某渡槽辅助墩加固有限元仿真分析

Finite Element Simulation Analysis of Aqueduct by Auxiliary Pier Reinforcement

以某渡槽为工程背景,建立辅助墩加固的空间实体有限元模型,考虑混凝土的材料非线性,对渡槽加固前后的各施工阶段进行受力分析,同时对比分析了不同顶升力大小对加固效果的影响。通过计算分析,可以得到如下结论:①采用辅助墩加固法可以显著降低渡槽的结构应力、变形以及裂缝宽度;②渡槽加固过程中采用适宜的顶升力可以增强加固效果;③顶升力由零逐渐增大,渡槽加固后的竖向位移先减小后增大,渡槽顶升后和加固后的主拉应力最大值同样呈现先减小后增大的变化趋势;④顶升力不宜过大,过大的顶升力容易造成渡槽跨中截面及其附近截面的上缘开裂,加固施工前需要对顶升力进行对比计算分析。

With an aqueduct as the engineering background,this paper establishes a finite element model of spatial entity by auxiliary pier reinforcement,analyzes the force of each construction stage before and after the aqueduct reinforcement with consideration to the material nonlinearity of concrete,and compares and analyzes the influence of different jacking forces on the reinforcement effect.Through calculation and analysis,the following conclusions can be drawn:①The structural stress,deformation and crack width of the aqueduct can be significantly reduced by auxiliary pier reinforcement method.②The reinforcement effect can be enhanced with a suitable jacking force during aqueduct reinforcement.③When the jacking force is gradually increased from zero,the vertical displacement of the aqueduct after reinforcement is reduced first and then increased,the maximum principal tensile stress of the aqueduct after jacking and reinforcement also shows a trend of decreasing first and then increasing.④The jacking force should not be too large.Otherwise,the upper edge of the aqueduct will easily crack at the mid-span position and its adjacent position.Comparative calculation and analysis of the jacking force is required before reinforcement construction.