上海市建筑科学研究院5号综合楼加层设计是一项技术难度较高的设计项目,原建筑为3层框架结构,柱网为6.6m×7.5m、顶层为15m跨度的大空间食堂,屋面梁采用YGW—15—10先张预应力拱式屋架,屋面为1.5m×6.6m钢筋混凝土大型屋面板。为达到加层改建中不影响食堂的正常使用,且保持周围环境整齐文明和不破坏绿化的要求,通过多种方案比较,最后大 The design of the fifth floor of the Shanghai Academy of Building Research is a technically difficult design project. The original building is a three-story frame structure with a column net of 6.6m by 7.5m and a large-scale space canteen with a top floor of 15m. The roof beam adopts YGW-15-10 pretensioned prestressed arch truss and the roof is a 1.5m×6.6m reinforced concrete large roofing board. In order to meet the requirements of normal use of the canteens and to maintain the neat and civilized surroundings and not to afforest green areas in the retrofitting, a variety