直坑道内防护门上的爆炸冲击波荷载

Shock wave loads on the blast door in straight tunnel

为可靠开展抗爆结构设计与评估,基于理论计算与数值分析对直坑道内爆炸冲击波荷载的计算问题进行了研究。定量对比分析了现有不同方法计算结果的差异,基于结构响应对不同方法进行了评价,并结合模型实验对近距离爆炸情况下直坑道内防护门上的设计荷载取值问题进行了研究。结果表明,在进行荷载简化时有必要考虑荷载形式与结构响应的耦合,而现有坑道内爆炸冲击波荷载的简化计算方法普遍没有考虑结构动态特性影响,且相互之间存在很大差异,严重影响设计或评估工作的可靠性;近距离爆炸情况下,取门中线上距门边1/4宽度处的压力或门上平均压力作为坑道内防护门上的设计荷载,在比较宽的结构频率范围内是合理的。研究结果可为坑道内结构的防护设计提供参考。

In order to improve the design and safety assessment of the reliability of blast-resistant structures,we studied the simplified calculation of the shock wave loads caused by HE explosions in straight tunnel based on the theoretical calculation and numerical simulation. Firstly,the differences among existing calculation methods of in-tunnel shock wave loads and their results were evaluated quantitatively in detail and the effects of such differences on structure responses were discussed. Then the design loads on the blast door in a tunnel was studied based on the model test and numerical analysis. The results show that it is important to take into account the coupling effects of the structure response when developing simplified calculation methods for intunnel explosion shock wave loads. The existing simplified methods generally disregard such effects and differ from one another significantly,which leads to much more uncertainty in both design and assessment. For close range explosion,the design loads on the door can be taken from pressure at the point on the midline and 1/4 door-width away from the door-side,or from the average pressure on the door,which is reasonably acceptable in a wide range of structure frequencies. The present work can provide a reliable method for protection design of in-tunnel structures.