摘要
上第三系地层是一种微成岩的软岩地层,其作为重力坝坝基存在压缩变形和抗滑稳定问题。针对云南桥街水电站,通过工程地质测绘结合钻探、物探等多种勘探手段,将上第三系地层划分为细粒岩组和粗粒岩组,并根据钻孔波速、现场原位直剪成果、原位载荷成果、室内试验成果对其工程地质特性进行了详细分析研究。研究表明:上第三系地层岩性软弱,其变形模量、抗剪强度及承载力低,抗滑和抗变形能力差,且不同岩组由于颗粒组成的不同其物理力学性质存在明显差异,需进行坝基处理。采用锚筋桩与灌注桩结合固结灌浆的复合地基处理方案,可以有效解决坝基的压缩变形和抗滑稳定问题。桥街水电站工程的成功经验表明:复合地基技术可以运用于水利水电工程的坝基处理,能提高坝基抗滑和抗变形能力。
The upper tertiary stratum is a kind of micro-diagenetic soft rock stratum,as the foundation of gravity dam,there are problems of compressive deformation and anti-sliding stability.Through engineering geological mapping,combined with various exploration methods such as drilling and geophysical exploration,the upper tertiary stratum of Qiaojie Hydropower Station were divided into fine-grained rock group and coarse-grained rock group.According to the borehole wave velocity,in-situ direct shear,in-situ load and laboratory test,the engineering geological characteristics were analyzed in detail.The research showed that the lithology of the upper tertiary stratum was weak,its deformation modulus,shear strength and bearing capacity were low,its anti-sliding and anti-deformation capacity were poor.The physical and mechanical properties of different rock groups were obviously different due to different particle composition,so it was necessary to carry out the dam foundation treatment.We adopted composite foundation treatment scheme of anchor pile and bored pile combined with consolidation grouting,which could effectively solve the problem of dam foundation compression deformation and anti-sliding stability.The successful experience of Qiaojie Hydropower Station project showed that the composite foundation technology could be applied to dam foundation treatment of water conservancy and hydropower projects,which could improve the anti-sliding and anti-deformation capacity of dam foundation.
作者
林红
阮璐
李少飞
LIN Hong;RUAN Lu;LI Shaofei(Yunnan Institute of Water﹠Hydropower Engineering Investigation Design and Research,Kunming 650021,China)
出处
《人民长江》
北大核心
2020年第11期153-160,共8页
Yangtze River
关键词
软岩坝基
坝基处理
复合地基
锚筋桩
灌注桩
桥街水电站
soft rock dam foundation
dam foundation treatment
composite foundation
anchor pile
bored pile
Qiaojie Hydropower station
