深厚欠固结填土层深桩基础施工工艺研究  

Study on Construction Technology of Deep Pile Foundation in Deep and Thick Underconsolidated Backfilled Solum

作　　者：冯永光 张勇 刘欢 Feng Yongguang Zhang Yong Liu Huan(Beijing Branch, China Coal Geological Engineering Corporation, Beijing 100073)

机构地区：[1]中煤地质工程总公司北京分公司,北京100073

出　　处：《中国煤炭地质》2017年第6期63-65,共3页Coal Geology of China

摘　　要：在济南市某重点工程的深桩基施工中,存在着桩的类型较多,人工回填碎石土层深厚,且为欠固结状态,地层中存在大块漂石的问题。综合工程场地情况、施工进度、地层条件等因素,采用上部碎石土层人工挖孔成孔和第四系沉积层、岩石层部分采用旋挖钻机成孔的复合成孔施工工艺进行施工。对孔内存在巨大漂石,采用静态破碎剂进行破碎;采用在孔口设置固定四角架,并悬吊垂直吊坠的方式保证人工挖孔桩身垂直度;为消除欠固结碎石土层对桩的负摩阻力的作用,在碎石土层人工挖孔护壁完成后,在内侧护壁上涂抹无腐蚀性的脱模剂或润滑剂。后期的桩基检测表明,桩身完整性检测的I类桩比例为100%,桩基承载力均满足设计要求。施工工期也由计划的120d缩短为90d,节约了现场施工管理成本,为以后类似工程提供了参考。In a deep pile foundation construction of a key project in the Jinan City, has been existed issues of varied pile types, deep and thick artificial baekfilled detritus solum, and large boulder blocks in strata. After comprehensively studied factors of the project site situation, construction schedule and strata condition etc. have used composite completion construction technology of artificial excavation for upper detritus solum, and rotary drilling rig for Quaternary sedimentary layer and rock stratum. To large boulder blocks can use stat- ic breaking agent to break ; to ensure artificial excavated pile hole verticality, can set a fixed quadripod on hole mouth and hang a verti- cal pandant. To eliminate negative friction from undereonsolidated detritus solum on pile, after the completion of detritus solum artifi- cial excavation, spread non - corrosive mold dope or lubricant on inner wall. Subsequent pile foundation inspection has shown that the proportion of category I of pile body integrity inspection is 100% , thus the pile foundation bearing capacity satisfied design require- ment. Construction period has shortened into 90 days from designed 120 days, thus saved site construction management cost and pro- vided reference for similar project afterwards.

关 键 词：深基础 欠固结土层 桩基础施工 嵌岩桩 

分 类 号：TU473[建筑科学—结构工程]