摘要
为了研究界面粗糙度、温度变化和超固结比(over consolidation ratio,OCR)对桩-土界面剪切强度、孔压响应和体积变形影响,采用应变式直剪仪对直剪盒加以改造,分别对光滑和粗糙两种混凝土-饱和黏土界面进行非等温固结不排水剪切试验.结果表明,当OCR≤3时,随着OCR值减小,从室温升温或者降温和提高界面粗糙度均能提高界面剪切强度,孔隙水压力为正值,升温或者降温时的孔压均低于室温情况;当OCR=6时,孔隙水压力为负值,在剪切过程中发生剪胀,升温或者降温反而会略微降低界面的剪切强度.当OCR≤3时,增大界面粗糙度或升高温度,都会削弱土体的软化现象,而降温会强化土体的软化现象;当OCR=6时,界面剪切性质基本不变.说明界面粗糙度和温度变化对界面剪切特性的影响只在OCR值较小时比较显著,当OCR值足够大时,影响基本可以忽略.
In order to study the effects of interface roughness,temperature change and over consolidation ratio(OCR)on pile-soil interface shear strength,pore pressure response and volume change,the direct shear box was modified by strain direct shear instrument,and non isothermal consolidated undrained shear tests were carried out on smooth and rough concrete saturated clay interfaces respectively. The results show that when OCR ≤ 3,decreasing OCR value,heating or cooling and increasing interface roughness can improve interface shear strength,pore water pressure is positive,and the pore pressure after heating or cooling is lower than that at room temperature.When OCR = 6,the pore water pressure is negative,and dilatancy occurs in the shear process. On the contrary,heating or cooling will slightly reduce the shear strength of the interface. When OCR ≤ 3,increasing the interface roughness and temperature will weaken the softening phenomenon of soil,and cooling will strengthen the softening phenomenon of soil. When OCR = 6,the interfacial shear properties are basically unchanged. It means that the influence of interface roughness and temperature change on interface shear characteristics is significant only when the OCR value is small,and the influence can be basically ignored when the OCR value is large enough.
作者
王晓强
张志超
王烁堯
WANG Xiaoqiang;ZHANG Zhichao;WANG Shuoyao(School of Civil Engineering,Chongqing University,Chongqing 400045,P.R.China;Key Laboratory of New Technology for Construction of Cities in Mountain Area of Ministry of Education,Chongqing University,Chongqing 400045,P.R.China)
出处
《深圳大学学报(理工版)》
CAS
CSCD
北大核心
2022年第1期13-19,共7页
Journal of Shenzhen University(Science and Engineering)
基金
国家自然科学基金资助项目(51978104)
中央高校基本科研业务费专项资金资助项目(2020CDJQY-A068)。
关键词
岩土工程
能量桩
饱和黏土
固结不排水
剪切特性
粗糙度
温度效应
超固结比
geotechnical engineering
energy pile
saturated clay
consolidated undrained
shear behavior
rough-ness
temperature effect
over consolidation ratio(OCR)