[关键词]
[摘要]
为研究新型内翻U形外包钢-混凝土组合梁正截面抗弯承载力及其构造要求，以已有内翻U型外包钢-混凝土组合连续试验梁为参照，建立该组合连续梁非线性有限元模型，模拟组合连续梁有限元模型的荷载-跨中挠度曲线，并与相关试验结果对比，验证了该组合梁有限元模型的建模方法和参数选取的合理性和有效性。应用建立的组合连续梁有限元模型，分析了内翻外包钢-混凝土组合梁正截面抗弯承载力的主要影响参数。综合内翻U型外包钢-混凝土组合连续梁正截面抗弯承载力试验和模拟结果，提出采用简化塑性理论计算组合梁正截面抗弯承载力计算时，组合梁正截面抗弯承载力塑性理论计算值应乘0.96的修正系数。0.96倍组合梁正截面抗弯承载力塑性理论计算值与组合梁有限元模型模拟计算值比较表明两者十分偏安全地接近，提出的组合梁正截面抗弯承载力修正的简化塑性理论计算值具有足够的准确性和可靠性。
[Key word]
[Abstract]
In order to study the normal section bending capacity and structural requirements of a new type of inverted U-shaped steel-encased concrete composite beam, nonlinear finite element models of the composite continuous beams have been stablished with the reference of the existing U-shaped steel-encased concrete composite continuous test beams, and the load-mid-span deflection curves of the finite element models of the composite continuous beams have been simulated and compared with the related test results. The rationality and effectiveness of the modeling method and parameter selection of the composite beam finite element models are verified. Based on the finite element model of composite continuous beams, the main influencing parameters of bending capacity of inverted steel-encased concrete composite beams are analyzed. Based on the test and simulation results of normal section bending capacity of inverted U-shaped steel-encased concrete composite continuous beams, a simplified plastic theory is proposed to calculate the normal section bending capacity of composite beam, but the plastic theoretical calculation value of the normal section bending capacity of the composite beam should be multiplied by the modified coefficient of 0.96. The comparison between the plastic theoretical calculation value of the normal section bending capacity of the composite beam and the simulation value of the finite element model of the composite beam shows that the two values are very safe and close, and the modified simplified plastic theory calculation value of the normal section bending capacity of the composite beam is accurate and reliable enough.
[中图分类号]
[基金项目]
国家自然科学基金项目（面上项目，重点项目，重大项目）
