大面积预应力混凝土框架结构合理配筋的探讨

STUDY ON REASONABLE REINFORCEMENT IN LARGE AREA PRESTRESSED CONCRETE FRAME STRUCTURES

大面积预应力混凝土框架结构设计时一般将直接荷载产生的作用与温度、混凝土收缩产生的作用分开计算,分别配筋以满足裂缝控制的要求,这种做法不尽合理。确定预应力筋和非预应力筋用量时,应将框架梁按照拉弯(压弯)构件需求进行配筋。为解决超长预应力混凝土框架中间跨预应力损失较大的问题,可采取在中间跨增配预应力筋、利用后浇带或施工缝将预应力筋分区段张拉等措施。在次梁与板中为有效利用无粘结预应力筋,建议在板厚许可的情况下尽量采用曲线形预应力筋。

Effect of load and indirect load such as shrinkage, creep was often taken into account separately to satisfy the requirement of crack width in reinforcement design of large area prestressed concrete frame structures. It is less than reasonable. Frame beams should be reinforced as members subjected to flexure and axial force. Some effective measures were presented to solve bigger prestress loss of mid span in overlong frame and it is suggested that prestressed reinforcement with curve linetype should be adopted in slabs if possible.