Numerical Simulation of Multi-Hazard Joint Action on Mountainous Road Bridges
Mountainous road bridges are subjected to hydrological hazards such as scour and erosion in a long term of years,and they may concurrently suffer geological hazards like falling rocks.To elucidate their structural response and damage mechanisms under multiple hazards,the interpolation algorithms for the transfer of scour and erosion data were derived from the aspect of fluid-structure coupling.In addition,combined with the birth-death element functionality,a numerical simulation method for the multi-hazard joint action on mountainous road bridges was for-mulated by means of Delaunay triangulation and collaborative interpolation of feature points.First,aimed at the scour data,a scour data transfer equation was constructed based on the linear interpolation theory within a triangle.Second,supplementary data transfer equations based on three-dimensional surface Delaunay triangulation and the linear interpolation theory outside the triangle were derived for the erosion and flow force data,and the feature point collaborative interpolation algorithm was utilized to calculate the overall result of structural-domain target cells.Fi-nally,based on the birth-death element functionality and with the consideration of scour and erosion morphology of pile foundations within the structural domain,the numerical model of a mountainous road bridge's pier column im-pacted by falling rocks was established under conditions of scour and erosion.Results demonstrate that the interpola-tion methods for the data of scour and erosion models achieve a high accuracy.Under conditions of different impact velocities,different impact angles and different masses of falling rock,the relative changes in peak impact forces under the scour and combined scour-erosion conditions exhibit nonlinear characteristics compared with those under the condition of falling rocks alone.Moreover,the pile foundation erosion also exerts a nonlinear effect on the peak im-pact force under the scour conditions.As the impact velocity and mass of falling rock increase,the peak displace-ments at the impact point all increase under different conditions,and they are in a descending order under conditions of scour,combined scour-erosion and falling rocks alone.Meanwhile,under various conditions of impact velocity,impact angle and mass of falling rock,the erosion-induced peak displacements are reduced by up to 2%,11%and 4%,respectively.
multi-hazardtriangulationcollaborative interpolationbirth-death elementnumerical model
万方数据
维普
