混凝土倒“T”形叠合板承载力的计算方法

Calculating method for bearing load capacity of RC invertible "T" slab-composite slab

提出一种只发生"部分叠合"的新型混凝土倒"T"形叠合板结构形式.采用肋部厚度已达最终设计厚度的倒"T"形截面预制板,使之能直接承受后浇叠合层混凝土的自重和施工活荷载,节省模板和临时支撑;再根据倒"T"形叠合板的构造特点和试验研究及实际工程应用,提出了这种新型叠合板以倒"T"形板为跨中弯矩的承载主体,后浇叠合层混凝土仅参与正常使用阶段工作的基本假定,建立了计算内容与整浇梁板相同的、简单可靠的承载力计算方法.由于计算过程中将仅发生部分叠合的后浇叠合层混凝土的实际结构功能予以降低,故设计者可根据实际工程情况赋予倒"T"形预制板凹槽内的后浇叠合层混凝土某些附加的有益功能,如保温、防渗、轻质等,从而进一步提高该结构的安全性和适用性,更有利于这种新型叠合板结构的推广应用.

A new kind of the invertible 'T' precast slab construction style with part composition is put forward. It adopts the design thought that its rib thickness has reached the final design thickness. It can sustain directly the weight of the later cast concrete and the moving loads of construction, saving the supports and formworks. Based on the construction characters and engineering application of the invertible T slab, the new kind of composite slab is put forward, the invertible T slab being the major part to bear the middle bend. The later cast concrete of composite part just satisfies the basic hypothesis in the normal use period. Compared with the whole casting slab's calculation contents, the load calculation way is simple and reliable. Because the construction functions of the later casting concrete is weakened, designer can attach additional functions to the later casting concrete of the invertible T slab according to the engineering's conditions, such as heatpreservation, permeationprevention and light weigh. This can further improve the safety and application of this structure, which makes it popularized and applied easily.