同济大学Ansys隧道荷载结构法算例

隧道荷载结构法算例1．问题描述：主要截面尺寸如图1所示，m2.5R1，mR8.82。内轮廓采用曲墙拱三心圆拱。弹性抗力系数取为35/105.1mkNk。衬砌厚度为0.6m，截面的物理参数如表所示。结构混凝土参数混凝土标号弹性模量E(kN/m2，kPa)惯性模量I(m4/m)截面积A(m2/m)25号混凝土28500000.0000.0180.600图1衬砌截面图图2荷载施加图图3衬砌剖分半结构图图4约束条件2．ANSYS计算在ANSYS中需要将荷载转化为节点荷载，需要输出ANSYS结点坐标，用Excel计算等效节点荷载。节点号X(m)Y(m)DX(m)DY(m)FX(kN)FY(kN)Length(m)Spring(kPa/m)105.21.2494564-31.7132776455.632923-1.01455.1000831.01450.0999174.9498095-62.20741.019408439152910.13824-1.994.8041740.97550.295919.7094006-58.596871.019393404152907.12325-2.8894.3236420.8990.48053214.095865-52.735621.019368238152906.56426-3.6773.6769550.7880.64668717.940633-44.8455961.019385951152903.18987-4.32362.8889650.64660.7879921.095953-35.2362721.019323246152905.03198-4.80421.9899540.48060.89901123.440567-24.273391.019410512152908.94269-5.10011.014470.29590.97548424.884373-12.3727081.019375389152906.40192-5.200.09991.0144721.783213-4.06381.019376635131061.720711-5.1699-0.727490.03010.72749118.13225-3.7605780.728112974109217.329810-5.0797-1.450.09020.7225099.0349807-2.8196520.72811808954608.8567建立局部柱坐标系，施加径向弹簧（用PSPRNG命令）。根据计算结果中弹簧是否收拉，对结果进行迭代计算。第1次计算结果如下图所示。图5结构变形图删除受拉弹簧后的计算结果如下图。图6删除受拉弹簧后的结构弯矩图命令流：/prep7et,1,beam3mp,ex,1,2.85e10mp,prxy,1,0.25r,1,0.6,0.018,0.6k,1,0,5.2k,2,-5.2,0k,3,-5.0797,-1.45k,4,0,0k,5,3.6,0larc,1,2,4,5.2larc,2,3,5,8.8lesize,1,,,8lesize,2,,,2lmesh,all/pnum,node,1nplotnlist!computenodalforceinexcelf,1,fx,1.249456357f,3,fx,4.949809522f,4,fx,9.709400641f,5,fx,14.09586494f,6,fx,17.94063305f,7,fx,21.0959527f,8,fx,23.44056671f,9,fx,24.88437284f,2,fx,21.78321251f,11,fx,18.13225f,10,fx,9.03498073f,1,fy,-31.71232203f,3,fy,-62.20595732f,4,fy,-58.59673052f,5,fy,-52.73566421f,6,fy,-44.84799591f,7,fy,-35.23684427f,8,fy,-24.27156046f,9,fy,-12.3735342f,2,fy,-4.065284813f,11,fy,-3.760578f,10,fy,-2.818684269!definelocalcoordinatesystem1local,11,1,0,0,0csys,11!applyspringpsprng,1,tran,7493.740645,1psprng,3,trans,29686.98234,1psprng,4,trans,58233.1106,1psprng,5,trans,84541.37308,1psprng,6,trans,107600.758,1psprng,7,trans,126525.1061,1psprng,8,trans,140587.1654,1psprng,9,trans,149246.5385,1psprng,2,trans,130647.0163,1!definelocalcoordinatesystem2local,12,1,3.6,0,0csys,12!applyspringpsprng,11,trans,439373.7158,1psprng,10,trans,384811.9249,1!switchtodefaultcartesiancoordinatesystemcsys,0!applyboundaryconditiond,1,ux,0d,1,rotz,0d,10,ux,0psprng,10,trans,150000,0,-1finish/solusolvefinish/post1pldisp,1!checkspringswithtraction(+meanstraction)etable,sforce,smisc,1pretab,sforce!deletespringswithtractionsandrecalculatehere!etable,m1,smisc,6etable,m2,smisc,12plls,m1,m2,-1练习题：如下图所示的无仰拱拱形衬砌，用ANSYS计算结构内力。结构几何尺寸如下：圆心坐标（0，1.75），衬砌厚度0.3m，半径R=5.1539m，圆心角φ=112°13′54″，围岩为III级，弹性反力系数K=400MPa/m。衬砌材料=23kN/m3，弹性模型E=32GPa，泊松比=0.25。单元划分左右圆弧各划分20个单元，总计40个单元，41个结点。约束条件：对墙角水平、竖直方向约束。