Ying Zhao¹, Mohammad Noori^1,2, Wael A. Altabey^1,3,*, Ramin Ghiasi⁴, Zhishen Wu¹

Structural Durability & Health Monitoring, Vol.13, No.1, pp. 85-103, 2019, DOI:10.32604/sdhm.2019.04695

Abstract This paper introduces a stiffness reduction based model developed by the authors to characterize accumulative fatigue damage in unidirectional plies and (0/θ/0) composite laminates in fiber reinforced polymer (FRP) composite laminates. The proposed damage detection model is developed based on a damage evolution mechanism, including crack initiation and crack damage progress in matrix, matrix-fiber interface and fibers. Research result demonstrates that the corresponding stiffness of unidirectional composite laminates is reduced as the number of loading cycles progresses. First, three common models in literatures are presented and compared. Tensile viscosity, Young’s modulus and ultimate tensile stress of composites are incorporated as… More >

Hu Feng¹, Guanghui Liu¹, Jiansong Yuan^2,*, M. Neaz Sheikh³, Lu Feng⁴, Jun Zhao¹

Structural Durability & Health Monitoring, Vol.13, No.1, pp. 105-121, 2019, DOI:10.32604/sdhm.2019.04864

Abstract The fibre pullout test was conducted to investigate the influence of the water stability on the bond behaviour between the Magnesium phosphate cement (MPC) matrix and the steel fibre. The composition of the MPC-matrix and the immersion age of the specimens are experimentally investigated. The average bond strength and the pullout energy are investigated by analysing the experimental results. In addition, the microscopic characteristics of the interface transition zone are investigated using scanning electron microscopy (SEM). The experimental results showed that the bond performance between the MPC-matrix and the steel fibre decreased significantly with the increase of the duration of… More >

Shengcai Li^1,*, Jun Tang^1,2, Lin Guo³

Structural Durability & Health Monitoring, Vol.13, No.1, pp. 61-84, 2019, DOI:10.32604/sdhm.2019.06058

Abstract The simplified mechanical model and finite element model are established on the basis of the measured results and analysis of the grouting pile deformation monitoring, surface horizontal displacement and vertical displacement monitoring, deep horizontal displacement (inclinometer) monitoring, soil pressure monitoring and seepage pressure monitoring in the lower reaches of Wuan River regulation project in Shishi, Fujian Province. The mechanical behavior and deformation performance of mould-bag pile retaining wall formed after controlled cement grouting in the silty stratum of the test section are analyzed and compared. The results show that the use of controlled cement grouting mould-bag pile technology is to… More >

Jiaqi Zhang¹, Kehai Liu^2,*, Chang Gao¹, Zhanjun Wu¹, Yuebin Zheng¹, Dongyue Gao³

Structural Durability & Health Monitoring, Vol.13, No.1, pp. 41-59, 2019, DOI:10.32604/sdhm.2019.05142

Abstract Probability-based diagnostic imaging (PDI) is one of the most well-known damage identification methods using guided waves. It is usually applied to diagnose damage in plates. The previous studies were dependent on the certain damage index (DI) which is always calculated from the guided wave signals. In conventional methods, DI is simply defined by comparing the real-time data with the baseline data as reference. However, the baseline signal is easily affected by varying environmental conditions of structures. In this paper, a reference-free diagnostic imaging method is developed to avoid the influence of environmental factors, such as temperature and load conditions. The… More >

Vinay Shimpi¹, Madappa V. R. Sivasubramanian^1,*, S. B. Singh²

Structural Durability & Health Monitoring, Vol.13, No.1, pp. 1-40, 2019, DOI:10.32604/sdhm.2019.05951

Abstract In this review article, the past investigations carried out on heritage structures using Ambient Vibration Test (AVT) and Operational Modal Analysis (OMA) for system identification (determination of dynamic properties like frequency, mode shape and damping ratios) and associated applications are summarized. A total of 68 major research studies on heritage structures around the world that are available in literature are surveyed for this purpose. At first, field investigations carried out on heritage structures prior to conducting AVT are explained in detail. Next, specifications of accelerometers, location of accelerometers and optimization of accelerometer networks have been elaborated with respect to the… More >

