深厚软质岩土石混合料地基桩基负摩阻力现场试验及数值模拟研究  

Experimental and numerical study on pile negative friction in deep and thick backfill ground consisted of soft rock and soil

作　　者：张晓健 艾传井 龚辉 章涵[3] Zhang Xiaojian;Ai Chuanjing;Gong Hui;Zhang Han(Central Southern China Electricity Power Design Institute,Wuhan 430071,China;Guizhou Bridge Construction Group Co.Ltd.,Guizhou 550000,China;China University of Geosciences (Wuhan),Wuhan 430074,China)

机构地区：[1]中国电力工程顾问集团中南电力设计院有限公司,武汉430071 [2]贵州桥梁建设集团有限责任公司,贵州550000 [3]中国地质大学(武汉),武汉430074

出　　处：《工程勘察》2019年第1期24-29,40,共7页Geotechnical Investigation & Surveying

摘　　要：受用地制约,现有大部分电力工程建设都在山区,场地平整后存在深厚的填土,且成份多以土石混填为主,组成极不均匀。位于此类地基中的桩基后期会产生较大负摩阻力,对桩基承载力影响较大。本文对土石混合填方区中的桩基负摩阻力展开了现场试验研究,得出负摩阻力的大小、中性点位置以及随时间的变化规律,并且与抗拔试验进行对比分析,提出了确定负摩阻力合理科学的计算方法。同时通过数值模拟,得出不同压实度,不同桩径及不同填土厚度对桩侧负摩阻力时效演变规律的影响,为更好地进行桩基设计提供基础。The electric power projects are always constructed in mountain area subjected to land use. The construction site is filled deeply and thickly with the inhomogeneous mixture of rock and soil in the site formation. Negative friction will exist in the piles constructed in this kind of ground and affects the pile capacity greatly. The in-situ pile negative skin friction test is carried out to study the negative friction value, neutral point and the evolvement rule with time. Compared the results with the pile pulling test, a scientific and reasonable method to calculate the negative friction is recommended. Meanwhile the influence of the compactness, pile diameter and the fill thickness on pile negative skin friction with time is studied by numerical simulation. The conclusion could be used for pile design.

关 键 词：深厚填土 负摩阻力 中性点 压实度 数值模拟 

分 类 号：TU473.1[建筑科学—结构工程]