Triaxial Creep Test Study On Saturated Clay Soil Of Several Consolidation Degree Under Non-drainage Condition

In this dissertation, the writer analyzed the changing property of pore water pressure, volume of sample as time elapsing and its influence on creep property through improving the experiment technics and method, deep research about the creep behaviour of clay soil.I changed the preparing approach of soil sample and used test stand develpoed by myself to fix mould and guide bar in oeder not to avoid the fluctuation of mould and the tilt of guide bar. In order to eliminate the air in the connected system composed by latex film,permeable stones,pressure head and pipeline, I first carryied on vacuumizing in the connected system inside latex film through pipeline after I had airproofed the triaxial cell with installing soil sample internal. Then let the water reflow and full the system. Finally I poured water into the triaxial cell through the pipeline of confining pressure and carried on the triaxial loading.With the aim to overcome the limitation that we cann't record several data in the same time by hand, I set up a video recording system. I adopted the monitoring system of WeiHang monitoring system to record the axial deformations,confining pressure,pore water pressure and volume change of water inside the cell in creep process at any time. This system can not only record various kinds of physical quantities, but also realize the far-monitoring for the experiment process through computer or mobile phone.This paper had come to a conclusion about the soil sample relationship curve of the strain and time under respective consolidation degree through the triaxial creep test for the soil sample under four different consolidation degree. It also had analyzed rule about the pore water pressure changing of the soil sample in the creep experiment process of under-consolidated soil. The approaches of effective stress in creep experiment had been drawn in p'-q'coordinate system.This paper also had concluded the relationship between the time and water discharge of consolidation drainage through the triaxial creep experiment for normally consolidated soil under different surrounding stress. In the experiment it also had analyzed the influence on soil sample volume because of the stress level and finally concluded the relationship curve about the stain and time of solid, pore water pressure -time and volume change -time of the soil sample under different surrounding stress.