在土石坝工程中,经高强度反复碾压后的筑坝土石料会达到非常密实的状态,从而表现出明显的超固结特性,未考虑这种特性的土石坝应力变形计算分析中,通常会使低坝的变形计算结果偏大,高坝的变形计算结果偏小。通过设定初始屈服面或初始加载函数,本文提出一种可考虑坝料初始超固结特性的土石坝变形计算方法,分别结合沈珠江双曲服面模型和邓肯-张EB模型讨论了具体的实现方案,进行了不同坝高、考虑和不考虑坝料初始超固结特性的算例分析,结果表明,所提出的方法可有效解决土石坝变形“低坝算大,高坝算小”的现象。
In earthrockfill dams, the earth and rockfill materials for dam construction can reach very dense state after highintensity roller compaction, and thus often appear overconsolidated. In conventional stressdeformation analysis of earthrockfill dams, this overconsolidation characteristic is not considered, which often results in larger deformation prediction for low dams while smaller deformation prediction for high dams. Through the setting of an initial yield surface or loading function, this paper presents a stressdeformation analysis method to consider the initial overconsolidation of dam materials. Specific imple mentation schemes for Shenzhujiang's doubleyieldsurface model and DuncanChang EB model are dis cussed respectively. Stressdeformation analyses, with and without considering the initial overconsolidation of dam materials, are performed for earthrockfill dams of different height. The results show that the pro posed method can effectively resolve the "larger result for low dams, smaller result for high dams" problem of deformation calculation for earthrockfill dams.