谱元法和有限元法的路表弯沉计算对比

Comparison of Calculations of Road Surface Deflection by Spectral Element Method and Finite Element Method

以落锤式弯沉仪产生的冲击载荷作用于路表为工况,将公路的面层、基层和土基均假设为线弹性材料,并利用有限元软件建模、划分网格、设定边界条件进行加载和计算。同时介绍了谱元法计算路表弯沉时处理边界条件的问题。基于谱元法的路表弯沉计算理论,采用自编语言求得路表弯沉时程曲线。将谱元法得到的弯沉曲线与有限元计算曲线作比较,得出了两者在弯沉计算结果上基本吻合,同时分析了两者0mm处测点最大弯沉差值,验证了谱元法对路表弯沉计算问题的正确性;在前处理上,谱元法无需像传统有限元那样划分许多网格,从而大大减少了计算量;在计算时间上,得出谱元法在计算效率上明显优于有限元法。

Taking the impact load produced by falling weight deflectometer on the road surface as the working condition,the surface layer,base layer and soil foundation of the highway are assumed to be linear elastic materials.A finite element software is used for modeling,meshing,boundary condition loading and calculation.At the same time,the problem of boundary condition processing in calculating road surface deflection by the spectral element method is introduced.Based on the theory of the spectral element method,time-history curve of road surface deflection is obtained by self-compiling language.The bending curve obtained by the spectral element method is compared with the curve calculated by the finite element method,and the results are basically consistent with each other.Meanwhile,the maximum bending error between the two curves at the measuring point of 0 mm is analyzed,which verifies the correctness of the spectral element method in the calculation of the problem of road surface deflection.In the pre-processing,the spectral element method does not need to divide many grids like the traditional finite element method,which has greatly reduced the amount of calculation.In terms of calculation time,it is concluded that the spectral element method is obviously superior to the finite element method.