韩继云  曲京辉  万墨林  孙梦兰  翟传明
    （中国建筑科学研究院结构所  北京 100013）

[提要]  介绍闭合托架技术在建筑结构改造中的应用实例，闭合托架利用了原有基础，不需增设新的柱基础。托架梁为钢骨混凝土和预应力混凝土与原砖墙组成的组合梁，利用预应力技术可起到加固与卸荷合二为一的作用，使后加结构主动参与受力，改变了原有结构应力过大、后加部分应力滞后的现象。
[关键词]  托换改造  闭合托架  组合梁  预应力卸荷

 An application example of closed bracket to demolish bearing wall is introduced, which uses the old base. The supporting beam is a composite beam that is composed by steel framed reinforced concrete, prestressed concrete and existing brick wall. The prestress technique can help strengthening and unloading work together, and let the new structure bear load actively, and change the phenomenon that the stress of old structure is too much and the partial stress of the new structure lags.
Keywords:  supporting beams; closed bracket; composite beam; prestress; unload