国内外规范梯度作用下铁路高墩温度效应研究

Research on Temperature Effect of Railway High Pier under Gradient of Domestic and Foreign Codes

为对比研究各国规范温度梯度作用下空心高墩的温度效应,以西北地区某铁路空心高墩为研究对象,建立其实体有限元模型,提取杆系单元中零号块两侧的内力作为梁体边界条件,将各国规范中箱梁竖向温度梯度作为空心高墩横向温度梯度,计算其温度效应。研究表明:正温度梯度作用下,英国、美国、德国规范温度梯度作用下的位移曲线基本一致,且墩顶位移最大,中国规范作用下墩顶位移最小;正、负温度梯度作用下 von Mises 应力沿墩高变化趋势相同,沿壁厚均由外向内逐渐减小,达到一定距离后趋于稳定,且截面高度越高,各国规范温度梯度作用下的稳定应力值趋于一致;反之,截面高度越小,应力沿壁厚的变化曲线相差越大。

In order to study the temperature effect of hollow high pier under the temperature gradient in different codes,the solid finite element model of a railway hollow high pier in Northwest China is established.The internal force on both sides of block zero in the bar system element is extracted as the beam boundary condition,and the vertical temperature gradient of box girder in different codes is taken as the transverse temperature gradient of hollow high pier to calculate the temperature effect.The results show that:under the positive temperature gradient,the displacement curves under the British,American and German codes are basically the same,and the pier top displacement is the largest,while the pier top displacement under the Chinese code is the smallest;under the positive and negative temperature gradients,the von Mises displacement curves are basically the same Mises stress has the same change trend along the pier height,and gradually decreases from the outside to the inside along the wall thickness,and tends to be stable after reaching a certain distance,and the higher the section height is,the stable stress values under the action of temperature gradient of national codes tend to be the same;on the contrary,the smaller the section height is,the greater the difference of stress change curve along the wall thickness is.