不同有效应力恢复条件下的软土不排水抗剪强度试验研究  

Experimental study on undrained shear strength of soft soil under different effective stress recovery conditions

作　　者：赵居代[1] 安鹏程[1] 朱耀庭[2] ZHAO Ju-dai;AN Peng-cheng;ZHU Yao-ting(CCCC First Harbor Consultants Co.,Ltd.,Tianjin 300222,China;Tianjin Port Engineering institute Co.,Ltd.of CCCC First Harbor Engineering Co.,Ltd.,Tianjin 300222,China)

机构地区：[1]中交第一航务工程勘察设计院有限公司,天津300222 [2]中交天津港湾工程研究院有限公司,天津300222

出　　处：《中国港湾建设》2025年第3期62-69,共8页China Harbour Engineering

摘　　要：基于Bjerrum等提出的应力恢复方法以消除取样过程对土样的扰动,采用现场采取的软土原状样,分别进行了有效自重应力三轴K_(0)固结和平均有效应力三轴等压固结1 h和24 h不同时间的有效应力恢复,将应力恢复后不排水抗剪强度与室内十字板抗剪强度进行对比,并对其应力路径和应力应变关系等进行了比较分析,发现在应力恢复时间相同的条件下,软土不排水抗剪强度呈现出十字板最小(未固结恢复)、K_(0)固结次之、等压固结最大的特征,K_(0)固结1 h和固结24 h不排水抗剪强度较为接近,K_(0)固结1 h应力恢复效果明显,可为特殊情况下软土不排水抗剪强度的估算提供参考。Based on the Recompression method proposed by Bjerrum et al.to eliminate the disturbance of soil samples duringthe sampling process,the intact soft clay samples taken in the field were used to carry out the effective stress recovery of triaxialisobaric consolidation and K_(0)consolidation for 1 h and 24 h at different times under the conditions of effective overburdenpressure and average effective pressure,respectively.The undrained shear strength after effective stress recovery was comparedwith the strength of the laboratory VST,and the stress paths,stress-strain relationship were compared and analyzed,and it wasfound that under the same condition of stress recovery time,the undrained shear strength of soft clay showed the characteristicsof the minimum laboratory VST( unconsolidated recovery),followed by K_(0) consolidation shear,and the maximum isobaricconsolidation shear,and the undrained shear strength of K_(0)consolidation for 1 h and consolidation for 24 h was relatively close,and the stress recovery effect of K_(0)consolidation for 1 h is obvious,which can provide a reference for estimation of theundrained strength of soft soil under special circumstances.

关 键 词：软土 等压固结 K_(0)固结 应力恢复 十字板剪切 不排水抗剪强度 

分 类 号：U652.2[交通运输工程—港口、海岸及近海工程]