固化黄土力学特性三轴试验研究

Triaxial tests on mechanical properties of solidified loess

为进一步认识固化黄土的力学特性,以郑州地区黄土为试验材料,制备不同固化剂掺量的试样,并在标准养护条件下养护至试验龄期后饱和。应用GDSTTS标准应力路径三轴仪,开展固结不排水(CU)剪切试验,主要研究围压、固化剂掺量以及养护龄期对固化黄土力学特性的影响。试验结果表明:郑州地区固化黄土具有显著的结构性,其应力应变曲线呈现出应变软化特征,并可用驼峰型三参数表达式描述;同时,增大围压和固化剂掺量以及延长养护龄期,固化黄土的峰值应力及残余应力都增大、养护龄期超过一定时间后,其对固化黄土强度的影响趋弱。

To further investigate the mechanical properties of solidified loess,specimens with different solidified agent content were prepared with loess in Zhengzhou area,and cured to the test age under standard curing conditions before they were saturated.Using GDSTTS standard stress path triaxial apparatus,a series of consolidated-undrained(CU)shear tests were carried out,and the influences of confining pressure,solidified agent content,and curing age on the mechanical properties of solidified loess were studied.The experimental results show that the solidified loess in Zhengzhou area has remarkable structural characteristics;the stress-strain curves are characterized by strain softening and can be described by three-parameter expression of hump type.In addition,the peak stress and residual stress of solidified loess increase with the increase in the confining pressure,the content of curing agent,and the curing age.However,the influence of the curing age on the strength of solidified loess weakens after curing for more than a certain time.