隐伏活动正断层地区地下建筑的避让问题:以渭河断裂咸阳段为例

活断层对城市建设的影响长期以来受到科研人员与城市建设者的重视。活断层避让距离的确定直接影响活动断裂地区建筑物的选址。伴随着中国地下空间开发进入快速发展阶段，活动断裂地区的地下建筑选址问题应运而生。以隐伏活动正断层为例，综合考虑地下建筑震害影响、隐伏活动正断层地区地质背景、断裂活动性以及发震破坏特征，对活断层地区地下建筑的避让问题开展研究。研究表明：地下建筑受活断层发震的影响比地面建筑小，但断裂发震的影响依然需要重视；隐伏正断层破坏范围受多方面的影响因素控制，地下建筑避让距离的划定需以断层变形带的边界为起点进行；结合渭河断裂咸阳段的地质背景与断裂活动特点，确定断层上、下盘的避让距离分别为30 m和15 m，得出渭河断裂咸阳段地下30 m以浅限建带的宽度为140 m。

Avoidance of underground construction in regions of buried active normal faults:taking the Xianyang segment of the Weihe fault as an example

The influence of active faults on urban construction has long been emphasized by researchers and urban builders, such that the determination of avoidance distance directly affects the selection of building locations in regions of buried active normal faults. With the rapid development of underground space in China, the challenges of underground building selection have emerged. In view of the situation and taking buried active normal faults as an example, we analyzed the influence of earthquake damage in underground buildings, the geological background, fracture activity, and the characteristics of earthquake damage in active fault regions. We then determined the setback distance of underground buildings in these regions. We concluded as follows: Firstly, the impact of seismicity of underground buildings from active faults is smaller than that of the ground construction, but the impact of earthquakes should still be considered carefully. Secondly, the failure range of buried normal faults is influenced by many factors, and the delimitation of the avoidance distance of underground structures should be based on the boundary of the fault deformation zone. Lastly, based on the geological background and fracture activity characteristics of the Weihe fault in the Xianyang Region, the setback distances of the upper and lower walls are 30 and 15 m, respectively. Therefore, the limited construction belt is 140 m wide within 30 m depth.