溪柄碾压混凝土薄拱坝坝体渗漏处理

Dealing with leakage of Xibing roller compacted concrete thin arch dam

介绍溪柄大坝蓄水后出现的严重渗漏情况,分析渗漏原因,重点阐述防止渗漏所采取的措施.通过比较,选择从坝顶竖直向下钻孔、垂直于层间缝面的交缝灌浆形式对层间缺陷进行堵漏防渗兼补强灌浆.进行了灌浆施工设计,根据既要防渗堵漏又要补强的灌浆目的提出了特殊的施工要求:灌注低浓度浆液的时间适当放长,确保小孔隙得到较好灌注;不许采用间歇式灌浆方法提高灌浆效率;对单孔灌浆时间和注浆总量不设上限控制.灌浆后对大坝进行查勘,原先的渗出点不再出现渗水,表明施工效果良好.

In allusion to the serious leakage occurring in the Xibing dam body after water impoundment, the causes of leakage were analyzed, with emphasis on the measures for seepage control adopted for treatment of inter-layer defects, such as boring from the top toward the bottom of the dam body and placement of grout holes perpendicular to the joint face. In consideration of the objectives of the project, special requirements of construction were put forward, including prolonging low-concentration grouting to ensure the sufficient grouting in small pores, avoiding the adoption of batch-type grouting to improve the grouting efficiency, and without setting the upper limit of the time and total amount of grout filling in single holes. The survey of the dam after grouting shows that there is no leakage from the original seepage points, demonstrating the good effect of construction.