冲击钻孔对场地周边建筑物的影响

THE IMPACT DRILLING EFFECT ON THE SURROUNDING BUILDINGS

通过对河南某场地进行冲击钻孔施工时产生的振动进行的现场测试,以评价其对周边建筑的影响。主要测试项目包括:地表加速度、深部土层加速度及土层的分层沉降。分析不同数目钻机同时施工时引起的振动在土层中的衰减规律以及波的传播规律、振动导致的建筑物周边地层的沉降,并提出保障建筑物安全的工程措施。研究表明:冲击钻孔时,地基会产生较大的振动,这种振动在地表和地层内部衰减较快;冲击振动产生的振动波主要以面波和剪切波两种途径传播;在周边建筑地表粉土层,振动的频率相对较低。采取隔孔打桩,并控制同时施工数量的方法能有效降低振动对周边建筑物的影响。

The vibration of impact drilling was tested to evaluate the impact on surrounding buildings. The main test items included： acceleration on ground surface, acceleration in deep layers, and soil layer deposition. The vibration attenuation rules, wave propagation rules and deposition near the building in different formations caused by vibration were analyzed, and the engineering measures were taken to ensure the building safety. The result showed that the vibration would be generated in foundation obviously during impacting drilling. And the rate of vibration attenuation was higher on ground surface and in the inner formation. The waves caused by vibration propagate in two ways. Vibration amplitude was mainly distributed in relatively lower frequency range in the silt layer near the ground surface. Using method of every hole piling and limiting the number of drilling could reduce the impact of vibration on surround buildings effectively.