基于CEL法的沉管挤淤残余厚度数值分析  

Study of residual height of mud squeezed under submerged tubes by CEL Method

作　　者：杨玮宸 邱长林[1] 闫澍旺[1] YANG Wei-chen;QIU Chang-lin;YAN Shu-wang(School of Civil Engineering,Tianjin University,Tianjin 300072,China)

机构地区：[1]天津大学建筑工程学院,天津300072

出　　处：《水道港口》2021年第4期530-537,共8页Journal of Waterway and Harbor

基　　金：国家自然科学基金资助项目(41272323)。

摘　　要：沉管隧道施工过程中基槽内容易产生回淤,当回淤超过一定厚度时沉管隧道将无法正常对接,此时需要提前清淤。针对目前沉管隧道施工中清淤标准不统一的问题,文章通过黏度计研究了淤泥的流变特性,采用Herschel-Bulkley流变模型描述其剪切流变特性。在此基础上建立了采用CEL有限元法模拟沉管挤淤过程的数值分析方法,并通过对比数值计算结果和沉管挤淤小比尺室内模型试验结果验证了该CEL数值方法的可靠性。利用该数值分析方法研究了某实际工程在不同淤泥容重下初始回淤厚度与最终夹泥厚度关系,建立了最终夹泥厚度小于0.5 mm时淤泥容重与其对应初始回淤厚度之间的关系曲线,根据该曲线为沉管隧道施工中不同隧道底部压强作用下的清淤标准提出参考。The back siltation of foundation trench is easily formed during the construction of submerged tunnels.When the back siltation accumulates to some height,the submerged tunnels could not dock properly.In this case,it is necessary to desilt in advance.Because there is no consistency about the criterion for desilting,this paper studied the rheological properties of the silt using viscometer and employed Herschel-Bulkley model to describe its shear rheological properties.Based on this model,the CEL finite element method was established to simulate the silt squeezing of immersed tube and verified by comparing the result of CEL analyzed with those of small scale model tests of squeezing.Using the CEL numerical analysis method,the relationships between the initial and the final silt thickness under different pressures and mud densities were further studied.Based on the numerical analyses,the curves focused on the mud density and the initial silt thickness are established where the thickness of residual silt is less than 0.5 mm.The desilting criterions for practical engineering under different pressure are proposed based on this curve.

关 键 词：沉管隧道 回淤 CEL数值方法 清淤标准 

分 类 号：U459[建筑科学—桥梁与隧道工程]