摘要
在地震、波浪等动力荷载作用下钙质砂地基易发生砂土液化造成结构破坏,微生物诱导碳酸钙沉淀技术(MICP)可以大规模处理钙质砂地基,提高其抗液化能力。本文采用循环三轴试验研究微生物加固钙质砂的动孔压发展特性,探讨有效围压、动应力比、相对密实度以及加固程度对微生物加固钙质砂动孔压发展的影响。研究表明,微生物加固钙质砂的孔压发展模式受动应力比和微生物加固程度的影响较大,根据动应力比和加固程度不同,微生物加固钙质砂表现出3种不同的孔压发展模式,孔压曲线随动应力比和加固程度增加逐渐由S型向双曲线型过渡。根据动孔压的发展规律,提出一种适用于微生物加固钙质砂的统一孔压应力模型,通过对比验证了该模型在预测微生物加固钙质砂动孔压发展上的适用性。
The calcareous sand foundation may be liquefied to cause structural damages under dynamic loadings such as earthquakes and waves. The microbially induced calcite precipitation(MICP) can enhance the strength of the calcareous sand foundation on a large scale and improve its liquefaction resistance. In this paper,the dynamic pore pressure development of MICP-treated calcareous sand was studied through a series of cyclic triaxial tests,and the effects of the effective confining pressure,the dynamic stress ratio,the relative density and the biocementation level on the development of the dynamic pore water pressure of MICP-treated calcareous sand were investigated. It is found that the pore water pressure development of MICP-treated calcareous sand is greatly affected by the dynamic stress ratio and the biocementation level. Based on the dynamic stress ratio and the biocementation level,MICP-treated calcareous sand presents three different pore water pressure development patterns. The pore water pressure curve gradually transitions from S-type to hyperbolic type with increasing the dynamic stress ratio or the biocementation level. Based on the development of the dynamic pore water pressure,an uniform pore water pressure model was proposed for MICP-treated calcareous sand. The advantage of this model over other models in predicting the development of the dynamic pore water pressure in MICP-treated calcareous sand was demonstrated through comparisons.
作者
刘汉龙
张宇
郭伟
肖鹏
黄明
楚剑
肖杨
LIU Hanlong;ZHANG Yu;GUO Wei;XIAO Peng;HUANG Ming;CHU Jian;XIAO Yang(School of Civil Engineering,Chongqing University,Chongqing 400045,China;Key Laboratory of New Technology for Construction of Cities in Mountain Area,Chongqing University,Chongqing 400045,China;School of Civil Engineering,Tianjin University,Tianjin 300072,China;Chongqing Railway Investment Group Co.,Ltd.,Chongqing 400023,China;College of Civil Engineering,Fuzhou University,Fuzhou,Fujian 350116,China;School of Civil and Environmental Engineering,Nanyang Technological University,Singapore 639798,Singapore)
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2021年第4期790-801,共12页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金资助项目(41831282,51922024,52078085)。
关键词
土力学
钙质砂
循环三轴试验
动孔压模型
MICP
微生物温控加固技术
soil mechanics
calcareous sand
cyclic triaxial test
dynamic pore water pressure model
microbially induced calcite precipitation(MICP)
temperature-controlled MICP treatment technology
