【作者】 宗敏；

【导师】 曹朗；

【作者基本信息】 河海大学 ， 结构工程， 2004， 硕士

【摘要】 本文在总结已有大跨度楼板结构形式的基础上，提出了一种新型的大跨度楼板体系——钢筋混凝土双向空腹板，该类楼板体系是现有圆管式空心楼板的延伸，不仅能减轻楼盖自重、增大板跨，而且还具有宏观上双向性的优点。本文通过理论分析和有限元方法相结合，研究了钢筋混凝土双向空腹板在竖向荷载作用下的受力机理和变形特征，并提出了一些设计建议和实用公式。 本文从虚功原理出发，结合有限元方法，给出了双向空腹板的弹性刚度实用计算公式，并与近似刚度公式进行对比分析，并得出结论：在双向空腹板孔间肋较大情况下，利用近似公式计算双向空腹板的弹性刚度偏小，可按本文提出的弹性刚度公式进行计算。 本文根据弹性薄板理论，导出了双向空腹板的平衡微分方程，并通过理论计算和通用有限元程序ANSYS结果对比，验证了其正确性；通过对各类边界条件下双向空腹板挠度和弯矩系数的计算比较，本文提出：双向空腹板跨中挠度及跨中、支座弯矩可使用本文空腹板刚度公式查找现有的实心板挠度弯矩系数表进行计算，完全能满足工程精度要求。 本文利用有限元程序ANSYS，建立了钢筋混凝土双向空腹板的非线性计算模型，并和等跨等厚度实心板进行分析对比，从而得出了一些重要结论，指出：在空腹板自重比实心板减少40％左右后，空腹板的刚度虽然由于截面的开孔而削弱，但考虑自重减少后，空腹板仍表现出整体性好、刚度大的特征，从而实现较大跨度楼板的工程应用。 最后本文利用有限元分析了钢筋混凝土空腹板在开裂后的短期刚度，并给出计算其短期刚度的建议公式；另外针对双向空腹板的特点，本文提出了对这种变截面板进行承载力计算的“等效截面刚度法”模型，并给出了相关的配筋建议及构造措施。更多还原

【Abstract】 On the basis of summarizing the existing large-span slab structure forms, the author developed the existing circular voided slab into a new large-span slab system, RC bi-direction cellular slab, which, specialized itself as bi-direction from a macro point of view, could not only reduce the tare weight of slab, but also expand slab span. With combined effort in theoretical analysis and FEM, the author studied engineering mechanism and distortion character, under vertical load, of RC bi-direction cellular slab, and put forward some ideas on construction design and practical formulations.Starting from virtual work principle, with the combination of FEM, the author led into elastic stiffness practical formulation of bi-direction cellular slab. After comparing the bi-direction elastic stiffness formulation with the approximately stiffness formulation, the author drew such a conclusion that if the hole-rib is comparatively big, the elastic stiffness of bi-direction cellular slab calculated by approximately formulation would be comparatively small, and therefore the elastic stiffness could calculated by the formulation illustrated in this paper.In light of the elastic thin plate theory, the author induced equilibrium differential equation of bi-direction cellular slab, which was proved correct through analysis and comparison to result of ANSYS to with theoretical calculation. Through the deflection and bending moment coefficient calculation of bi-direction cellular slab under various boundary conditions, the author brought forward the theory that the deflection of mid-span and bending moment coefficient calculation of mid-span and support of bi-direction cellular slab could be in accordance with solid plates’, which could satisfy the precision of engineering.The author, applying the program of ANSYS, built a nonlinear model of RC bi-direction cellular slab, and, from the comparison of equivalent-span andequivalent-thickness solid plate, drew several important conclusions. Meanwhile he also pointed out that the stiffness of cellular slab would become weaker because of the holes of cross-section which make the tare weight 40% down comparing to solid plate, but if the weakness of tare weight was considered, the cellular slab still remained the excellent features of integration and stiffness, by which the cellular slab can be put into use of large-span.In the end, the author used FEM to analyze the short-period stiffness after RC cellular slab cracking, and presented recommended formulation in respect of short-period stiffness. Moreover, with regard to the features of bi-direction cellular slab, the author brought forward the equivalent cross-section stiffness model to calculate the ultimate load-carrying capacity of variable cross-section slab as well as the related reinforcement suggestions and conformation methods.更多还原