沉管隧道含淤碎石垫层压缩试验与颗粒流模拟研究  

Research on Compression Test and Particle Flow Simulation of Silted Gravel Cushion in Immersed Tunnel

作　　者：付佰勇 励彦德 FU Bai-yong;LI Yan-de(Department of Civil Engineering,Tsinghua University,Beijing 100084,China;CCCC Highway Bridges National Engineering Research Centre Co.Ltd.,Beijing 100088,China)

机构地区：[1]清华大学土木工程系,北京市100084 [2]中交公路长大桥建设国家工程研究中心有限公司,北京市100088

出　　处：《公路》2025年第2期342-347,共6页Highway

基　　金：国家重点研发计划课题,项目编号2018YFC0809602。

摘　　要：垫层回淤问题是影响沉管隧道基础施工及管节沉放的关键问题之一。依托深中通道沉管隧道工程,利用碎石垫层室内侧限压缩试验与PFC3D数值模型相结合的研究方法,分析了淤泥含量对碎石垫层的位移沉降等宏观影响规律,并从空隙率、接触强度、强接触力链等细观角度解释了淤泥影响的内在原因。研究表明:淤泥比重越大时,含淤碎石垫层空隙率降低程度、侧限压缩位移沉降量、强接触力链总数也越大;淤泥的存在起到的主要作用是减小了碎石垫层的接触弹性模量,当淤泥比重每上涨10%,含淤碎石垫层接触弹性模量相对于无淤泥时下降13%~21%;淤泥的存在起到的另一作用是弱化了颗粒间摩擦咬合能力,当淤泥比重越大,高应力状态下强接触力链总数变化值越大,颗粒空间重组现象越明显。The problem of cushion siltation is one of the key problems affecting the foundation construction and tube section sinking of immersed tunnel.Based on the immersed tunnel project of Shenzhen-Zhongshan Link Project,the research method of indoor confined compression test of gravel cushion and PFC3D numerical model are used.The macroscopic influence of silt content on the displacement and settlement of gravel cushion is analyzed,and the internal causes of silt influence are explained from the microscopic perspectives of porosity,contact strength and strong contact force chain.The results show that the larger the proportion of silt,the greater the reduction of void ratio,the settlement of confined compression displacement and the total number of strong contact force chains.The existence of silt plays a major role in reducing the contact elastic modulus of gravel cushion.When the proportion of silt increases by 10%,the contact elastic modulus of gravel cushion with silt decreases by 13%~21%compared with that without silt.The existence of silt plays another role in weakening the friction and interlocking capability between particles.When the proportion of silt is larger,the change of the total number of strong contact force chains under high stress state is larger,and the phenomenon of particle space recombination is more obvious.

关 键 词：沉管隧道 回淤 碎石垫层 压缩试验 颗粒流模拟 

分 类 号：U459.5[建筑科学—桥梁与隧道工程] TU442[交通运输工程—道路与铁道工程]