Zhongguo Tang¹, Haijin Zhuo¹, Beian Li¹, Xiaotao Ma², Siyu Zhao², Kai Tong^2,*

Structural Durability & Health Monitoring, Vol.17, No.5, pp. 407-431, 2023, DOI:10.32604/sdhm.2023.026033

Abstract Corrosion can be very harmful to the service life and several properties of reinforced concrete structures. The metal magnetic memory (MMM) method, as a newly developed spontaneous magnetic flux leakage (SMFL) non-destructive testing (NDT) technique, is considered a potentially viable method for detecting corrosion damage in reinforced concrete members. To this end, in this paper, the indoor electrochemical method was employed to accelerate the corrosion of outsourced concrete specimens with different steel bar diameters, and the normal components BB_z and its gradient of the SMFL fields on the specimen surfaces were investigated based on the metal magnetic memory (MMM) method.… More >

Guanghua Zheng^1,2, Chaolin Luo^1,3, Mengen Shen^1,*, Wanzhong Lv⁴, Wenbo Jiang⁴, Weibo Yang²

Energy Engineering, Vol.120, No.4, pp. 985-1000, 2023, DOI:10.32604/ee.2023.024372

Abstract To solve the problems of low precision of weak feature extraction, heavy reliance on labor and low efficiency of weak feature extraction in X-ray weld detection image of ultra-high voltage (UHV) equipment key parts, an automatic feature extraction algorithm is proposed. Firstly, the original weld image is denoised while retaining the characteristic information of weak defects by the proposed monostable stochastic resonance method. Then, binarization is achieved by combining Laplacian edge detection and Otsu threshold segmentation. Finally, the automatic identification of weld defect area is realized based on the sequential traversal of binary tree. Several characteristic analysis dimensions are established… More >

Fengyu Xu^1,2, Masoud Kalantari³, Bangjian Li², Xingsong Wang^2,*

CMC-Computers, Materials & Continua, Vol.75, No.1, pp. 2209-2226, 2023, DOI:10.32604/cmc.2023.027102

Abstract The automatically defect detection method using vision inspection is a promising direction. In this paper, an efficient defect detection method for detecting surface damage to cables on a cable-stayed bridge automatically is developed. A mechanism design method for the protective layer of cables of a bridge based on vision inspection and diameter measurement is proposed by combining computer vision and diameter measurement techniques. A detection system for the surface damages of cables is de-signed. Images of cable surfaces are then enhanced and subjected to threshold segmentation by utilizing the improved local grey contrast enhancement method and the improved maximum correlation… More >

Mario Bonagura, Lucio Nobile^*

Structural Durability & Health Monitoring, Vol.15, No.2, pp. 125-137, 2021, DOI:10.32604/sdhm.2021.015644

Abstract The compressive strength of concrete is one of most important mechanical parameters in the performance assessment of existing reinforced concrete structures. According to various international codes, core samples are drilled and tested to obtain the concrete compressive strengths. Non-destructive testing is an important alternative when destructive testing is not feasible without damaging the structure. The commonly used non-destructive testing (NDT) methods to estimate the in-situ values include the Rebound hammer test and the Ultrasonic Pulse Velocity test. The poor reliability of these tests due to different aspects could be partially contrasted by using both methods together, as proposed.in the SonReb… More >

Ruixin Zhao^1,*, Zhongju Feng¹, Guan Jiang¹, Fuchun Wang¹, Yidong Zhang², Changan Zhang³, Zhenbing Wang¹

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.2, pp. 441-453, 2021, DOI:10.32604/fdmp.2021.010595

Abstract The present study examines the working conditions of fully grouted bolts used for the construction and expansion of high slopes. On the basis of a pull out destructive test, the work load and the ultimate load are obtained on site, and the Flac3d numerical simulation method is employed to determine the axial force distribution and the effective anchor length. The test results show that (1) the Q-S (load-displacement) curve of the bolt displays a certain degree of deformation coupled with the creep of the surrounding rock; (2) the working load of the bolt is closely related to the sliding deformation… More >

Sanghyo Lee¹, Yonghan Ahn², Ha Young Kim^{3, *}

CMC-Computers, Materials & Continua, Vol.65, No.1, pp. 1-17, 2020, DOI:10.32604/cmc.2020.011104

Abstract In this study, we examined the efficacy of a deep convolutional neural network (DCNN) in recognizing concrete surface images and predicting the compressive strength of concrete. A digital single-lens reflex (DSLR) camera and microscope were simultaneously used to obtain concrete surface images used as the input data for the DCNN. Thereafter, training, validation, and testing of the DCNNs were performed based on the DSLR camera and microscope image data. Results of the analysis indicated that the DCNN employing DSLR image data achieved a relatively higher accuracy. The accuracy of the DSLR-derived image data was attributed to the relatively wider range… More >

Chengquan Wang¹, Yonggang Shen^2,*, Yun Zou¹, Tianqi Li¹, Xiaoping Feng¹

CMES-Computer Modeling in Engineering & Sciences, Vol.114, No.1, pp. 75-93, 2018, DOI:10.3970/cmes.2018.114.075

Abstract The failure behavior of the precast prestressed concrete T girder was investigated by destructive test and finite-element analysis, and the mid-span deflection, girder stiffness and the variation of the cross section strain in the loading process were obtained, and the mechanical properties, mechanical behavior, elastic and plastic behavior and ultimate bearing capacity of T girder with large span were revealed. Furthermore, the relationship between the beam stiffness degradation, the neutral axis in cross-section, steel yielding and concrete cracking are investigated and analyzed. A method was proposed to predict the residual bearing capacity of a bridge based on the variation of… More >

P. Huke, Ralf B. Bergmann

The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.3, pp. 69-70, 2011, DOI:10.3970/icces.2011.020.069

Abstract Non-destructive testing (NdT) describes a wide range of principles and methods for measuring and comparing physical quantities against a nominal condition. Commonly NdT is related the detection of defects in or on solid-state bodies. This may include hidden defects as well as optical appearance (reflectivity, absorbance, polarity), shape, stress, strain and many other characteristics. In many applications contactless NdT is advantageous due to the state of the object in question. Most often optical metrology, like shearography, reflectometry, vibrometry and laser ultrasound, is contactless or needs no physical contact to the measurement area. The optical NdT splits up in two categories.… More >

Y.S. Chen, Y.H. Huang, B. Yeung, L. Liu, Y.Y. Hung

The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.1, pp. 21-22, 2011, DOI:10.3970/icces.2011.020.021

Abstract Active thermography is an optical-based non-contact inspection method for full-field and quantitative measurement of surface radiation to predict potential faults or inner structure of a test object. The mechanism of the active thermography inspection is to excite the test object using appropriate thermal excitation methods and measure the corresponding thermal response. Active thermography conducts testing in a more controllable way and offer more reliable results compared to passive thermography. This paper reports the development of integrated systems featured some advanced excitation methods and thermal image processing methods. Experiments have been conducted on samples with disbonds, delaminations, internal cracks or voids,… More >

Xide Li

The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.1, pp. 13-14, 2011, DOI:10.3970/icces.2011.020.013

Abstract The quantitatively assessment of defect characteristic parameters (DCP), such as coordinates, size, embedding depth and type of defects in structures or materials, is becoming increasingly important. One reason is for economy and safety, and the other for a defect in structures may lead to failure while it is growing to a critical size. Therefore, it is possible to estimate both remaining life of structures and extent of the degradation by knowing the dimensions of defects presenting in structures. In this paper, several research topics on quantitative detection of the DCP in our group are reviewed as follows:
1 )Nondestructive testing… More >