Study On Foundation Structure Bearing Capacity Evaluation And Reinforcement Technology Of The Railway Bridge

In recent years, with the rapid development of passenger dedicated line and high-speed railway construction, the capacity of existing railway bridge demand is higher and higher,especially for the lower structure bearing capacity requirement.Therefore, to analyze the railway carrying capacity of bridge foundation, put forward the corresponding reinforcement measures, to ensure that in the design of railway Bridges and life span of normal use.This article summarizes the current research achievements on bridge bearing capacity evaluation and reinforcement, on the basis of a super major bridge in the engineering background, detecting state of existing railway bridge, the structure of the lower bearing capacity evaluation, strengthening method, and the bearing capacity of the reinforced was analyzed, and the main research content is as follows:According to the example of engineering structure and tectonic characteristics of the river bed scouring is larger, the riverbed cross section measurement;Environmental vibration method is used to test the girder and piers lateral natural vibration frequency and damping ratio, to understand the working state of bridge structure.On this basis, set up and adjust the Midas finite element model of injured, according to the relevant rules, under different load combinations, the analysis part continuous beam bridge pier and the pile bearing capacity, and accordance with the requirements of the relevant rules and regulations, to determine the bearing capacity of the bridge.Inductive analysis commonly used bridge foundation reinforcement method, combining with the characteristics of bridge structure and construction, according to the mechanical and structural requirements, does not meet the requirements of bearing capacity of 16 # and 17 #pier and the pile for reinforcement.After reinforcement structure evaluation model is established and the 16 # and 17 # pier after reinforcement and bearing capacity of pile is checked, and assess its reinforcement effect and bearing capacity of structure after reinforcement.Before and after strengthened with the finite element software ANSYS to 17 # pier pile foundation pile caps in finite element simulation, and consider the pile and soil.Analysis of finite element calculation results, the internal principal compressive stress along the bridge pier with pile foundation pile caps is passed along, other areas have no obvious characteristic;Principal tensile stress distribution at the bottom of the pile caps, and mainly include the pile top 1 times the pile diameter range of reinforced pile caps.Along the bridge pier with pile foundation concrete within the scope of the main pressure, equivalent oblique compression bar;At the bottom of the pile caps, pile top 1 times the pile diameter within the scope of the reinforcement is equal to the pull rod.Pile caps internal stress transfer inaccordance with the characteristics of the space truss model, proposed the calculation model,for the future design of railway bridge pile foundation pile caps is calculated to provide the reference.