Upload
tousif-mahmood
View
63
Download
0
Embed Size (px)
DESCRIPTION
Transportation Engineering, Civil Engineering, Roads and Highways, Particle sieving
Citation preview
3/9/2015 Exp1FlakinessandElongationIndexCivilEngineersPK
http://civilengineerspk.com/transportationengineeringexperiments/exp1flakinessandelongationindex/ 1/7
Exp1FlakinessandElongationIndexFlakinessandElongationIndexEXPERIMENTNO.1:Determinationoftheflakinessandtheelongationindexforthegivenaggregate.sample.SCOPE&SIGNIFICANCE:
This test is used to determine the particle shape of the aggregate and each particle shape beingpreferredunderspecificconditions.
Thesignificanceofflakiness&elongationindexisasfollows
Thedegreeofpackingoftheparticlesofonesizedependsupontheirshape.Duetohighsurfaceareatovolumeratio,theflakyandelongatedparticleslowertheworkabilityofconcretemixes.Flakyandelongatedparticlesareconsideredundesirableforbasecoarseconstructionastheymaycauseweaknesswithpossibilitiesofbrakingdownunderheavyloads.BS1241specifiesaFlakinessindexnotexceeding30%irrespectiveoftheaggregatesize.MaximumpermittedElongatedindexis35,40or45%foraggregatesizes22,1&
3/8.BothFlakinessandElongationtestsarenotapplicabletosizessmallerthen6.3mmi.e.sieve.
CivilEngineersPKEverythingRelatedtoCivilEngineering
Search
Articles Membership BScCivilEngineering Design MScStructuralEngg
Tests/Experiments CV/Resume TOEFL NTSGATPreparation Presentations
Tutorials/Solutions PracticalInfo Jobs Softwares InterviewQuestions
CivilEngineeringProjectTitles CivilEngineeringTopUniversities
ExcelSheets Codes Books HousePlans VideoTutorials ConstructionMachinery
PosterPresentation
http://civilengineerspk.com/http://civilengineerspk.com/poster-presentation/http://civilengineerspk.com/houses-plans/http://civilengineerspk.com/nts-gat-preparation/http://civilengineerspk.com/tutorials/http://civilengineerspk.com/excel-sheets/http://civilengineerspk.com/bsc-civil-engineering/http://civilengineerspk.com/msc-structural-engg/http://civilengineerspk.com/testsexperiments/http://civilengineerspk.com/design/http://civilengineerspk.com/cv-resume/http://civilengineerspk.com/articles/http://civilengineerspk.com/membership/http://civilengineerspk.com/presentations/http://civilengineerspk.com/toefl-ibt-dvd/http://civilengineerspk.com/civil-engineering-top-universities/http://civilengineerspk.com/interview-questions/http://civilengineerspk.com/civil-engineering-jobs/http://civilengineerspk.com/video-tutorials/http://civilengineerspk.com/softwares/http://civilengineerspk.com/practical-info/http://civilengineerspk.com/civil-engineering-project-titles/http://civilengineerspk.com/codes/http://civilengineerspk.com/construction-machinery/http://civilengineerspk.com/booksfiles/
3/9/2015 Exp1FlakinessandElongationIndexCivilEngineersPK
http://civilengineerspk.com/transportationengineeringexperiments/exp1flakinessandelongationindex/ 2/7
RELATEDTHEORY:
SHAPESOFPARTICLES
Theusualshapesoftheparticlesare
1. Rounded(rivergravel)2. Flaky(laminatedrock)3. Elongated4. Angular(crushedrock)
PREFERREDUSEOFEACHSHAPE
Roundedaggregatesare preferred inconcrete roads (rigid pavements) asthe workability of concrete increasesdue to the less friction between thesurfaces.
Angular shapeof the particles isdesirableingranularbasecoarse(flexiblepavement)duetobetterinterlockingandincreasedstability.
FlakyandElongatedparticlesareconsideredasasourceofweakness.
APPARATUS:
Thickness/FlakinessIndexGaugeLength/ElongationIndexGaugeAggregatesampletobetested
FLAKY
A flaky particle is the one whose leastdimension (thickness) is than 0.6 timesthemeansize.
http://civilengineerspk.com/wp-content/uploads/2014/04/images.jpghttp://civilengineerspk.com/wp-content/uploads/2014/04/H-16841.jpg
3/9/2015 Exp1FlakinessandElongationIndexCivilEngineersPK
http://civilengineerspk.com/transportationengineeringexperiments/exp1flakinessandelongationindex/ 3/7
These are the materials of which thethickness is small as compared to theothertwodimensions.Limit of flaky particles in the mixes is30%.Iftheflakyparticlesaregreaterthan30% then the aggregate is consideredundesirablefortheintendeduse.
FLAKINESSINDEX
Itisthepercentagebyweightofflakyparticlesinasample.
Procedure
PerformthesieveanalysisonthegivenaggregatesampleTheaggregatesarethenarrangedintheintoanumberofcloselylimitedparticlesizegroupsstoredortedonthetestsievesintoanumberofcloselylimitedparticlesizegroups22,1&3/8
Eachgroup(fraction) isweighedandtested forthicknessonappropriateopening ofthethicknessgaugebypassingeachparticlethroughslotofspecifiedthicknessalongleastdimension.Theweightofparticlespassingthethicknessgaugeisrecordedforeachfraction.Thisistheweightofflakyparticles.Theflakinessindexiscalculatedbyexpressingtheweightofflakyparticlesasapercentageoftotalweightofthesample.
