低速冲击下混凝土板的能量耗散研究

Energy dissipation of concrete slabs under low-speed impact

针对混凝土板类构件在低速冲击作用下能量耗散的问题,采用落锤装置对6组混凝土板试件进行低速冲击试验。结合弹性力学理论计算了试件的弹性变形能,并通过能量守恒定律得出试件塑性变形能,分析了混凝土强度和落锤冲量对混凝土板破坏能量耗散的影响。结果表明:在低速冲击下混凝土板所吸收能量的98%都通过塑性变形能的方式消耗;混凝土强度不能完全决定受低速冲击混凝土板塑性变形能的耗能,混凝土板的塑性变形能随冲击能量的增大而增大,并呈现很好的线性关系。该研究可对提高混凝土板类构件在低速冲击作用下的防护能力提供参考,以供防护工程设计所需。

Here,aiming at the problem of energy dissipation of concrete slab components under low-speed impacts,tests for 6 groups of concrete slab specimens were conducted under low-speed impact with a falling hammer device.Elastic deformation energy of specimens was calculated based on the elastic mechanics theory,and plastic deformation energy of specimens was obtained with the law ofenergy conservation.Effects of concrete strength and falling hammer impulse on energy dissipation of concrete slab failure were analyzed.The results showed that 98%of the energy absorbed by concrete slab under low-speed impact is dissipated through plastic deformation energy;concrete strength can’t completely determine energy dissipation of plastic deformation energy of concrete slab under low-speed impact;plastic deformation energy of concrete slab increases with increase in impact energy,and both of them have a good linear relation;this study can provide a reference for improving protective ability of concrete slab components under low-speed impact;it is necessary for design of protective engineering.