- Email: [email protected]
Nonlinear soil models for irregular cyclic loadings
127A
796020 ENGINEERING PROPERTIES OF TEXAS LIGNITE AND ASSOCIATED ROCKS IN RELATION TO THE STABILITY OF AN INSITU GASIFICATION CHAM~ER Thompson, T W; Menezes, J J; Gray, K E In Situ, V1, N2, 1977, P171-190 796021 STUDY OF THE E~rECT OF C0~FINING PRESSURE ON ROCK S T R ~ T H SaluJa, S S; singh, D P; Kasivlswar~am, M J Mi~es Metals Fuels, V25, ~ , May 1977, P131-138
796022 STUDY ON ROCK FRACTURE CONDITZONIN THE CASE OF STRESS CONCENI'RATION DUE TO AN EI/~I~ICAL IN-
cLuslo~
(z~ J~PAmmE)
Tominaga, Y; Isobe, T J Min Metall Inst Japan, V93, NI078, Dec 1977,
Stress distributions are calculated using the complex stress function amd confcrmal representation for an infinite plate, under amy uniform edge force, containing an elliptical region filled with material having the modulus of elasticity and Poisson's ratio which are differe:It from those of the plate. The distributed stresses have almost the same values as the edge ones except the limited region of the tip of elliptical ir~uslon. 796023 ~ A R I ~
CAPACITY OF CYLINDRICAL ANCHORS IN
EFFECTS (IN GERMAN) Wernick, E I ~ i Inst Soil Rock Mech Univ Frid~icisma, Kerlsruhe, ~ , 1978, I~8P Cylimdrical soll ~"ehors and piles with small diameters embedded in non-cohesive soils reveal a pull-out resistance not expected on the basis of conventional analysis. An idealized model was developed reducing t h i s problem to a dilatimg sheer bared appearing near the anchor surface amd to a wedging effect in the adjacent soil body caused by this dilatancy, amd the model was tested experimentally. Conclusions ere drawn concerning stress-strain relations in the sheer band, amgles of intermal friction, amd the parameters controllimg skin friction. A modified direct shear apparatus has been designed, ard a method for calculating bearing capacity is presented.
796oz~ G m m ~ z ~ z ~ OF c o ~ sz~s zN ~ E UPPER s'n-~.sz~ C 0 ~ T 2 Z ~ (ZN ~OLZS~)
Prace Glownego Inst Oorn, Komunikst ~692 , 1978, 36P Gettabillty was described by an index f (according to the Protodyakonov shatter method), and an index U (compressive ~ r e ~ o f unshaped teat specimens). The percentage content of i ~ dividual petrogral~Lic varieties was determined, and the relation between f smd the instantaneous strength was determined for some varieties.
796025 CURABILITY OF COAL (IN POLISH) Sikora, W Prace Glownego Inst Gcrn, Komunlkat ~687, 1978, llP The process of cutting dull amd bright coals under various compressive stress comditions was studied in lab tests. The efficiency of ploughs depends much ~ r e on the natural minimg conditions than does that of sheerer-loaders. The effort r~cessary to cut coal in a stressed
condition depends partly on workability and c ~ r e s ~ I v e stremgth, but mainly on the petr~ graphic structure and elastic properties of the coal. 796026 C O N S T I T ~ RELATIONS OF COAL AND COAL MEASURE ROCKS Ko, H Y; Gerstle, K H USEM OFR 58-78, Sept 1977, 174P Repurts testing of rocks to obtain mechanical, i~dex, and geological properties which were analyzed anl correlated for strata zonation. Strength characteristics of all coal types tested in this ~ro~ect were analyzed t o ~ e r with additiomal information obtai~-d in other investigations. Trlaxial creep of coal was continued, with focus on boumdery drainage of T.he specimen ard on behavlour at high stress levels.
Deformation characteristics 796027 CCMFJTER MODEL FOR THE ANALYSIS OF GROUND MOVEMEETS IN LORDON CLAY Simpson, B; O'Ricrdan, N J; Croft, D D Geotechmique, V29, N2, Jlme 1979, P149-175 A computer model for the stress-strain behaviour of Lomdon Clay has been &eveloped for use in a non-linear finite element program. The behaviour of London Clay is divided into three ramges of strain: elastic, intermediate and plastic. It is shown that the model can be used to e~=~te %he results of b o t h ishoratcry and in altu tests. ~he movements around two excavations in London Clay, inmludlng the New Palace Yard Undergro~md Car Parks have also been competed retrospectively with considerable' success.
7960~ NONLIneAR SOIL ~ E L S LOADIRGS Pyke, R M J Geotech E ~
FOR IRREGULAR CYCLIC
Div ASCE, VI05, ~ ,
June
z979, PT15-726 Current R~lytieal a:~ mechanical models for sheer-stress shear-strain relationships trader cyclic l o a ~ ere described. ~nese models generally comply with Masing's suggestion that unloading and reloading curves have the same shape as the initial loading curve except that they ere enlarged by a factor of two. A new hypothesis is presented in which this scale factor is made a function of the stress level at the last reversal point. This new hypathesis leads %o shear-stress sheer-strain relationships umder irregular cyclic loading that appear to give better a~reeme~t with experimental data than the existing models. Auth.
