【作者】 王璞；

【导师】 黄真；

【作者基本信息】 上海交通大学 ， 结构工程， 2012， 硕士

【摘要】 国内外研究者对钢筋混凝土构件在拉、压、弯、剪、扭单一或者二、三种组合受力作用下的研究已比较深入。但是,对拉/压、弯、剪、扭四种组合受力的共同作用研究还不充分,特别是轴力对于组合受力下钢筋混凝土构件的破坏机理和承载力影响的研究有待深入。目前,国际上缺乏工程界普遍接受的拉/压弯剪扭组合受力钢筋混凝土构件统一破坏计算理论,各国规范多用经验公式,因此这方面的研究有重要的理论意义与实际应用价值。本文通过理论模型推导、试验数据比较和数值模拟分析方法研究轴力对于组合受力下钢筋混凝土构件的破坏机理和承载力影响。首先,本文改进应用三维极限平衡理论,通过研究斜扭破坏面空间角度改变考虑轴力对构件组合受力破坏形式和极限承载力的影响。应用混凝土截面微元的多轴受力破坏准则,确定破坏面几何形状,通过几何形状确定的变角度斜扭破坏面的平衡方程建立钢筋混凝土构件组合受力承载力的统一计算模型表达式,并与试验数据相比较。进一步,本文建立数值分析模型,用相关试验结果校核数值分析模型,应用数值模拟分析方法拓宽研究参数,弥补组合受力钢筋混凝土构件试验数据的不足,并与本文建议的理论模型比较。本文通过探索轴力对于组合受力下钢筋混凝土构件的破坏机理和承载力变化影响,建立钢筋混凝土构件组合受力破坏的承载力统一计算模型,这一计算模型与试验研究数据比较一致,并与数值分析模型的研究结果一致。论文研究成果可为进一步完善混凝土破坏理论和规范相关计算方法提供参考。更多还原

【Abstract】 There are rich research results on reinforced concrete structural members under single loading or two and three loading combination of tension, compression, bending, shear and torsion. However, there are few researches on four loading combination of tension/compression, bending, shear and torsion, especially for the axial force effects on the failure mechanism and bearing capacity of reinforced concrete members. Till now, there is not a unified failure model for reinforced concrete members under combined loading which has been commonly accepted worldwide. Many design codes for combined loading are consisted of test data fitting experience formulas. Therefore it is very important to focus research on the unified failure model of RC members under combined loadings.The dissertation studies failure mechanism and bearing capacity of the RC members under combined loadings through theoretical investigation, test data comparison and numerical analysis method.Firstly, the ultimate equilibrium theory is improved and used to study the influence of axial force to failure mode and ultimate capacity through the variation of the twist failure surface angles. Applying concrete failure criteria on the failure surface, the twist failure surface angles could be determined, and using the three dimensional ultimate equilibrium theory, the unified failure model and formulas for reinforced concrete structural members under the combined loadings could be deduced. The theoretical results are compared with the experimental results and the coordination of both is satisfied.Then, the numerical analysis method is used to broaden the research parameters, which could solve the test data lack problem. More attention is paid on the check of numerical modeling with the existed experimental results and numerical analysis results are compared with theoretical results.The dissertation suggests the unified failure model for reinforced concrete structural members under combined forces of tension, compression, bending, shear and torsion. The theoretical model fits well with the test data and the numerical analysis results. The research results could be used as references for concrete failure theory and design codes.更多还原