滚石冲击荷载下棚洞钢筋混凝土板动力响应研究

我国西部地区地势复杂，高山峡谷众多，特殊的地质地貌发育了大量滚石山地灾害，严重威胁山区人民的安全。一般认为，采用棚洞结构进行滚石灾害防治是最为有效的工程措施，然而，滚石对棚洞的冲击是一个复杂的动力过程，尤其表现在滚石与棚洞顶板的瞬态接触过程中。而目前国内外对此缺乏合理的计算方法，严重制约滚石棚洞结构的工程应用。为此，结合Olsson为求解正交各向异性复合板冲击问题所提出的动力控制方程，针对目前接触准则给出的接触定律与实际往往不符所带来的缺陷，通过引入数值压痕试验手段，提出了一种滚石冲击钢筋混凝土（RC）板动力响应问题的理论方法。结合算例，将该方法与Herzt理论解、动力有限元解进行了比较，结果表明：Herzt弹性理论解未考虑结构塑性变形影响，导致滚石冲击力偏大；而该方法得到的理论解与动力有限元计算结果较为接近。该方法不仅可用于滚石冲击荷载下棚洞RC板动力响应分析，同时为压痕试验在土木工程中的应用提供了一种有效的数值分析方法。

Study of dynamic response of shed reinforced concrete slab to impact load of rock-fall

In western region of China, there are numerous alpine valleys. The special topography develops a large numbers of mountain disasters of rock-fall. It badly threatens the safety of people. Generally, the shed is the most effective engineering method. However, the impact behavior of rock shed is a complicated dynamic process, especially in the aspect of contact response between slab and rock-fall. The application of rock-fall shed is seriously restricted because of the current research status. In view of the present disadvantages of Herzt contact law, a theoretical method of dynamic response of reinforced concrete (RC) slab is proposed based on the numerical indentation test and the Olsson’s model. Compared to the presented methods, the results obtained in this paper are much closer to the results of finite element method. Meanwhile, the impact forces obtained by Herzt model are larger because of without considering of plastic deformation. As a much reasonable method, it can be used to analyze the dynamic response of RC slabs subjected to impact load of rock-fall. At the same time, it also provides an effective numerical analysis method for the application of indentation test to civil engineering.