Stability Analysis Of Sluice Chamber On Soil Foundation And Optimization Of Bottom Plate Size

The sluice chamber is the main body of the sluice project,and the stability of the sluice chamber plays an important role in ensuring the function and benefit of the sluice.The bottom plate is the foundation of the sluice chamber,and its size and structure determine the stability and safety of the whole sluice project.In our country,the large and medium-sized sluices built on the soil foundation mostly adopt the integral structure which connects the pier and the bottom plate,and the floor engineering quantity of this structure accounts for a large proportion of the total engineering quantity.Therefore,it is necessary to carry out stability analysis and floor size optimization of sluice chamber on soil foundation.Taking the sluice on the soil foundation as the research object,this paper studies the stability of the sluice chamber and the optimization of the floor size.The main contents of this paper are as follows:(1)According to the design code of sluice,the safety factor of anti-sliding stability,maximum base stress,minimum base stress and non-uniformity coefficient are selected as the evaluation index of sluice chamber stability,and the corresponding influencing factors are selected.Then the sample data of influencing factors are constructed by sampling method.The sensitivity coefficient is calculated based on BP neural network.And the data fitting by Garson algorithm.Thus the sensitivity analysis method of influencing factors of sluice chamber stability is established.Based on the sensitivity analysis method of factors affecting sluice chamber stability,the factors that have greater and less influence on the evaluation indexes of sluice chamber stability are selected.Different sampling methods and different forms of probability distribution of influencing factors have little influence on the above screening results.On this basis,the effects of different loads on the stability of the sluice chamber under the conditions of design water level and check water level are analyzed Under the two working conditions,the dead weight of the structure and the water load play a decisive role in the stability of the sluice chamber.The silt pressure and wind pressure have little influence on the stability of the sluice chamber,while the wave pressure has a great influence on the stability of the sluice chamber.(2)Based on the statistical analysis of the literature on the structure of sluice chamber by finite element method,the statistical results are analyzed by comparative study.The main assumptions in the finite element analysis model of sluice chamber stability are determined,including:the dimension of the model is two-dimensional plane,the constitutive model of sluice chamber is linear elastic model,the constitutive model of foundation is M-C equation model,and the contact between sluice chamber and foundation is simulated by thin layer element.The loads applied under the working conditions of design water level and check water level are as follows:dead weight of structure and equipment,hydrostatic pressure of upstream and downstream,upstream and downstream water weight,uplift pressure and wave pressure;the size of foundation modeling is suggested as follows:the depth of foundation is taken to rock base,and the length of upstream and downstream of foundation is taken to twice the length of sluice chamber along the direction of flow;from the view of engineering safety,it is suggested that the improved resistance coefficient method should be selected as the calculation method of seepage pressure.(3)A mathematical model for optimal design of sluice chamber floor size is established.Under the condition of design water level and check water level,the research on the optimization of floor size based on the evaluation index of sluice chamber stability is carried out by using material mechanics method and finite element method as stress calculation method respectively.The results show that the factors influencing the optimization results of the two methods are different.In the optimization design,it is suggested that the two methods should be used for optimization,and the larger size of the optimization result should be selected to ensure the stability of the sluice chamber.Aiming at the problem of sluice chamber stability and floor size optimization,this paper comprehensively uses many theoretical methods,such as LHS sampling method,Gibbs sampling method,BP neural network,Garson algorithm,sensitivity analysis method,literature investigation and statistics,orthogonal test,genetic algorithm,optimal design method and so on.The factors affecting the stability of sluice chamber are analyzed and screened,and the finite element model of sluice chamber stability analysis is established.This paper explores the floor size optimization design based on the sluice chamber stability evaluation index,in order to provide some reference and technical support for the sluice chamber stability analysis and floor size optimization design.