关键词: 灯泡贯流式机组, 管型座, 混凝土损伤, 超载分析, 非线性有限元,

Abstract: In combination with the engineering practice of a bulb tubular turbine hydropower station in Laos, a finite element model of the ground powerhouse structure including bedrock was established in this paper. Considering the softening and damage characteristics of the concrete, ABAQUS was used to analyze the mechanical characteristics of tubular pedestal concrete of the bulb tubular turbine. The results show that the concrete damage area of the tubular pedestal mainly concentrates on the top and bottom of the flow channel at downstream of the column. Besides, the damage area develops along the hole of the tubular pedestal, and there are penetrating damages between the column hole and turbine access hole. The damage value at the top of the flow channel is larger than that at the bottom, and no apparent damage is found in other parts of the concrete. Moreover, optimizing the reinforcement ratio of tubular pedestal concrete is helpful to better put combined bearing characteristics of reinforced concrete into full play, and the corresponding overload coefficient of concrete of tubular base is 3.42, which is fully satisfactory for the tubular pedestal design.

Key words: bulb tubular turbine unit, tubular pedestal, concrete damage, overloading analysis, nonlinear finite element method,