mau sm nh ogit, khi lng th tch 2200 2700 kg/m3, cng chu nen giihan6002400daN/cm2,comauxamnxamsm.Anzittngtnhiorit nhng co cu tao c va co tnh axit hn, thng dung lam vt liu chng axit va san xut ra tm p ho* a bazan -abazanlaloahilngthtchgnbngkhilngringvavaokhoang2900cngchunengiihancokhiatn5000daN/cm2. c giam i rt nhiu va co khi ch con 1000 daN/cm2. a bazan co cng ln va don nn kho gia cng, ngi ta dung chu yu lam vt liu rai mt ng t va lam ct liu ch tao btng. Ngoai ra a bazan cotao cac thit b ng, tm p chng n mon hoa hoc v khi nu chay ri uc lai no co cng rt Giao an Vt liu xy dngTrang 24 ncta,abazanvaconcoVnhLinh, chu nen rt nho t 60 100 daN/cm . trong , nc, tac ng hoa hoc a mt s t a b phong hoa v vun ra. Nh co gio va nc cun i, lng ong lai tao o Trai t. Qua cac thi ky a cht, lai gn kt vi nhau sinh thanh chia a trm tch thanh 3 loai: a trm tch c hoc, hoa ho . c vt tao thanh. xit silic: * Opan: hvnhhnh,laoxitsilicngmnc(SiO2.nH2O),mau trng,c khng mau, trung bnh cha khoang 6 34% nc. Opan co th kt hp v at tnh. Khi lng )2nhitbnh v nh hnh dang si. Khi lng th tch 2600 kg/m3 , cconhiuTyNguynPhu Quy, in Bin. * Cac san phm nui la dang ri rac hoc dang keo kt hoa. - Loai ri rac nh tro nui la, cat nui la, soi a bot. - Loai keo kt hoa nh tup nui la, tup dung nham, trat. Loai nay co rng ln r = 80% , khi lng th tch be bng 0,5 kg/l , co h s truyn nhit t 0,12 0,2 , cng 2Cac loai nay dung lam ct liu cho btng nhe hay dung lam phu gia hoat tnh chu nc. 3. A 1kM 1CH|. C |M HNH 1HANH: -atrmtchlanhngloaia,docackhoangchtlngonghaykttua nc, tch luy thanh tng khi sinh ra. Di tac ng cua nhit mthanh tng lp di ap lc cua vbng cac cht kt dnh thin nhin. - Cn c ngun gcc va hu c- a trm tch c hoc: do cac san phm vun nat sinh ra trong qua trnh phong hoa cac a co trc, tch tu hoc lng ong trong nc tao nn. - a trm tch hoa hoc: do cac khoang cht hoa tan trong nc, kt tua, lng ong xung ri lai gn kt vi nhau lai tao nn. Thanh phn khoang cua no n gian hn.- a trm tch hu c: do cac xac ng th ||. CAC KHOANG v1 1AO A:Trong nhom nay thng gp nht la thach anh, opan va limonit. a. Nhom o-Cocutructinhtvang, o hoi vi nhit thng tao thanh silicat nn con goi la cht horing2,5g/cm2,cng56,don.CothtngtacviCa(OHthng. Dung lam cht phu gia hoat tnh vc. * Canxeoan:- SiO2dang ng 6. * Thach anh trm tch: lng ong trc tip t dung dch hay do tai kt tinh t opan hay canxedoan Giao an Vt liu xy dngTrang 25 b. Nhom cacbonat: * Canxit: Tngiphbinvotrait,thanhphnhoahocla CaCO3h, tinh th khi mt thoi, khng mau hoc mau aCO3.MgCO3.olomitcotnhchtlyhocgnging canxitn, bn hn va t hoa tan trong nc hn. Hoa tan manh trong dung h phn hoa hoc la MgCO3, mau trng pht va lng ring 2,9 3,1g/cm3. H2O va la mt khoang vt in hnh uaatrmtch,dangkttinh,tinhthdangban,ikhidangsi,g 2,3g/cm3. Thach cao d hoa tan trong nc, hoadrit: cng 3 3,5, khi lng m khoang vt set .2SiO2.4H2O tmorilonit : Al2O3 .4SiO2.2H2O theo at nui, cat sng va cat bin. nh phn quan trong san xut btng, va xy dng, gach silicat. -Sathachlaloaiadocachatcatthachanhc ximng hoabng tse t,oxit silic, oxit st hay cacbonat canxi tao nn. Cng cua no phu thuc vao cht lng cht , dang kt tinsa, khi lng ring 2,6 2,8g/cm3, cng 3, t hoa tan trong nc nhng d tan trong nc co CO2. * olomit: ThanhphnhoahoclaCTinh thcanxitnhng cng hdch HCl ngui 10% dang bt. * Manhezit: Manhezit c tao nn t trm tch, co thanng, cng 3,5 4, khi c. Nhom sunfat: * Thach cao: Thach cao co thanh phn hoa hoc la CaSO4.2cmau trng, cng 1,5 2, khi lng rin tan ln hn canxit 75 ln. * AnhyAnhydrit co thanh phn hoa hoc la CaSO4, dang kt tinh, tinh th dang tm day hoc hnh lng tru, mau trng, i khi co mau xanh da tri,ring 2,8 3g/cm3, do trm tch hoa hoc tao thanh. d. Nho* Caolinit :Al2O3 .2SiO2.2H2O * Haloisit : Al2O3* Nhom Mon |||. CAC LOA| A 1kM 1CH 1HUONG GP: a. a trm tch c hoc: ` Cat: - Cat la hn hp ri rac cua cac loai a khac nhau, co ln t 0,15 5mm. Tuyiu kin tao thanh ma co c- Cat la tha` Soi: Soi la loai hat tron canh, nhn co kch thc t 5 70mm c dung rt nhiu lam ct liu ln cho btng. ` Sa thach: Giao an Vt liu xy dngTrang 26 kt dnh thin nhin, trong o sa thach silic co cng cao nht (Rn = 2000daN/cm2), co cng cao nht va co gia tr xy dng tt nht. - Trong xy dng dung sa thach silic lam a dm ch tao btng va rai mt ng. b. a trm tch hoa` a vi: -Cot ngvtchuyu3vamts htnhset,thach anh, oxit st, c tao thanh trn cbin, vung,c s cac di tch ng, thc v ng ong hoa h ch tu cua ca nh v ri rac, ri c len c lc nc va c gn g cacbonat- a v o = 1700 26 , Rn = 100 N/cm2, mau trng hocvangxa nghungonuco ht.Cnamlngsetma ngi ta chia a thanh cac loai nh ba . oai da viTy l CaCO3 (%)Ty l set (%) hoc hanhphnkhoa laCaCO tapc... a vi ac vnhh trnt cung nh s l oc; s t c vo so, maht bi ap kt bncanxi. i co cng 3,00kg/m3 1000danh,xam,hu lntapc cvaoh a vi r ng sauL a vi tinh khit t vi 98 100 0 75 10 40 2 10 2 0 60 25 90 60 98 90 a vi t set a vi nhiu set t set vi 90 98 75 90 410 2 25 10 t set nhiu vi t set t set 0 2100 98 * a olomit * a manhezit ng, ngi ta dung a vi san xut ra a dm lam ct liu btng, a ximng. ng nhe. thanh phn nh oc san xut ra vi va ximng. * iatomit va trepen: - y la cac loai a trm 95% oxit silic v nh hnh. iatomitcothtrangthairirachocgnktyu,thngcorngln,mautrng * Thach cao - Trong xy drai mt ng t, mt ng xe la, ch tao tm p, tm lat va cac cu kin kin truc, cung nh dung san xut ra vi vb. a trm tch hu c ` a vi so: -avisolaloaiarng,gmcacmanhvoso,hncximnghoabng cacbonatcanxi,thanhphnkhoangvtchuyulaCaCO3,o=6001500kg/m3,Rn = 4 130 daN/cm2. a vi so c dung lam vt liu xy dng va lam ct liu bt` a phn: - a phn la loai a bao gm cac manh vun cua vo so, vo hn, coa vi song co cng nho hn. a phn dung san xut bt mau trng h tch thc vt, co cha 80 Giao an Vt liu xy dngTrang 27 vang hay xam va c sinh ra h hay bin bi cac loai vo silic cua ng vt hoc cac ai taoccutaotnhnghatopanhnhcuva t t cdunglamvtliucachnhitvalamphugiaNH 1HANH: va ap sut ln, cac loai a macma va a trm t khu vc: c tao thanh t cac loai a b bin i tnh cht di tac vabin tai kt tinh cua a vi di tac dung cua nhit cao hay ap u mau sc nh trng, vang, hng, o, en, v.v... trong a thng co . rang tr nh ch tao cac tm mong p mt cng trnh, lam bc ng, o hay tm, co kha hoa tt, cng chu nen gii han at n 4000 daN/cm2, co cng cao nn kho gia cn- a quczit ung cho nha ca, lam a dm, a hc cho c u chu la. thach set d tach thanh tng lp mong, chu yu dung lam tm lp rt gia tr. losilic. Ngoai ra trong a con cha mt t hat set va thach anh. -atrepencungrtgingiatomit,m hat set, co mau trng, o hay en, rt nhe, o = 500 1200 kg/m3.iatomitvatrepen hoat tnh chu nc cho cac cht kt dnh v c. 4. A 8|N CH1|. C |M H- Khi gp tac dung cua nhit cao tch ba bin cht. - Cn c vao iu kin sinh thanh, chia a bin cht thanh 2 loai: a bin cht khu vc va a bin cht tip xuc. bin i tnh cht sinh ra - a bin chdung cua ap sut ln. - a bin cht tip xuc: c tao thanh t a trm tch b bin cht do tac dung cua nhit