钢筋混凝土梁受弯承载力简化计算

SIMPLIFIED CALCULATION ON BENDING CAPACITY OF REINFORCED CONCRETE BEAMS

从混凝土受弯构件的基本假定和基本公式出发,推导出采用内力臂系数进行受弯承载力计算的简化公式。经过大量计算,分析了弯矩、配筋率和混凝土强度对内力臂系数的影响。最后,基于在我国混凝土梁纵向受拉钢筋配筋率基本不大于1.6%的情况,建议采用简化公式进行梁配筋设计时。内力臂系数可取0.80(C30混凝土,HRB 40钢筋)或0.85(C35混凝土,HRB 400钢筋)。

In this paper,the simplified formulas of the flexural capacity are deduced by means of internal lever arm coefficient,based on the basic assumptions and equilibrium equations of reinforced concrete bending members.The influence of moment,the reinforcement ratio,the strength of the concrete is analyzed.Finally,the suggestions of suitable internal lever arm coefficient are put on condition that the reinforcement ratio of concrete beam is not greater than 1.6% in China,when calculating of reinforcement and the flexural capacities of concrete beams.Internal lever arm coefficient suggested is 0.80 （C30 concrete,HRB 400 steel reinforcement）or 0.85 （C35 concrete, HRB 400 steel reinforcement）.