Author(s)

G. C. Giuliani & M. E. Giuliani

Abstract

The roofing of the Crowne Plaza Hotel hall, located in Caserta (Italy), took into account the constraints given by the structural supports to be laid on the top of four existing buildings. The earthquake expected PGA is 0.25g. In order to avoid the important coupling of different structural parts while taking into account the dynamic behaviour of all them, the solution for correctly supporting the roof was found by seismically isolating the roof from the top of the existing buildings. The structural conceptual design included the construction method to be effected by incremental launching of the space frame with the glass panes already fixed. The results of the analysis, the detailing of the structure and the construction method are illustrated. Keywords: seismic isolation, glazed roof, design, erection. 1 Structural conceptual design The glazed roof features a sub square plan with side dimensions of 58.52 m and 58.42 m; because of architectural requirements, the roof was shaped as a shallow lamella dome with a maximum rise at the crown of 6.45 m; see fig 1. The Owner is Progetto Industrie s.p.a, Caserta, the Architect was Gianmaria Beretta, SABA srl Milano, Italy and the Constructor was MAEG, Treviso, Italy. The expected seismic design displacement of the top of the contour in the existing buildings is around ± 0.30 m and therefore the seismic isolation of the lamella dome was assumed as the conceptual way to overcome the problem of imposing such huge displacements on the superimposed structure. A system of two way sliding bearings on the top of three of the contour buildings isolates the lamella dome from the relevant horizontal displacements, while a stiff connection to the fourth one resists the horizontal actions and the torque created by the inertial forces of the superimposed structure.

Keywords

seismic isolation, glazed roof, design, erection.