黏土中考虑中主应力和卸荷效应的压密注浆模型研究  

Post Grouting Compaction Model Considering Intermediate Principal Stress and Unloading Effect in Clay

作　　者：龚昕[1,2,3] 赵程 吴悦[4] GONG Xin;ZHAO Cheng;WU Yue(Key Laboratory of Geotechnical and Underground Engineering,Ministry of Education,Tongji University,Shanghai 200092,China;Department of Geotechnical Engineering,Tongji University,Shanghai 200092,China;Institute of Civil Engineering,Jinggangshan University,Ji’an,Jiangxi 343009,China;Institute of Civil Engineering,Chongqing Jiaotong University,Chongqing 400074,China)

机构地区：[1]同济大学岩土及地下工程教育部重点实验室,上海200092 [2]同济大学地下建筑与工程系,上海200092 [3]井冈山大学建筑工程学院,江西吉安343009 [4]重庆交通大学土木工程学院,重庆400074

出　　处：《施工技术（中英文）》2022年第20期45-51,共7页Construction Technology

基　　金：国家自然科学基金(41672265,41272295)。

摘　　要：为研究中主应力对黏土考虑卸荷条件下压密注浆效应的影响,基于柱孔扩张理论和统一强度准则,建立考虑土体卸荷效应的压密注浆模型。分析在不同中主应力条件下,卸荷比为0,0.8时的压密注浆极限注浆压力、径向应力、环向应力和径向位移沿径向的分布关系。研究结果表明:在同一卸荷比下,压密注浆极限注浆压力随着中主应力系数的增大而呈非线性增加并逐渐趋于稳定的趋势;在同一中主应力条件下,卸荷比为0.8时的压密注浆极限注浆压力小于卸荷比为0时的情况;在同一注浆压力下,中主应力系数b对径向应力、环向应力和径向位移沿径向分布规律不产生影响,但对于稳定径向应力、稳定环向应力、稳定径向位移和最小环向应力在孔周出现位置产生影响,即对应的径向距离均随着中主应力系数b的减小而增大,并且随着土体内卸荷程度的增大,该影响规律越显著。In order to study the influence of the intermediate principal stress on the compaction grouting effect of the clay considering the unloading condition, a compaction grouting model considering the unloading effect of soil was established based on the cylindrical cavity expansion theory and unified strength criterion. The ultimate grouting pressure, the distributions of radial stress, annular stress and radial displacement under different conditions of intermediate principal stress and unloading ratio of 0 and 0.8 are analyzed. The results show that under the same unloading ratio, the ultimate grouting pressure increases non-linear with the increase of intermediate principal stress coefficient and tends to be stable. At the same intermediate principal stress, the ultimate grouting pressure at the unloading ratio of 0.8 is less than that the unloading ratio of 0. At the same grouting pressure, the principal stress coefficient b has no effect on the distributions of the radial stress, the annular stress and the radial displacement, but the stable radial stress, the stable annular stress, the stable radial displacement and the minimum annular stress all increase with the decrease of the intermediate principal stress coefficient b, and with the increase of the degree of unloading in the soil, the influence law becomes more and more remarkable.

关 键 词：注浆 柱孔扩张 中主应力 模型 应力分布 

分 类 号：TU43[建筑科学—岩土工程]