Multistory Prefabricated Columns

Concrete slabs in lift-slab buildings are cast one on top of the other, separated only by bond-breaking agents. After hardening of the top slab taken place, the slabs are lifted to their corresponding levels by means of high-strength steel bars pulled by hydraulic jacks placed on top of the columns. Conventional practice in North America has been to attain the total height of the building with a series of two-or-three-story column tiers. The paper described the advantages of reducing the number of column tiers and erection cycles to a minimum. The design and construction of multistory buildings at the University of Havana are fully described as examples of this technique. Of particular interest is the description of the design analysis and erection of a nine-story prefabricated reinforced concrete column. The necessary bracing to increase the elastic stability of multistory columns, and the negative effect of their own weight on buckling load are analyzed. Attention is given to the connection detailed between floor system and prefabricated columns in the university buildings.