Effect of fine particle content on mechanical properties of frozen silty clay
The mechanical properties of seasonal permafrost have a significant impact on engineering,and the fines content in seasonal permafrost is an important parameter of its mechanical properties.To study the effect of fines content on the strength of seasonal frozen soil,the mechanical properties of frozen chalky clay at different fines contents(40%,45%,50%,60%,70%),different freezing temperatures(-5℃,-10℃,-15℃),and different surrounding pressures(50 kPa,80 kPa,120 kPa)were investigated by triaxial tests on frozen soil.The results show that the triaxial stress-strain curves of the specimens are all softening type.At the same fines con-tent,the peak strength of the soil samples gradually increased with the decrease of the negative freezing tempera-ture,where the increase was more drastic at-10～-5℃ than at-15～-10℃.With the increase of fines content,the distribution of soil brittleness index showed a parabolic shape,the cohesion of soil samples showed an in-creasing trend,while the internal friction angle of soil samples decreased.At the same time,the distribution of unfrozen water content at each fines content was obtained by thermometric method,and the calculation model of the change of permafrost cohesion with fines content at different negative temperatures was established,which can better predict the permafrost cohesion at any negative freezing temperature and any fines content.
frozen soil triaxialfine contentpeak intensitybrittleness indexunfrozen water content
万方数据
维普
