基于小波包技术的爆破地震效应计算模型及安全判据研究  

Computational model and safety criterion of blasting vibration effect based on wavelet packet techniques

作　　者：陈士海[1] 魏海霞[1,2] 张安康[1] 茅晓辉[1] 

机构地区：[1]山东科技大学土木建筑学院,山东青岛266510 [2]河南理工大学土木工程学院,河南焦作454003

出　　处：《爆炸与冲击》2010年第4期377-382,共6页Explosion and Shock Waves

基　　金：国家自然科学基金项目(50778107);教育部高校博士学科点专项基金项目(20060424002);山东省泰山学者建设工程专项项目~~

摘　　要：采用小波包分解和重构的方法,将复杂的实测爆破地震波速度信号转化为多个简谐波的叠加,将爆破速度荷载作用下结构的动态响应问题转化为一系列简谐荷载作用下的动态响应问题。通过提出速度因子的新概念并反映在爆破地震效应计算模型中,考虑了结构动态响应中瞬态响应的影响。同时爆破地震效应计算模型中又融入了归一化的能量比例,在考虑爆破荷载频率的影响时仅需考虑占有相当能量比例的优势频率的综合作用。然后,在该计算模型基础上提出了一个新的爆破地震效应安全判据。该判据能反映出爆破激励荷载作用下结构速度响应大小与结构特性、爆破荷载幅值、频率(包括多个优势频率)、持续时间及能量比例等参数的关系。最后结合实际工程案例,通过使用基于小波包技术的爆破地震效应计算模型与时程分析法,分别求解出速度响应幅值并将结果进行对比,验证了所建模型的可行性。Complex measured velocity signals of blasting vibration are transformed into the superposition of several simple harmonic waves by the wavelet packet decomposition and reconstruction techniques. In this way, the problem of structural dynamic response under the action of blasting velocity load becomes the problem of that under a series of simple harmonic loads. By introducing a new concept of velocity factor into the computational model of blasting vibration effect, the contribution of structural transient response is considered into structural dynamic response. At the meantime, normalized energy proportion is added to the computational model, and only dominant frequencies of relatively large energy proportions can be included when considering the influence of blasting load frequencies. Then, on the basis of the model above,a new safety criterion of blasting vibration effect is put forward, which can reflect the relation between the structural velocity response magnitude under blasting load stimulation and the following parameters： structural characteristics, amplitude, frequencies including several dominant frequencies, duration and energy proportion of blasting load. In the end, by combining with an actual engineering case, velocity response amplitudes are calculated by the computational model put forward in this paper and the temporal analysis method, respectively. And the computational results show that this computational model is feasible.

关 键 词：爆炸力学 安全判据 小波包 地震波 速度因子 

分 类 号：O383.2[理学—流体力学] TU311.3[理学—力学]