29~
%lons are disctmsed, amd it is st~ested that surface or nsar surface ~ e m e n t s may not yield results that are coupled with deep tectonic stresses.
Classification and identification 79~77 DESCRIPTION (~ ROCK M A S ~ S FOR E N G I N ~ ! N G
PURPOSES. R E ~ BY THE GEOLOGICAL SOCIETY E ~ G I N ~ RING GROUP W(3RKING PARTY Q J Emg~g Geol, %'10, N~, 1977, PS55-B88 su~marises previous w~rk on rock mass classification and rock mass parameters. The requirements of a scheme of description are defined, and rock material description and rock mass description considered in detail. Techniques for carrylr~ out classification t e s t s a r ~ for obtaining da~a are reviewed. The report fi~,11y smmarises l~ocedures for recordir~ and present i ~ descriptive data on rock masses.
7~o~
ONE POINT CONE P E ~ O M ~ LIQUID LIMIT TEST. TECHNICAL NOTE Clayton, C R I; Jukes, A W Geotechnlque, V28, N~, 1978, ~69-472 It is suggested that t h e cone penetrometer may reasonably be used in a one-point liquid limit test which will provide a cheap but relatively accurate alternative to the present British Sta~ one point Casagrar~e method. Likely errors associated with this method are ~ y s e d statistically.
Geology 79~o79 ZW~a~T~Om~L C O L L O ~
timg to variability in emglmeerim~ behavlour are also Identified. Extem~ed classifications based on t h i s w ~ k a r e ~ t ~ e s t e d t o a i d i n prediction of %he e~ginee~Ing properties of t ~ l l s and in s e l e c t i o n of samplir~ and testing techniques.
Earthquake mechanisms and effects EARTHQUAKE MOTIONS 792082 SITE ~ E I q T Romsta~ K M; Bruce, J; HL-~chinson, J R J Geotech E ~ Div ASCE, VI04, NSK~!I, Nov
z978,
P',..389-z~oo
A statistical method for modeling time varying esrthquake imduced acceleration levels which will produce smooth response spectrums o f t h e desired shape add amplitude levels is developed. Specific records are derived to simolate a mean s p e c t r ~ developed from historically recorded rock motions and also for AEC Regulatory Guide s p e c i f i c . The s y r ~ h e t i c r o c k motion is then used as the i:E.f~ mo~ion tO a mJmber of site corditions simulatir6 stiff~ deep cohesionless and soft to medium clay ~r~ sand sites usir~ the co~m~er program SHAKE. The results are compared to mean spectra for similar sites derived from historically recorded motions and shown to provide reasonable eDginee~img estimates of site motions. Auth.
Frost action, permafrost and frozen ground 792083 SEISMIC HESPONSE OF FROZEN GROUND Finn, W D L; Yomg, R N J Geotech E ~ Div ASCE, V104, NGTIO, Oct 1978, P1225-].241
ON COAt FLZ~T CLAYS
IN OSTRAU (IN G~i4/V) Berger, K Gluckauf, VII3, N23, i Dec 1977, Pi135-i137 S.~-~ises papers from a colloquit~ held in Ostrau. Czechoslovakia on on 31 May to 3 June 1977. Topics covered include the occurrence of flint clays in coal-bearir~ strata throu~out Western ard Eastern Europe, t h e composition of various exan~les, add their use particularl~ in stratigraphy for identifying add defining coalbeariDg layers. 792080 HYDROGEGLOGY AND E~INEERI~ GEOLOGY OF STI~'~IA
(z~ RUSSIA.) Matusev~ch, V M (~tor) Tr Tyumen Ini Inst, V~2, 197~, 2~8P
Environmental effects, weathering and soil formation 792081 GEN~IC I I ~ E S ON THE PROFE~IES OF TILLS M c G ~ , A; Derbyshire, E Q J Emgng Geol, VlO, ~ , 1977, PB89-~IO Presents a means of identifying the various geological types of till using a classification b as ed on modes of formation, translxE~atlon~ ard deposition. The fabric features contribu-
Field data on the behaviour of frozen ground during the Alaska earthquake of 196~ are reviewed. It is shown that fully f r o z e n g r o u ~ behaves well durir~ earthquakes ar~ that moat eDgineering problems are encountered in frozen groumd when saturated cohesionless soils are trapped beneath the frozen surface layer. A procedure for t h e d ~ c effective s t r e s s response amslysis of t h i s case is presented. Existing data on stress-strain properties of frozen ground a r e reviewed critically. Use of s e i ~nic r e f r a c t i o n t e c h n i q u e s in f r o z e n groumd, both onshore ~,~d offshore, are 'considered. Freezing pherEmema essential for underatamd1~g experimental data axzl field conditions a r e described. Auth.
792084 L I Q ~ A C T I O N OF THAWED LAYERS IN FR(ZZEN SOIL Flmm, W D L; Yomg, R N; Lee, K W J Gec~ech E~g:~ DIv ASCE, VI04, ~ i 0 , 1978, P12~3-1255
Oct
A dy~--~c effective stress method is iEesel~ed for assessimg ~he liquefaction ix~en~ial of thswed layers of saturated cohesionless soils s e a l e d between f r o z e n s u r f a c e l ~ e r s a~d Ivermafrost. Anslysis ir~icstes that the liquefaction p o t e n t i a l i s i ~ r e a e e d by t h e p r e s e n c e o f a f r o z e n s u r f a c e l a y e r . The Ix~re-wate~" ;~ejsures c r e a t e d by d y ~ - ~ c s t r e s s gradients e r e r e d i s t r i b u t e d upwards t o regions of lower effective s t r e s s , a~d t h e ~ cannot d i s s i p a t e because d r a i n a g e i s " s e a l e d o f f , t h u s leadiDg t o i r a t e -