cao. ||. CAC LOA| A 8|N CH11HUONG GP: a. a gnai (phin ma): ctaothanhtgranit,ditacdungcuaaplccaogranittaikttinhcht. Trong xy dng a phin ma c dung lam tm p long b knh, lat va he. b. a hoa: - c tao thanh do ssut ln. a hoa bao gm nhng tinh th ln hay nho cua canxit, lin kt vi nhau rt chc ma khng cn cht ximng hoa. - a hoa co nhinhng mach nho va vn hoa, cng chu nen gii han thng la 1200daN/cm2, i khi n 3000daN/cm2. a hoa d ca thanh tm mong va d mai nhn va anh bong- a hoa dung tcu thang, lat san nha. a hoa co nhiu Thai Nguyn, Thanh Hoa. c. a quczit: - c tao thanh t sa thach thach anh tai kt tinh co mau trnng chng phongg. dung xy gi ta cu va tru cu, san xut tm p du ng, lam nguyn liu san xut vt lid. Dip- Co cu tao dang phin, do t set b bin cht di tac dung cua ap lc ln. Dip thach set co mau xam sm, co tnh n nh i vi khng kh, khng b nc pha hoai va Giao an Vt liu xy dngTrang 28 CHNG III VRT LlEU UM XRT 0UNU . KHA| N|M vA PHN LOA| |. KHA| N|M: -Vtliugmxydngnhgach,ngoilanhngvtliuanhntao,csan xut t t set bng cach tao hnh va nung nhit cao (qua qua trnh gia cng c hoc va gia cng nhit). Do qua trnh thay i ly, hoa trong khi nung nn vt liu nung co tnh cht khac hn vi nguyn liu ban u. -Trongxydng,vtliugmcdungtrongnhiuchititktcucuacng trnh t khi xy, lat nn, p tng nha n ct liu rng (keramzit) cho loai btng nhe. Ngoai ra, cac san phm s v sinh la nhng vt liu khng th thiu c trong xy dng. Cac san phm gm bn axit, bn nhit c dung nhiu trong cng nghip hoa hoc, luyn h c kim va cac ngan ng nghip khac. nh thp. Song vt liu gm vn con nhng han d v, khng phu hp vi thi cng hin ai:kh ndintchthicng,tnthi gian. V n tch canh tac nng nghip, gy nhim ||. PHoaivatnhcht.phnloai chung,- Gm rng: co hut nc Hp > 5% nh gach xy cac loai, ngoi, gach la nem. nungcao,thngcocutruchatmn,sanxutphctapnh gach trang tr, s v sinh. -uimchnhcuavtliugmlacocngtngicao,bntrongmi trng, d tao ra nhiu hnh dang khac nhau va nhiu san phm khac nhau, cng ngh san o, gia tha xut n gian, nguyn liu sn cch la tng i nng ( ln), d hut nc, gion,aquatrnhthicng,t ocgiihoavatnghoic xy dng cac lo nung thu cng lam mt dimi trng. N LOA| : Sanphmgmxydngrtadangvchungl ngi ta cn c vao cac c s sau : dung:. Duo voc fnh nng xy - Vt liu xy: cac loai gach c, gach l. - Vt liu lp: cac loai ngoi. n, lat ng, lat va he.- Vt liu lat: tm lat n- Vt liu p: p tng nha, p cu thang, p trang tr. - San phm ky thut v sinh: chu ra, bn tm. - San phm cach nhit, cach m: cac loai gm xp. - San phm chu la: gach samt, gach inat. 2. Duo voc d huf nuoc: - Gm c: co hut nc Hp 5% nh gach lat nn, lat ng, lat knh mang. 3. Duo voc nh|f d nung: - Gm th: nhit nung thp, thng co cu truc hat ln, san xut n gian nh gach ngoi, tm lat, ng nc. -Gmtin:nhit Giao an Vt liu xy dngTrang 29 2. N. 1honi, sy va nung. Khi ham lng SiOqua nhiu th t setng l Ophn th yu trong t set co tac dung ha nhit nung. Khi ham lng t set con co mt s tap cht khac, nu la MgO, CaO th cn phai han ch . 2. 1hont la cac khoang deo do penspat phong phugiht v c va hu c khac nh: mica, thach anh, hp cht c ap cht hu c n, bitum. Cac tap cht noi trn u anh hng n tnh cht cua t set. GUN L|U CHU U 5AN XU1 v1 L|U GM - 1 51 |. 1HANH PHN KHOANG HOA: - Nguyn liu chnh ch tao vt liu gm la t set nhng co th pha thm phu gia cai tin cng ngh san xut va iu chnh mt s tnh cht. h phn hco hcc: -SiO2:ylathanhphnquantrongcuatset,chuyunmtrongcackhoang deo va mt b phn la SiO2 t do nm dang sa thach thach anh, opan, canxedoan. SiO2 lathanhphnquytnhtnhchtsanphm,nhtlacngvaquytnhkhanng chng co cua t set trong qua trnh ph2 se kem deo, khi SiO2 qua t th cng san phm thp. - Al2O3 : la thanh phn quan trong, chu yu la nm trong khoang deo. Al2O3 quyt nh tnh deo cho t set va tnh chu la cho san phm. Khi ham lng Al2O3 tng th tnh deocuatsettng,tnhchulatngnhngnhitnungcaohn.KhihamlA2 3qua t th t set kem deo khng tao hnh c, khi Al2O3 qua nhiu th t set tr nn qua deo, san phm se b bin dang. - Fe O : la thanh 2 3 Fe2O3 nhiu th nhit nung thp nhng cht lng san phm khng cao.i vi t set san xut thng (gach, ngoi), yu cu ham lng Fe2O3 nho hn 7%, i vi t set san xut gm, s ham lng Fe2O3 phai bng 0 ( san phm am bao co mau trng). Ngoai ra trong v no gy n th tch lam nt san phmh phn khcong: * Cac khoang deo: Thanh phn chu yu cua t sehoataothanh.olacacalumsilicatngmnccocngthc: mAl2O3.nSiO2.pH2O.Tuytheoiukincuatngmitrngmacackhoangtaoraco thanh phn khac nhau : + Khoang caolinit: Al2O3.2SiO2.2H2O+ Khoang halosit: Al O .2SiO .4H O2 3 2 2+ Khoang montmorilonit : Al O .4SiO .2H O2 3 2 2- Khoang caolinit co kha nng chu la tt. Khoang montmorilonit co phn tan cao, kha nng hp phu va trng phng ln, co deo, co khi sy va nung cao. V vy t set cha nhiu khoang mntmorilonit thng dung lam phu gia cho t set kem deo,achngthmnc.tsetchchakhoangcaolinitgoilatcaolanh(mau trng). Khoang halosit co tnh cht trung bnh gia hai loai khoang trn.* Cac khoang SiO2 t do: nh sa thach thach anh, opan, canxedoan...Ngoai ra, trong t set con cha cac tap cacbonat (CaCO3, MgCO3), cac hp cht st Fe(OH)3, FeS2, tth dang than bu Giao an Vt liu xy dngTrang 30 -tsetcomauscrtkhacnhau:tmautrng,nu,xanh,xamnmauen. M t se c ta t v c va u c quyt nh. Khi nung ca p ch u c dou sc an p hu th u y tap c t; tuy g oxi san phm co nhi u kha u. Fe2O3 (%10 au sc cua chay ht, t st mat do cao map ch cua su ma hhm pc nhac taht st h ln uc ch u vao Mau sc san phm gm theo ham luong oxit st (Fe2O3) Ham luong ) 0,81,32,74,25,58,5 Mau cua sa m vanghngngnu n phnung trng trng uc vang nhatnhat hhng Thanh phn hoa hoc cua t set dung san xut gach ngoi thng dao ng trong MgOMui kimpham vi nh bang sau: Thanh phn hoa hoc cua dt set san xut gach ngoi binh thuong SiO aO 2Al2O3Fe2O3SiO2 t do C40 0,5 3%1 3%60%8 22%1 7%15 30% 0,5 4,5% ||.PHmm la hat bui ; t0,14 5mm la hat ct set c chia thanh 3 loai: nunglnhn1580oCvathanhphndchaynh 3 nho hn 10%. ay co nhit nung t 1350 1580oC va thanh phn d chay nh CO3. 1nh itacdungcuangoailcvagi N LOA|: . Duo voc |uong ngm sef:- Hat cod 28 %, co 10 15%- t set deo trung bnh: nc yu c- t set kem deo: nc yu cu< 20 % , co 5 7% - Xac nh ch s deo D : D = Wch - Wlv ; % trong o : Wch - m gii han gia trang thai deo va trang thai chay nhao, % Wlv - m gii han giatrang thai don va trang te. Cac bin phap thay i tnh deo: -Muntngonilomit),tngcnggiacngchoc(p,nghin,trn,ngm,u)hoccoth dung phu gia tng deo (n-Ngclai,mungiamdeocothchothmcacphugiatrnhbta,cat, samt; phu gia chay nh bt than, mun ca hoc tng tc gia nhit. c no fh fch cuo df sa. Hin tng: - Trong qua trnh phi, sy va nung, th tch cua t set b giam kem theo cac du Giao an Vt liu xy dngTrang 32 - co la giam kch thc va th tch cua t set khi sy kh (co khng kh) va khi nung (co la). co c tnh bng % so vi kch thc ban u. loai t set, co khi sy dao ng trong khoang t 2 3% n 10 1 ung, thng dao ng mai lp hoc y bng rm, ra, sy bng ng hm. 3. Coct set bay hi, t set b co. - Khi to =20 y, t set tip tuc co vacothgyanhhngnch nhFeOtaorami trng- Khi to = 450 hoa hoc tach ra va t set mt tnh deo do caolinit c init: Al2O3.2SiO2 + 2 H2 O cac phan ng phn giai bt u xay ra:Al2O3.SiO23Al2O3.2SiO2(mulit) i lng th tch cua san phm tng do xut hicnhit13701420oC.Khoangmuliclakhoangchnhrtquan trong v1000oC:mtphnbtuchaylpycacchtrnglamchosan phm c, chc . b. Cac giai oan co:-cokhisylasgiamkchthcdoquatrnhmtnctrongcacngmaoquan, lam giam ap lc mao dn khin cac phn t t xch lai gn nhau. Kt qua t set b co. Tuy thuc vao tng 2 %.