Structural health monitoring

About: Structural health monitoring is a research topic. Over the lifetime, 11727 publications have been published within this topic receiving 186231 citations.

Guidelines for Structural Health Monitoring

Abstract: This chapter summarizes the state of the art and current developments of guidelines for structural health monitoring (SHM) and performance control. Technical guidelines and standards for condition monitoring and technical diagnostics of rotary machines and for non-destructive testing are not reviewed in this chapter.

Investigation of Wireless Sensor Networks for Structural Health Monitoring

Abstract: Wireless sensor networks (WSNs) are one of the most able technologies in the structural health monitoring (SHM) field. Through intelligent, self-organising means, the contents of this paper will test a variety of different objects and different working principles of sensor nodes connected into a network and integrated with data processing functions. In this paper the key issues of WSN applied in SHM are discussed, including the integration of different types of sensors with different operational modalities, sampling frequencies, issues of transmission bandwidth, real-time ability, and wireless transmitter frequency. Furthermore, the topology, data fusion, integration, energy saving, and self-powering nature of different systems will be investigated. In the FP7 project “Health Monitoring of Offshore Wind Farms,” the above issues are explored.

Computation of structural flexibility for bridge health monitoring using ambient modal data

Abstract: Issues surrounding the use of ambient vibration modes for the location of structural damage via dynamically measured flexibility are examined. Several methods for obtaining the required mass- normalized dynamic mode shapes from ambient modal data are implemented and compared. The method are applied to data from a series of ambient modal tests on an actual highway bridge. Results indicate that for the damage case examined, the flexibility from the ambient mode shapes gave a better indication of damage than the flexibility from the forced-vibration mode shapes. This improved performance is attributed to the higher excitation load levels that occur during the ambient test.

Acoustic Emission Monitoring of Reinforced Concrete under Accelerated Corrosion

Abstract: The development of techniques capable of evaluating the deterioration of reinforced concrete structures is instrumental to the advancement of structural health monitoring (SHM) techniques and service life estimate methodologies for constructed facilities. One of the main causes of degradation is the corrosion of steel reinforcement. This process can be modeled phenomenologically, whereas laboratory tests aimed at studying durability responses are typically accelerated to provide usable results within a realistic period of time. Numerous nondestructive methods have been recently studied. Acoustic emission (AE) is emerging as a nondestructive tool to detect the onset and progression of deterioration mechanisms associated with concrete cracking. In this paper, an accelerated corrosion and continuous AE monitoring test setup is presented, providing relevant information on the characteristics of the corrosion circuit, continuous measurement procedure, selection of AE sensors, and AE parameter setting for data acquisition. The effectiveness of AE in detecting and characterizing the initiation of the corrosion process is discussed on the basis of results from small-scale, precracked RC specimens that are representative of areas near the clear cover in typical RC members. The main outcome is a new approach of AE data interpretation based on time-driven parameters.

Vibration-Based Damage Localization in Flexural Structures Using Normalized Modal Macrostrain Techniques from Limited Measurements

Abstract: : This article presents damage locating indices based on normalized modal macrostrain (MMS) as improvement on the typical curvature-dependent methods. Vulnerability to noise and the use of numerical differentiation procedures are the key factors for the poor performance of many curvature-dependent methods using displacement mode shapes. Whereas dynamic distributed strain measurement data from long-gauge FBG sensors have significantly improved the performance of many damage identification methods, the sensitivity to local damage diminishes as the gauge length increases. The proposed model-free damage identification techniques based on normalized MMS vectors are successfully implemented to locate damage in beam-like structures through numerical simulations and experimental verifications. The unique advantages of the techniques are their simplicity, robustness to noise, ability to precisely identify small damage extents, and localize single and multiple damage states using limited measurable modes from few sensors.