柔性拱和软弱地基上的碾压混凝土拱坝

为改善软弱基础上修建碾压混凝土拱坝的结构设计 ,通过对水压和温度荷载作用下坝体的应力和位移分析 ,提出了适应软弱基础拱坝变位大但应力不恶化的“柔性拱”及简易止裂措施 ,已用于修建新疆石门子碾压混凝土拱坝。坝体设人工短缝加大拱的变位 ,可消减水压和温度作用下的拉应力集中 ;扩大拱座降低坝肩软弱岩面上的压应力和剪应力 ,拱座考虑侧约束减少拱座在水压作用下的变位 ,也增加坝肩绕渗途径

Flexible RCC arch dam on a weak foundation

Analyses of the stresses and displacements due to the hydraulic pressure and thermal load were used to improve the structural design of a roller compacted concrete (RCC) arch dam on a weak foundation. A flexible arch with simple anti crack measures was added to accomodate the large deformations of an arch dam on a weak foundation without increasing the stresses. These measures were used to construct the Shimenzi RCC arch dam in Xinjiang Uygur Autonomous Region. The artificial short joints in the dam body increase the arch deformation but reduce the tensile stress concentrations due to the under hydraulic pressure and the thermal load. The enlarged arch abutment reduces the compression and shear stress of the abutment and increases the seepage distance around the abutments due to the hydraulic pressure. The deformation of the arch abutments is reduced by the lateral restraint of the abutment.