- co khi nung chu yu la do cac thanh phn d chay cua t set chay ra, cac hat t set tai cho co xu hng xch lai gn nhau. co t 2 3% tuy thuc vao loai t.- co tng cng cua t set la tng co khi sy va khi ntrong khoang 5 18%. c. Khc phuc:- giam co khi sy thng thng ngi ta trn thm phu gia gy nh bt t set nungnon,btcathocphugiachay.Ngoairachoncbayhittbngcachphi trong nha co phon ung hco |y xoy ro frcng quo frnh nung: - Khi to = 100 130oC: nc t do trong 0 450oC: nc hp thu bay hi, cht hu c chatlngsanphm;Fe2O3chuyntha kh. 550oC: cht hu c chay ht, nc huyn thanh mtacaolAl2O3.2SiO2.2H2Ometa caolimit dang thu hnh - Khi to = 550 880 980C th Al2O3.2SiO2 Al2O3 + 2 SiO2

Al2O3 Al2O3CaCO3CaO + CO2- Khi to =1000 1200 1420oC th cac phan ng kt hp bt u hnh thanh tao ra cac khoang vt chnh cho san phm. Al2O3 +SiO2Al2O3.SiO2(silimanit) - Qua trnh kt khi xay ra, th tch b co, khn pha long. Nhit cang cao s chuyn hoa silimanit thanh mulit cang manh va phanngktthu no hnh thanh nn b khung chu lc cua san phm va lam cho san phm co tnh bn nhit. Trong giai oan u cua vung dung kt nay : +Nhit> Giao an Vt liu xy dngTrang 33 + Khi to = 1050 1450oC: t set at trang thai chay ti han, ngha la tt ca cac b phn d chay a chay ht ra lp y tt ca cac l rng, luc o san phm se c chc nht nhngn dnay goi la hin tng dung kt va nhit o goi la nhit +Nhitl bkhitsetsechaylongra.Hin ng chay va nhit o goi la nhit chay. : t = t0chay - t0 dk = 70 100 0 C f khoc: ng la : vt liu hat(chat0,142mm),cchtaobngcach nghinn xut cac san phm co cht l ng cao 700 750oC h nc hoa hoc. No c dung vi ham lng 30 50% nhm cai thin tnh cht cua 25%. Nu ham lng cua bn nc cua san phm gm. phu gia chay. mun ca, phoi bao, thai phm cua cac x nghip lam giau than a, tro nhit in, ba giy,... khng nhng co tac dung lam tng rng cua gach ma con it ng u hn. cha b bi ang. Hin tng dung kt. nhnnhitdungkt:toan tng o goi la hin tNh vy :tonung = todk toch t set thun li cho qua trnh nung co4. Coc fnh ch- Tnh chu la: do ham lng Al2O3 qui nh - Mau: do ham lng Fe2O3 qui nh. |v. PHU G|A: -Ngoai nguyn liu chnh la t set, ngi ta con pha thm vao t set cac vt liu phu nhm cai thin mt s tnh cht cua t set. Cac vt liu phu thng dugy, phu gia chay va phu gia tng deo, phu gia ha nhit nung va men. . vf ||u gy: - Pha trn vao t set nhm giam deo, giam co khi phi sy va nung. Vt liu gy thng dung la samt, t set mt nc, cat, tro nhit in, x hoat hoa. -Samtlavtliugmdang t set kho chay, chu la, c nung trc nhit nung san phm. No cung co thcchtaotthaiphmgachnungnonla.Samtcotacdungcaithintnhcht khi sy va nung t set. V vy, no c dung sanh gach p, vt liu bn nhit, v.v... -t set nung non c ch tao bng cach nung t set nhit kphi liu khi sy va hnh dang bn ngoai cua gach. -Cat vi c hat 0,5 2mm c dung vi ham lng 10 cat ln hn se lam giam cng va - X hoat hoa (vi c hat n 2mm) la phu gia gy co hiu qua cao. - Tro nhit in va la phu gia gy, va la2. Phu g|o choy vo phu g|o fng dec:-Phu gia chay nhlam cho qua trnh gia cng nh- Phu gia tng deo la t set co deo cao, t bentonit, cung nh cac loai phu gia hoat ng b mt khac. Giao an Vt liu xy dngTrang 34 3. Phu g|o ho nh|f d nung: - Con c goi la cht tr dung co tac dung cai thin qua trnh gia cng nhit cua hit nong chay thp t, pecmatic, sienit, v.v... an phm cao lanh, fenspat, boric, borat (Na2B2O.10H2O), v.v...-Mendungsanhlamenmauhocmen c men uc, men bong hoc men khng bong, men s hoc men sanh v3. GACH 1 51 NUNG |. QUA ln ln, t tht pha soi m gach c. hingnht.Khinhaotrnphaiiu sanphm.Nocotacdunghanhitktkhi,lamtngcngvaccuasan phm. Phu gia ha nhit nung co hai nhom : - Nhom th nht bao gm nhng cht ban thn chung co nnh fenspa-Nhomthhaigmnhngchtbanthnnoconhitnongchaycao,nhng trongquatrnhnungcokhanngkthpvicacthanhphnphiliukhactaora nhng san phm co nhit nong chay th p (canxit, lmit, ...). 4. Men: -Lalpthuytinhlongmong(chiuday0,10,3mm)phulnbmtsanphm gm, khi nung co kha nng bam dnh tt vi san phm. Lp men co tac dung bao v schnglaitacngcuamitrng,tngtnhchngthmvanhiutnhchtkhac, ng thi tng ve m quan cho vt liu gm. -Nhng thanh phn nguyn liu chnh cua men la cat thach anh,mui cua kim loai kim va kim th, oxit ch, oxit xutvtliugmrtadang:cotkhng mau, men trong hoa co loai men trang tr... V vy vic ch tao men la rt phc tap. 1kNH 5AN XU1: Qua trnh san xut gach t set nung bao gm cac bc sau: khai thac nguyn liu nhao trntao hnhphi synungkim tra. . Kho| fhoc nguyn ||u: - Ngi ta khai thac t bng may ao hay thu cng. Cn chu y loai bo 30 40cm ttrngtrotphatrnloaibocorac,rcy,soia,v.v...Thngsanxut1triu vin gach cn khai thac 2000m3 t. t co mau gan ga, vang ocon kin u la- Sau khi khai thac, t set c u trong b co mai lp hoc anh thanh ng ngoai tri. Muc ch u la cho m cua t c ng u, do o deo va co ngot ng u, qua trnh tao hnh d dang va cht lng san phm cao. 2. Nhoc frn: Muc ch la tao c mt h t set ng u v mau sc, m, tnh cht c ly, thanhphnkhoanghoa,chatdtaohnh.Nunhaotrnttthkhugiacngd dang, cht lng gach u. Tuy phng phap san xut gach la kh hay deo ma co thit b nhao luyn khac nhau. *Phng phapdeo:tcnhaitrongmaynhaivasauotrntrongmaytrn vimt1825%chonkhithanhmtk Giao an Vt liu xy dngTrang 35 chnh o hay qua deo. inhaotrn com W = 18 25%, dungmngphaptaohnhkh:tsetsaukhinhaotrncomW=812%, dung m4. Phong. Co th phi gach mc ngoai tri va mt 8 15 ngay. Phi nh vy n liu, thit b nhng tn thi gian va phu thuc vao thi tit. y.Sygachtheo phngncomthpvacacvincombng nhau. Q an : nung trcnunglam ngui. giai oan lam ngui, gach c ngui t t tranh bin dang nhit; khi ra khoi lo khoi thng ra ng khoi chung gia lo. Loai lo nayco deo cho thch hp bng cach thm t set beo hoc bt gach, hoc cat tuy theo t kem de* Phng phap kh: t c nghin mn sau o trn trong may trn vi m t 8 12% cho n khi thanh mt khi ng nht.3. 