摘要
针对安徽省南部丘陵山地存在的上覆砂质粘土、土层以下为风化岩层的输电线路工程地质条件,提出了环保型直柱锚杆复合基础。通过10组基础的现场施工与原位试验,得到了不同加载工况下基础的荷载位移曲线,分析了直柱锚杆复合基础的承载机理、设计方法与关键设计参数取值。研究结果可为直柱锚杆复合基础的设计与施工提供参考。复合基础施工宜采用"先直柱开挖、后岩体植筋"的作业流程。立柱嵌岩深度对复合基础的上拔承载力与水平承载力影响显著,复合基础上拔承载力计算中的上部立柱部分极限强度发挥系数取0.55~0.6,下部岩石锚杆部分极限强度发挥系数取1.0。复合基础的施工工艺可靠、承载性能良好,可在丘陵山区输电线路工程中试点应用。
Focusing on the transmission line geological conditions for the highly weathered rock with a thin surface of clay covered in southern mountain area of Anhui Province, a newly column anchor composited foundation with environmental protection has been proposed. Based on 10 foundation field prototype tests, the change rules of the composited foundation including the load-displacement curves, the mechanical performance, the design method and the calculation parameters are obtained. The results could provide theoretical basis for the design and implement of column anchor composited foundation. The construction of the column anchor composited foundation should adopt the construction procedure with the excavated column firstly and anchoring secondly. The embedded length of upright column has significant influence to the uplift bearing capacity and horizontal bearing capacity of column anchor composited foundation. The key design parameters of the composited foundation for the uplift bearing capacity calculation are summarized. The upper upright column efficiency coefficient is from 0.55 to 0.6, and the lower rock anchor efficiency coefficient is about 1.0. The practical application in the transmission line verifies the feasibility of the newly composite foundation.
作者
魏峰先
郑卫锋
Wei Fengxian;Zheng Weifeng(CIGIS（CHINA）LIMITED,Beifing 100007,China;China Electric Power Research Institute,Beijing 100192,China)
出处
《工程勘察》
2018年第10期20-24,共5页
Geotechnical Investigation & Surveying
基金
国家电网公司科技项目(GC17201600230)
关键词
输电线路
复合基础
直柱基础
岩石锚杆基础
承载力发挥系数
transmission line
composite foundation
upright column foundation
rock anchorfoundation
efficiency coefficient of bearing capacity
