水电站垫层蜗壳配筋计算

为研究“Г”形框架简化、平面简化和接触摩擦对垫层蜗壳配筋计算的影响，分别采用结构力学法和有限元法对某垫层蜗壳进行计算结构力学法对蜗壳进口断面进行等截面简化，将其作为深受弯构件进行配筋计算；有限元计算采用ABAQUS软件，建立完整标；住机组段蜗壳结构模型及蜗壳进口断面平面轴对称模型，在铜蜗壳和混凝土及垫层之间创建接触对，模拟接触摩擦关系，将计算得到的弹性应力图形作为配筋依据计算结果表明，采用平面“Г”形框架法可能造成计算配筋面积偏小；在考虑接触摩擦的前提下，将蜗壳结构简化为轴对称结构进行初步配筋计算是可行的；对垫层蜗壳结构进行有限元分析时有必要考虑接触摩擦，摩擦系数f应慎重取值.

Reinforcement Calculation for Spiral Case Embedded with Cushion Layer of Hydropower Station

Both structural mechanics and finite element method （FEM）were used to calculate a spiral case embedded with cushion layer in order to study the influencing factors of the reinforcement calculation for it. The influencing factors include Г-frame simplification ,plane simplification and contact friction between spiral case and concrete. When structural mechanics was used,the intake cross-section was simplified as a uniform frame,which was considered as a deep flexural member in reinforcement calculation. The FEM analysis was carried out by using the software ABAQUS. A standard unit block model and a axisymmetric model of the inlet section of spiral case structure were established. In addition,the intake cross-section was modeled by using plane axisymmetric element. Contact pair was created between spiral case and concrete,also between spiral case and cushion layer. The calculated elastic stress diagram is the foundation of reinforcement. It is concluded that the Г-frame simplification may cause the smaller calculated reinforcement area than needed. It is feasible to simplify spiral case structure as plane axisymmetric model in preliminary reinforcement calculation on condition that the contact friction is considered. It is necessary to take the contact friction into consideration in FEM calculation for spiral case embedded with cushion layer,and the friction factor should be defined cautiously.