水电站坝下游面钢衬钢筋混凝土管道损伤和承载特性

基于混凝土塑性损伤模型,对某水电站坝下游面钢衬钢筋混凝土管道的损伤和承载特性进行了非线性有限元分析.结果表明:在正常运行工况下,裂缝主要出现在位于坝体之外的背管部分,数条贯穿性裂缝将由主变平台延伸至上弯段;主变平台附近管道受力状态复杂,管道断面出现贯通性损伤,可能出现短小而密集的裂缝;温度变化对结构受力影响明显,特别是温降荷载将引起管道外侧损伤区进一步发展,靠近管壁外侧的钢筋拉应力明显上升,因此应注意管道表面的保温和防护.

Damage and Bearing Characteristics of Steel Lined Reinforced Concrete Penstock on Downstream Face of Dam in Hydropower Station

Based on the concrete plastic-damage model, the damage and bearing characteristics of steel lined reinforced concrete penstock laid on the downstream face of dam in a hydropower station were analyzed by nonlinear finite element method. The results indicate that cracks mainly appear in the penstock outside the dam body, which extend from the main transformer platform to the upper bending section. The stress state of the penstock near the main transformer platform is complicated, and the damage zones are connected, so short cracks may appear densely in this part. In addition, the penstock is obviously affected by temperature change, and temperature drop will lead to the extended damage zone on the lateral side of the pipe wall and the increased tensile stresses of reinforcement. Therefore, more attention should be paid to the surface insulation and protection of the penstock.