基于CEL方法的混凝土板桩静压贯入减阻方法研究  

Research on the Static Penetration Resistance Reduction Method of Concrete Sheet Pile Based on CEL

作　　者：侯英伟 王建[1] 曹东 HOU Ying-wei;WANG Jian;CAO Dong(College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing 210098,China;Datang Environment Industry Group Co., Ltd., Beijing 100097,China)

机构地区：[1]河海大学水利水电学院,南京210098 [2]大唐环境产业集团股份有限公司,北京100097

出　　处：《中国农村水利水电》2020年第6期154-159,共6页China Rural Water and Hydropower

基　　金：国家自然科学基金项目(51779084);江苏省研究生科研与实践创新计划项目(SJKY19_0497);中央高校基本科研业务费专项资金资助(2019B70214)。

摘　　要：基于ABAQUS中的CEL方法(耦合的欧拉-拉格朗日方法)对混凝土板桩结构的静压贯入过程进行了三维数值模拟,对板桩贯入过程中土体的破坏模式、阻力的发展规律等问题进行了研究,并从桩底预设刃脚、土体钻孔卸压两方面进行了减阻效果定量分析。研究结果表明,平底板桩和带刃脚板桩在贯入过程中土体破坏模式存在较大差别,前者在贯入过程中出现明显的塑性贯通区,后者以刺穿破坏为主,未见连通地面的塑性贯通区;无减阻措施下,平底板桩总贯入阻力可达2.3 MN,对于板桩结构而言,贯入后期侧摩阻力占据绝对的比重;预设刃脚的减阻效果有限,60度刃脚、50度刃脚、40度刃脚情况下,总贯入阻力分别减少13.04%、17.39%、26.09%;土体钻孔卸压的减阻效果明显优于预设刃脚的减阻效果,其中钻孔开挖比例31.4%、47.1%、62.8%、78.5%(对应于钻2孔、3孔、4孔、5孔)情况下总阻力分别减少26.09%、34.78%、43.48%、56.52%,考虑到工程量以及某些后期需要利用摩擦力的工程,推荐采用钻孔开挖比例47.1%、62.8%;采取减阻措施后在贯入初期减阻效果明显,随着贯入深度的增加,减阻效果大致呈现先下降后上升,随后稳定的规律。The 3d numerical simulation of static penetration process of concrete sheet pile structure is carried out based on the CEL method(coupled Euler-Lagrange)in ABAQUS,the failure mode and the development law of resistance in the process of sheet pile penetration are studied,and quantitative analysis of resistance reduction effect is made from two aspects:presetting edge foot of pile bottom and soil drilling.The results show that there is a great difference between the soil failure modes of flat bottom pile and sheet pile with edge in the penetration process,the former obvious plastic penetration zone during penetration,the latter is mainly impingement failure,but there is no plastic through zone connecting the ground.The total penetration resistance can reach 2.3MN without resistance reduction measures,and for sheet pile structure,pile side friction resistance occupies an absolute proportion at the later penetration stage.The reduction effect of preset edge foot is limited,under the circumstances of 60 degree edge foot,50 degree edge foot and 40 degree edge foot,the total penetration resistance decreases by 13.04%,17.39%and 26.09%respectively.The resistance reduction effect of soil drilling is obviously better than that of preset edge foot,in which the total resistance decreases by 26.09%,34.78%,43.48%and 56.52%respectively when drilling ratios are 31.4%,47.1%,62.8%and 78.5%(corresponding to drilling 2,3,4 and 5 holes).Considering the amount of work and some projects requiring the use of friction,47.1%and 62.8%drilling ratios are recommended.At the initial stage of penetration,the resistance reduction effect is obvious.With the increase in penetration depth,the drag reduction effect generally presents a law of first decline,then rise,and then stability.

关 键 词：混凝土板桩 CEL方法 破坏模式 减阻措施 刃脚 钻孔 

分 类 号：TV332.2[水利工程—水工结构工程]