施工阶段自承重楼盖体系设计中若干问题

Problems in design of self-supporting floor system during construction

为促进套建增层结构的发展,提出施工阶段自承重混凝土楼盖体系,利用钢结构自身可承重的特点,在施工阶段用钢桁架主梁以及钢箱次梁组成钢结构楼盖体系承担施工荷载,在使用阶段钢结构内置于混凝土内形成组合楼盖体系承担新增荷载,这种楼盖体系在套建增层改造工程中具有结构受力和施工措施一体化的优点.结合绥芬河清云市场套(扩)建改造工程实例,介绍了施工阶段自承重混凝土楼盖体系的设计思想,对楼盖体系中预应力内置钢桁架混凝土组合梁的设计进行了较为详细的阐述,对外套框架柱的选取以及梁柱节点锚固长度、主次梁连接构造等问题也作简要介绍.

In order to promote the development of outer - jacketing structure, a self - supporting floor system during construction was proposed, in which the steel structure can carry load by itself. During the construction, the steel floor system formed by steel - truss primary beam and steel - box secondary beam carries the construction load, and during the service, the steel structure is encased in concrete to form the composite floor system to cant the new loads. This kind of composite has the merit of combining load - carrying capacity and construction measures together in outer -jacketing structures for adding stories. Combining with the recon- struction （extension） project of Suifenhe Qingyun Market, the design idea of concrete floor construction system is introduced and the method of prestressed encased steel truss concrete composite beam design is expatiated. Selection of frame column, embedded length of beam column connection and bond construction between primary beam and secondary beam are briefly introduced.