Study On Safety Analysis Method Of Inland High Pile Frame Wharf Based On Reliability Theory

High-piled frame wharf is one of the structure forms of high-piled wharf and has good integrity and high rigidity,with its upper part of frame structure.It is applicable to inland river ports varying greatly in water level and requiring layered mooring line.The lower structure of high-piled wharf is permeable,which can easily cause accumulation of moisture.Thus the high-piled wharf is vulnerable to chemical erosion and physical damage during the use.And we can determine whether the structure should be reinforced and reconstructed through analysis of reliability of the structure system to avoid safety accidents caused by the damage to the structure.The paper applies the finite element analysis software ANSYS and numerical calculation software MATLAB to analyze system reliability of a certain inland river's high-piled frame wharf based on ultimate bearing capacity of the overall structure,with the main content as follows:(1)Builds a parametrical finite element model when there is damage to the structure and a parametrical finite element model when there is no damage to the structure.Then the paper calculates ultimate bearing capacity of the overall structure of the high-piled frame wharf in the case of cargo load.And accuracy of the calculation results can be verified by drawing the load displacement diagram.Through comparing the calculation results,it is found that there is a dramatic decline in ultimate bearing capacity of the overall structure if there is damage to the structure.(2)Using the method that combining nonlinear finite element analysis and calculation with Monte Carlo statistical simulation method,the paper selects random samples of factors influencing ultimate bearing capacity to simulate samples of ultimate bearing capacity of the overall structure of the high-piled frame wharf in the case of cargo load.Through.the analysis of the samples by means of MATLAB,it is obtained that the ultimate bearing capacity samples obey normal distribution no matter whether the structure is damaged or not.(3)Then reliability can be analyzed by taking ultimate bearing capacity as random resistance variables in the integrated structure reliability function based on the statistical parameters of the ultimate bearing capacity calculated by Monte Carlo statistical simulation method.It is found that there is a dramatic decline in reliability index when there is damage to the structure,but this still meets requirements of the specification(4)Based on the Response surface methodology.The paper first takes factors influencing the ultimate bearing capacity as input parameters to calculate ultimate bearing capacity of the overall structure of the high-piled frame wharf,and then uses ultimate bearing capacity as an output parameter to fit a responding surface function.This function and load effect can be combined to form the high-piled frame wharf system reliability function.And the reliability index and checking point which the calculation precision is achieved the engineering requirement can be calculated using the method of checking point to solving reliability.