“钢筋混凝土迭合构件”一文中的B_(d2)计算公式(10),物理概念明确,推导过程清晰,按B_(d2)验算迭合梁第二阶段挠度,其计算值与实测值符合良好。但从刚度和挠度的计算来看,还比较繁琐,拟作简化。当M_1=0,h_(01)-h_o时,迭合梁即为整体梁,但B_(d2)却不能表达整体梁的刚度,故式(10)与整体梁刚度公式不能衔接,同时也缺少迭合梁总刚度的表达式。试验结果表明,迭合梁在第二阶段M_1+M_2的共同作用下,当迭合前M_1较小时,其垂直裂缝的再出现及发展状况与整体梁相当,即使是迭合前M_1较大的迭合梁,从第二阶段受力至破坏的过程 The B_(d2) formula (10) in the article “Reinforcement of reinforced concrete elements” (10). The physical concept is clear and the derivation process is clear. The second stage deflection of laminated beams is calculated according to B_(d2), and the calculated and measured values ​​are calculated. In line with good. However, from the calculation of stiffness and deflection, it is still relatively tedious and is intended to be simplified. When M_1=0 and h_(01)-h_o, the laminated beam is the whole beam, but B_(d2) cannot express the stiffness of the whole beam. Therefore, formula (10) cannot be connected with the integral beam stiffness formula, and it is also missing. The expression of the total stiffness of the laminated beams. The experimental results show that under the combined effect of the second stage M_1+M_2, when the superposed M_1 is smaller, the reappearance and development of vertical cracks is comparable to that of the whole beam, even if M_1 is large before superposition. Stacked beams, from the second stage to the destruction process