Dynamic properties of two marine clays

320-74

.2. t,kcory is develo@ for ~ous solids yhlch are either dq or satjlrated by a camp-essible fluid, ard a comxison is made vlth the ?iot theory. yave po?>gatior. results are pesetied, based on data for 3erea ssnistt0r.e. 311075

Ohta, Y; GOto, 6; Yxw.z~.izu,7 Bull Seismol Sot Am, '270, I?_,Feb 19&O, ?36?377 Compressibility,

:ee ?l;o:

swelling

Reports masurenents dmn to a depth of 2-3km in tha area of Tokyo, JaFn.

and consolidation 311076

811031

Ishihara, K; Ysmazaki, v ;011s Foti, WC, Xl, !.%rch :pO, Chzney, P C; I:C~e~s, F; Sheth, F ~eote~h Test ;, ~2, rrj, SeFt 199,

?:58-162

?resetis 3 ?ethcds based on the determination of the 3 pra-eter, which is defined as th.e ratio of the charge in pare ?ater p-essuze in an urdrsirmd triaxial specimen to an incrmep tal charge in %e celi pressure, and m:i be rels:ed to the d-gee of saturation. Dynamic

P&5-55

Reparts the use of a simple shear test device incorparstirg tvo pnexatic cyclic loaders in *do mutually perFendicula_r-horizontal dire~:tions The iced patterns employed -ere rotatior~ in one tyne of test -here cyclic stresses ::ere applied with a pcse difference of 9 degees. In the second type of test, cyclfc stresses xere alternately aslied .Jith I phase difference of 360 SegFees. Relates to the estimation of liquefaction resistance.

properties Classification

and identification

See also: 9111~0 i

.?. ~ firlte elenert, :rocedure for determi~ni:nE reswnse ard liquefaction susceptibliity of a depsit of saturated sznd subjected to au arbitrary bedroc!< acceleration is dwelopsd. The approach ac:ounts for (1) strain hardening ani softeuirg, (2) dexification, (3) hysteretic ati viscous dzqiqg, (b) development of me pessure due to volme change, 3rd (5) consolidation due to internal pressure generation. The results dmonstrate that "site" facct0?.s,such as the shesr resistance of the werburden, seepage corditions, nature 0f the lordirg hi&cay, lsyer thickness, bulk cow pressibility, a115phase cou?li?g, greatly affect the pxe Tessure increase In saturated slllilayers sub>ected to seismic excitation. all073 D?'X.~~l;.fC FY?OPFEE3 OF T'..IO WRINE CLAYS Koutsoftas, D C; Fischc, J A J Gedech Engq Xv AXE; V106, LUX6, June 190, P645-G57 The effects

of stress history

on the dynmic

Toperties of't-70 mrir.e clays have been imestigsted by means of resonant column ani cyclic *ziaxial tests. Tt is shclinthat both the overconsolidation ratio ard the msxuinrsnpast pressure have a significarrt irn'lueroe on the dynamic she= modulus, brrt -re less significant fcr the dzpirg rati0.

The Froblems relating to the classification of mudrocks, ard ln pirticul.sr the role of gr=^in size, 'sre discussed. Cls'ssific?tior.based m silt-clay popxt:ors is more realistic +&an a silt-c12y-sard s-ystem.The grafr. size, as measured in malrccks, is an urxert::ln cuztity ard the use of the gu?stz content is advccated. The n!e+&ai is s=licable in the field u;:rq stanlerd ro3ks of knwn qusr?z content. ;%er.tiOn is drxn to the yoF~+y of fissility, ;ihich.:ay in certair. c%es be shuJn to be due to the rresence of l=_iwe. The formation 3rd preserv&ion of lam?nae r;rovide impx-trrf, sediaentolcgicsl informctior.. duth.