卵石夹漂石层灌注桩钻孔施工方法的优化

Optimization of Drilling Construction Method for Bored Piles in Pebble-Boulder Layer

近年来,随着我国城市化建设的快速发展,钻孔灌注桩在地下综合管廊、下穿隧道等市政工程围护结构中的应用越来越广泛,与SMW工法桩、地下连续墙等围护结构相比,其具有适用性强、耐久性高、易于施工、造价低廉等特点,已逐渐成为深基坑围护结构的首选。以杭州市临安区苕溪南路下穿隧道围护结构为例,以卵石夹漂石层段灌注桩钻孔施工为主线,对不良地质条件段钻孔灌注桩钻孔设备的选型、工艺优化以及减少灌注桩混凝土超灌等方面进行了详细的介绍,对类似地下工程围护结构施工具有一定的参考及借鉴价值。

As rapid development of urbanization construction recent years in China, the application of bored piles is getting more and more extensive in enclosure structures of underground utility tunnel, undercrossing tunnel and other municipal works. Comparing with SMW pile method, underground continuous wall and other enclosure structures, this method has advantages such as good applicability, high durability, easy for construction and lower costs which made it the first selection for the enclosure structures of deep foundation pit. Taking undercrossing tunnel enclosure structure of Shaoxi South Road in Lin'an District of Hangzhou City as an example, and taking bored pile construction in pebble-boulder layer as mainline, this paper introduces in details of selection of equipment mode for bored pile drilling in adverse geological conditions, technology optimization and reducing concrete overfilling of bored pile which provides certain reference values for similar construction of underground enclosure structure.