宜兴抽水蓄能电站上水库主坝堆石料湿陷变形研究

Collapsibility Deformation of Rockfill Materials on the Upper Reservoir's Main Dam of Yixing Pumped Storage Power Station

宜兴抽水蓄能电站上水库主坝采用库盆开挖料填筑,库盆出露的基岩为五通组砂岩夹泥岩和茅山组砂岩夹泥岩,针对这两组岩性具有泥岩含量较高、软化系数偏小的特点进行了混合堆石料湿陷变形研究,分析砂岩夹泥岩堆石料在长期浸水作用下附加沉降对坝体变形的影响。试验成果表明,砂岩夹泥岩堆石料的湿陷系数小于1.5%,该工程堆石料不具有明显的湿陷性;堆石湿陷特性与其饱和抗压强度有密切关系;主坝堆石料的湿陷特性指标处于一般堆石料常见值范围内。在对库盆采取了全面的防渗排水措施后,主坝建成后运行期间堆石不具备发生大范围饱和的可能。研究成果为充分利用库盆开挖料筑坝以降低工程投资提供了科学依据。

Excavated materials are used to fill the main dam of the upper reservoir in the Yixing Pumped Storage Power Station .The exposed bedrock contains Wutong and Maoshan group sandstone mixed with mudstone .According to the characteristics of these two groups of lithology , it studies the collapsible deformation of rockfill materials which contain high content of mudstone and low soften -ing coefficient .It also analyses the effect of dam deformation due to the rockfill materials of additional settlement of the sandstone mixed with mudstone under longtime submerged condition .The experimental results shows that the coefficient of collapsibility of the sandstone mixed with mudstone rockfill materials is less than 1.5%.The rockfill materials of this project don＇t have obvious collaps-ibility and the collapsibility is closely related to their saturated compressive strength .The collapsibility index of the rockfill materials is in a common range .After taking seepage control and drainage system , the rockfill materials does not have the possibility on wide range of saturation during operation of the completed main dam .The research results provide scientific bases for the full utilization of excavated materials from the basin of the reservoir to reduce the engineering investments .