You are encouraged to attend the defence. The details of the defence and attendance information is included below: 

Date: December 06, 2024
Time: 2:00 PM to 4:00 PM (PT)

Defence mode: Remote
Virtual Attendance: via Zoom

LINK TO JOIN: Please contact the Office of Graduate Administration for information regarding remote attendance for online defences.

To ensure the defence proceeds with no interruptions, please mute your audio and video on entry and do not inadvertently share your screen. The meeting will be locked to entry 5 minutes after it begins: please ensure you are on time.

Thesis entitled:  DYNAMIC PERFORMANCE ASSESSMENT OF LIGHTWEIGHT TIMBER-STEEL COMPOSITE PEDESTRIAN BRIDGES

Abstract:  As lightweight, slender footbridge designs gain popularity, pedestrian-induced vibrations are becoming a prominent concern in modern bridge engineering. The reduced mass and stiffness of these structures make them flexible and, hence, more vulnerable to dynamic oscillations, impacting pedestrian comfort and structural serviceability. 

Timber-steel composite bridges, in particular, have recently gained attention as an efficient and eco-friendly solution for footbridges. However, the dynamic behavior of these composite structures under pedestrian and other dynamic loads remains underexplored, as current research has predominantly focused on steel, concrete, and timber-only footbridges. Addressing this gap, the current study investigates the dynamic performance of three timber-steel composite footbridges, providing new insights into their behavior under dynamic loads.

The research scope encompasses a thorough analysis of comfort criteria, focusing on vibration serviceability for pedestrian-induced loads per CSA S7 guidelines. Various pedestrian load models were applied for all critical modes that were identified. Consideration was given to human-structure interaction effects and pedestrian-structure lock-in. Additional evaluations assess bridge responses to wind and seismic forces to give a comprehensive overview of the dynamic performance of composite timber-steel pedestrian bridges. 

Results reveal that timber-steel composite footbridges, while offering favorable load-bearing characteristics, require careful vibration control to meet comfort standards, particularly under pedestrian-induced loading. The study also evaluates the effectiveness of passive control devices, such as Tuned Mass Dampers (TMDs), demonstrating their utility in enhancing the dynamic response of these structures. Such configurations were found to be effective in mitigating vibrations and maintaining desirable comfort levels.

To sum up, this work serves as a means to increase the understanding and knowledge regarding the dynamic performance of timber-steel composite footbridges under various loading conditions and to suggest practical measures to overcome any serviceability issues. 

Defence Committee: 
Chair: Dr. Mauricio Dziedzic, University of Northern British Columbia 
Supervisor: Dr. Asif Iqbal, University of Northern British Columbia 
Committee Member: Dr. Muntasir Billah, University of Calgary 
Committee Member: Dr. Muhammad Tariq Chaudhary, Kuwait University 
External Examiner: Dr. Shahria Alam, University of British Columbia – Okanagan