Garage for California University

Abstract

California University has constructed a two storey garage, with a prestressed concrete structure, at Berkeley. A particular feature of this building is that on the roof a soil layer, 0.45 cm in depth, has been laid, on which there is a grass lawn. The structure consists of a framework of beams, of 7.30 m span, in one direction, and 19 m in the other: this being the maximum separation of the columns in one elevation. Consequently the flooring is made of slabs spanning the shorter 7.30 m distance. The roof slab has been prestressed in two mutually perpendicular directions, hence it is practically impossible for it to develop cracks. This arrangement renders the slab watertight and implies a saving in the cost of applying waterproofing treatment. As the building is surrounded on three sides by three contention walls, advantage has been taken of this to transmit to these the horizontal thrusts due to windage and seismic forces. Most of the structural elements, excepting the flooring, have been prestressed and prefabricated at a workshop 80 Km. away from the site. Many of the constructional units have additional reinforcement, which can be post-tensioned after erection at the working site.