Based on explicit dynamics and contact-collision theory

ANSYS/LS-DYNA program was used to finish multiple-parameters numerical simulation and contrastive analysis of the conventional debris flow-resisting gravity dams and new-style dams with braces under single sphere impact.The results show that with or without braces

failure modes of concrete dam bodies are all local concrete crush caused by regional stress surge under impact force

but braces make the stress distribution uniform of dam bodies and material utilization higher.Braces can significantly reduce the dynamic displacement on top surface of concrete dams

its decreasing amplitude of the maximal dynamic displacement is more than 30% and up to nearly 65%

so the stiffness of dam bodies is increased significantly

in addition

when the height of impact location is certain

the smaller braces spacing is

the smaller dynamic displacement on top surface of concrete dams is;If braces are set up

we can properly reduce the thickness of concrete dam bodies and consider its proportion to be 1/3;Impact force is mainly sustained by concrete dam bodies and its stiffness is significantly greater than the total stiffness of braces.The higher the impact location is or the smaller the braces spacing is

the lower the reaction force′s proportion on bottom surface of concrete dams is and the more significant the strengthening effects of braces are.