锚固结构爆破振动规律与损伤的模型试验

 选用水泥砂浆和玻璃钢分别模拟岩石和锚杆，进行物理模型试验，结合理论分析和实践，研究锚固结构不同部位在掏槽爆破作用下的振动规律与损伤，并结合小波包分析，对动应变信号进行深层次的分解分析。结果表明：在爆破作用下，对于邻近工作面的一排锚杆，其锚固段和自由段的振动规律在频率、幅值、持续时间和波形方面明显不同，此排锚杆的振动能量大，但频带较宽，能量分散；随着离工作面距离的增加，锚固段和自由段测点的振动应变波幅值和频带迅速衰减，振动能量集中在窄的频带内，且持续时间有所增长。结合试验结果、现有的理论和实践，分析锚固结构在爆破作用下的振动损伤或失效，基于锚固结构的不同形式的损伤，从控制振动的幅值、主频段、持续时间和提高结构的抗动载性能方面，提出预防锚固结构损伤的建议。

VIBRATION RULE AND DAMAGE OF ANCHORAGE STRUCTURE SUBJECTED TO BLASTING USING MODEL TEST

In this paper，cement mortar and glass fiber reinforced plastics are used in physical model test to simulate the rock and anchor bolt，respectively. Physical model tests are performed according to similarity law of materials. Vibration rule and damage of different sections of anchorage structure are studied under cut-hole blasting in combination of test，theory and practice. The vibration strain signals are implemented by wavelet packets analysis. The results show that：(1) Under the blasting loading，vibration rules of the anchored and free sections(a row of anchor bolts in the vicinity of working face) are different in frequency，amplitude，duration and waveform. Vibration energy of the row of anchor bolts is basically large，but the energy is distributed randomly with a wide frequency band. (2) With increase of the distance from the working face，amplitude and frequency of vibration strain wave decrease rapidly on anchored and free sections. Vibration energy concentrates in narrow frequency band，but with longer duration. Based on different failure patterns，suggestions are proposed to prevent structure from damage by controlling amplitude，main frequency band and duration of vibration. In addition，anti-dynamic performances of structure should be improved.