APPLICATIONS OF PLASTICITY IN SOIL MECHANICS

A PLANE STRAIN FORMULATION OF DRUCKER'S PERFECTLY PLASTIC THEORY FOR SOIL IS PRESENTED. UPPER AND LOWER-BOUND SOLUTIONS TO PROBLEMS INVOLVING THE STABILITY OF SLOPES AND FOUNDATIONS AND THE PRESSURES AGAINST RETAINING STRUCTURES ARE OBTAINED. THE LOWER-BOUND SOLUTIONS ARE OBTAINED FROM ARBITRARY EQUILIBRIUM STATES, THE UPPER-BOUND SOLUTIONS FROM KINEMATIC ANALYSES USING THE PLASTIC STRESS-STRAIN RELATIONS AFTER YIELD. THE RESULTS INDICATE THAT SOLUTIONS BASED ON CONVENTIONAL SLIPSURFACE ANALYSIS MAY BE UNSAFE. THE UPPER AND LOWER-BOUND SOLUTIONS ARE USEFUL GUIDES IN MAKING DESIGN DECISIONS. /ASCE/