Long Term Application of a Vehicle-Based Health Monitoring System to Short and Medium Span Bridges and Damage Detection Sensitivity

Due to the long-term service, Chinese ancient timber buildings show varying degrees of wear. Thus, structural health monitoring (SHM) for these cultural and historical treasures is desperately needed to evaluate the service status. Although there are some FBG sensing-based SHM systems, they are not suitable for Chinese ancient timber buildings due to the differences in architectural types, structural loads, materials, and environment. Besides, a technical gap in Fiber Bragg grating (FBG) sensing-based column inclination monitoring exists. To overcome these weaknesses, this paper develops an FBG sensing-based structural health monitoring system for Chinese ancient Chuan-dou-type timber buildings that aims at monitoring structural deformation, i.e., beam deflection and column inclination, temperature, humidity, and fire around the building. An in-situ test and simulation analyses were conducted to verify the effectiveness of the developed SHM system. To validate the long-term-operation of the developed SHM system, monitoring data within 15 months were analyzed. The results show good agreement between the developed SHM system in this paper and other methods. In addition, the SHM system operated well in the first year after its deployment. This implies that the developed SHM system is applicable and effective in the health state monitoring of Chinese ancient Chuan-dou-type timber buildings, laying a foundation for damage prognosis of such types of timber buildings.

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An open database for benchmarking guided waves structural health monitoring algorithms on a composite full-scale outer wing demonstrator

Structural Health Monitoring ◽

10.1177/1475921719889029 ◽

2019 ◽

Vol 19 (5) ◽

pp. 1524-1541 ◽

Cited By ~ 1

Author(s):

Alessandro Marzani ◽

Nicola Testoni ◽

Luca De Marchi ◽

Marco Messina ◽

Ernesto Monaco ◽

...

Keyword(s):

Structural Health Monitoring ◽

Damage Detection ◽

Monitoring System ◽

Health Monitoring ◽

Guided Wave ◽

Full Scale ◽

Composite Panel ◽

Health Monitoring System ◽

Electromechanical Impedance ◽

Structural Health

This article reports on the creation of an open database of piezo-actuated and piezo-received guided wave signals propagating in a composite panel of a full-scale aeronautical structure. The composite panel closes the bottom part of a wingbox that, along with the leading edge, the trailing edge, and the wingtip, forms an outer wing demonstrator approximately 4.5 m long and from 1.2 to 2.3 m wide. To create the database, a structural health monitoring system, composed of a software/hardware central unit capable of controlling a network of 160 piezoelectric transducers secondarily bonded on the composite panel, has been realized. The structural health monitoring system has been designed to (1) perform electromechanical impedance measurement at each transducer, in order to check for their reliability and bonding strength, and (2) to operate an active guided wave screening for damage detection in the composite panel. Electromechanical impedance and guided wave measurements were performed at four different testing stages: before loading, before fatigue, before impacts, and after impacts. The database, freely available at http://shm.ing.unibo.it/ , can thus be used to benchmarking, on real-scale structural data, guided wave algorithms for loading, fatigue, as well as damage detection, characterization, and sizing. As an example, in this work, a delay and sum algorithm is applied on the post-impact data to illustrate how the database can be exploited.

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Computation of Wave Propagation in Damped Specimen for Damage Detection

Materials Science Forum ◽

10.4028/www.scientific.net/msf.783-786.2296 ◽

2014 ◽

Vol 783-786 ◽

pp. 2296-2301 ◽

Cited By ~ 1

Author(s):

Veena Jawali ◽

Prakash Parasivamurthy ◽

Ashwini Nagesh

Keyword(s):

