Evaluation of floor accelerations and spectra in linear and nonlinear regular RC frame buildings

Abstract

This project aims to investigate the influence of building ductility on nonstructural components (NSCs) acceleration demands. It targets also to evaluate simplified methods available in the literature as well as the equation proposed in the recent report NIST.GCR.18.917.43 to compute the NSCs acceleration demands in inelastic buildings. For this purpose, a typical 6-story frame building is designed according to 2015 edition of National Building Code of Canada (NBC) for four cases: 1) moderately ductile frame in Montreal, 2) conventional frame in Montreal, 3) ductile frame in Vancouver, and 4) conventional frame in Vancouver. Montreal and Vancouver were chosen to represent the seismicity in east and west of Canada, respectively. The aforementioned structures were subjected to twelve and seventeen artificial records with 2 and 10% per 50 year probability in Montreal and Vancouver, respectively. The selected and scaled records are compatible with the Uniform Hazard Spectra specified in the 2015 edition of the NBC. The seismic acceleration demands of NSCs in terms of height factor (Ax), component amplification factor (Ar), and floor response spectra (FRS) are generated by performing linear and nonlinear dynamic analysis, and applying the simplified method of Kothari et al. (2017), using SAP2000® software. The obtained factors Ax and Ar are compared to the ones proposed by NBC 2015 and the report NIST.GCR.18.917.43. The results showed that the frame ductility tends to reduce the NSCs acceleration demands and this benefit is less in the conventional construction frames as compared to the ductile and moderately ductile frames. Also, it was found that the seismic acceleration demands of NSCs are higher in Vancouver than in Montreal. The FRS generated by the simplified method are in a good agreement in terms of the shape with the ones obtained from the nonlinear dynamic analysis, but underestimate the ordinates of the FRS. Finally, the PFA/PGA demand suggested by the NBC 2015 is conservative for the inelastic building while the value of Ar is underestimated. The demands suggested by NIST.GCR.18.917.43 fit the required demands better than NBC 2015.

Date	15 Jul 2020
Original language	American English
Awarding Institution	École de technologie supérieure
Supervisor	Rola Assi (Supervisor)