多维爆破地震动作用下框架结构动态响应有限元时程分析

爆破震动的幅值、频率与持续时间是结构爆破震动响应与破坏的重要参数，爆破安全规程规定地面建筑物的爆破震动判据采用质点峰值震动速度和主震频率，但没有指明是三向速度的合速度还是单向速度，给爆破震动判据应用带来不便。文中采用有限元时程分析讨论了不同爆破震动频率速度荷载作用下结构的动态响应，指出在较高频率的爆破震动荷载作用下，框架结构对竖直向地震波响应较大，易在竖直向地震波作用下产生破坏，并可以将三维爆破震动中最大震动速度幅值作为爆破震动安全标准值；在较低频率的爆破地震荷载作用下，震动的水平荷载引起结构的破坏是主要的，应考虑水平最大荷载的爆破震动安全标准值。即结构抗震的安全标准在高频时以垂直荷载速度峰值为准；在低频时以水平荷载速度峰值为准。

Finite-element time-history analysis of dynamic response of frame structure under multi-dimensional blasting vibration

The amplitude, frequency and duration of blasting vibration are the important parameters causing blasting vibration response and breaking of structure .Safety Regulations of Blasting stipulates that the criterion of structure blasting vibration are the peak vibration speed of particles and the main vibration frequency, but it doesn’t point out that the speed is total speed of three directions or one direction speed, which makes trouble to apply the blasting vibration criterion. In the paper, the structural dynamic responses under different blasting vibration frequency-speed loads are discussed by the finite-element time-history analysis, and pointed out that the frame-structural response to vertical blasting vibration is greater under higher frequency blasting loads, which means the structure will get broken much easier under vertical blasting vibration. So the maximum speed amplitude among the three-dimensional blasting vibration can be used as the safety standard of blasting vibration. While structural damage caused by the horizontal blasting load is primary under the blasting vibration loads of lower frequency. So the maximum horizontal load should be used as the blasting vibration safety standard. Namely the vertical speed amplitude under high-frequency loads or the horizontal speed amplitude under low-frequency loads structural can be used as vibration-resistant safety standard.