循环荷载作用下粉质黏土-混凝土界面强度预测研究  

Prediction of strength of silty clay-concrete interface under cyclic loading

作　　者：杨俊超 夏元友[2] 崔飞龙 李丽华[4] 吴炯晖 陈晨 田亮 YANG Junchao;XIA Yuanyou;CUI Feilong;LI Lihua;WU Jionghui;CHEN Chen;TIAN Liang(Guangzhou First Municipal Engineering Co.,Ltd.,Guangzhou 510250,China;Wuhan University of Technology,Wuhan 430070,China;Zhengzhou University of Technology,Zhengzhou 450044,China;Hubei University of Technology,Wuhan 430070,China;Wuhan Institute of Technology,Wuhan 430073,China;China Railway Construction Group Corporation Limited,Beijing 100040,China)

机构地区：[1]广州市第一市政工程有限公司,广东广州510250 [2]武汉理工大学,湖北武汉430070 [3]郑州工程技术学院,河南郑州450044 [4]湖北工业大学,湖北武汉430068 [5]武汉工程大学,湖北武汉430073 [6]中铁建设集团有限公司,北京100040

出　　处：《岩土工程学报》2024年第S02期194-199,共6页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金面上项目(52278369);中铁建设集团有限公司科技研究开发计划项目(23-46c);广州市建筑集团有限公司科技计划项目(2024-KJ080)。

摘　　要：基于3D扫描和打印技术,制作了与混凝土灌注桩相同的界面混凝土试件,并进行了一系列粉质黏土-混凝土界面循环剪切试验。通过粉质黏土-混凝土界面循环剪切试验,揭示不同循环周期、循环幅值条件下界面强度的衰减规律。通过对循环幅值和法向压力幂函数拟合,对循环稳定后-土界面强度衰减系数进行表征,并结合黏土-混凝土界面峰值强度模型,提出粉质黏土-混凝土界面强度衰减模型。结果表明:在15次循环后,部分循环的剪切位移-剪切应力曲线近似重合;当循环幅值逐渐增大,剪切阶段与卸载阶段应力-应变曲线均呈现线性趋势,每个循环圈内加载与卸载的斜率基本保持一致,类似“平行四边形”;不同工况的循环稳定后界面剪切峰值强度折减系数D_(τ)存在相同的变化趋势,可通过循环幅值A和法向应力σ的无量纲非线性回归分析,提出循环稳定后黏土-混凝土界面剪切峰值强度折减系数D_(τ)表征方法,其拟合度较高。Based on the 3D scanning and printing technology,the concrete specimens with the same contact surface as the concrete cast-in-place piles are produced,and a series of silty clay-concrete interface cyclic shear tests are conducted.Through the cyclic shear tests on the silty clay-concrete interface,the attenuation laws of interface strength under different cyclic periods and cyclic amplitudes are revealed.By fitting the cyclic amplitude and normal pressure power function,the strength attenuation coefficient of the concrete-soil interface after cyclic stabilization is characterized,and by combining with the peak strength model for the clay-concrete interface,the strength attenuation model for the silty clay-concrete interface is proposed.The results show that the shear displacement-shear stress curves of some cycles coincide approximately after 15 cycles.When the cyclic amplitude increases gradually,the stress-strain curves at the shear stage and unloading stage show a linear trend,and the slopes of loading and unloading in each cycle are basically consistent,similar to"parallelogram".The reduction coefficient D_(t)of the peak interfacial shear strength after cyclic stabilization has the same variation trend under different working conditions.A dimensionless nonlinear regression analysis of cyclic amplitude A and normal stressscan be used to obtain the reduction coefficient D_(t)of the peak interfacial shear strength after cyclic stabilization,which has a high degree of fitting.

关 键 词：界面剪切 界面强度 粗糙度 残余强度 峰值强度预测 

分 类 号：TU44[建筑科学—岩土工程]