The macroscopic damage image of reinforced concrete slabs under impact effect are obtained through model test, and the residual velocity of the projectile are gained from the tests.
After reflection, the average particle velocity near free surface is equal to twice the piston velocity approximately, which agrees with macroscopic phenomena.
激波在自由面反射后,自由表面附近的粒子速度为活塞速度的二倍,这和宏观力学结果相同。
3
Consequently, at the macroscopic crack branching velocity, the experimental fracture surface energy and the fracture surface roughness; have no single value in such materials.