Optimization Design And Structural Analysis Of Prefabricated Channel Troughs In Xixiayuan Water Transmission Project

China is a big agricultural country,and irrigation is the top priority of the country.The characteristics of prefabricated trenches without grading save land resources,and the characteristics of unified processing in the prefabricated plant reduce the pollution of the construction site,which is in line with China’s green development policy,and research on this is necessary.The cross-sectional size design and steel bar dosage of prefabricated trench structure have a great influence on its cost.Therefore,a reliable and reasonable structural optimization design method should be selected to reduce the cost and economy of the prefabricated trench structure.At the same time,it is also necessary to ensure that the optimized design parameters can meet the force performance of the prefabricated channel during normal use.Based on the mature MATLAB toolbox,this paper optimizes the selected design variables according to the integration objective function and constraints of Xixiayuan Water Transmission Project,and uses ABAQUS software to establish the corresponding threedimensional assembly trench model to verify whether its mechanical properties meet the operational needs.The following aspects of research have been carried out.Familiar with the principle and operation process of standard genetic algorithm,introduce the method of genetic algorithm construction fitness function and constraint treatment.The prefabricated trench of Xixiayuan Water Transmission Project was simplified into a mathematical model,and reasonable channel section parameters and steel bar parameters were selected as the design variables of the optimization model,and a total of 5 section parameters and 4 steel bar parameters were screened out as design variables.Considering the hydraulic constraint,strength constraint,crack resistance requirement and reinforcement ratio of the prefabricated trench,a total of 12 relevant constraints were obtained by finishing and transformation.The cost of the trench body per unit length is determined as the objective function of the optimization function.The objective function and constraint are integrated into the GA function to optimize and solve the prefabricated trench.The optimized objective function value and its corresponding design variable value are obtained,that is,the engineering cost of the unit length of the prefabricated trench and the corresponding section parameters and rebar parameters.Through the comparative analysis of the optimization results,the results show that the amount of concrete and the amount of steel bar have been reduced to a certain extent,of which the amount of steel bar is reduced by 11.1%,the amount of concrete is reduced by 5.6%,and the cost of the optimized unit length trench is reduced by 6.9%,and the optimized economic benefits are ideal.Combined with the optimized cross-sectional size and rebar parameters,ABAQUS software is used to establish the corresponding three-dimensional finite element model of the prefabricated trench,mesh it,and then apply constraints and loads to the model.The static calculation and analysis,modal analysis and seismic wave transient analysis are carried out,and the calculation results show that the prefabricated trench can meet the requirements of various mechanical properties.