【作者】 张明；

【导师】 沈蒲生； 张友亮；

【作者基本信息】 湖南大学 ， 建筑与土木工程， 2005， 硕士

【摘要】 超长现浇混凝土空心楼盖是集超长混凝土结构与空心楼盖于一体的楼盖形式，兼具二者的结构特性。在结构设计与工程应用中，应分别考虑超长混凝土结构与空心楼盖的技术特点。 超长混凝土结构突出的问题就是在非荷载作用下有可能开裂。通过对各种非荷载应力进行了计算分析。得出引起超长混凝土楼盖开裂的主要因素有：气候变化引起的温度应力、混凝土的收缩应力和水化温升引起的温度应力。 对构造配筋、设置后浇带和使用微膨胀混凝土等控制裂缝的有效措施进行了讨论。分析楼板受相邻梁柱约束程度的变化规律，可知构造配筋的作用效果可以直接按照两端受固支约束的构件进行讨论，讨论结果表明通过构造配筋可以提高楼板的抗开裂能力和有效控制楼板开裂之后的裂缝宽度发展，并提出了混凝土应力应变与配筋率、合理的配筋率、裂缝宽度与配筋率之间的关系、裂缝宽度与裂缝数量之间的定量关系等，可以作为设计控制的理论依据。此外指出设置后浇带宜短些，否则失去作用。讨论了微膨胀混凝土控制裂缝的机理。 现浇混凝土空心楼盖是在实心楼盖中按照一定数量的高强薄壁筒心，以得到较轻的结构自重和较大的承载力，使结构能跨越更大的空间。本文选择由三角级数和多项式组成的挠度函数，在满足正交各向异性板的基本微分方程和边界条件的基础上，推导了正交各向异性板的一般解。即用弹性理论建立受力模型，分析楼盖内部的弯矩分布，探讨了影响楼盖内力分布的主要因素。 本文将超长现浇空心混凝土楼盖理论应用于实际工程——长沙通程商业广场，采用通用有限元程序ANSYS对结构进行温度应力分析，结构设计中进行了合理选型，合理布置，并采取了诸多有效的措施，使结构受力性能良好，取得了巨大的社会价值与经济价值。并对现浇混凝土空心楼盖的设计方法、构造措施及施工工艺提出了一些建议。更多还原

【Abstract】 Super-long cast-in-site reinforced concrete hollow floors have the characteristics of super-long cast-in-site reinforced concrete structures and hollow floors. Therefore, the both technical characteristics should be taken into account during structural design and engineering application.The non-load crack is the key problem of super-long cast-in-site reinforced concrete structures. Through the various non-load deformations of concrete floor and the corresponding stresses fully be studied, the main factors that induce to crack are as follows: the cracking stress mainly induced by the change of temperature, the shrinkage of concrete and the residual stress caused by hydrate temperature.Reinforcing concrete wall, grooving a stress-release slot in super-long cast-in-site reinforced concrete floor and adopting tiny expansive concrete are good measures to control the cracking. Analyzing the beam-column constraint coefficient along the length shows that the efficient of reinforcement can be discussed by analyzing the fully constrained reinforced members. So based on this conclusion, the relationship of concrete strain and stress to the steel ratio, the relationship of crack width to steel ratio, quantitative relationship of crack width to crack number and the rational steel ratio are discussed in this paper. Furthermore, the results prove that setting stress-release slot is an effective measure if the length of reinforcement concrete basement slab-wall is limited in reason. Finally, how to control cracking by controlling the temperature of tiny extended concrete is discussed.Case-in-site reinforced concrete hollow floor is a new type floor, which is widely used in practice in recent years. High strength thin-wall hollow were placed in the floor by a certain rule, which could get lower deadweight and higher carrying capacity at the same time and enable the floor span more space. The flexural function is selected, which consists of the trigonometric series and polynomial expression. The flexural function satisfies the governing differentiable equation of orthotropic plate and boundary conditions. Therefore the general solution of orthotropic rectangular plate is obtained. Through elastic theory, a calculation model is made to analyze mechanic behavior and the distribution of inner moment of the cast-in-site reinforced concrete hollow floor.The methods of super-long cast-in-site reinforced concrete hollow floors are applied to practical engineering such as Changsha Tongcheng Commercial Plaza. Temperature stresses are analyzed by universal finite element program of ANSYS. The reasonable structural model and disposal and other various availability measures are be taken into account during the structural design, therefore, large social and economic values are obtained. Some reasonable advices about the design method and construction rules about the case-in-site reinforced concrete hollow floor have been put forward .更多还原