Concrete dams are reliable when subjected to static loads such as earth pressure and water pressure.However,the dam failure would be abrupt and catastrophic if it is impacted by boulders.This study simulated the dynam...Concrete dams are reliable when subjected to static loads such as earth pressure and water pressure.However,the dam failure would be abrupt and catastrophic if it is impacted by boulders.This study simulated the dynamic response of flat dam,concave dam,and convex dam under the impact of boulders by using ANSYS/LS-DYNA finite element software.In the numerical simulation,the strain rate effect under the impact load is considered,and Holmquist-Johnson-Cook(HJC)model-a dynamic damage constitutive model is applied to concrete materials.Results show that the peak impact force of concave dam is minimum.Meanwhile,for different dam types(flat dam,concave dam,and convex dam)and impactor velocities(5,10,and 15 m/s),the impact force fluctuates with the height of the impact point and it reaches the maximum value when the height of the impact point is 2/3 of the dam height.Numerical simulation mainly considers different masses and velocities and obtains empirical formulae of impact force for three dam types.The established empirical formula for the flat dam is compared with the existing classical formula and several similar experimental tests.It was found that the newly empirical formulae are reasonable and effective,and it provides design suggestions for similar concrete dams.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.51778273)。
文摘Concrete dams are reliable when subjected to static loads such as earth pressure and water pressure.However,the dam failure would be abrupt and catastrophic if it is impacted by boulders.This study simulated the dynamic response of flat dam,concave dam,and convex dam under the impact of boulders by using ANSYS/LS-DYNA finite element software.In the numerical simulation,the strain rate effect under the impact load is considered,and Holmquist-Johnson-Cook(HJC)model-a dynamic damage constitutive model is applied to concrete materials.Results show that the peak impact force of concave dam is minimum.Meanwhile,for different dam types(flat dam,concave dam,and convex dam)and impactor velocities(5,10,and 15 m/s),the impact force fluctuates with the height of the impact point and it reaches the maximum value when the height of the impact point is 2/3 of the dam height.Numerical simulation mainly considers different masses and velocities and obtains empirical formulae of impact force for three dam types.The established empirical formula for the flat dam is compared with the existing classical formula and several similar experimental tests.It was found that the newly empirical formulae are reasonable and effective,and it provides design suggestions for similar concrete dams.
