A Scale Effect Study Of Rockfill Materials Based On FDEM

At the present stage,the demand for the construction of high rockfill dams is increasing,and it is very important to study the mechanical properties of rockfill dam materials.In the construction level under the current conditions,the maximum diameter of rockfill can exceed 1 meter.It is very difficult to meet the requirement when tests in the laboratory using the primary distribution.Therefore,in the indoor test must be carried out with a certain degree of scale,and the primary distribution rockfill materials can be simulated in certain degree.After grading,the grading of rockfill has changed obviously,and the relationship between the filling of rockfill particles has also changed.There is a big difference between the mechanical properties of the scaled rockfill materials and primary distribution rockfill materials,which produce the scale effect.A numerical simulation of Shuibuya dam’s rockfill material is taken in this passage.The discontinuous stochastic particle methon considering particle breakage has been taken.The main work is as follows:(1)An introduction of the discontinuous stochastic particle methon considering particle breakage.Stochastic modeling technique is used to generate random rockfill particles and their distribution in space.An introduction of the SPG procedure which produce the random particle model.A simple and convenient method for particle invasion is introduced to improve the efficiency of particle formation.A simulation method for particle breakage of rockfill materials based on cohesive zone model and rock deterioration model.(2)The influence factors of size effect were analyzed.The strengths of rock aggregates with different sizes were measured.The distribution and effect size on the strength were investigated by Weibull statistics.The influence of the size effect of the particle strength on the scale effect of the laboratory test is studied by using the FDEN method.The mechanisiri of size effect in laboratory test was revealed from the meso level.(3)Relying on the Shuibuya CFRD dam materials,the typical material partition(the main rockfill zone,secondary rockfill zone)rockfill numerical shear test has been taken.The parameters of Duncan-chang models has been sorted according to the three axis test curve of primary distribution rockfill.Based on the Duncan-chang model parameters obtained from the laboratory tests and numerical tests,the stress and deformation of the dam are simulated and analyzed.