Structural Health Monitoring of Tall Buildings Using Vibration-Based Techniques

Structural Health Monitoring of Tall Buildings Using Vibration-Based TechniquesSafe & Sustainable Infrastructure

ABOUT THE PROJECT

This project will develop new models for monitoring the structural health of tall and mid-rise buildings.

NOTABLE ACHIEVEMENTS (November 2016)

• Three tests on structures have occurred: one a cantilever beam, two, an existing 8-storey full-scale building frame at the Central Building Research institute, and third a test comprising a 3-storey lab-scale frame was completed at Concordia University.

PROJECT UPDATE (April 2016)

Experimental tests were conducted at CSIR-CBRI India and Concordia on a cantilever beam, a set of multi-storey frame structures to produce appropriate data for developing and validating the proposed innovative methods for system identification and damage detection. For modal characteristics, these tests were subjected to mass and stiffness variation. To identify the most fitted vibration-based technique, numerical models were developed to replicate these experimental tests. The modal curvature approach using wavelet analysis was improved as a result of model calibration against experimental test results. In parallel, existing buildings were identified for in-situ modal investigation. In the first step, the dynamic properties of the selected structures are obtained numerically and optical sensor locations are determined.

RESEARCH ABSTRACT

Building structures are exposed to different types of loading during its service life, which might no have been considered in design or during construction process. These effects may be attributed to exposure to aggressive environment, overloading, excessive vibration, fatigue, etc. which in turn may lead to damage of structural elements. As a result, significant changes in structure performance may occur or even members’ failure conducting to partial or global building collapse. Hence, assessment of damage and its repair process estimated in terms of recovery duration and costs are becoming increasingly important in order to determine the margin safety and serviceability of buildings.

Although Structural Health Monitoring (SHM) systems with wired networks of high performance sensors (e.g. finer optic sensors) are found to be very robust, they are usually very expensive and difficult to implement as compared to wireless sensor networks. Recently, there is a trend in the building industry to use wireless sensor networks in place of wired systems to avoid the high costs and disturbances in normal operation due to the run over of the wire all over the structure. Compared to the conventional method, SHM using wireless sensor network has many challenges like limitations of sampling rate and band width, time synchronization, data communication in large-scale mull-hop network, reliable command dissemination, reliable data collection and high degree of flexibility with response to sensor placements and number of sensors.

This research project is designed to (1) Develop an efficient instrumentation strategy for SHM for tall and mid-rise buildings to monitor their static and dynamic behaviour and assess the structural conditions; Develop numerical models and methods to identify the changes in dynamic behaviours of tall and mid-rise buildings and derive parameters and damage from the experimentally obtained noisy and sparse modal information from wired wireless sensor network, (3) Develop a model capable of health monitoring of existing structure without baseline date, and finally (4) Develop methods to establish the relationship among sensors in terms of patterns of data obtained from them and monitor the patterns to detect potential anomaly in the system.