基于结构模态的纵向采空区群爆破动力响应

摘要 构建纵向采空区群离散多自由度动力响应模型，提出基于结构模态的空区群爆破动力响应分析方法.针对某金矿工程实例，对该方法进行检验分析.结果表明:该方法计算结果可直观反映采空区群内部岩体的位移与速度响应规律，揭示岩体爆破动力响应特性，与数值模拟结果趋于一致；受内部阻尼作用，岩体作减幅振动，振幅逐渐衰减至0；在爆破荷载施加位置，岩体响应强度最大，随着与爆破作用点之间距离增大，响应强度呈减弱趋势.结构模态分析方法可大幅缩短计算时间、提高计算效率，为岩体的动力响应研究提供了一种新方法.
Abstract：Discrete multi-freedom-degree dynamic response model of vertical gob group was developed. Based on structural modal， a new method analyzing gob group blasting response was presented. In combination with a typical engineering problem， verification and discussion were made for the method. Results indicate that the method can directly reflect gob group rock mass response law of displacement and velocity， and describe its blasting response characteristics. The results are in accordance with that of numerical simulation. For internal damping， rock mass vibration damping， the amplitude decays to zero gradually. Rock mass where the blasting loads act on has the strongest response strength. With an increase in the distance between rock mass and the blasting position， response strength of rock mass weakens. The method can greatly decrease computation time and increase calculation efficiency and it provides a new direction for dynamic response analysis of rock mass.