Abstract: It is a engineering technological problem internationally for seepage treatment for underwater concrete of hydraulic structures and other else. In this paper the underwater LW chemical material grouting and the construction technique of SR anti-seepage module sticking are introduced for which it is used to treatment the transverse joints upstream at the dam block No. 19~20 in Xin’anjiang hydropower station. In addition, the author in this article discusses the new techniques which combine new anti-seepage underwater material with hydraulic technology in underwater construction．This new technique successfully carried out underwater anti-seepage treatment for transverse joints upstream under water 38.2 m.

摘要： 水工建筑物水下混凝土的渗漏及其他缺陷治理，是一项国际性工程技术难题，本文介绍了在新安江水电站19-20号坝段横缝上游面进行的水下LW化学灌浆和SR防渗模块粘贴施工工艺，探索了水下防渗新材料与水下施工液压技术相结合的水下防渗工法，在国内首次实现了38.2m水深错台横缝迎水面的水下防渗施工。