CalculationforFlakyParticles:
SieveSize WeightRetained
PercentageRetained
WeightofFlakyParticles
IndividualFlakinessIndex
WeightedFlakinessIndex
Passing Retained (gm) (%) (gm) (%) (%)
(in.) (in.)
2 1 2007.8 22.52 80.5 4.01 0.9
1 1 2926.4 32.83 853.1 29.15 9.6
1 2177.7 24.43 585.6 26.89 6.57
1076.2 12.07 291.7 27.1 3.27
8Mar 460.2 5.16 155.5 33.79 1.74
8Mar 211.8 2.38 88.3 41.69 0.99
Pan 53.4 0.6
3/9/2015 Exp1FlakinessandElongationIndexCivilEngineersPK
http://civilengineerspk.com/transportationengineeringexperiments/exp1flakinessandelongationindex/ 4/7
=8913.5 =23.07
ELONGATEDPARTICLES
These arethe particles havinglength considerablylarger than theother two dimensionsand itis theparticlewhosegreaterdimensionis1.8timesitsmeansize.
Limitofelongatedparticlesinthemixesis45%.Thus,iftheelongatedparticlesaregreaterthan45%,thentheaggregateisconsideredundesirablefortheintendeduse.
ELONGATIONINDEX
It isthepercentagebyweightofelongatedparticlesinasample.TheElongatedindexiscalculatedbyexpressingtheweightofElongatedparticlesaspercentageoftotalweightofthesample.
CalculationforElongatedParticles:
SieveSize WeightRetained(gm)
PercentageRetained
WeightofElongatedParticles
IndividualElongationIndex
WeightedElongationIndex
Passing Retained (%) (gm) (%) (%)
(in.) (in.)
2 1 2007.8 22.52 1561.5 77.77 17.52
1 1 2926.4 32.83 950 32.46 10.66
1 2177.7 24.43 1113.8 51.15 12.5
1076.2 12.07 467.5 43.44 5.24
41341 460.2 5.16 185.5 40.31 2.08
41341 211.8 2.38 80.9 38.2 0.91
Pan 53.4 0.6
=8913.5 =48.91
PRECAUTIONS:
1. Whilesieving,caremustbetakenthattheparticlesthatarechockedinthesievemustnobeforceddownintothenextsieve.Suchparticlesshouldbepushedbackintothesamesieve.
2. While placing different fractions on the table, place them some distance apart so that no two
3/9/2015 Exp1FlakinessandElongationIndexCivilEngineersPK
http://civilengineerspk.com/transportationengineeringexperiments/exp1flakinessandelongationindex/ 5/7
9thoughtsonEXP1FLAKINESSANDELONGATIONINDEX
2. While placing different fractions on the table, place them some distance apart so that no twofractionsmaygetmixed.
3. Be careful while selecting the opening of the flakiness and elongation gauges for any particularfraction.FlakinessandElongationIndexFlakinessandElongationIndex
Sharethis:
webpage
onJuly10,2014at20:21said:
ExcellentwebsiteyouhaveherebutIwaswonderingifyouknewofanyforumsthatcoverthesametopicsdiscussedinthisarticle?
IdreallylovetobeapartofgroupwhereIcangetresponsesfromotherexperiencedindividualsthatsharethesameinterest.Ifyouhaveanyrecommendations,pleaseletmeknow.Appreciateit!
CivilEngineersPK
onJuly28,2014at12:38said:
Thanks
Razakhussain
onJuly28,2014at12:18said:
Flanknessandelongationformula
CivilEngineersPK
http://civilengineerspk.wordpress.com/http://civilengineerspk.com/transportation-engineering-experiments/exp-1-flakiness-and-elongation-index/?share=twitter&nb=1http://civilengineerspk.com/transportation-engineering-experiments/exp-1-flakiness-and-elongation-index/?share=facebook&nb=1http://civilengineerspk.com/transportation-engineering-experiments/exp-1-flakiness-and-elongation-index/?share=linkedin&nb=1http://civilengineerspk.com/transportation-engineering-experiments/exp-1-flakiness-and-elongation-index/?share=email&nb=1http://blogspot.co.uk/http://civilengineerspk.wordpress.com/http://civilengineerspk.com/transportation-engineering-experiments/exp-1-flakiness-and-elongation-index/?share=google-plus-1&nb=1http://civilengineerspk.com/transportation-engineering-experiments/exp-1-flakiness-and-elongation-index/?share=pinterest&nb=1
3/9/2015 Exp1FlakinessandElongationIndexCivilEngineersPK
http://civilengineerspk.com/transportationengineeringexperiments/exp1flakinessandelongationindex/ 6/7
onJuly28,2014at12:39said:
Theabovegaugesareusedtoseparatethem
MindFreak
onNovember29,2014at11:36said:
AOA!howmuchsamplehaveyoutakenforthisexperiment?
eldaiab
onDecember23,2014at08:21said:
thelimitsgivenforflakinessandelongationareapplicableforalltypeofroads?
UBAIDAHMAD
onDecember24,2014at09:42said:
pleaseseethecodesforthat
sanjay
onJanuary13,2015at17:42said:
Pleaseprovideexcelcalculationsformat
UBAIDAHMAD
onJanuary14,2015at19:17said:
3/9/2015 Exp1FlakinessandElongationIndexCivilEngineersPK
http://civilengineerspk.com/transportationengineeringexperiments/exp1flakinessandelongationindex/ 7/7
onlyMembershavetheaccess