MODELING FAILURE OF COHESIVE SLOPES

A STUDY TO IMPROVE AND FURTHER DEVELOP TECHNIQUES FOR MODELING HOMOGENOUS COHESIVE SOIL STABILITY PROBLEMS IS REPORTED. THE PROBLEM OF SIMPLE SLOPES WAS CHOSEN BECAUSE A NUMBER OF ANALYTICAL METHODS EXISTED FOR COMPARISON. IF THE TECHNIQUES DEVELOPED PRODUCED ACCURATE RESULTS, THEN IT WAS CONCLUDED THAT THE SAME METHODS MAY BE EXTENDED TO A VARIETY OF PRACTICAL PROBLEMS. THE FAILURE OF HOMOGENEOUS COHESIVE SLOPES CAN BE MODELED USING CLEAN QUARTZ SAND IN THE LABORATORY. EFFECTIVE COHESION CAN BE CONTROLLED IN SAND MODELS THROUGH ALL AROUND VACUUM CONFINEMENT. FIVE RECOMMENDATIONS MADE ARE: (1) USE THE LOOSEST POSSIBLE DENSITY TO ELIMINATE QUESTIONS ARISING FROM A DIFFERENCE IN PEAK AND RESIDUAL STRENGTHS. (2) CAREFULLY DETERMINE THE PLANE STRAIN FRICTION ANGLE OF THE MODELING MATERIAL. TESTS OF LONG SHALLOW SLOPES CAN BE USED FOR THIS PURPOSE LACKING SPECIALIZED PLANE STRAIN EQUIPMENT. (3) SIMPLE SLOPE MODELS SHOULD BE AT LEAST 1 FOOT HIGH. (4) WIDTH TO HEIGHT RATIOS EXCEEDING 3 ARE RECOMMENDED USING A POLYSHEET MEMBRANE FOR CONFINEMENT. (5) MEASUREMENTS ARE CONVENIENTLY TAKEN FROM A CENTRAL SECTION WHICH CAN BE PERMANENTLY PRESERVED FOLLOWING FAILURE WITH CHEMICAL GROUT. THE RESULTS OF THE MODEL TESTS GENERALLY CONFIRM EXISTING METHODS OF SLOPE STABILITY ANALYSIS. BOTH THE SLOPE OF FAILURE SURFACE AND CALCULATED FACTORS OF SAFETY FROM THE LOG-SPIRAL ANALYSIS WERE IN AGREEMENT WITH THE LABORATORY TEST RESULTS. THE MODEL TESTS WERE LIMITED TO A FRICTION ANGLE OF 33 DEGREES. FRICTION ANGLES AS LOW AS 15 DEGREES HAVE BEEN OBTAINED BY MIXING LEAD SHOT AND GLASS BALLS WITH TEFLON POWDERS AND SPRAYS. THE MODELING TECHNIQUES REPORTED ARE CONSIDERED APPLICABLE TO A VARIETY OF STABILITY PROBLEMS AND FURTHER RESEARCH ON THE PULLOUT CAPACITY OF BURIED ANCHORS IS CURRENTLY UNDERWAY.

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 263-86

Subject/Index Terms

Filing Info

  • Accession Number: 00236446
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Nov 3 1973 12:00AM