Research On Wetting Deformation Of Earth-rock Dam Based On P-Z Model

Earth rock dam is widely used because of its strong applicability to terrain,convenient constructio n and easy material selection.With the large-scale application of earth rock dam,the problem of dam deformation is also prominent.Dam deformation is an important problem in the design,operation and management of earth rock dam.At present,the research of wetting is mostly based on elastic nonlinear model,and the influencing factors of wetting are complex.There is no clear formula for wetting deformation of coarse-grained materials.In order to establish a wetting deformation model for coarse-grained materials and further apply it to numerical analysis.The main work of this paper is as follows:1: Through the indoor compression test of coarse aggregate,the ultimate compressive strength of coarse aggregate under the confining pressure of 800 kpa,1600kpa and 2400 kpa was measured,and on this basis,the humidification level of 0.2,0.4,0.6 and 0.8 was tested.Based on 12 sets of data of 3 confining pressures and 4 wetting levels,the wetting deformation formula is obtained by fitting.2: Taking the generalized plastic model as the constitutive model of coarse aggregate,the empirical parameter a of the generalized plastic model is optimized by EMD decomposition and cloud theory.Based on the optimized generalized plastic model,the numerical simulation of the indoor compression test is carried out to verify the applicability of the optimized generalized plastic model to the deformation calculation of coarse-grained materials.3: By combining the optimized generalized plastic model with the humidification formula,the humidification deformation model based on the generalized plastic model is obtained.The model is used to restore the humidification test and to simulate the humidification data to verify the rationality of the humidification model.4: Taking Yanshan Reservoir as an example,on the basis of finite element method,the model is used to calculate and analyze the deformation process of Yanshan Reservoir.The results show that: The humidification formula can be divided into t he humidification axial strain formula and the humidification body strain formula.The humidification parameter is introduced into the formula and its physical meaning is explained.Compared with the experimental results,the maximum volume strain error of the two models is 13.23%,and the maximum axial strain error is 13.64%.The maximum error of simulation compression test is 9.5%,the results are less than 15%,and the fitting degree is good.The EMD decomposition method and cloud theory method are used to modify the parameter a.The results show that the entropy error of a is reduced by 35%,and the super entropy error rate is reduced by 67%.The wetting model is applied to the calculation of the wetting deformation of Yanzhuang reservoir.The results show that the settlement of the wetting deformation is 0.08 m,accounting for 31% of the total settlement.The calculation of wetting deformation and maximum deformation of Yanzhuang reservoir by wetting model is within a reasonable range.In this paper,the calculation parameter a of the generalized plastic model is modified to provide a reference for the optimization method of other parameters in the generalized plastic model,which makes the fitting of the generalized plastic model to the stress and strain of coarse aggregate more accurate and widely used.Based on the optimized generalized plastic model,the model of wetting calculation provides a theoretical reference for the finite element calculation of wetting deformation of coarse aggregate in the future.