Numerical Simulation Of Rockfill Concrete Tensile And Compression Test Based On Meso-Modeling

From the perspective of meso-structure,this paper regards rockfill concrete as a composite material formed by the combination of rockfill and self-compacting concrete,and establishes a three-dimensional finite element model using MATLAB and ANSYS/LS-DYNA software,and then performs Numerical simulations of compressive test and split tensile test of rockfill concrete model are presented.The effects of strain rate,bond strength of rockfill concrete,and stone size on the compressive strength and splitting tensile strength of rockfill concrete are discussed and analyzed.The conclusion is as follows: The compressive strength of rockfill concrete increases with the increase of strain rate.It increases as the bonding strength increases.And it increases with the increase of rock size.However,the growth rate is different.The compressive strength of rockfill concrete is more sensitive to strain rate.Under the same other conditions,as the strain rate increases,the compressive strength of the specimen is greatly improved;otherwise,it decreases.The compressive strength of rockfill concrete specimens is less sensitive to the bond strength.Under the same other conditions,with the increase of the bonding strength,the increase of the compressive strength of the sample becomes smaller;the sensitivity to the particle size of the stone is also lower.Under the same other conditions,as the strain rate increases,the increase in the compressive strength of the sample is smaller.The splitting tensile strength and compressive strength of rockfill concrete show the same law:it increases with the increase of strain rate,and the influence is greater.As the bond strength increases,its increase is smaller.The overall intensity value is relatively small.Under the same circumstances,the split tensile strength is only about 1/6 of the compressive strength.In the compressive strength test,the failure phenomenon is that the failure of the specimen has obvious levels.Within a certain depth close to the load,the self-compacting concrete of the stone is very seriously damaged in a crushing state,and the part far away from the loading end.The damage of stones and self-compacting concrete is minimal.In the transition section in the middle part,the damage is relatively small,and presents the characteristics of local damage,and the damage is mainly cracks.In the split tensile test,the failure phenomenon is that in the initial stage,the failure first occurs at the positions of the top and bottom gaskets.Due to the effect of inertia,the difference in force between the upper and lower gaskets is relatively large.The force is significantly greater than that of the lower part.The mortar is seriously damaged,and the interface between the mortar and the rockfill is seriously damaged.On the side near the top surface,longitudinal cracks appear,and the other parts of the specimen remain basically intact.