796029 STRESS P~a-~ M E ~ :
SECOND EDITION Lambe, T W; Marr, W A J Geotech E~g~g Div ASCE, VI05, ~T6, June
1979, P727-738 This paper updates the stress path method l~roposed by the first author in 1967. The u/rlerlyiDg principle of the stress path method states that the behaviour of a soil element depends on the stress path for the history and for the stressing the element will receive in the future. This paper presents the stress
796020 ENGINEERING PROPERTIES OF TEXAS LIGNITE AND ASSOCIATED ROCKS IN RELATION TO THE STABILITY OF AN INSITU GASIFICATION CHAM~ER Thompson, T W; Menezes, J J; Gray, K E In Situ, V1, N2, 1977, P171-190 796021 STUDY OF THE E~rECT OF C0~FINING PRESSURE ON ROCK S T R ~ T H SaluJa, S S; singh, D P; Kasivlswar~am, M J Mi~es Metals Fuels, V25, ~ , May 1977, P131-138
796022 STUDY ON ROCK FRACTURE CONDITZONIN THE CASE OF STRESS CONCENI'RATION DUE TO AN EI/~I~ICAL IN-
cLuslo~
(z~ J~PAmmE)
Tominaga, Y; Isobe, T J Min Metall Inst Japan, V93, NI078, Dec 1977,
Stress distributions are calculated using the complex stress function amd confcrmal representation for an infinite plate, under amy uniform edge force, containing an elliptical region filled with material having the modulus of elasticity and Poisson's ratio which are differe:It from those of the plate. The distributed stresses have almost the same values as the edge ones except the limited region of the tip of elliptical ir~uslon. 796023 ~ A R I ~
CAPACITY OF CYLINDRICAL ANCHORS IN
EFFECTS (IN GERMAN) Wernick, E I ~ i Inst Soil Rock Mech Univ Frid~icisma, Kerlsruhe, ~ , 1978, I~8P Cylimdrical soll ~"ehors and piles with small diameters embedded in non-cohesive soils reveal a pull-out resistance not expected on the basis of conventional analysis. An idealized model was developed reducing t h i s problem to a dilatimg sheer bared appearing near the anchor surface amd to a wedging effect in the adjacent soil body caused by this dilatancy, amd the model was tested experimentally. Conclusions ere drawn concerning stress-strain relations in the sheer band, amgles of intermal friction, amd the parameters controllimg skin friction. A modified direct shear apparatus has been designed, ard a method for calculating bearing capacity is presented.
796oz~ G m m ~ z ~ z ~ OF c o ~ sz~s zN ~ E UPPER s'n-~.sz~ C 0 ~ T 2 Z ~ (ZN ~OLZS~)
Prace Glownego Inst Oorn, Komunikst ~692 , 1978, 36P Gettabillty was described by an index f (according to the Protodyakonov shatter method), and an index U (compressive ~ r e ~ o f unshaped teat specimens). The percentage content of i ~ dividual petrogral~Lic varieties was determined, and the relation between f smd the instantaneous strength was determined for some varieties.
796025 CURABILITY OF COAL (IN POLISH) Sikora, W Prace Glownego Inst Gcrn, Komunlkat ~687, 1978, llP The process of cutting dull amd bright coals under various compressive stress comditions was studied in lab tests. The efficiency of ploughs depends much ~ r e on the natural minimg conditions than does that of sheerer-loaders. The effort r~cessary to cut coal in a stressed
condition depends partly on workability and c ~ r e s ~ I v e stremgth, but mainly on the petr~ graphic structure and elastic properties of the coal. 796026 C O N S T I T ~ RELATIONS OF COAL AND COAL MEASURE ROCKS Ko, H Y; Gerstle, K H USEM OFR 58-78, Sept 1977, 174P Repurts testing of rocks to obtain mechanical, i~dex, and geological properties which were analyzed anl correlated for strata zonation. Strength characteristics of all coal types tested in this ~ro~ect were analyzed t o ~ e r with additiomal information obtai~-d in other investigations. Trlaxial creep of coal was continued, with focus on boumdery drainage of T.he specimen ard on behavlour at high stress levels.
Deformation characteristics 796027 CCMFJTER MODEL FOR THE ANALYSIS OF GROUND MOVEMEETS IN LORDON CLAY Simpson, B; O'Ricrdan, N J; Croft, D D Geotechmique, V29, N2, Jlme 1979, P149-175 A computer model for the stress-strain behaviour of Lomdon Clay has been &eveloped for use in a non-linear finite element program. The behaviour of London Clay is divided into three ramges of strain: elastic, intermediate and plastic. It is shown that the model can be used to e~=~te %he results of b o t h ishoratcry and in altu tests. ~he movements around two excavations in London Clay, inmludlng the New Palace Yard Undergro~md Car Parks have also been competed retrospectively with considerable' success.
7960~ NONLIneAR SOIL ~ E L S LOADIRGS Pyke, R M J Geotech E ~
FOR IRREGULAR CYCLIC
Div ASCE, VI05, ~ ,
June
z979, PT15-726 Current R~lytieal a:~ mechanical models for sheer-stress shear-strain relationships trader cyclic l o a ~ ere described. ~nese models generally comply with Masing's suggestion that unloading and reloading curves have the same shape as the initial loading curve except that they ere enlarged by a factor of two. A new hypothesis is presented in which this scale factor is made a function of the stress level at the last reversal point. This new hypathesis leads %o shear-stress sheer-strain relationships umder irregular cyclic loading that appear to give better a~reeme~t with experimental data than the existing models. Auth.
796029 STRESS P~a-~ M E ~ :
SECOND EDITION Lambe, T W; Marr, W A J Geotech E~g~g Div ASCE, VI05, ~T6, June
1979, P727-738 This paper updates the stress path method l~roposed by the first author in 1967. The u/rlerlyiDg principle of the stress path method states that the behaviour of a soil element depends on the stress path for the history and for the stressing the element will receive in the future. This paper presents the stress