特高混凝土面板堆石坝的结构分区研究

Structural zoning type of rockfill dam with super-high concrete panel

面板堆石坝变形控制的前提是保证坝体各分区的施工质量,而这与坝体分区结构设计关系密切。在坝体分区结构设计环节中,差异过大的主次堆石分区会导致面板出现过大的挠度变形,同时也容易产生开裂、脱空等问题。通过三维非线性有限元分析计算,着重从结构设计理论的角度分析了特高面板堆石坝应力变形特性的影响因素。结合某特高混凝土面板堆石坝,设计了坝体的不同分区方案,从计算结果的对比分析中得出了特高坝的建议分区原则:若次堆石区填料材料特性较差,应尽可能保证次堆石区靠近下游,同时主堆石区和次堆石区分界线应靠近下游;尽量避免次堆石区设置在坝顶范围,以免在次堆石区产生较大的竖向位移对坝顶及上游坝面的影响;全断面采用主堆石区或减小主次堆石区变形模量的差异性,有利于坝体的变形协调。

The premise of deformation control of rockfill dam with concrete panel is to ensure the construction quality of dam subareas,which is closely related to their structural design.During the structural design of dam subareas,the large difference between the primary and secondary rockfill zoning will lead to excessive deflection and deformation of the face slab,and it is also easy to cause problems such as cracking and void.Through three-dimensional nonlinear finite element analysis and calculation,the influencing factors of stress and deformation characteristics of super-high face rockfill dam are analyzed from the perspective of structural design theory.Starting with the structural zoning of dam,combining with the rockfill dam with super-high concrete panel,and referring to the partitional structure of the cross section of the built super-high dam body,different zoning schemes of the dam body are designed,and the recommended zoning principles of the super-high dam are obtained from the comparative analysis of the calculation results:(a)if the filling material characteristics of the secondary rockfill area are poor,the secondary rockfill area should be ensured to be close to the downstream as far as possible,and the boundary between the main rockfill area and the secondary rockfill area should be close to the downstream;(b)it is advisable to avoid setting the secondary rockfill area near the dam crest as far as possible,so as to avoid large vertical displacement in the secondary rockfill area;(c)adopting the main rockfill area in the whole section or reducing the difference of deformation modulus between the primary and secondary rockfill areas is beneficial to the deformation coordination of the dam.