1oc hnh: Victaohnhthanhgachmcthngccgiihoavicacphngphap sau: * Phng phaptaohnhdeo: tsetsaukhayepLentocolcep30daN/cm2.Phngphapnaycouimladtaohnh, nng xut cao nhng tn nhin liu phi, sy, nung. *Phay ep thuy lc co lc ep t 200 300 daN/cm2. Kch thc san phm chnh xac, c chc cao, t tn nhin liu nhng kho tao hnh. * Phng phap bun nhao: t c trn vi m rt ln thanh bun nhao. Phng phap nay san xut nhng loai san phm hnh dang phc tap. | sy: - Gach uc xong co m cao qua, nu em nung ngay se b cong vnh, nt tach. Do o cn sy hoc phi nc bay hi t t, n khi m cua gach con 5 8% mi c a vao lo nu tn nhi- i vi x nghip ln, ngi ta sy bng ng hm, bung sy hoc phong sy. Thngnhitsyt4090oCvathigiansykhoang23nga phap nay tn nhin liu va thit b may moc nhng t tn thi gian va khng phu thuc va thi tit. 5. Nung: -Gachmctrckhivaolonungcua trnh nung co 3 giai o- giai oan nung trc, gach mc mt nc dn dn, cac cht hu c b chay ht. giai oan nung, cac hat set cng lai, cac oxit kim loai bt u i mau va gach co rut kch thc. , nhit gach t 50 60oC. - Co 2 loai lo nung gach: *Lonunggianoan:nungtngmemt,xongmenaylaidravaxpmemi. Loainaycngsutnho,thngdungchocaclothucngaphng.Chtlnggach khng u . * Lo nung lin tuc: gm co lo Hopman va tuynel. Lo vong Hopman: co hnh bu duc, nhiu bung ngn, mi bung co ca ring ra vao lo, co ca thng nhau va co ca dnuimlahiusutsdungnhitcao:khngkhlanhvaolamnguikhuva nungxong,ngthikhngkhctnongtrckhivaokhunung;quakhoikhu Giao an Vt liu xy dngTrang 36 nung, khng kh nong lai nung trc gach va tip tuc sy gach mi vao. Nhc im cua loailonaylalakhou,khockhhoakhuravaolo.VitNamthngdunglo dait60150m,dintchsdung c220x105x60mm,gachngcokchthc hep sai s ldai = 5mm, lrng = 3mm, lcao= 2mm. ngphng,khngccong,vnh,stme,maupha pva u, ti ng qua 5 vt nt, mi gqua3vtn dai 2. Cuou rng vinch gn ang b( chiu day > 2/3 chiu rng ) th mu thla mt g nen cua gach tnh theo cng thc : Hopma , chiu dai vong lo thng 200m. gckhhoartcao,lonLotuynel:khannthng2 la 3,5 5,5m . Lo gm 3 khu: nung trc, nung, lam ngui. Thi gian nung nhanh hn lo Hopman, iu kin lam vic c cai thin, lo d dang t ng hoa va co th dung nhin liu rn hoc long. ||. CAC 1NH CH1 vA U CU K 1HU1: . Hnh dong, kch fhuoc : TCVN 1451-1998 -Gachcnendeocokchth220x105x105mm, cho p-Vingachphaib ieng go trong, li lom khng qua 3mm. Trn b mt khngdaikhngqua15mmvasukhngqua1mm,mtbnkhn t,khng qua 10mm, su khng qua 1mm.ng d: P5mm 3mm a. Cng nen:- i vi gach c nen deo (chiu day 85% lot qua sang 0,08mm. - Cac ch tiu c ban anh gia chtnh the 31-1989. uc vabt ngh i hydraSan lng vi va h ng CaO cao, n 4. Hom |uong hof suong: a. Khai nim: -Hat sng la nhng hat vi cha c tg , non la hoc ba th- Ham lng hat sng la ty l v khi lng hat sng so vi khi lng vi sng (cac hat con lai trn sang 0,63mm), tnh bng %. Cn200gvisngttrn sang em ra sach, sy kh, cn va tnh ty l. 5. m|n cuo bf v| sng: - Bt vi sng cang mn cang tt v no thuy hoa nhanhnhit ti va tc ti lnsan-anhgiamn,dungphngphapsangqua2sang0,63mmvasang 0,08mmlng cua vi c quy o TCVN 22 Vi c viinV t Tn ch tiu L IL ILo ILo Lo IIoaioai I ai II ai Iai 1. Tc ti vi, phut a. Ti nhanh, khng ln hn b. Ti trung bnh, khng ln hn c. Ti chm, ln hn 3.mlng(CaO+MgO)hoat 4.i,l/kg,khng ng ti c cua vi ng ln hn 008 7. m, %, khng ln hn 20 88 2,4 2 10 - 20 80 2,0 2 10 - 20 70 1,6 2 10 - 67 6 - 6 60 8 - 6 2. Ham lng MgO, %, khng ln hn Tnghatnh,%, khng nho hn nhuyncuavitnho hn 5. Ham lng hat khcuc, %, khng ln hn 6. mn cua vi bt, %, kh - Trn sang 0,063 - Trn sang 0, 10 20 5 5 10 20 5 7 10 20 5 10 - - - - - - - - - - - - Giao an Vtliu xy dngTrang102 v||. CNG DUNG vA 8AO QUAN: . Cng dung: -Trongxydngvidungsanxutvaxy,vatratchocacbphncng trnh trn kh, co yu cu chu lc khng cao lm. iraviconcdungsanxutgachsilicathocquettrn,quettng . 8ocn phai c ngm trong h co lp cat hoc nc phu ln trn co b day 0-20cm ngn can vi tac dung vi CO2 hoa a (tao CaCO3)cht lng giam, t deo va lin kt kem. 3. v| 1HU nhng co kha nng rn trong khng kh ma c c san xut t a macn (a vi cha 6-20% tap nhit 900-1100oC. ng = 1 : 3,2 t kh + vi kh i va kt hp sau : H2O 2O3 + 2SiO2 + 2H2O n MgCO3 th trong thanh phn vi thuy co MgO : CaO + Al2O3CaO.Al2O3(CA) CaO + Fe2O3CaO.Fe2O3(CF) -Ngoatrang tr va bao v vt liu bn trong. 2quon: - Vi vi cuc nn ti ngay hoc nghin mn cho vao bao, khng nn d tr lu. - Vi nhuy1 |. KHA| N|M vA NGUN 1C 5AN XU1: . Kho| n|m: -Vi thuy la cht kt dnh v c khngcon co kha nng rn chc trong ncht set phn b u)2. Nguyn fc son xuf: a. Phi liu: Phng phap phi liu: ty l t set : vi st set t + vi t t set t + vi kh t set kh + vi t t seSau khi phi liu ong thanh vin ri em nung. b. Nung: Qua trnh nung se xay ra cac phan ng phn giaPhan ng phn giai : CaCO3CaO + CO2Ca(OH)2CaO + Al2O3.2SiO2.2H2O Co500 Al2O3.2SiO2 + 2H2O Al2O3.2SiO2.2H2O Co800 AlNutrong a vi co lMgCO3 = MgO + CO2Phan ng kt hp : 2CaO + SiO22CaO.SiO2(C2S) 2CaO + Fe2O3CaO.Fe2O3(C2F) Giao an Vtliu xy dngTrang103 -Nh vy, sau khi nung thanh phn vi thuy gm co : C2S, C2F, CA, CF, CaO va MgO. Nh co khoang C2S, C2F, CA va CF ma vi thuy rn c trong mi trng nc. Thanh phn CaO va MgO ch lam cho vi thuy d ti hn. c. Ta vi thuy: Saukhinungchovithuyhutmngoaikhngkhtarathanhbthocphun vao vi thuy t 15-20% nc. ||. QUA 1kNH kN CHC CUA v| 1HU: -V vi thuy co cha cac loai khoang va CaO, MgO nn s rn chc cua vi thuy bao gm hai qua trnh : - Qua trnh rn chc cua vi khng kh : + Qua trnh hyrxit kt tinh + Qua trnh cacbonat hoa -QuatrnhrnchccuacackhoangC2S,C2F,CA,CF:traiqua3giaioanhoa tan, hoa keo va kt tinh tng t nh ximng (hoc ky trong bai ximng) |||. CAC 1NH CH1 CO L CUA v| 1HU: . Kh| |uong r|ng, kh| |uong fh fch: Khilngring:a=22003000kg/m3,xacnhbngphngphapvtliu chim ch cht long. Khi lng th tch: o = 500 800 kg/m3, xac nh bng phng phap ng. 2. m|n: Dung phng phap sang qua 2 sang 0,63mm va 0,08mm. Yu cu : + 100% lot qua sang 0,63mm+ 85% lot qua sang 0,08mm mn cang cao th qua trnh cng rn xay ra cang nhanh, trit , cng chu lc tt. 3. hcof fnh: hoat tnh la ch tiu anh gia kha nng rn trong nc cua vi thuy manh hay yu va c anh gia bng mun hoat tnh Mht. % % %3 2 3 2 2O Fe O Al SiOMht+ +=% CaOc cang manh. Quy nh: (Vi rn trong khng kh co M> 9,0). aohnvikhngkhnhngthphnximng Pooclng va c anh gia thng qua Rn. Mcang nho th kha nng rn trong nht- Vi thuy loai manh:M= 1,7 4,5ht- Vi thuy loai yu:Mht = 4,5 9,0 ht4. Cuong d: Khanngchulccuavithuyc Giao an Vtliu xy dngTrang104 Trn900gbtvithuyvi2700gcat(tyl1:3)va360mlncucmulp phng7,07cm.Dngh7ngaytrongkhngkh,21ngaytrongnciukintiu chun ri th cng chu nen. Yu cu :Rn = 20 50 daN/cm2

|v. CNG DUNG vA 8AO QUAN: . Cng dung: -Vi thuy c dung san xut va xy, va trat, btng mac thp. -Trc khi dung trong nc phai vi thuy rn trong khng kh 35 ngay (nu la vithuymanh)hoc23tun(nulavithuyyu),sauomichotipxucvinc nhm muc ch cho CaO t do rn theo ng cacbonat hoa. 2. 8oc quon: Vithuyphaicongthanhbaokn,nikhrao,khngdtrlunh ximng tranh cho vi thuy hut m lam giam cng . 4. X|MNG POOCLNG |. KHA| N|M: -Ximngpooclnglachtktdnhvcrntrongnc,sanxutbngphng phap nung hn hp a vi va t set a phi hp theo mt ty l hp ly n nhit nong chaytaothanhclinke,emclinkenghinnhovi35%thachcao.Thachcaocotac dung iu chnh tc ngng kt cua ximng cho phu hp vi thi gian thi cng. - Trong qua trnh san xut co th pha thm phu gia hoat tnh (< 15%) cai thin mt s tnh cht hoc phu gia tr (< 10%) tng san lng ximng. -XimngpooclnglaCKDVCcdungnhiutrongxydngvconhiuu im:cngcao,bntrongmitrng,rnchctnginhanh,chulakhatt, nguyn liu san xut co sn va gia thanh re. ||. 1HANH PHN HOA HOC vA NGUN L|U 5AN XU1: . 1honh phn hco hcc: a. Ham lng: Mun cho ximng am bao cht lng thanh phn hoa hoc cua ximng thng la : CaO:63 66% SiO2:21 24% Al2O3:4 8% Fe2O3:2 4% -Ngoai ra con mt t cac tap cht nh MgO, CaO dang hat gia la gy mt n nh th tch nn cn phai han ch MgO:< 4,5% SO3: 7mmlam lai vi N > Nb

