摘要
通过考虑不同水泥掺量、不同围压等试验条件下的固结不排水三轴试验,研究了盾构始发和接收端粘性加固土和砂性加固土力学性质,并根据试验结果对两者加固土承载机制进行了分析,研究结果表明:(1)无论原状土土性如何,水化物的存在使得加固土的应力-应变曲线由原状土的硬化型向软化型转变,且曲线阶段性明显;(2)加固土偏应力峰值由摩擦分量和粘结分量组成,当A_w>5%时,以粘结分量为主,反之则以摩擦分量为主;(3)粘性加固土和砂性加固土两者虽原状土土性不同,但水化物粘结的存在,使得两者的力学性质和承载机制基本类似,但两者应力应变曲线的软化程度不同。
According to the results of triaxial undrained compression test under different test conditions( including original soil,cement content and confining pressure),the mechanical behaviors and bearing mechanism of cohesive and sandy reinforced soil at shield originating and receiving end are analyzed. Results show:( 1) Compared to the stress-strain relationship of uncommented soil which belongs to hardening type,that of the cemented soil becomes softening because of hydrate. Meanwhile,the curve of stress-strain shows an obvious periodic characteristic.( 2) The peak of deviator stress has two components,friction and cementation. If the cement content Awis more than5%,the cementation component occupies a relatively greater proportion,otherwise the friction is the mainly part.( 3)Though undisturbed soil properties of cohesive and sandy reinforced soil are different,their mechanical behaviors and bearing mechanism turn to be similar due to hydrate except their softening are different.
出处
《地下空间与工程学报》
CSCD
北大核心
2016年第S2期538-544,共7页
Chinese Journal of Underground Space and Engineering
基金
珠海大横琴股份有限公司和上海隧道工程有限公司资助项目(2015-sk-4)
国家自然科学资金(41372276)
关键词
盾构始发与接收
三轴试验
加固土
承载机制
shield originating and receiving
triaxial test
reinforced soil
bearing mechanism