【摘要】 介绍一新的钢筋混凝土双筋梁的计算方法和算例,该法是在单筋梁的计算公式基础上推导而得。受压区混凝土压应力分布仍然采用矩形加抛物线。计算公式形式与单筋梁的相同,简洁明了。在计算钢筋面积时,无须将弯矩分解成两部分,即混凝土受压合力与对应的钢筋拉力组成的力偶矩和受压钢筋与对应的受拉钢筋组成的另一个力偶矩。受拉钢筋总面积可直接求得。在事先制成的计算表格中已自动排除了超筋,即无须验算受压区的最大高度,受拉和受压钢筋的应变均能大于其屈服应变。更多还原

【Abstract】 A new method for calculation of doubly reinforced concrete beams and some related examples are introduced. The calculation based on the same stress distribution in compression zone is derived from the method of computing singly reinforced beams. The calculation formulas are simple and similar to those of the singly reinforced concrete beams. It is not necessary to divide bending moment into two parts: one related to concrete compression force and another to compressive reinforcement. The total amount of tensile reinforcement can be directly determined. The case of over reinforced section can not occur, if the calculation is done with the design tables prepared in this paper. A check of the maximal height of compression zone is not necessary. The strains of tensile and compressive steel bars are both larger than their elastic limits.更多还原