Structural Health Monitoring ◽

Damage Detection ◽

Monitoring System ◽

Health Monitoring ◽

Time Of Flight ◽

Source Location ◽

Wave Source ◽

Health Monitoring System ◽

Structural Health ◽

Structural Health Monitoring System

Aim of a structural health monitoring system must be to collect sufficient information about the damage for appropriate remedial measures to be taken to ensure safety. The preliminary step in the process of damage assessment is locating the damage .One of the challenges faced by the structural health monitoring system is monitoring in-flight damages. Localization of in-flight damages or sudden impacts can be achieved by monitoring the acoustic emissions in real time mode. In this paper, an approach based on the employment of Piezo-electric transducer rosettes to locate the acoustic emission source in an aluminum plate is presented. Using the strain gage rosette concepts adapted for piezoelectric transducers, the wave strain principal angles are determined. When two rosettes are used, the intersection of the principal wave strain directions detected by the rosettes gives the wave source location. The method does not require the knowledge of wave velocity in the medium in contrast to the time of flight based location. Hence, this technique can be used in anisotropic or complex structures where the source localization using the conventional time of flight method is difficult. The principal strain angle using the voltage response of the transducers and the rosette principles are obtained and the co-ordinates of the wave source location are calculated using the co-ordinates of the centroids of the rosettes in MATLAB.According to the tests, the rosette piezo-transducer outperforms the single piezo elements to a degree justifying its complexity. The rosette piezo transducer provides more damage related information compared to single elements and hence the performance of the damage detection system can be significantly improved if rosettes are used.

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Probabilistic corrosion fatigue life assessment of a suspension bridge instrumented with long-term structural health monitoring system

Advances in Structural Engineering ◽

10.1177/1369433217698345 ◽

2017 ◽

Vol 20 (5) ◽

pp. 674-681 ◽

Cited By ~ 5

Author(s):

XW Ye ◽

T Liu ◽

YQ Ni

Keyword(s):

Fatigue Life ◽

Structural Health Monitoring ◽

Monitoring System ◽

Corrosion Fatigue ◽

Health Monitoring ◽

Welded Joint ◽

Health Monitoring System ◽

Structural Health ◽

Structural Health Monitoring System

The long-term performance of engineering structures in a corrosive environment will be significantly affected by the coupled action of corrosion and fatigue. In this article, a probabilistic corrosion fatigue analytical model is proposed by taking into account the effects of corrosion-induced reduction of the cross-sectional area and deterioration of the fatigue strength of structural components. The proposed model is exemplified to evaluate the probabilistic corrosion fatigue life of a typical welded joint in the suspension Tsing Ma Bridge instrumented with a long-term structural health monitoring system. A genetic algorithm–based mixture parameter estimation method is developed to facilitate the multimodal modeling of stress spectrum derived from the long-term monitoring data of dynamic strain. The achieved results demonstrate that with the increase in the service life, the reliability index of the investigated typical welded joint is dramatically reduced under the combined effect of corrosion and fatigue.

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Computer Aided Health Monitoring System for Super-Huge Spacial Cable Structures

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.163-167.2824 ◽

2010 ◽

Vol 163-167 ◽

pp. 2824-2829

Author(s):

Qi Lin Zhang ◽

Da Lin Li

Keyword(s):

Monitoring System ◽

Health Monitoring ◽

Design Method ◽

Complex Structures ◽

Health Monitoring System ◽

Analysis Theory ◽

Computer Based ◽

Roof Design ◽

Relative Analysis

Increasingly large and complex structures make it more complicated in analysis, designing and construction, and through the amplification effect caused by the interaction of various parts of the structure, any tiny error in any link could cause huge damage to the building. However, the relative analysis theory and design method are not consummate enough to assess the influence of all kinds of errors. Under this circumstance, structural health monitoring system is an important guarantee to ensure the safety of the structures in both construction and operation stage, and at the same time contributes to make up for the deficiency of theory [1-2]. The Expo Axis project is the largest single project in Expo Site 2010 Shanghai. The Expo Axis project has adopted a whole new architecture form. The roof design as giant light cable-membrane structure about 1000 meter long and about 80 meter width. The computing displacement of the membrane roof is close to 4m. In order to ensure the safety of this structure, a real-time and long-term computer based health monitoring system is applied in the Axis structures.

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