论文部分内容阅读
在框架设计中,框架梁根据受力需要或构造要求,一般在梁的上、下边都需要布置钢筋。但是,在进行框架梁的正截面强度计算时,常忽略受压钢筋的作用,按单筋截面设计。这种方法计算简单,能满足结构的安全要求,可采用手算和电算。但这种方法有一个明显的缺点,就是增加钢筋用量。经理论分析证明,在多数情况下,按单筋截面设计会导致框架梁一些截面钢筋用量增加10%左右,当弯矩比较大,构件截面尺寸又比较小时,钢筋用量的增加超过20%。由于增加了框架梁的钢筋,特别是增加了框架结点上部的钢筋,不仅造成材料的浪费,也增加了施工的难度。另一方面,根据结构的非线性分析可知,由于增加了框架梁的钢筋,当结构承受的荷截达到或超过极限荷载时,可能
In the frame design, the frame beams need to be arranged on the upper and lower sides of the beams according to the force requirements or the construction requirements. However, in the calculation of the normal section strength of the frame beam, the effect of the pressed steel bar is often ignored and the single-bar section design is adopted. This method is simple in calculation and can meet the safety requirements of the structure. Hand calculations and computer calculations can be used. However, this method has a significant drawback, that is, increase the amount of rebar. Theoretical analysis shows that, in most cases, the design of a single-bar section will result in an increase of about 10% in the amount of reinforcement in some sections of the frame beam. When the bending moment is relatively large and the section size of the components is small, the amount of reinforcement used increases by more than 20%. As the reinforcement of the frame beam is increased, in particular, the reinforcement at the upper part of the frame node is added, not only the material waste but also the construction difficulty is increased. On the other hand, according to the nonlinear analysis of the structure, it can be seen that due to the increase of the steel reinforcement of the frame beam, when the load intercepted by the structure reaches or exceeds the ultimate load, it may be