面板堆石坝面板开裂机理与防止措施研究

Study on the crack mechanism of face slab of concrete face rockfill dam and its prevention measures

针对面板堆石坝面板在施工过程及蓄水时的实际受力变形特点,对面板的开裂机理进行了深入探讨。通过分析发现,混凝土干缩和温度应力是造成面板早期细小裂缝产生的主要因素,而坝体变形所造成的对面板的剪切挤压力、面板的自重以及施工期反向水压力则是造成面板后期呈规律性开裂的主要因素。为改善面板的受力条件,提高面板的防渗能力,同时方便施工,从材料、结构和施工三个方面提出了防止措施的建议。

In accordance with the actual stresses and deformation characteristics of face slabs of concrete face rockfill dam during construction period and impoundment period, this paper deeply discusses the crack mechanism of face slab. The analysis shows the drying shrinkage of concrete and temperature stresses are main factors of causing the early fine cracks of face slabs, and the shear crushing forces on face slab caused by the deformation of dam body, the dead-weight of face slab and the inverted water pressure during construction period are main factors of causing late cracks of face slab. In order to improve the stress conditions of face slab and increase its impervious capacity, this paper puts forward some crack prevention measures from the aspects of materials, structures and construction.