A Method Research For Cost Optimization Of Maintenance And Repair Measures For Bridge Pier Based On Stochastic Simulation

Considering the security and applicability, life cycle cost analysis could optimize the maintenance budget and plan, which is currently becoming a very important technique solution to avoid the maintenance cost surging or even security problems and shows great significance.The cost of maintenance and repair measures for piers in marine environment through Monte Carlo simulation is calculated in order to minimize the maintenance cost based on the chloride diffusion model and life cycle cost analysis method in the first main part of the present work. It is including:(1) Stochastic prediction for the service life of Qingdao Bay Bridge piers;(2) Stochastic simulation for single maintenance or repair measure;(3) Stochastic simulation for composite measures;(4) Cost analysis for comprehensive measures is compared.Combined with the mechanism of maintenance and repair measures, the method takes into account the randomness of chloride diffusion and establishes a complete cost calculation process for the maintenance program. By the cost result, the decision-makers can select specific maintenance and repair plan for their own project. In addition, the method can provide reference for maintenance budget.A life cycle cost analysis method for maintenance measures based on concrete carbonation theory and inspection technique for piers of inland bridge is also established. The method can be divided into three steps:(1) Simulate the carbonation process of the pier by Monte Carlo method;(2) Establish the inspection accuracy model;(3) Calculate the maintenance and repair cost expectation according to the incorporation of steel corrosion model and event tree illustration.The method takes into account the randomness of carbonation process and the accuracy of inspection, which can be used for the comparison of maintenance measures, the choice of inspection instrument and the interval of inspection. The decision-maker can optimize the maintenance measures and minimize cost under the premise of maintaining an acceptable reliability index for the bridge using the above methods.