丰宁抽水蓄能电站拦沙坝坝基振冲碎石桩加固技术

丰宁抽水蓄能电站拦沙坝坝基为淤泥质粉土地基,土体力学性质较差,土质不均匀,且存在液化问题,地基承载力仅为80kPa,作为拦沙坝坝基不能满足大坝稳定性、承载力及抗震等要求。为此设计采用振冲碎石桩处理坝基,以改善坝基的工程特性。本文详细介绍了工程试桩阶段、施工阶段存在问题以及施工工艺和质量控制方法。工后检测结果表明,按照该施工工艺和质量控制方法,有效保证了工程质量,提高了施工功效,解决了坝基承载力不足、高压缩性、易液化的问题,可作为同类工程参考。

Vibroflotation gravel pile reinforcement technology for retaining dam foundation of Fengning pumped storage power station

The sediment storage dam of Fengning pumped storage power station is built on silt soil foundation which has poor mechanical properties of uneven soil quality and liquefaction. Thus the bearing capacity of the foundation is only 80kPa. It cannot meet the requirements of the stability, the bearing capacity and the seismic resistance of the sediment storage dam. To solve above problems, vibro-replacement stone column is utilized to reinforce the foundation. Based on the filed practice, the engineering problems are described in the process of the construction of the vibro-replacement stone columns, and the corresponding quality control measures and managerial experience are proposed. The post-construction test shows that the presented quality control methods can effectively improve the construction quality and efficiency, and solve the problems of lack of bearing capacity, high compressibility and easy liquefaction of the foundation. It can be beneficial for the similar engineering project.