基于单弹簧联结单元法的白鹤滩拱坝孔口配筋非线性有限元分析

采用单弹簧联结单元法及混凝土四参数损伤模型,对施工期工况下白鹤滩拱坝的6~#底孔结构进行了钢筋混凝土三维非线性有限元计算,分析了配筋对孔口结构应力状态的影响,以及配筋后混凝土的损伤情况、钢筋应力分布及裂缝开展宽度等。结果表明,加入钢筋对该孔口大部分区域的混凝土应力影响不大,但会使大梁、下游闸墩等拉应力较大部位的应力状态有所改善;该孔口中仅在大梁与闸墩结合处发生轻微损伤,加入钢筋能在一定程度上限制损伤的增大和扩展;6~#底孔中钢筋应力不大,裂缝开展宽度满足规范要求。

Single-spring joint element method-based nonlinear finite element analysis on orifice reinforcement of Baihetan Arch Dam

With the single-spring joint element method and four-parameter damage model for concrete，a 3-D reinforced concrete nonlinear finite element calculation is made on the structure of the No.6 bottom outlet of Baihetan Arch Dam under construction for analyzing the effect from the reinforcement on the stress status of the orifice structure，the damaging status of the concrete after reinforcing，the stress distribution of the reinforcement，the cracking width，etc. The result shows that there is no larger effect from the reinforcement on the stress of the concrete within most of the regions of that orifice，however，the stress statuses of the locations of the girder，downstream gate pier，etc. with larger tensile stress are improved somewhat. Within the orifice，only slight damage occurs at the joint between both the girder and the gate pier，for which the increase and extension of the damage can be restricted to a certain extent by reinforcing，while the stress of the reinforcement in the No.6 bottom outlet is not so large and the cracking extension width can meet the requirement of the criteria concerned as well.