软土地区电缆沟通道基坑开挖回弹控制研究  

Excavation Bottom Rebound Deformation Control of a Utility Culvert Excavation in Soft Soils

作　　者：钮佳伟 郭锐 谭文韬 陆超 陈孔阳 周震海 NIU Jiawei;GUO Rui;TAN Wentao;LU Chao;CHEN Kongyang;ZHOU Zhenhai(Suzhou Electric Power Design Institute Co.Ltd,Suzhou 215000)

机构地区：[1]苏州电力设计研究院有限公司,江苏苏州215000

出　　处：《土工基础》2022年第6期894-898,共5页Soil Engineering and Foundation

基　　金：国家自然科学基金项目(51578145)。

摘　　要：开挖电缆沟通道形成的基坑具有宽度小且狭长的特点,在软土地区易产生过大的回弹变形进而影响工程质量,需对坑底进行加固。考虑到坑底采用旋喷桩加固,采用ABAQUS软件建模研究加固深度、置换率、地基土性质以及支护桩嵌固深度对坑底回弹变形的影响规律。结果表明,提高加固深度和加固区的置换率是降低坑底回弹量的有效措施,但当加固深度达到一定值时,继续增加加固深度效果不明显。对于电缆沟通道工程,加固深度在4 m~8 m较为合理。支护结构的嵌固深度越深,地基土的强度指标越高,坑底回弹量越小,但加固深度越深,两者对坑底回弹量的影响越小。The foundation excavation area for the cable utility culvert has the characteristics of long and narrow, which is easy to induce excessive rebound deformation at the bottom of the excavation in soft soils and further adversely affect the project construction quality. Therefore, it was necessary to improv the bottom of the excavation by using high pressure jet grout method. The commercial ABAQUS software was used to study the influence of improvement depth, replacement ratio, properties of foundation soil and embedded depth of supporting soldier pile structure on rebound deformation at the excavation bottom. The results show that increasing the depth of improvement and the replacement ratio of the improvement area are effective measures to reduce the rebound deformation at the bottom of the excavation. However, when the improvement reaches a critical depth, the rebound reduction effect becomes not obvious, even if continue to increase the improvement depth. The improvement depth is more suitable between 4m and 8m for the cable utility culvert project. The deeper the embedded depth of the supporting soldier pile structure or the higher the strength parameter of the foundation soil, the smaller the rebound deformation of the bottom of the excavation. However, with the increase of improvement depth, both factors have less influence on the bottom rebound deformation.

关 键 词：电缆沟通道 基坑回弹 土体加固 数值模拟 

分 类 号：TU473[建筑科学—结构工程]