高薄碾压混凝土拱坝设计创新与实践

碾压混凝土拱坝具有施工快、材料省、开挖小等优点，是适合高山峡谷地区的优秀坝型。但由于采用薄层碾压施工，层间强度低于本体、层面渗流问题突出，具有显著的各向异性的特性；且高碾压混凝土拱坝在一个枯水期难以浇筑完成，汛期需要临时成拱挡水度汛；碾压层面渗流问题较突出，坝体排水要求高。上述这些设计、施工难点成为制约该坝型进一步发展、推广的关键因素，需要有所突破。针对高薄碾压混凝土拱坝上述技术特点，依托三里坪、云龙河两座高薄碾压混凝土拱坝，研究提出了“强拱弱梁”的设计理论和方法、“下诱上横”组合式分缝、坝体立体网格排水系统等一系列创新技术。上述新技术已成功应用于工程实践，推动了碾压混凝土坝的技术进步，可供同行参考借鉴。

Design innovation and practice of high and thin arch dams of roller compacted concrete

Roller compacted concrete (RCC) arch dams have advantages of fast construction, low material consumption and small excavation, which is an excellent dam type for high mountainous and gorge areas. However, due to the thin layer rolling construction, the interlayer strength of RCC is lower than that of the bulk concrete, which has significant anisotropic characteristics. As the dam is hard to construct to required elevation in one dry season, the dam needs to form an arch shape temporarily to resist flood in flood season. And owning to seepage of rolling interlayers, the drainage solution in dam body is demanding. According to above technical features and difficulties of the RCC arch dam, and based on Sanliping and Yunlonghe dams, we put forward some innovation design concepts such as strong arch and weak beam dam design theory, geometric design method and control standard, new combined joint of lower inducing joint and upper transverse joint, three-dimensional grid drainage system. The research results have been successfully applied to engineering practices, promoted the progress of the construction technology of RCC high-thin arch dams, and can provide references for other dam construction.