高混凝土坝蜗壳及软垫层互馈机理探究  

Analysis of Mutual-Feed Mechanism of Volute and Cushion in High Concrete Dam

作　　者：姚远 YAO Yuan(Zhongnan Engineering Corporation Limited,Power China,Changsha 410014,China)

机构地区：[1]中国电建集团中南勘测设计研究院有限公司

出　　处：《人民黄河》2019年第9期155-159,164,共6页Yellow River

摘　　要：垫层作为蜗壳与混凝土之间的传力部分,其材料特性和尺寸对发电机组的稳定运行起着重要作用。为探究垫层蜗壳组合埋入方式对结构特性的影响范围及程度,分析比较了不同垫层材料的物理特性,对软垫层物理尺寸进行了特性分析,在对高压聚乙烯闭孔泡沫板软垫层特性进行详细分析的基础上,对蜗壳与垫层之间的摩擦系数、垫层平面铺设范围进行了研究,最后确定了合适的混凝土重力坝蜗壳垫层。同时详细阐述了蜗壳有限元模型的建立过程,通过选取不同的垫层弹性模量,对正常工况、半数磁极短路、短路三种组合甩负荷工况下的蜗壳进行三维有限元计算,进而分析了蜗壳外混凝土的应力分布规律。结果表明垫层弹性模量对蜗壳外混凝土的应力分布影响显著,弹性模量越大外围混凝土越容易出现应力集中,并导致局部裂缝的出现,而采用软垫层则可以很好地避免此问题。The cushion layer acts as a force transmission part between the volute and the concrete,and its material properties and dimensions play an important role in the stable operation of the generator set.In order to explore the influence range and influence degree of the structural characteristics of the buried volute combination,this paper analyzed and compared the physical properties of different cushion materials and analyzed the physical dimensions of the cushion layer.Based on the detailed analysis of the characteristics of the high?pressure polyethylene closed?cell foam board(PE)cushion layer,the friction coefficient between the volute and the cushion and the plane laying range of the cush?ion were studied.Finally,a suitable concrete gravity dam volute cushion was determined.At the same time,the establishment process of the finite element model of the volute was expounded in detail.By selecting different cushion elastic modulus,the three?dimensional finite ele?ment calculation of the volute under three conditions of normal working conditions,half magnetic pole short circuit and short circuit was car?ried out.Furthermore,the stress distribution law of concrete outside the volute was analyzed.

关 键 词：高混凝土坝 蜗壳 垫层材料 有限元分析 

分 类 号：TV734[水利工程—水利水电工程]