实腹式型钢混凝土梁正截面承载力下限

Lower Limit of Strength of Full Web SRC Beams

实腹式型钢混凝土梁中型钢和混凝土之间的滑移会引起梁正截面承载力的变化,本文阐述了取得这一变化下限的条件和计算此下限值的方法。这一方法为评估粘结退化的型钢混凝土梁的承载力提供了科学的依据。首先,从梁中型钢和钢筋混凝土之间有滑移时的协调变形问题出发,提出复合平截面假定,讨论了取得梁正截面承载力下限的条件,建立了求解此下限值的截面平衡方程组,并将其数值解与试验结果进行对比,发现二者符合比较好,并给出相应的简化计算方法用于工程设计实践。

While Slip between steel shape and reinforced concrete in full web steel reinforced concrete（SRC） beams gives cause for change of strength of the beams, this paper elucidates the conditions of the lower limit of this change and the method by which values of the lower limit are calculated. It can be used to evaluate the strength of SRC beams after bond-slip. First, compatible deformations of steel shape and reinforced concrete in SRC beams are examined and composite Bernoulli＇s principle is proposed. The conditions of the lower limit of strength of full web SRC beams are discussed and section equilibrium equations for the lower limit are built and the numerical answers give satisfactory predictions as compared to the test results. Finally, a simplified method is put forth for the practical design.