新疆高混凝土面板堆石坝筑坝填筑标准及变形控制

根据近30年来新疆100 m级以上面板坝建设经验,对坝体填筑标准进行了总结,并结合沉降监测资料,分析了坝高和筑坝材料、施工填筑控制标准、碾压施工参数和运行年限等因素对高面板坝变形控制的影响:(1)对于新疆100～150 m级面板坝,从变形控制的角度看,采用砂砾石填筑的沉降率比采用堆石填筑小0.2%左右,采用砂砾石填筑优于采用堆石填筑;(2)对高震区150 m级以上的高面板砂砾石坝,设计填筑相对密度从不小于0.85提高到0.90必要且可行,且应采用现场原级配大型相对密度试验代替室内相对密度试验方法来确定坝体的填筑标准;(3)提高施工振动碾吨位是减小坝体变形的有效方法,采用目前广泛使用的26 t振动碾,铺料厚度80 cm,碾压8遍,一般能满足150 m级以下面板坝的设计填筑标准要求;对更高的坝建议采用更大吨位的振动碾施工。

Design filling index and deformation control of high concrete faced rockfill dam in Xinjiang Uygur Autonomous Region

Based on the construction practice of concrete faced rockfill dam (CFRD) of 100m level and above in Xinjiang Uygur Autonomous Region in recent 30 years, the design filling index of dam body is summarized. Combined with the settlement monitoring data,the influence of dam height,dam building mate-rials, construction filling control standard, rolling construction parameters and operation life on deformation control of high CFRD is analyzed emphatically in this paper. (1) For 100-150 m level CFRD in Xinji-ang, the settlement rate of the dam body filled with sand gravel is about 0.2% lower than that filled with rockfill, and the dam filled with sand gravel is better than that filled with rockfill from the perspective of deformation control. (2) It is necessary and feasible to increase the design filling relative density from no less than 0.85 to 0.90 for the high concrete face gravel dam with a height of 150 m in the high seismic re-gion. It is very important for dam deformation control to determine the filling standard by replacing the in-door relative density test with the field original large-scale relative density test. (3)It is of great signifi-cance to improve the tonnage of construction vibrating roller to control the deformation of CFRD. The con-struction parameters of 26 t vibrating roller with a thickness of 80 cm and 8 times of rolling generally meet the requirements of the design-filling standard. For high CFRD of 150 m level or above,it is suggest-ed to adopt a larger tonnage-vibrating roller for construction.