第38卷第6期 2016年12月
土木建筑与环境工程
Journal of Civil,Architectural &. Environmental Engineering
doi:10.11835/j.issn.1674-4764.2016. 06.003
基础尺寸对碎石土地基扩底基础上拨承
载力影响的现场试验研究翟强，童瑞铭，刘生奎，鲁先龙
（1中国电力科学研究院，北京102401；2甘肃省电力设计院，兰州730050）
Vol. 38 No. 6 Dec.2016
口口
摘要：影响基础上拔承载能力的因素包括地基土物理力学参数及基础尺寸参数，而确定混凝土方量最小、基础上拔承载力最大的基础参数配比是基础优化设计的关键。以戈壁滩碎石土地基中的原状土扩底基础为研究对象，采用正交设计方法，以立柱直径、深宽比、扩展角为影响因素，以基础上拨承载力为分析指标，设计出9组尺寸的足尺基础。通过现场试验，获得了各试验基础的荷载一位移曲线和上拔承载力值，提出了采用渐变率的概念表征荷载一位移曲线的非线性变化特征，通过分析发现基础荷载一位移曲线渐变率与承载能力呈负相关。结合正交试验分析结果，得出立柱直径、深宽比、扩展角3个因素中对碎石土地基原状土扩底基础抗拔承载能力的影响程度由大到小依次为深宽比、立柱直径、扩展角，表明在戈壁滩碎石土地基基础的工程设计中增加深宽比能提高基础抗承载能力。
关键词：碎石土；原状土；输电线路；扩底基础；上拨承载力中图分类号：TU475文献标志码：A
文章编号：1674-4764(2016)06-0017-07
Experimental analysis of the influence of foundation sizeparameters on the uplift bearing capacity of the spread foundation in gravel soil
CuiQiang'，TongRuimin'，Liu Shengkui"，LuXianlong(1. China Electric Power Research Institute, Beijing 100192, P. R. China : 2.Gansu Electric Power Design Institute, Lanzhou 730050, P. R. China)
Abstract:The uplift bearing capacity of the spread foundation is determined by not only soil physical and mechanical characteristics but also its geometry shapes and scales. The foundation size parameters to determine the minimum quantity of concrete, and the maximum uplift bearing capacity, are key to optimize the foundation design. In order to study their effect on the uplift bearing capacity of the foundation, the undisturbed soil spread foundation in Gobi gravel soil is took as the case, Nine full size test foundations are designed, which use orthogonal test method selected column diameter, the extension angle of the foundation foot and the depth-to-width ratio as influencing factors and the uplift bearing capacity of the foundation as examining goal. The in-site static load tests are carried out in the Gobi gravel soil located northwest China. Load-displacement curves of nine test foundations are obtained and the uplift bearing capacity corresponding are concluded. An index named gradual change ratio is proposed to expressing
收稿日期：2016-04-01
基金项目：国家电网公司科技项目（GCB17201400162）
作者简介：崔强（1980-），男.博士，高级工程师，主要从事输电线路岩土工程试验检测研究，（E-mail>everjsl@126.com Received:2016-04-01
Foundation item:State Grid Corporation Science and Technology Project(No. GCB17201400162)
Authogbrisf:gi Qiang (1984- ), PhD, senior engineer, main research interest: test detection on geotechnical engineering 方芳数据transmissionlineproject，（E-maiD)everis@126.com