强冲击荷载作用下加无粘结预应力筋格栅坝动力响应分析

泥石流拦挡坝主要以增加自身刚度来提高其拦挡能力,但对于巨石块的碰撞,坝体刚度越大,其受冲击力也越大,相应的坝体结构破坏也越大。创新性地将无粘结预应力筋设置在普通格栅坝中,利用ABAQUS软件对普通格栅坝和加无粘结预应力筋格栅坝在相同冲击条件下(以10m/s的冲击速度)坝体被撞后动能的变化、加速度响应值、位移值和Von-mises应力进行了有限元数值模拟计算与对比分析。结果表明:加无粘结预应力筋格栅坝比普通格栅坝能吸收更多的冲击能量,冲击方向的加速度响应值更小,具有更好的抗冲击性能。

Dynamic Response of Grille Dam with Unbonded Prestressed Tendon under Strong Impact Load

The resistance ability of debris dam is mainly increased by improving stiffness of the dam.How-ever,under the impact of stones,the bigger the dam’s stiffness is,the bigger impact force it bears,and the greater structural damage it gets.Based on this point,this paper innovatively sets unbonded prestressed tendon in the ordinary grille dam,and conducts the finite element numerical simulation and comparison a-nalysis of the ordinary and improved grille dam by applying ABAQUS software.Under the same impact condition with impact velocity of 10 m/s,the paper compares the grille dams before and after the impact from the aspects including changes of kinetic energy,acceleration respon sevalues,dam displacement and Von-mises stress.The result shows that the grille dam with unbonded pestressed tendon absorbs more im-pact energy,and the acceleration response value is smaller.The grille dam with unbonded pestressed tendon exhibits better performance in impact resistance.