不同填土高度下钢波纹管变形与力学性状的数值分析

利用FLAC3D对填土高度1~10 m下的钢波纹管涵进行模拟,研究不同填土高度下钢波纹管的变形和力学性状.研究结果表明:钢波纹管顶部节点竖向位移最大值在路堤中心断面处,且当填土高度大于6 m时,竖向位移沿轴向逐渐减小趋势较为明显;填土高度小于6 m时,钢波纹管水平位移沿轴向变化较小;填土高度大于6 m时,水平位移变化较为复杂,出现两个拐点;同一填土高度下,钢波纹管路堤中心断面上半部分和下半部分60°~90°范围内弯曲应力较大,水平向弯曲应力最小,且上半部分与下半部分受力状态基本一致;路肩断面上半部分弯曲应力值基本不变,下半部分从0°~-90°范围内弯曲应力逐渐增大,且-60°~-90°范围内弯曲应力值较大,最大值出现在管底处;钢波纹管管顶轴向弯曲应力最小值出现在路肩断面处,最大值出现在路肩至管口范围内;当填土高度大于4 m时,水平节点轴向弯曲应力最大值出现在路肩至管口范围内;管底轴向弯曲应力最大值出现在路肩断面处.

Numerical Analysis for Mechanics and Deformation Properties of Steel Corrugated Pipe Culvert Under Different Embankment Height

Using FLAC3 Dto simulate the steel corrugated pipe culvert with embankment height between 1 m to10 m,we studied the mechanics and deformation properties of steel corrugated pipe culvert under differentembankment height. The study results showed as follows. The maximum value of vertical displacement of steelcorrugated pipe at the top of the nodes appear in the center of the embankment section,and when the embankmentheight is more than 6 m,the decreasing trend of vertical displacement along the axial direction is more obvious.When embankment height is less than 6 m,the horizontal displacement along the axial of steel corrugated pipechanges smaller while,when embankment height is more than 6 m,the change of horizontal displacement iscomplex,and appeared two inflection point. Under the same embankment height,the bending stress of the upperpart and the lower part within 60°-90° of the embankment center section of steel corrugated pipe is larger,while thebending stress of horizontal is the least,and the status of the stress between the upper part and the lower part is almost the same. The value of bending stress of the shoulder of embankment of the upper part is almost unchanged.The bend stress of its lower part range from 0°--90° increases gradually,and the value of bending stress rangefrom-60°--90° is bigger,and the largest value appeared in the bottom of the tube. The least value of the bendingstress along axial of steel corrugated pipe appeared in the section of the embankment shoulder,and the largest valueof bending stress appeared in the range from the embankment shoulder to the nozzle. When the embankment heightis more than 4 m,the largest value of bending stress along axial of the level node appeared in the range from theembankment shoulder to the nozzle. The largest value of bending stress along axial of the bottom of the tubeappeared in the section of embankment shoulder.