Tertiary Creep Reproduction by Back-Pressure-Controlled Test in DPRI-7

摘要

Fukuzono (Proceedings of 4th international conference and field workshop on landslides, Japan, pp 145–150, 1985) developed amethod for predicting final failure time of a slope based on the findings derived from large scale flume test series that log of acceleration is proportional to log of velocity of surface displacement suddenly before failure. He proposed a simple method for predicting the failure time by plotting the inverse velocity of surface displacement (1/v). Yet, its mechanism is still unknown. To investigate the tertiary creep mechanism in soils, a series of back-pressure-controlled test on saturated sandswere undertaken in ring shear apparatus. The tests were conducted under particular normal stress and shear stress with porewater pressure changes to simulate the potential sliding surface condition in heavy rainfall. Sand and its mixture with clay material were used for specimen. Consequently, these tests could reproduce tertiary creep to failure, in which similar log v-log a relationship and a value range was found. While, linear relationship of a and A values was found.