c. Cac yu t anh hng: - Thanh phn khoang: nu lng C3A tng th Ntc tng, C2S cn t nc hn. - mn tngNtc tng va ngc lai - Phu gia : nu ximng co phu gia v c hoat tnh th Ntc = 32 37%, nu la phu gia tng deo th lng nc se giam xung. d. Y ngha: Ntc khng phai la mt ch tiu anh gia cht lng cua ximng nhng s dung no xacnhcacchtiukhacnh:thigianngngkt,nnhthtch,cng ximng theo phng phap nhanh. 5. 1ho| g|on n|nh kf: a. Khai nim: Sau khi trn ximng vi nc, h ximng mt dn tnh deo, ngay cang c st lai, nhng cha co kha nng chu lc, th goi la ngng kt. Thi gian ninh kt cua ximng chia lam hai giai oan: thi gian bt u ngng kt va thi gian kt thuc ngng kt. Thi gian bt u ngng kt: la khoang thi gian (phut, gi) tnh t luc bt u trn ximng vi nc cho n khi h ximng mt tnh deo; trong th nghim thi gian nay ng vi luc kim Vica 1 cm cach ay 3 5mm. Thigianktthucngngkt:lakhoangthigian(phut,gi)tnhtlucbtu trn ximng vi nc cho n khi h ximng hnh thanh cac tinh th, h cng lai va bt u co cng ; trong th nghim thi gian nay ng vi luc kim Vica 5 khng lai vt trn mt h ximng. b. Cach xac nh: Trnximngvilngnctiuchunritaomunhkhixacnhnctiu chun. Thay kim Vica 10 bng kim Vica 1 va lp thm mt i trong. xac nh thi gian bt u ngng kt c sau 5 phut ta tha kim mt ln trong 30 giy cho n khi cm su cua kim cach ay t 3 5mm. Sau thi gian bt u ninh kt, thay kim 5 va c 15 phut ta tha kim mt ln trong 30 giy cho n khi kim Vica 5 khng lai vt trn mt h ximng, xac nh thi gian kt thuc ngng kt. Yu cu khoang cach gia hai im tha kim khng nho hn 10mm. c. Cac yu t anh hng n thi gian ninh kt: - Thanh phn khoang cua ximng: nu ham lng cac khoang C3A, C3S nhiu th thigianngngktgiamvtcthuyhoacuaximngtngnhanh,nuhamlng khoang C2S nhiu th thi gian ngng kt giam v tc thuy hoa cua C2S chm. Giao an Vtliu xy dngTrang117 - mn tng th thi gian ngng kt giam v khi o mc thuy hoa cua ximng cao va tc thuy hoa nhanh. - Nhit va m mi trng: khi nhit tng, m cua mi trng giam th thi gian ngng kt cung giam. - Thi gian ngng kt cua ximng se tng hoc giam nu ta thm vao ximng phu gia keo dai hoc rut ngn thi gian ngng kt. d. Y ngha: Thigianngngktlamtchtiukythutquantrongcuaximng,giupbtr thigianthicnghp ly.Nuximngbtungngktquasm,ngoaihintrngse khng kp thi gian thi cng. Ngc lai, nu ximng ngng kt chm th sau khi thi cng phaitnthigianchithaovankhun,lamgiamtcthicng,giamhiusuts dung van khun va thi gian xut xng cac cu kin b chm lai. Do o quy pham a quy nh ximng pooclng phai co thi gian bt u ngng kt khng sm qua 45 phut va kt thuc ngng kt khng chm qua 10 gi. e. Cac phu gia thay i thi gian ninh kt: - Phu gia keo dai thi gian ngng kt: clinke ximng sau khi nghin thanh bt, nu trn vi nc se ngng kt rt nhanh. V vy, mun keo dai thi gian ngng kt cho phu hpviyucuquypham,ngitacntrnthmvaoclinkeximngathachcao CaSO4.2H2O va nghin ln. C3A + CaSO4.2H2O + H2O 3CaO.Al2O3.3CaSO4.32H2O Khoangnaytrongmitrngconngaxitsekhngtan,ngncankhngcho khoangC3Sthuyhoannkeodaithigianngngkt.Tuynhincnchuykhinghin ln,nhitsanphmximngkhngccaoqua,maphaikhngchvaokhoang 110oC la cung, nu khng thach cao sng CaSO4.2H2O d co kha nng mt b phn hay toan b bin thanh CaSO4.0,5H2O va se lai rut ngn thi gian ngng kt. - Ngoai ra, ta co th trn vao clinke ximng cac mui gc nitrat NO3-Ca(OH)2 + NO3-Ca(NO3)2 -Ca(NO3)2lamuiinlymanhlamchonngionCa2+tng,hanchtc thuy hoa cua cac khoang C3S va C2S keo dai thi gian ngng kt. Phugiarutngnthigianninhkt:trnthmvaoclinkeximngcacmui cacbonat kim: Ca2++CO32-CaCO3

- CaCO3 kt tua lam giam nng ion Ca2+ nn y nhanh tc thuy hoa cua cac khoang C3S va C2S rut ngn thi gian ngng kt. 6. 1nh n d|nh fh fch: a. Hin tng: Trongquatrnhngngktvarnchc,thtchcuavaximngthngbini. Trng hp co s bin i qua ln hoc khng u thng gy nn cac vt nt bn trong cu kin. Hin tng o goi la mt n nh th tch. Giao an Vtliu xy dngTrang118 b. Nguyn nhn: -Dophiliukhngunghaynungluynkhngatlamximngtharamt lngCaOvaMgOtdo,cbitlanhngloaiximngtohathocnghinxongdung ngay ma khng u thi gian trong kho cho CaO va MgO ta ht, thng co tnh n nh kem. S d nh vy la v sau khi ximng a ninh kt xong, cac cht CaO va MgO t do mi bt u thuy hoa, n th tch lam cho ximng kem n nh th tch. -Nu ham lng SO3trongximngquanhiusoviquynhthsexayraphan ng vi Ca(OH)2 va C3A thanh ra mui 3CaO.Al2O3.3CaSO4.32H2O n th tch va cung lam cho ximng kem n nh. -Mtkhac,nulngncsdungquanhiucunggyhintngcochoa ximng cung nh btng va va. c. Cach xac nh Phng phap Lsatlie. 7. Cucng d vo moc x|mng: a. Khai nim: - Cng R la kha nng ln nht cua a ximng chng lai s pha hoai gy ra di tac dung cua tai trong.- Cng tiu chun Rt/c la cng cua a ximng khi mu co hnh dang kch thcchun,cchtaovadnghtrongiukintiuchunvathnghimtheo phng phap chun tui 28 ngay. Hnh dang, kch thc chun: mu hnh dm kch thc 4x4x16cm Ch tao: ximng + cat tiu chun, khun thep, uc bng may gin Dng h: 1 ngay trong khun mi trng nhit 271oC, m khng nho hn 90%, 27 ngay sau trong nc nhit 271oC - Mac ximng la ai lng khng th nguyn do nha nc quy nh da vao cng tiu chun cua ximng. Theo cng chu lc, ximng pooclng gm cac mac sau : PC30, PC40, PC50. Trong o : PC la ky hiu cho ximng pooclng (Portland Cement; cac tr s 30, 40, 50 la gii han bn nen sau 28 ngay tnh bng N/mm2, xac nh theo TCVN 6016 - 1995. - Trong qua trnh vn chuyn va ct gi, ximng hut m dn dn von cuc, cng giam i, do o trc khi s dung ximng nht thit phai th lai cng va s dung no theo kt qua kim tra ch khng da vao mac ghi trn bao. b. Cach xac nh: Ta co th xac nh cng ximng theo 2 phng phap sau: phng phap mm, phng phap nhanh (TCVN 6016 - 1995). * Xac nh mac ximng theo phng phap mm- Cat tiu chun: ham lng SiO2 >96%, ng knh hat d = 0,14 2,00mm, ham lng set < 1%, Giao an Vtliu xy dngTrang119 -Trn hn hp va ximng cat theo ty l 1 : 3, ty l N/X = 0,5. Lng vt liu cho mt me trn la 450 2g ximng, 1350 5g cat, 225 1g nc. * Bc 1 : Ch tao mu Cho nc va ximng vao may trn va trn u trong 1 phut tc chm, tng tc nhanh ng thi cho cat tiu chun chay t t vao ci trn trong thi gian 30 giy. Sauo,chomaytrnthm1phutnarilyhnhpvaximngrachovao3khun kch thc 4x4x16cm, t ln may gin uc 3 mu.Gat bng va mit phng cac b mt mu. *B c 2 : Dng h mu Dng h mu 1 ngay trong khng kh nhit 25oC, m ln hn 90%. Sau othaokhunlymungmvaoncnhit25oCtrong27ngay,mcnctrong thung ngm phai cao hn b mt mu t nht 5cm. *Bc 3 : Kim tra cng -Kim tra cng un trc, cng nen sau. t mu trn hai gi ta cua may th nghim un nh s sau : 10050160 40 S un mu Cng chu un tiu chun la cng chu un trung bnh cua 3 mu th nghim : 3uR =3 2 1 /u u ucR R R + +- Sau khi un gay cac mu, ly nth cng nen nh s sau : h bng cng thc : ta mu em Na mu thMu Tm ep trn Tm ep diF = 4x4cm2 - Cng chu nen cua mu ep tn Giao an Vtliu xy dngTrang120 FPRn =- Cng chu nen tiu chun la cng chu nen trung bnh cua 6 mu th 66 5 4 3 2 1 /n n n n n nc tnR R R R R RR+ + + + +=` Xac nh mac ximng theo phng phap nhanh -Trn200gximngvinctiuchunriuc2khun,mikhun6mulp phng kch thc 2x2x2cm. Dng h mu 20 gi trong khng kh. Sau o, em 6 mu chnghptrong4gihayuntrongncsi30phut,6muconlaitiptucdngh ngchunencuacacmuthtacRmuhp(Rh)va mu kh trongkhngkhmrithcRng hp (Rk/h). - Xac nh ty sh khRR/= mu hp-TraquyphamttacohschuyniK.To,xacnhcngcua ximng theo cng thc : K.RRXM =- Phng phap xac nh cng cua ximng nay co u im la nhanh (khng cn dng h mu trong 28 ngay) nhng co nhc im la kt qua kem chnh xac. c. Cac yu t anh hng: -Cngchulccuaximngphattrintheothigiankhngumagnnh tun theo quy lut logarit. Trong 3 ngay u, cng co th at 40 50%, 7 ngay at 60 70%, nhng ngay sau tc tng cng chm i, n 28 ngay th at c mac. Tuy nhin, trong nhng iu kin thun li, s rn chc cua no co th keo dai vai thang thm ch hang nm, cui cung co th vt gp 2 3 ln cng tai tui 28 ngay. -Cngcuaximngvatcrnchccuanophuthucvaothanhphn khoang cua clinke, mn cua ximng, ty l N/X, iu kin rn chc (nhit va m cua mi trng), thi gian bao quan ximng trong kho. * Thanh phn khoang: tc phat trin cng cua cac khoang rt khac nhau. C3S co tc nhanh nht, sau 7 ngay no at n 70% cng 28 ngay, sau o th chm p lai. Trong thi ky u (n tui 28 ngay), C2S co tc hat trin cng chm (RC2S = 15%RC3S)nhngthikysautcnaytnglnvacothvtcacngcuaC3S. Khoang C3A co cng thp nhng lai phat trin rt nhanh thi ky u. *mn:khimntng(trongkhoang8595%)thcngcuaximng cung tng v mc thuy hoa a c tng ln. Tuy nhin, nu mn qua ln (ln hn 95%) th yu cu nc nhao trn tng, trong qua trnh rn chc nc se bay hi lai cac l rng trong a ximng tng ln nn cng ximng se giam i. Nu mn qua nho (nhohn85%),quatrnhthuyhoacuaximngsexayrakhngtritnncng ximng cung se giam. Khi mn cua ximng cang ln th cng cang giam nu d tr lu v ximng hut m nhiu hn. Giao an Vtliu xy dngTrang121 * Ty l N/X: khi ty l N/X va u qua trnh thuy hoa xay ra hoan toan nn cng cua ximng se tng. Nu ty l N/X qua ln, nc t do se bay hi trong qua trnh rn chc lai cac l rng trong a ximng nn cng cua ximng se thp. Nu ty l N/X qua nho, qua trnh thuy hoa xay ra khng hoan toan nn cng ximng se giam. *iukinrnchc(nhit,mmitrng):coanhhngnquatrnh rnchccuaaximngvgiaioanucuaquatrnhrnchclathuyhoa.nhit di0oCphanngthuyhoasednglai,nhit515oCquatrnhthuyhoaxayra chm,nhit2025oCquatrnhthuyhoaxayrabnhthng.nhitlnhn 75oCvaiukinbaohoahinc,tcphattrincngcuaximngnhanh. hitiu n ximng trong kho cang dai th cng cua ximng cang miducobaoquantrongi ukinkhhu a nc ta sau 3 thangiam i 30 40%.- Cac ch tiu c ly chu yu cua ximng pooclng c quy nh trong TCVN 2682 - 1999 nh bang di cua ximng poocl Mac ximng n 175200oCvaiukinbaohoahinc(mitrngoctocla),tcphat trincngcuaximngrtnhanh.Khidng hmutrongiu kinoctocla,cng cua ximng sau 4 gi co th at n cng cua ximng sau 28 ngay dng h kin thng thng. * Thi gian bao quagia ukinttnht.Thngthngtrongicng giam i 15 20%, sau mt nm g cuy: Cac ch tiu co ly ngTn ch tiu PC30PC40PC50 1 - Gii han bn nen, N/mm2; khng nho hn - Sau 3 ngay - Sau 28 ngay ,ln 3 - - Thi gian bt u ninh kt, phut, khng sm hn hut, khng mun hn 4- ch,xacnhtheophngphap L30 2700 45 375 10 40 2700 45 375 10 50 2800 45 375 10 2 - nghin mn - Phn con lai trn sang 0,08mm, %, nho hn -TydinxacnhtheophngphapBlaine,cm2/ghn Thi gian ninh kt 16 15 21 15 31 12 - Thi gian kt thuc ninh kt, pnnhthtsatlie, mm, khng ln hn 8. Nh|f fhuy hco cuo x|mng: a. Khai nim: -Trongquatrnhthuyhoacuaximngsinhracacsanphmmi,cacthanh hnkhoangtngtacvincvaphatsinhramtlngnhit.Lngnhitnayln trong thi gian u, sau o giam dn va tt hn khi phan ng thuy hoa kt thuc. p Giao an Vtliu xy dngTrang122 n v khi lng ximng. khi txeo cal/ Luonghat ra sau thoi gian - Nhit thuy hoa la lng nhit toa ra trong qua trnh ninh kt rn chc cua mt Luong nhit phat ra sau huy hoa( tnh thcac thanh phn khoang vt cua imng gam ) nhit pTn thanh phn khoang vt 3y7y3 t gnga ngay28 nga han 3CaO.SiO2

-2CaO.SiO2

3CaO.Al2O3

141 56,8 110 158 - 209 171,4 222 214,5 97 15 25 116 40 124 44 5CaO.3Al2O3 4CaO.Al2O3. Fe2O3 22609099 b. Cac yu t anh hng Lng nhit phat ra cua ximng nhiu hay t phu thuc vao thanh phn khoang, mn cua hat ximng, thi gian bao quan ximng. Nhng thanh phn C3A, C3S phat nhit uvanhanh,concacthanhphn C2S,C4AF phatnhit tng itvachmtrongthi co mn cang ln th phat nhit cang nhiu v qua trnh thuy hoa xay n len ep, b co ngot do mt nc gy nn ng sut nhit phat sinh vt nt trong hi btng. V vy, giam nhit cho cac cng trnh btng co th tch ln, ngoai cac hng loai ximng toa caccngtrnhxydngdungximngnmtrongmitrngnc ng dn, cng giam va co dnNguyn nhn chu yu gy ra hin tng n mon la : gian u. Ximngra nhanh va trit . Nu thi gian bao quan ximng lu th nhit thuy hoa se nho i v khi o ximng a hut m trong khng kh. c.Y ngha Lngnhitphatracolichovicthicngbtngkhitrilanh,hockhimun btngrnnhanh,cngcaovnokchthchquatrnhthuyhoaxayranhanhhn. Ngc lai, khi tri nong va nht la khi btng co th tch ln th nhit thuy hoa phat ra lam cho phn btng bn trong co xu hng n ra, trong khi o phn btng bn ngoai b van khukbin phap phn oan thi cng va toa nhit thng dung, cn chu y nt nhit. v||. H|N 1UONG N MON X|MNG vA CAC 8|N PHAP PHONG: . H|n fuong n mcn: Trongthctsau mt thi gian lu th b mt cua no se b r, rng tthn kt cu b pha v. 2. Nguyn nhn: Giao an Vtliu xy dngTrang123 - Trong ximng co mt s thanh phn khoang, nht la Ca(OH)2 d b hoa tan va ra tri lam cho kt cu cua btng va va b rng, do o cng giam thp (xm thc hoa tan). - Khi gp mt s hoa cht (nh cac cht axit va mui ...) mt s thanh phn cua a ximng dnh t (xm thc trao i) hoctao ra nhng cht mi co th tch ln hn trc, gy ra ni a (xm thc banh trng th tch). thng tn tai ng thi va anh hng ln nhau. ay i, th kt cu cua cng cua nc (biu th ngCa(OH)2nhtnh.Vdu uCaOdidang ,nnggiamxungth 2O se b phn giai theo phan ng : H)2it yu): -NcthinnhinthngcolnhocthocnhiuCO2didangH2CO3.Nu ng Ca(OH)2 + CO2 CaCO3 + H2O 20mg/l, se sinh ra cac phan ng co)2 + CO2 CaCO3 + H2O sinhraphannghoahoc,taoranhngchtmidtantrongnc,khng kng sut pha hoai btng va vNhng nguyn nhn trn y 3. Coc dong n mcn chu yu: a. n mon trong nc ngot: -NcngotlamhoatanCa(OH)2doCaOtdotrongximnghocdoC3S,C2S thuyhoasinhra.TuyhoatancuaCa(OH)2khnglnlmnhngnutraiquanhiu nm tip xuc vi nc hoc nc ngot cua mi trng lun lun tha ximng se b rng i kha nhanh. Khi o, nc lai co kha nng chui vao bn trong hoa tan Ca(OH)2 ri cun i, lam mt tnh dnh kt ni b va lam cho cng ximng giam xung. Hin tng n mon nay cang manh khi gp nc co ap lc. - S hoa tan cua Ca(OH)2 trong nc con phu thuc vao bng ham lng HCO3- ): cng cua nc cang nho th s hoa tan Ca(OH)2 cang tng; nu cng at gia tr thch hp th hoa tan cua Ca(OH)2 giam i, v sinh ra phan ng : Ca(OH)2 + Ca(HCO3)2CaCO3 + 2H2O CaCO3hnhthanh,baophulnktcu,ngncanCa(OH)2tdohoatan.CaCO3 hoa tan t hn Ca(OH)2 100 ln. Mt khac v cac khoang vt sinh ra sau qua trnh thuy hoa cuaximngchcothnnhnhngn2CaO.SiO2.nH2OchtntaivinngCa(OH)2lnhn1,1g/l.NCa(OH)2bncngotmitrnglamchohoatan2CaO.SiO2.nH2CaO.SiO2.nH2OCaO.SiO2.mH2O + Ca(Olam cho cng giam xung va tc pha hoai tng ln. b. n mon trong nc co cha CO2 (di dang ax n CO2 trong nc t th co li la thuc y qua trnh cacbonat hoa : - Tuy nhin, nu nng CO2 trong nc cao qua 15 hai: Ca(OHCaCO3 + CO2 + H2OCa(HCO3)2

