高面膜堆石坝发展的需求与关键技术——高面膜堆石坝关键技术(一)

面膜堆石坝是指上游坝面用土工膜防渗的堆石坝。综述了面膜堆石坝半个世纪以来的发展状况,分析了该坝型的特点及该坝型技术在我国的使用现状与需求:面膜防渗结构具有渗透性低微、差异变形适应性强、施工简捷、工期短、造价低等特点;由于国外专利保护等原因,面膜堆石坝技术未能如面板堆石坝和碾压混凝土坝那样广泛交流与推广,自国外第一座面膜堆石坝建成以来,国内尚未建成一座高面膜堆石坝,而我国水电清洁能源的需求、许多深覆盖层坝址与黏土防渗体取土受到环境生态制约的状况,需要高面膜堆石坝发挥其作用,相应的设计分析技术需要较系统深入的研究梳理和集成。概述了该坝型关键技术研究的初步成果,包括高面膜堆石坝的周边夹具效应与设计方法、面膜双向拉伸分析方法、数值精细模拟方法、非散粒体面膜垫层技术、膜顶胀损缺性状量化分析方法。

Need and key technology on development of high membrane faced rockfill dam:key technology of high membrane faced bockfill dam(I)

In this paper,the characteristics and the development status of rockfill dam with surface impermeable geomembrane (i.e., membrane faced rockfill dam,MFRD) during half a century is summed up and.the technology status and constructing requirement on MFRD in China is analyzed. The overall advantage of MFRD is that it is impermeable, suitable to differential deformation, brief to construct and cheap. Due to overseas protection of patents, unlike the concrete faced rockfill dam and the roller compacted concrete dam, the technology of MFRD lacks of wide dissemination and application. Since the first MFRD was built elsewhere, no high MFRD has ever been constructed in China. For the demand of clean energy of hydropower and conditions of ecological environment, MFRD is required to play an important role, and corresponding technology of design and analysis on MFRD demand further studies as well as a systematic and deeper integration. Recent preliminary studies on the result of key technology of MFRD are summarized, which include mechanism of anchoring influence at perimeter of MFRD and eliminating approach, biaxial tensile mechanical property of geomembrane used as surface barrier of high rockfill dam, analysis of stress and deformation characteristics of geomembrane surface barrier for rockfill dam, experimental research on engineering property of non-granular cushion for geomembrane surface barrier of high rockfill dam, and probabilistic analysis of geomembrane puncture on rockfill dam surface.