循环荷载作用下埋地管道力学与变形性能研究  

Mechanical and Deformation Performance of Buried Pipes Under Cyclic Loading

作　　者：孙文君 肖成志 王嘉勇[2] 何晨曦 宋杨 SUN Wenjun;XIAO Chengzhi;WANG Jiayong;HE Chenxi;SONG Yang(Hebei University of Water Resources and Electric Engineering,Cangzhou,Hebei 061001,China;School of Civil and Transportation Engineering,Hebei University of Technology,Tianjin 300401,China;Technology and Research Center of Civil Engineering,Hebei Province,Tianjin 300401,China)

机构地区：[1]河北水利电力学院,河北沧州061001 [2]河北工业大学土木与交通学院,天津300401 [3]河北工业大学河北省土木工程技术研究中心,天津300401

出　　处：《公路工程》2018年第5期61-68,共8页Highway Engineering

基　　金：国家自然基金项目资助(50909032);河北省省级科技计划自筹经费项目(16275419);河北省自然基金项目资助(E2018412002);河北省高等学校科学技术研究项目(Z2017034)

摘　　要：针对循环荷载作用下埋地管道力学与变形性能开展试验研究,综合分析管道埋深(H)、管壁厚(t)、荷载水平(P)、加载频率(f)和循环次数(n)等因素对管道性能的影响。试验结果表明:同等条件下增加管道埋深可有效减少地表循环荷载对管道径向变形和管周土压力影响,管顶土拱效应使管顶竖向土压力明显大于管顶,且管道水平径向距管中心2D～4D范围内水平土压力明显大于竖直土压力;管壁厚增加51. 4%时,管道垂直和水平径向变形比分别减少了43. 3%和35. 7%,且管道上腰部由受压过渡为受拉状态,且过渡区随管壁厚增加而向管顶附近移动;提高循环荷载水平或降低荷载循环频率,管道变形、加载板沉降、管周土压力以及管周应力都明显增加,表明相同循环次数时高水平或低频率循环荷载对埋地管道影响更为显著;随着循环次数增加,管道径向变形比和管周土压力初期迅速增长,加载后期逐渐趋于稳定或出现回落,加载板沉降持续增加,埋地管道向着加载板地基破坏的趋势发展。Comprehensive tests,under consideration of the effect of buried depth,H,pipe’s wall thickness,t,load level,P,load frequency,f,and cycles of load,n,on the mechanical and deformation performance of buried pipes,were carried out.The tests results showed that increasing the buried depth of pipes while keeping other parameters identical can effectively weaken the radial deformation and earth pressure around pipes,and soil-arching effect results in greater earth pressure in crown of pipes than in bottom of pipes.The affecting zone where horizontal earth pressure is greater than ones in vertical direction ranges from 2 D to 4 D.Increasing the wall thickness by 51.4%,the ratios of vertical deformation to external diameter and horizontal deformation to external diameter decreased 43.3%and 35.7%,respectively.Strain condition for upper waist of pipes can be transferred from compression to tension condition,and the tension area tends to move towards crown of pipes.With the increase of level of cyclic loading or lowering load frequency,the radial deformation and strains of pipes,settlement of loading plate,and earth pressure around pipes decrease remarkably.That demonstrated high level of load and lower frequency can be the important factors for affecting the deformation performance of buried pipes.Increasing the cycles of load,radial deformations and earth pressures increase immediately at the very beginning,and then tend to be stable,the settlement of load plate,however,increases continuously,thereof the failure mode of buried pipes subjecting to cyclic loading prefers to foundation failure for loading plate.

关 键 词：埋地管道 模型试验 循环荷载 力学性能 

分 类 号：TU43[建筑科学—岩土工程]