福建砌石拱坝施工技术与经济分析

福建省的砌石拱坝设计体型日趋多样化 ,并向新颖、轻、高和薄的方向发展 .对石料的强度要求从严 ,形状要求从宽 ;混凝土普遍采用“双掺”技术 .施工机械有国产的 ,也有进口的 .大坝面石砌筑 ,多数采用粗料石丁砌 ,砂浆深勾缝防渗 ;腹石砌筑 ,从卧砌发展为竖砌 ,不求单块自稳 ,石料之间允许点接触 ,层高为 0 .8～ 1.0m ,强调砌体密实性及埋石率 ,大坝每升高 3～ 5m进行一次压水试验检查砌体透水率 ,并进行补强灌浆 ,大大提高了坝体自身的防渗能力 .实践证明 ,随着砌石拱坝施工工艺水平的提高 ,近百米级的高、薄砌石拱坝 ,不设混凝土防渗面板或心墙 ,只靠坝体自身防渗是可行的 ,是一种比较经济的坝型 .

Construction Technology for Masonry Arch Dams in Fujian and Economic Analysis

In recent years, the types of masonry arch dams in Fujian are gradually diversified and optimized, and develop to new, light, high and thin types. In material selection, stones selected are required to be hard and wide, and two admixtures are generally mixed with concrete. In construction machinery selection, conventional machinery is combined with modern machinery. During the placement of dam surfaces, T shaped coarse stones are always adopted and deep stone crevices are filled with cement mortar for seepage control. During the placement of a dam body, the horizontal placement is developed to vertical; the self stability of single blocks is not required, and the point contact is permitted; the height of each masonry layer is 0.8～ 1.0?m , and the compactness and displacer capacity are emphasized during placement; besides, water pressure tests are preformed to examine the perviousness of the dam for every 3～5m rise of the height of the dam, and grouting for dam reinforcement is implemented, greatly increasing the anti seepage capacity of the dam. Practice shows that with the improvement of construction technology, dams, without construction of anti seepage face slabs or core walls, can realize seepage control by themselves, and that such a type of dams is economical.