Sg-X

iaborator', . \ l odc l testing e l d e e p and surface footings in these sands ~as undertaken to e,,aluatc load-settlement beha,.iour-- and bearmg capacity. The easil,, crushable ca!careou~ sand v.as high!3 compressible and sho~ed much io~er bear!ng capaclt,, than the silica sand. Conventional bearing capacity theory is inadequate in the case of calcareous sands.

863094 Surface deformation of layered soil deposits due to extraction of ~,ater Small, J C: Booker. J R Proc 9th Australasian Conjerence on the Mechanics of. Structures and Materials, Sydney, 29-31 Aug 1984 P33-3.Y Puhl Sydney School ol Cirii and .Wining En~n~. !9~'4

( i round subsidence resulting from the pumping of water from aquifers or dewatering of civil engineering projects is often reported. A finite la,,er approach to predict settlement of the surface of horizontally layered soil strata on removal of groundwater is presented. This numerical method does not require large amounts of computer storage and may bc imple- mented on microcomputers.

863095 Theory of heredity of the clayey soil deformations of s,,,,elling Mustafa,,e,.. A A; El-Hans 3 Rouby. %I M Proc 6th Budapest Conference on Soil .Wechanics and Foundation Engineering,Budapest, 2-5 October 1984 P213- 220. Puhl Budapest ,-tkademial Kiado. 1984

The time dependency of the sv, clling of clayey soils has been cxamined using laboratory testing of stiff marine clays at van- ous confining pressures anti water contents, for periods up to 100 days. The results were satisfactorily fitted to the Bohz- mann and Voherra creep t h e o n with a nucleus of the .Abel ty p,:.

863096 Special two-dimensional ~lil consolidation problem Sander. I Proc 6th Budapest Conference on Soil Mechanics and Foundation Engineering,Budapest, 2-5 October 1984 P257- 26-1. Puhl Budapest. .-tka&,miai Kiado. I984

An algorithm is presented for solving soil consolidation under redundant discontinuous boundar,, conditions. A simply com- puterised equation for the time dependency of consolidation is obtained.

863097 Problems of particle delamination in clay s,,,,elling Stepkowska. E T Proc 6th Budapest Conference on Soil Mechanics and Foundation Engineering,Budapest, 2-5 October 1984 P265- 272. Puhl Budapest: 4ka~fl'miai Kiado. I984

The clay-water s.,,stem '*ill tend to an equilibrium state b~ change in its water content, platelet thickness (d). aggregation state or microstructural form Ipara!lel. cluster or floc). Sx~ell- ing can occur b', diffuse layer repulsion or reduction in d Idelaminat ionl Change in d can be efl'ected by mechanical • reatment, or b,, the action of ~ater from the en,,ironment. L'se(ul information concerning s'*elling can be obtained 33 observing the water sorption properties of cla,,s.

863098 Oedometric test ~ith continuous Ioadin~ Za!esky. J: Vanicek. l: S',,.scny. J Proc 6th Budapest Conference on Soil Alechanics and Foundation Engineering,Budapest. 2-5 October 1984 P29-- 30g P;~hl B!al,'pc~" 4;:l,:cnet<u K~ad,,. !9~4

The Czechoslovak code o( practice for ocdon:etric testing is discussed Tx~o oedometer~ are described, one for on-site use. ~ith double drainage and ~tthout pore pressure measurement. the other tSr laboratory c, sc and ~ith pore pressure measure- ment. The constant rate of deformation test ~s t'scd and "he optimum rate has been theoreticalK derived and checked b~ laborator.', testing. The.-~: ,ire recom, naer;dations for the test rate for a number of different softs. The problems of intcrpre- ta'{on of the recorded ~,tluc~ arc considered, and recommcn- dat{ons Ior correction procedures arc madc

Dynamic properties

See a lso ,Y6.¢ 161

8631399 Laboratory-determined transport properties of Berea sandstone Dad.,,, W D: Lin. ~,V Geophysics 150..\5. 31,~: 19~¢5. P-'5--,*'g

Laboratory measurements of electrical resistivity. ~atcr per- meability, and compressional ~a~e ,.elocit3 for both intact and fractured Berea sandstone samples are reported as func- ,.-ix~ns of temperature from 2() to 200 deg C and effecti,,e pres- sure from 2.5 to 50 MPa. These data are used to demonsm~te the possibility of using resisti;ity and xelocit 3 measurements to estimate in situ permeability of a reservoir

86310t) Centrifuge scaling considerations for fluid-particle s.~stems Tan. T S: Scott. R F Geotechnique [35..V-t Dec 1985. P461-47()

The philosophical aspects of the problems of modelling lique- faction and post-liquefaction m a centrifuge are discussed. Some of the current problems in deri'.ing the scaling relations are also treated. An anal3tical study e r a simplified situation is carried out. The problem analysed ~s that of a single particle moving in a fluid. If different fluids are used in the model and prototype, then the difference in densities must also bc accounted for.

863101 Wave-induced stresses in unsaturated submarine sediments Okusa, S Geotechnique [35..V4. Dec 1985. P517-532

A simple method to sol,.e the problem of pore pressure and effective stresses induced by harmonic waves in a poroelastic sediment is presented b3 using Blot's equation and a compati- bility condition for elastic/'>. The sediment is assumed to obey the effective stress principle in the normal definition for satu- rated sediments, although it ma', contain gas bubbles occluded in the pore ~ater. The governing equation is a fourth-order partial differential equation in terms of pore pressure or effec- tive mean normal stress. The solutions contain Skempton's pore pressure coefficient B. Under certain conditions, gas laden marine sediments can liquef3 tinder the trough of a ~a',e. due to wave-induced negatKe effective stresses added to the stress state at rest. The smaller the ~alue of B. the deeper the ~ave-induced l iquefaction

1986 Pergamon Press Ltd. Reproduction not permitt~:d