饱和环境下珊瑚礁灰岩-混凝土界面剪切特性试验研究  

Experimental Study on the Shear Characteristics of Coral Reef Limestone⁃concrete Interface Under Saturated Environment

作　　者：姚翔川 刘文 罗会武[3] 陈培帅[3] YAO Xiangchuan;LIU Wen;LUO Huiwu;CHEN Peishuai(CCCCSHEC(Chengdu)Construction Engineering Co.,Ltd.,Chengdu,Sichuan 610218,China;CCCC Wuhan Zhixing International Engineering Consulting Co.,Ltd.,Wuhan,Hubei 430040,China;CCCC Second Harbor Engineering Co.,Ltd.,Wuhan,Hubei 430040,China)

机构地区：[1]中交二航局(成都)建设工程有限公司,四川成都610218 [2]中交武汉智行国际工程咨询有限公司,湖北武汉430040 [3]中交第二航务工程局有限公司,湖北武汉430040

出　　处：《施工技术(中英文)》2025年第3期143-150,共8页Construction Technology

基　　金：国家重点基础研究发展计划。

摘　　要：在珊瑚礁灰岩地层进行桩体施工时,由于其多孔特性及脆性材料特点会形成锯齿形状桩身侧壁,结合钻孔灌注桩土间存在的无填充、泥皮填充、浇筑及后浇筑界面填充形式,对珊瑚礁灰岩地层桩体承载特性进行研究。针对超声波扫孔数据开展珊瑚礁灰岩-混凝土界面剪切特性试验,并建立数值模型进行模拟分析。研究结果表明,当界面无填充和泥皮填充时,锯齿形状对界面咬合力和摩擦角均有较大影响,泥皮填充对界面主要起润滑作用,泥皮填充后界面咬合力和摩擦角均有一定程度的减小。当界面填充形式为浇筑和后浇筑时,界面抗剪强度主要由胶结力提供,锯齿形状对抗剪强度的影响不明显。无填充及泥皮填充界面剪切破坏形式主要表现为界面滑移,浇筑和后浇筑填充界面剪切破坏形式主要表现为界面破坏及珊瑚礁灰岩破坏,界面形状对破坏形式具有较大影响。界面轴向刚度、剪切刚度、黏聚力和摩擦角对界面抗剪强度与剪切应力增长形式均有较大影响,其中界面刚度主要影响剪切应力增长形式,黏聚力和摩擦角对剪切应力峰值有较大影响。锯齿桩在形成泥皮层或未胶结区域通过锯齿咬合力弥补了因泥皮及未胶结部分产生的桩侧摩阻力降低,从而提高了桩体承载力,桩身越长该效果越明显。采用后压浆方式可有效提高钻孔灌注桩承载力,桩端以下3m范围内含有大量压浆料颗粒,桩端以下1m范围内出现了压浆料结石体,实现了压力浆液填充珊瑚礁灰岩孔隙,改善了珊瑚礁灰岩层中薄弱区域的受力性能。When pile body construction is carried out in coral reef limestone stratum,due to its porous characteristics and brittle material characteristics,it will form a sawtooth shape pile body sidewall,combined with the existence of unfilled,mud⁃cake filled,poured and post⁃poured interfacial fill between the bored cast⁃in⁃place piles and soil,to study the bearing characteristics of the coral reef limestone stratum pile body.For the ultrasonic sweep hole data to carry out the coral reef limestone⁃concrete interface shear characteristic tests,and establish a numerical model for simulation analysis.The research results show that when the interface is unfilled and mud⁃cake filled,the sawtooth shape has a greater effect on the interface bite force and friction angle,and the mud⁃cake filled mainly plays a lubricating role on the interface,and the interface bite force and friction angle are reduced to a certain extent after the mud⁃cake filled.When the interface filling form is poured and post⁃poured,the interface shear strength is mainly provided by the cementation force,and the effect of the sawtooth shape on the shear strength is not obvious.The shear damage form of unfilled and mud⁃cake filled interface is mainly manifested as interface slip,and the shear damage form of poured and post⁃poured filled interface is mainly manifested as interface damage and coral reef limestone damage,and the interface shape has a greater influence on the damage form.Interface axial stiffness,shear stiffness,cohesion and friction angle have a greater effect on the interface shear strength and shear stress growth form,of which the interface stiffness mainly affects the shear stress growth form,and cohesion and friction angle have a greater effect on the peak shear stress.Sawtooth pile in the formation of mud⁃cake stratum or uncemented area through the sawtooth bite force,to make up for part of the mud⁃cake and uncemented part of the pile side of the friction force generated by the reduction,so as to improve the pile bo

关 键 词：桩基础 珊瑚礁灰岩 混凝土 力学性能 试验 

分 类 号：TU528[建筑科学—建筑技术科学]