Analyse dynamique d'un bâtiment de grande hauteur à Montréal par mesures des vibrations ambiantes et modélisation numérique

Abstract

This thesis presents a dynamic analysis, both experimental and numerical, of a tall building located in downtown Montreal. The objective is to quantify the in-situ modal properties, including damping, and to assess the relevance of the cracked concrete stiffness reduction factors used in numerical models of flexible high-rise buildings, as the current CSA A23.3 and NBCC 2020 provisions remain poorly suited to such structures. Based on ambient vibration testing (AVT) covering all 58 floors and conducted using TROMINO® sensors installed throughout the structure, modal parameters (frequencies, damping ratios, and mode shapes) were extracted using the Enhanced Frequency Domain Decomposition (EFDD) and Stochastic Subspace Identification (SSI) methods. These experimental data were then compared with the results of a finite element model (FEM) developed in ETABS, which was calibrated using a global sensitivity analysis and an incremental updating procedure. The study highlights significant discrepancies between code-based assumptions and the in-situ measurements, justifying the adjustment of these parameters in dynamic analyses. This research represents the first study of its kind in Montreal on an instrumented high-rise of this scale. It enhances the reliability of design-stage numerical models by quantifying in-situ damping and mode shapes, typically difficult to assess for such structures, and by evaluating the stiffness gap between the numerical model and the measured structural response.

Date	18 Jan 2026
Original language	French
Awarding Institution	École de technologie supérieure
Supervisor	Rola Assi (Supervisor) & Ahmad Abo El Ezz (Co-supervisor)