Hai Qian^1,*, Ding Zhou², Bin Gu¹, Rathnayaka Mudiyanselage D. M. S.³

Structural Durability & Health Monitoring, Vol.12, No.4, pp. 281-298, 2018, DOI:10.32604/sdhm.2018.04618

Abstract The temperature fields in the laminated shells were studied, including open cylindrical shells and cylindrical shells, according to the thermal theory. Analytical solution of the temperature in the shells with the known temperature on the surfaces was present. The thinning layer approach was introduced to simplify the three-dimensional heat conduction equation. Firstly, the layered shell was divided into N thinner layers. The governing equation was simplified by replacing the variable r by r0 in the center line of every thin layer. The general solutions of temperature satisfying the simplified three-dimensional governing equation in single-layered shell were deduced in the cylindrical… More >

Costas P. Providakis^1,*, Stavros E. Tsistrakis¹, Evangelos V. Liarakos¹

Structural Durability & Health Monitoring, Vol.12, No.4, pp. 257-279, 2018, DOI:10.32604/sdhm.2018.04607

Abstract In the present study a new structural health monitoring (SHM) technique is proposed as well as a new damage index based on 2-D error statistics. The proposed technique combines the electromechanical impedance technique (EMI) which is based on the use of piezoelectric Lead Zirconate Titanate (PZT) patches and Scanning Laser Doppler Vibrometry (SLDV) for damage detection purposes of concrete structures and early age monitoring. Typically the EMI technique utilizes the direct and inverse piezoelectric effect of a PZT patch attached to a host structure via an impedance analyzer that is used for both the actuation and sensing the response of… More >

Mengyue He¹, Zhifang Zhang^1,*, Karthik Ram Ramakrishnan²

Structural Durability & Health Monitoring, Vol.12, No.4, pp. 213-256, 2018, DOI:10.32604/sdhm.2018.05122

Abstract Fibre reinforced polymer (FRP) composite laminates are now commonly used in many structural applications, especially in the aerospace industry, where margins of safety are kept low in order to minimise weight. Timely detection and assessment of damage (in particular delaminations) in composite laminates are therefore critical, as they can cause loss of structural integrity affecting the safe operation of the composite structures. The current trend is towards implementation of structural health monitoring (SHM) systems which can monitor the structures in situ without down time. In this paper, first, the current available SHM techniques for delamination detection in FRP composites are… More >

Tongfa Deng^1,2, Junping Zhang^1,3,*, Mahmoud Bayat⁴

Structural Durability & Health Monitoring, Vol.12, No.3, pp. 189-212, 2018, DOI: 10.3970/sdhm.2018.04392

Abstract The isolated curved girder bridge's vibration characteristics play a major part in the seismic responses of structures and anti-seismic properties. A clear analytic relationship between design parameters and the system's vibration characteristics could be established by its simplified dynamic analysis model, making it convenient for providing a reference to the optimization of design and safety analysis. A double-mass six-degree-of-freedom model for curved girder bridges with isolation bearings installed at the top of the bridge piers is built and a simplified analysis method for the vibration characteristics of the system is provided. Combined with the Matlab programming, the influences of radius… More >

Kong Fah Tee ^1,*

Structural Durability & Health Monitoring, Vol.12, No.3, pp. 129-147, 2018, DOI: 10.3970/sdhm.2018.04316

Abstract Structural health monitoring (SHM) is a vast, interdisciplinary research field whose literature spans several decades with focusing on condition assessment of different types of structures including aerospace, mechanical and civil structures. The need for quantitative global damage detection methods that can be applied to complex structures has led to vibration-based inspection. Statistical time series methods for SHM form an important and rapidly evolving category within the broader vibration-based methods. In the literature on the structural damage detection, many time series-based methods have been proposed. When a considered time series model approximates the vibration response of a structure and model coefficients… More >