Ca(HCO3)2 co hoa tan rt ln nn pha hoai ximng. Giao an Vtliu xy dngTrang124 c. n mon do axit: -Trongcacloaincbnvancthaicngnghipthngcochacacloaiaxit aSO4.32H2O n th tch gp 2 ln. ac ph trng anxi. cha mui khoang khac: bin, nc ngm, 3CaO.Al2O3.3CaSO4.31H2O (mui canit) n manh). Khi nng ion Mg2+ ln hn 3 hoa tan cua Ca(OH)2. Supephotphat la cht xm thc manh do a ximng. Mui nay lai b nc va mui lam ra ra thanh mt dung dch c, nht, au trng, chay t ximng ra ngoai, lam cho a ximng b rng. n mon sunfat lun xay nghip va nc cung gy ra n mon cac cng trnh btng ximng. Cac axit beo khi tac dung nh HCl, H2SO4, v.v... Nhng loai axit nay tac dung vi Ca(OH)2 theo cac phan ng : Ca(OH)2 + 2HClCaCl2 + 2H2O Ca(OH)2 + H2SO4CaSO4.2H2O - Nhng cht mi sinh ra hoc la d tan nh CaCl2, hoc kt tinh va n th tch nh CaSO4.2H2Onnu gy phahoaia ximng. Mtkhac,CaSO4.2H2Oconcokhanng tac dung vi C3AH6 tao thanh khoang 3CaO.Al2O3.3CC an ng trn y con co tac hai xu na la lam cho nng CaO trong mi giamxung,doothucyquatrnhkhngnnhcuacacthanhphnkhaccuaa ximng. Ngoai ra axit co th pha huy ca silicat cd. n mon trong nc bin, nc ngm va nc -n mon manh: gy ra do cac loai mui cha manh trong nc nc cha mui khoang tac dung vi Ca(OH)2

MgCl2 + Ca(OH)2CaCl2 + Mg(OH)2

MgSO4 + Ca(OH)2 + 2H2OCaSO2.2H2O + Mg(OH)2

3CaO + C3A + 31H2O Cht Mg(OH)2 sinh ra la cht kt tua v nh hnh dang ri rac khng dnh kt va khng co cng se b ra tri ra ngoai (n mo500mg/l mi xay ra n mon manh. Cht CaCl2 la mui in ly manh, rt d b hoa tan lam cho a ximng b rng. - n mon phn khoang: la do nitrat amn 2NH4NO3 + Ca(OH)2 + 2H2OCa(NO3)2.4H2O + 2NHNitrat canxi tan rt tt trong nc nn d b ra tri. Phn Kali gy ra n mon a ximng la do lam tng trong thanh phn cua no co cha Ca(H2PO4)2, thach cao va ca axit phophoric. -nmonsufat:s n mon nayxay ra khi hamlngsufatln hn 250mg/l (tnh theo nng ion SO42-).3CaSO4 + C3AH6 + 25H2O3CaO.Al2O3.3CaSO4.32H2OCht 3CaO.Al2O3.3CaSO4.32H2O co tnh n th tch gp 2 ln, gy ra ni ng sut trong mra i vi cac cng trnh ven bin, cng trnh tip xuc vi nc thai cngngm. Nu trong nc co cha Na2SO4 th u tin no tac dung vi vi : Na2SO4 + Ca(OH)2CaSO4 + 2NaOH Sau o, no mi tac dung tip tao thanh etringit. - n mon cua cac cht hu c: trong mi trng nc co mt s sinh vt tit ra cac axit hu c Giao an Vtliu xy dngTrang125 vivigyraratri.Dumovacacsanphmcuano(xng,duhoa,dumazut)se khng co hai cho btng ximng nu chung khng cha cac loai axit hu c va cac cht lu huynh. - n mon do kim co trong a ximng ngay trong long khi btng gia cac phn t vinhau.Banthnclinkelunchamtlngchtkim.Trongkhio,trongctliu btng, c bit la trong cat, lun hay gp hn cht silic v nh hnh. Chung co th tac nglam cho b mt hat ct liu n ra mt ra va co C3A. Nhng cht nay hoc la b hoa tan lam cho a ximng b luynatgiambtcac o lm, th mi thch dung. t phu gia anh n got, t n mon, t ngm axit. b mt ngn cach btng vi mi trng nc bng cac loai vt ha xng, quet thuy tinh long, sn chng thm, boc cac cu kin bng van khun thep hc n mi trng nc, co h thng hut va thoat nc trong cac cng trnh i. dung vi kim cua ximng ngay nhit thh thng vt nt, bac mau. S pha hoai nay co th xay ra khi k t thuc xy dng 10 15 nm. 4. 8|n phop d phcng n mcn chc x|mng: S d ximng b n mon la v trong ban thn ximng co CaO t do, co Ca(OH)2 do C3S thuy hoa sinhrng va nng vi giam xung, hoc la phan ng vi cac axit, cac mui tao ra nhng cht mi d lam cho a ximng b pha hoai hn. V vy, bin phap phong n mon cho ximng gm co : -Thayithanhphnkhoangvtcuaximng,nung thanh phn CaO t do, C3S va C3A xung. Tuy nhin, vic giam thp ham lng C3S lai anh hng n cng cua ximng, cho nn ch nhng ni co yu cu chng n mon cao ma btng khng cn co mac ca- Dung bin phap silicat hoa bng cach trn thm vao ximng nhng chhoat tnh cha nhiu SiO2 v nh hnh tac dung vi Ca(OH)2, C3A cua ximng thnhng hp cht silicat n nh hn. Ca(OH)2 + SiO2 (VH) + H2OmCaO.nSiO2.pH2Okhng taC3AH6 + SiO2 (VH) + H2OmCaO.nAl2O3.pSiO2.rH2Okhng tan - Vi nhng mi trng ma tnh cht n mon a cu th, th ngi ta s dung nhng loai ximng c bit thch hp, nh ximng chng sunfat, ximng chng axit. - Dung bin phap cabonat hoa b mt bng cach trc khi dung trong nc, nncaccukinbngximngtipxucvikhngkhmtthigian(23tun),nhvy Ca(OH)2 se c cacbonat hoa thanh lp vo CaCO3 bao boc cho bn trong kho b hoa tan hn. Tuy nhin, bin phap nay ch ap dung i vi nc n- Tng c cua kt cu btng bng cach han ch lng nc tha trong btng, nh dung phu gia tng deo, dung chn khng hut nc tha sau khi khun va m chc xong, dung bin phap m chc btng bng chn ng. - Tao lp bao vliu c va tr i vi btng nh: quet 2 3 lp nhu tng bitum hoc dung dch bitumpbng vt liu gm. - Cai thi Giao an Vtliu xy dngTrang126 v|||. C 1NH, 8AO QUAN vA 5U DUNG X|MNG POOCLNG . c fnh Ximng pooclnh co cng phat trin tng i nhanh va cao, nhit lng phat mi qua 10 bao. Xp ximng theo th t thi gian dung, ximng co ngay san uttrimng pooclng la cht kt dnh quan trong nht trong vic xy dng cac cng -Tuynhin,khngnnsdungximngpooclngmaccaochocaccngtrnhco th tch ln v nhit lmi trng co tnh (ncbin,ncthaicngnghip),cngtrnhchuaxit,cngtrnhchu hit. Vrnvanghinlncungclinkecuaximng t tnh puzolan va thach cao. Ty l pha trn thng la ximng ra trong qua trnh thuy hoa nhiu hn va khi lng ring cung tng i cao hn so vi nhiu loai ximng khac; trong cac mi trng n mon, ximng pooclng chng thm kem nhng tnh chu la lai tng i kha. 2. 8oc quon Ximng pooclng rt d hut m trong khng kh, ong von thanh cuc, tr nn kem phm cht, cng giam xung va thi gian ninh kt rn chc keo dai. V vy, vn chu yu trong vn chuyn va bao quan trong kho la phai chng m cho ximng. Kho cha ximng phai cao rao, san phai cach mt t 0,5m, phai xp cach tng kho 0,5m vachng khngx cthdungtrc,congaysanxutsauthdungsau.Khngnnximnglu qua 3 thang v cng ximng co th giam n 30% do kh hu nong m cua nc ta. Nu ximng a tn kho lu qua6 thang, cn phai kim tra lai mac trc khi s dung. 3. 5u dung - Xtrnh, c bit la cac cng trnh btng va btng ct thep. Ngi ta dung ximng san xut btng va va dung cho moi cng trnh trn can, trong t, trong nc khng n mon hoctnmon,dung chtaocukin btng vabtngctthep phucvuchoxydng lp ghep. ng toa ra nhiu va khng nn s dung nhngnmonmanh n i nhng loai cng trnh nay cn phai s dung nhng loai ximng c bit. 5. X|MNG POOCLNG PUZOLAN |. KHA| N|M: - Ximng pooclng puzolan la cht kt dnh v c rn trong nc hoc trong mi trngmt,cchtaobngcachtpooclng vi cht phu gia hoapooclng cng vi 20 50% phu gia puzolan va 5% thach cao sng CaSO4.2H2O.