粉细砂层中桩基缩径处理施工技术

Construction technique of shrinking-path treatment for pile foundation in powder-fine sand layer

结合宁(南京)淮(淮安)高速公路K149+380中桥桩基的施工实例,阐述了在桩基产生缩径后,采用冲击钻重新成孔,抛片、卵石及优质黏土护壁,成功处理桩基缩径现象的施工工艺,指出该工艺确保了成桩质量,值得推广。

Combined with the construction case of pile foundation for middle bridge K149＋380 from Ning-Huai highway,the paper adopts the driller to reform holes.Meanwhile,it also utilizes cast-slice,pebble and sticky soil with high quality to protect wall after the pile foundation cause a shrinking-path.Through the paper＇s elaboration,these construction techniques successfully handle phenomenon of pile foundation＇s shrinking-path.At last,it also points out that this technique ensures pile-formed quality and will be worth spreading.