Locked in stresses, creep and dilatancy of rocks, and constitutive equations

~A

between predicted and field equilibrium void ratios for available data on papmrmill sludge. ComBining initial and final effective overburden ~essures with existing mrganlc fr~tions pete.its prediction of void ratios needed for ~ett!ement prediction using conventional soil mechanics theory. 811037 HYPOTHESIS FOR PROGRESSIVE FAILURE IN A ~ARL Cavot~zldis, S; SotiropotLlos, J Geotech Engng Div ASCE, V106, NOT6, June i~0, P6~9-671 Discusses the phenomenon of an i n t e r m ~ a t e ~tep sit~ated between peak and residual in the stress-strain dda~ram. This behaviour was observed in s1~-~ard direct shear and triaxial tests. The iml~licatiOn fc~ the progressive failure of slopes is explored and compared with field evidence. 811038 CYCLIC A ~ STATIC LABORATORY TESTS ON D R ~ N CLAY Andersen~ K H; Pool, J H; Brown, S F J Geotech Engng Div ASCE, VI06, NGT~, May

198o, ~ 9 9 - ~ 9 The pro~ect cam~rised 129 triaxial and 103 simple shear cyclic and static tests on plastic Drammen clay. The clay was preconsolidated above the in-sitU stresses to a vertical preconsolidation stress of ~OOkN/sq m and unloaded to various consolidation stresses in order to produce overconsolidation ratios ranging from 1 to 50. Both static a~d cyclic test results are presented. All cyclic tests w ~ e after termination of cyclic io~ding sUbjected to static loading. Apart from some special tests to study the effect of preshearing, the tests were run under undrained conditions. 811039 EKPERIT..~ENTAL FOLDING OF ROCKS UNDER CONFININ~ PRESSURE, PART 8..=r~CED FOLDING OF UNCONSOLIDATED SAND AND OF LUBRICA'..~O L A Y ~ S OF LIMESTONE AND SANDSTONE Friedman, M; Hugman, R }~ H; Haz*iln, J Geol Soc Am Bull, Part 1, Vgl, N~, May 1980, P307-31~ Reports a study of experimental, faulted, drape folds in veneers of loose, dry, umconsolidated sand and in multilithologlc layered sequences with lubrlca~ed interfaces produced under confining pressures up to 20OMPa at 2~d.-g C. The study addresses the questions of the litholcgic control and the Impor~anae of the process of bed~ir~ plane :~l'p. 8110hO VELOCITY C H A ~ E S ASSOCIATED WITH GENERALIZED TRIAXIAL DEFO~ATION OF PYROPHYLLITE Sond~geld, C H; Gettlr~, I C; Spetzler, H A Pure AI~I Geo;hys, Vll8, N~, 1980, F97~-~89 P and S wave velocities ~ere m e a s ~ e d in dry and we% samples and the variation is discussed in terms of crack development during dilatancy. The orientatlc~ ard development of t h e failure plane was cor~cinuously observed with laser h o l o ~ a l ~ . The study relates %o %he defcrmatlon of fault got~e and gc~e-llke materials. 811041 ED(PER!MENTAL DEFOR4ATION OF PARTIALLY ~ELTED GRANITE ROCKS AT 600-~OOD~ C AND 250MPa CONFINI~D PRESSURE Paquet, J; Francois, P Tec%onOl~hyaics, V68, NI-2, i0 Sept 1980, ~131-1~6

8110h2 LOCKED ROCKS, Tan~ ROck

IN S~I~LEsSES, CREEP A~D DILAT~-NCY OF AND C O N S T . I T I ~ E~AT!ONS T K; Mang, W F Mech, VI3, NI, Aug 1980, I~-22

A micro-theological analysis is presented of the defc~matlon characteristics of rocks based on the min~-sl and crystalline structure of igneOus metamorphic and some sedimentary rocks. The poly~ramalar structure of sandstone-type rocks is also considered. Torsional creep test results on Ichang sandstone are presented and analysed. A new method of testir~ is I r ~ u c e d whereby the sample is subjected to a step wise loadlr~ fumctlon and the def~matlon measured as a f u z ~ t i O ~ of t h e t~me. Tn %hls career creep as a fttr~tlo~ of stress ar~ time can be c~rtalr~ ed from tests on only one sample. A h y ~ e s i s is presented on the origin and formation of 'locked in' stresses. The release of internal strain energy is cOnsiderecl ~Ith reference %o published results, On ~he basis of experimental results and physical reasonir~ cOnstitutive equations are set up, which are three dimensional gmneralisations of the ex~erlmental Grigga equation. 8110~3 DATA AC~JISITION UNIT FOR TRIAXIAL C C ~ S S I O N TEST M E A ~ % V I ~ S AND ALTERNATING SHEAR TEST MEASUREMENTS (IN FRENCH) HulO, Y; Derva~x, 14 Bull Liaison Lab Ponts Chaussees, ~D_07, MayJune 1980, P93-I00 The equipment includes a microprocessor which accepts data from four tri~xial cells (or ~wo triaxial cells and two shear boxes) displaying results in tabular form and also producing punched tape, from which a com!m~cer can supply gral~hical outfit and intrinsic parameters for the soll under test. 811044 ROCK B ~ V I O U R DURING TEE INTERPRETATION OF FRENCH ) B ~ e s t , P; Bergues, Rev Fr Geotech, Ng,

FAILURE: APPLICATION TO TESTS ON T~ICK TUBES (IN J; ~DD'en Minh Duc Nov 1979, I ~ 1 2

DiscUSses the limitations of the Mohr-Coulcmb failure curve and PrOPOses a concept of strain softening be~viour, with a simple r h e o l ~ I c mOdel to explain experimental data. The concepts are used to consider more complex lo~din~ ~rOblems. An urde~round cavity is modelled by ~onsiderir~ %he loading of a thick-walled rock cylinder.

81~0~ ~ i c T ~ o N ~ n

FO~ ~ - m E ~

D!~ON

Boulon, M; Daz~e, F; FlavigDy, E Roy Fr Oeotech, Ng, Nov 1979, F27-~0 An incremental theological model for predictir~ the tundrai~i hehavlo~r of a hcm~ra~o%~ s a t e rated sample of sand or clay is ~n'esented, involving effective stresses amd inte~ranular p r o l ~ i e s . Calculations a r e compared with trlaxial results for sands. A method for estimatir~ pare pressure d~stribution in earth structures with tundralnel co~itlons is developed and ~ 0 field applications are given. 8110~6 STRESS-STRAIN R E ~ ! O N S H I P OF SOILS AS ANISOTROPIC B C ~ E S U N D ~ THREE DIFFERENT PRINCIPAL STRESSES Yoahida, S Soils FoI~, V20~ NT, March 1980, PI-II