- Vit Nam, phu gia puzolan Sn Ty co mau hng nu, do o ximng pooclng puzolan san xut ra cung co mau nu hng. ||. PHU G|A PUZOLAN - Phu gia hoat tnh phuzolan la phu gia khoang vt, thanh phn chu yu la SiO2 v nh hnh va Al2O3 hoat tnh. Ban thn phu gia puzolan khng co kha nng rn chc trong ncnhngtrongmitrngconngvinhtnhthnosetngtacvivitao thanh nhng hp cht mi co kha nng rn chc c trong nc. Giao an Vtliu xy dngTrang127 -Cohailoaiphugiapuzolanlaphugiapuzolanthinnhinvaphugiapuzolan nhntao.PhugiapuzolanthinnhincothanhphnchuyulaSiO2vnhhnh, iO2.nH2Oclytcacsanphmcuanuilanhtronuila,tupnuila,soiabot t nh iatomit, trepen. Phu gia puzolan nhntao g ging nh qua trnh silicatngmnc, a(OH)2.Cackhoangtrncung nh hnh va Al2O3 hoat tnh co trong phu gia puzolan : 2O khi C3A thuy hoa tao ra C3AH6 se tac dung vi SiO2 v nh hnh theo 3CaO. Al2O3.SiO2.nH2O UZOLAN: n pooclngpuzolancokhilngringvakhilngthtchnhohn tmcnghinthximngpooclngpuzolansemnhnximng iu kin bnh thng, ximng pooclng puzolan ninh kt rn chc ng pooclng. Shoc ly t cac loai a trm tch bin chco thanh phn chu yu la SiO2 v nh hnh va Al2O3 hoat tnh. No co trong t set nung non hoc co trong ph thai cng nghip nh x qung, tro nhit in, v.v... |||. QUA 1kNH NGUNG K1 kN CHC: - S rn chc cua ximng pooclng puzolan thi ky u cunrnchccuaximngpooclng,tclacunghnhthanhcacsanphmcacaluminatngmnc,cacferitcanxingmncvaCtrai qua 3 giai oan la hoa tan, hoa keo va kt tinh. Ring Ca(OH)2 mi sinh ra se tac dung vi SiO2 vCa(OH)2 + SiO2 (VH) (0,8 1,5) CaO.SiO2.nHCa(OH)2 + Al2O3 (ht)CaO.Al2O3.nH2O - Ngoai raphan ng : C3AH6 + SiO2 (VH) -Cac khoang mi cung tham gia qua trnh ninh kt theo ba giai oan : hoa tan, hoa keo va kt tinh. |v. CAC 1NH CH1 CUA X|MNG POOCLNG P. Kh| |uong r|ng, kh| |uong fh fch: Xim gximng pooclng,vao khoang : a = 2,8 2,9g/cm3o = 0,8 1,0g/cm32. m|n: Nucungmpooclng. mn c anh gia bng phn trm lng lot qua sang, yu cu v mn gingnhximngpooclngnghala100%lotquasang0,2mmvalnhn85%lotqua sang 0,08mm. 3. Nuoc f|u chun: Vximngpooclngpuzolancomncaohnnnnoyuculngnctiu chunlnhnximngpooclng,thngvaokhoang3040%.Vvy,vicungmt lng nc, btng dung ximng pooclng puzolan thng co sut kem hn. 4. 1ho| g|on n|nh kf: Khi dng h chm hn so vi ximng pooclng trong thi gian u, nhng thi gian v sau tc ninh ktcangnhanhvacothuikpximngpooclngsau28ngay.Khidnghiu kin nhit m, ximng pooclng puzolan ninh kt rn chc nhanh hn xim Giao an Vtliu xy dngTrang128 5. 1nh n d|nh fh fch: Ta a bit ximng pooclng b mt n nh th tch la do tn tai cac hat CaO t do ang hnh th tch cao : CaO (t do) + SiO2 (VH) + nH2O(0,81,5) CaO.SiO2.nH2O ngcuaximngpooclngpuzolanlabancht Z40.TrongoPCPUZlakyhiuchoximngpooclngpuzolan, actrs20,30,40lagiihanbnnencuamuchunsau28ngaymdnghva c tnh bng N/mm2, xac nh theo TCVN 4032 - 1985. -Ximngpooclngpuzolanphaiambaoca N 995 quy Md at gia la. i vi ximng pooclng puzolan, cac hat CaO t do nay se tac dung vi SiO2 v nh hnh tao thanh CaO.SiO2.nH2O co tnh n 6. 1nh cc no fh fch: Ximng pooclng puzolan mn hn, xp hn, cn nhiu nc hn ximng pooclng nn lng nc nhao trn ln dn n co ngot ln hn. 7. Cuong d: -Nudnghiukinbnhthngthtrongthigianu,cngcua ximng pooclng puzlan thp hn cng cua ximng pooclng, nhng cang v sau th cng phat trin cang nhanh co th ui kp hoc ln hn. -Cacyutanhhngncximng (thanh phn khoang, mn, ...) va hoat tnh cua phu gia puzolan. Nu phu gia puzolan cang tinh khit th lng dung se t i va cng a ximng se cao, nu phu gia puzolan kem tinh khit (ham lng SiO2 v nh hnh thp) th lng dung phai nhiu dn n cng a ximng giam xung. -Cnctheobnnen,ximngpooclngpuzolancphnlam3mac: PCPUZ20,PCPUZ30,PCPUccyucu theoTCV 4033-1nh nh bang sau: ucTn ch tiu PCPU20PCPU30PCPU40 Z Z Z1- Gii han bn nen, N/mm2, khng nho hn - Sau 7 ngay m - Sau 28 ngay 2- nghin mn - Phn con lai trn sang co kch thc l g phap - Bt u, phut, khng sm hn t, khng mun hn 20 2600 45 10 10 30 2600 45 10 10 40 2600 45 10 10 0,08mm, %, khng ln hn - B mt ring xac nh theo phnBlaine, cm2/g, khng nho hn 3- Thi gian ninh kt 13 15 18 15 25 15 - Kt thuc, phu4- n nh th tch xac nh theo phng phap Lsatlie, mm, khng ln hn Giao an Vtliu xy dngTrang129 8. Nh|f fhuy hco VhamlngC3Athnnnximngpooclngpuzolankhithuyhoatoaramt lng nhit t hn so vi ximng pooclng. 9. Kho nng chng n mcn -XimngpooclngbnmondocacthanhphnCa(OH)2vaC3AH6.Trong ximng pooclng puzolan, cac thanh phn nay u tac dung vi SiO2 v nh hnh : Ca(OH)2 + SiO2 (VH) (0,8 1,5) CaO.SiO2.nH2O VH)3CaO. Al2O3.SiO2.nH2O cht nay u khng tan nn ximng pooclng puzolan co kha nng chng n on tcacctnhtrnnnximngpooclngpuzolanthngcdungchocac mon va ung cho cacktcubtngkhilnvtbngsutnhit hn ximng ho cac cng trnh cn co ng sm hoc chu tac dung kh m lin tuc, mc nc thay i lin tuc. 8oc quon: Hoan toan ging nh ximng pooclng thng, ximng pooclng puzolan cung cn c bao quan tt chng m, han ch mc giam cng C3AH6 + SiO2 (- Cacm t hn ximng pooclng. v. 5U DUNG vA 8AO QUAN: . 5u dung: -Docngtrnhthngxuyntipxucvincmnvancngotnhhaicang,uthuyn, knh mng, p nc; dung cho cac cng trnh di t, trong nc ngm nnimt;dpooclng. - Tuy nhin, khng nn dung ximng pooclng puzolan cc2. Giao an Vtliu xy dngTrang130 CHNG V t, t ngvi ng gia hp btng va btng . ntrong,csdung t sau : ng vt liu a phng. ho ki btng coong thng. BETNU 0UNU LHRT KET 0lNH V LU . KHA| N|M vA PHN LOA| |. KHA| N|M . Hn hop bfng : -Hn hp btng la mt hn hp bao gm ct liu, cht kt dnh va nc, phu gia (nu co) c nhao trn ng u, co tnh deo , tnh dnhnhng cha rn chc, cha co cng . 2. 8fng : -Btng la loai a nhn tao co cu truc phc tap c tao thanh t 3 thanh phn c ban: *Ctliulanhnghatcat,acohnhdang,kchthc,ctrngbmcng . . . rt khac nhau. *aximngctaothanhtximngtngtacvincvacmthi gi*H thng mao quan, l rng co th cha nc, khng kh va hi nc. 3. vo| frc cuo coc fhonh phn -Ct liu ln la b khung chu lc cua btng sau khi c h ximng gn kt lai. -Ct liu nholam tng c ng thi am bao kha nng chng co cho btng. -Chtktdnhvanclathaan cho rn chc lai. nhphnhoattnhcuabtng,chungtacdunhau tao thanh h cht kt dnh bao boc xung quanh hat ct liu. No lp y l rcachatctliu,ngthiongvaitrolachtbitrntaodeochohnhpbtng. Trongquatrnhngngktrnchc,hchtktdnhlamnhimvulinktcachatct liu lai vi nhau tao thanh mt khi. -Phu gia dung cai thin mt s tnh cht cua hn4. Uu d|m -Btnglamttrongnhngloaivtliuxydngrtquarng rai trong moi lnh vc xy dng v no co nhng tnh cht u vi- Co cng chu nen cao, bn trong mi trng. - Ct liu co th s du- Co th tao hnh d dang c t cu. - D c gii hoa, t ng hoa qua trnh san xut va thi cng. - Co th tao c nhiu loa tnh cht khac nhau. ||. PHN LOA| . 1hec kh| |uong fh fch -Btngcbitnng:o>2500kg/m3,chtaotctliucbit,dungcho nhng kt cu c bit. -Btngnng: =18002500kg/m3,chtaotctliuthng,dungchokt cu chu lc th Giao an Vtliu xy dngTrang131 -Btngnhe:o=5001800kg/m3,trongogmcobtngnhectliurng (nhn tao hay thin nhin), btng t ong (btng kh va btng bot), ch tao t hn hp u t silicat nghin mn va cht tao rng, btng hc ln (khng co t liuo < 500 kg/m3, cung la loai btng t ong va btng ct liu ng. u ng ct liu c bit (chng phong xa, chu nhit, chu axit) mt ng, sn bay, lat va he - Btng dung cho kt cu bao che (thng la btng nhe) -Btngcocngdung hit,btngbnsufat,btng axit, btng chng phong xa 81NG NNG la btng c ch tao t cac vt liu thng thng nh ximng, cat, tkhoangdangthinnhinhaynh