基于本构关系计算受弯混凝土梁正截面承载力

Calculation of head-on cross-section bearing capacity of concrete beams based on constitutive relation

采用双模量弹性理论研究受弯混凝土梁正截面承载力的计算。基于混凝土受压应力与应变本构关系,由截面静力平衡条件推导直接利用本构关系计算受弯混凝土梁正截面承载力的公式和相应的计算方法,通过算例所得正截面承载力结果与相关规范值进行对比分析。研究结果表明:所推导方法可行且可靠,具有明确的物理意义。

The head-on cross-section of bearing capacity of concrete beams is often calculated by adopting equivalent rectangular graphic method in domestic and foreign criterion; while the characteristic parameters of this method should be determined by a large number of experiments. Bi-modulous theory of elasticity was adopted to calculate the head-on cross-section bearing capacity of concrete beams. On the basis of the concrete stress-strain and constitutive relation, a formula and its calculating method of directly using constitutive relation to calculate the head-on cross-section bearing capacity of concrete beams was deduced by means of static equilibrium conditions of section. The results obtained by examples and relevant standards were compared and analyzed. The results indicate that the method is quite practical and more reliable, and it has a definitely physical meaning.