Application of Karhunen2Loeve Expansion in Stochastic Analysis of Seepage Field L I Shao2long1 , YANG J in2zhong2 , ZHANG J ia2fa1 (1. Key Laboratory of GeotechnicalMechanics and Engineering of the M inistry ofW ater Resources, Yangtze R iver Scientific Research Institute, W uhan　430010, China; 2. National Key Laboratory of W ater Resources and Hydropower Engineering Sciences, W uhan University, W