公路桥梁钻孔灌注桩桩底沉淀层厚度探讨

研究了钻孔灌注桩桩底沉淀层的形成原因，分析了钻孔灌注桩桩底沉淀层的危害。通过某高架桥摩擦桩超声波检测的工程实践发现，在钻孔灌注桩沉淀层厚度满足施工要求时，利用超声波检测桩身完整性却存在问题，表明现行设计、施工与检测规范存在一定脱节。针对钻孔灌注桩施工中的沉淀层厚度控制提出了几点建议，以降低桩底沉淀层带来的工程质量安全隐患。

Thickness of Sediment Layer at Bottom of Highway Bridge Bored Pile

This paper studies the causes of bridge bored pile sediment layer, analyzes the harm of the bored pile sediment layer. Through the engineering practice of ultrasonic inspection of one viaduct friction pile, the paper founds that when the thickness of the bored pile sediment layer meets the requirement of construction, using ultrasonic to inspect the integrity of the pile exists some problems, which shows that there is some disconnect in current design, construction and testing specification. The paper puts forward some suggestions to control the thickness of bored pile sediment layer in construction, in order to reduce the quality and safety hidden danger caused by bored pile bottom sediment layer.