Deformation monitoring of a super-tall structure using real-time strain data

Abstract

Monitoring deformation of super-tall structures under different environmental conditions is an important and challenging issue in assessing the safety and serviceability of structures. This paper presents a new method for calculating structural deformation using real-time strain data, which can be easily measured at different sections. Assuming the structural deformation is of bending beam type, the deformation of the structure is associated with longitudinal strain. Virtual work theory is then used to calculate the horizontal displacement and tilt angle of the building on the basis of the strain data at different heights of the structure. The proposed method is applied to the 600 m tall Canton Tower (previously known as Guangzhou New TV Tower), on which a long-term structural health monitoring system including over 400 vibrating strain gauges has been installed at different heights. The displacements and tilts of the structure top under normal and typhoon conditions are calculated using real-time monitoring strain data. The calculated deformations show good agreement with the measurements by using global positioning system (GPS) and inclinometers. The temperatureinduced maximum daily movement is similar to the value of typhoon-induced motion. Moreover, the displacement mode of the super-tall structure is also calculated and shows the bending type. Error analysis demonstrates that the calculated displacements have higher accuracy than the GPS-measured counterparts, and that the calculated tilts have similar accuracy as those measured by an inclinometer.

Global overview on advances in structural health monitoring platforms

“…In fact, some working sensing systems could also be optimized for the information to be available in a virtual platform, allowing the remote access to the data [24]. This practice has been implemented with the aim of optimizing technical work for the structural assessment in real time [25]. However, the technological advances on SHM do not have as a goal to eliminate the human role in the structural assessment [26], but to offer a high performance tool for the evaluation of structures.…”

“…SHM platforms combining a lower, as possible, number of sensors, and allowing the prediction about the structural risk based on dramatic natural scenarios, are the most attractive, as related in Xia et al [25].…”

“…The error analysis of the sensors system implemented was also verified to be higher than the error values checked by GPS measurements. Therefore, in this work, the authors had demonstrated the use of a large number of synchronized sensors working for SHM, but highlighting the necessity of a data processing implementation for lifetime prediction [25].…”

A Proposal of Model Updating Method for Steel Frame Using Global/Local Responses

“…구조 건전도 모니터링(Structural Health Monitoring) 연 구가 활발히 진행 Park et al, 2013;Xia et al, 2014;Roussel et al, 2014)되어 왔다. 건물 에 설치된 센서로부터 계측한 응답을 이용하여 건물 내 구조 부재들의 안전성을 평가하거나 시스템 식별(system identification)을 통해 시스템 레벨의 상태를 평가한다 (Lamarche et al, 2007;Zimmerman et al, 2009;Chen et al, 2011;Ye et al, 2012).…”

Damage detection with interval analysis for uncertainties quantification

“…A large number of model-based and data-driven damage detection approaches have been proposed for vibration-based SHM (Liu et al 2014, Xia et al 2014, and most of them have been employed successfully on numerical examples and well-controlled lab-scale structures. For in-situ SHM applications, however, the detection results may be unreliable due to uncertainties (Mao 2012).…”