Zhitao Yan

• Chongqing University of Science and Technology

The special configuration and elongated geometrical appearance of the helical strand give it properties of tensile–torsion–bending coupling as well as macroscopic geometrical nonlinearity. Simulating small-scale strands using solid elements in finite element software reproduces these properties but is time-consuming. Current methods of modeling lar...

In this paper, a new image-correction method for flange joint bolts is proposed. A checkerboard is arranged on the side of a flange node bolt, and the homography matrix can be estimated using more than four feature points, which include the checkerboard corner points. Then, the perspective distortion of the captured image and the deviation of the c...

Bolt looseness detection is a common problem in engineering. Most vision-based detection techniques focus on diagnosing ordinary bolt looseness, i.e., the methods used for diagnosis are based only on the sidelines of nuts. These methods cannot be used for anti-loosening bolt looseness diagnosis because of the simultaneous rotation of screws and nut...

Reinforced concrete is a widely used building material in construction. However, under specific corrosive conditions, reinforced concrete structures are prone to corrosion, leading to a gradual decrease in durability and eventual destruction. This review first discusses the causes and mechanisms of degradation of reinforced concrete, and then vario...

This work explored the synergistic effect of Styphnolobium japonicum (L.) Schott extract (SE) and potassium io-dide (KI) on the corrosion inhibition of carbon steel (CS) in 0.5 mol/L H 2 SO 4 solution. Firstly, the functional groups in the SE were identified using FTIR. The results of UPLC-Q-TOF-MS analysis confirmed the major phytoconstituents pre...

The utilization of waste materials as corrosion inhibitors is gaining attention in the field of corrosion science and metallurgy due to its potential for sustainable and cost-effective corrosion control. This chapter explores the promising application of slaughterhouse waste, a readily available and underutilized resource, as corrosion inhibitors....

To make waste more sustainable and environmentally friendly, the criterion for future production processes will be to give waste “new life”. Metal corrosion, spurred by electrochemical reactions with the environment, poses a significant global challenge from both economic and environmental standpoints. Among the current anti-corrosion technologies,...

In this paper, a new perspective rectification method for image of bolts in flange joint is proposed and the image-based bolt-loosening detection process for the flange joint is established. The presented method can correct the perspective distortion for the picture using the four center points of corner bolts in bolt-group connection. However, it...

This study utilized Schizochytrium extract (SE) to explore its protective effect on carbon steel in a 0.5 mol/L H2SO4 solution. The main functional groups of SE were investigated by Fourier infrared spectroscopy (FTIR) and x-ray photoelectron spectroscopy (XPS). The following conclusions were drawn from electrochemical tests: A corrosion inhibition...

The full-field responses and high-resolution mode shapes are of paramount importance in the detection of bridge damage and finite element model updating. As enlightened by the Fourier series expansion of the mode shapes for a bridge, this study proposes an approach for compressive sensing-based reconstruction of the full-field responses and identif...

Distributed plates have been proven effective in controlling the vortex shedding and reducing the drag force of a circular cylinder, but more studies on its effect on vortex-induced vibration (VIV) are needed. This paper presents a systematic study of the effect of distributed cross-plates on the suppression of the VIV of a flexible cylinder using...

Abstract: The objective of this study is to extract amino acids from fish processing discards for the preparation of highly effective and degradable corrosion inhibitors. The composition of fish processing discards extract (FPDE) was characterized by HPLC and FTIR. The results showed that the main components of FPDE are amino acids and contain a la...

The nonlinear effects exhibited by structures under the action of wind loads have gradually stepped into the vision of wind-resistant researchers. By summarizing the prominent wind-induced nonlinear problems of four types of wind-sensitive structures, namely tall buildings, high-rise structures, flexible bridges, and transmission lines, the occurre...

This study employed Benincasa hispida peel as a raw material for the preparation of Benincasa hispida peel extract (BHPE) via hot water extraction and freeze-drying processes. The synergistic effect of BHPE and KI on the corrosion inhibition of mild steel in 1 M HCl was investigated. The compositional analysis shows that BHPE consists mainly of a m...

In this study, corrosion inhibitors from waste protein were extracted, and their anti-corrosion behavior was investigated on a laboratory-scale. The functional groups of the protein waste extract (PWE) were identified using Fourier transform infrared (FTIR) spectroscopy. High-performance liquid chromatography (HPLC) was used to determine the variet...

The shell of viviparid snail extract (SVSE) was prepared by a simple and environmentally friendly hydrolysis method and the corrosion inhibition of carbon steel (CS) by SVSE in 1 M HCl was investigated. HPLC and FTIR analysis showed that the main component of SVSE was a mixture of various amino acids. The results of electrochemical and surface anal...

With the rapid development of computational fluid dynamics (CFD) technology, it has been widely used to study the wind field characteristics of downbursts in mountainous areas. However, there is little guidance on the selection of different turbulence models for simulating downburst wind fields over hills using CFD, and few comparative studies have...

Existing studies have found that curved beam unilateral stayed bridges (CBUSB) have a risk of cable breakage under the design wind velocity. To ensure structural wind-induced vibration security, it is necessary to study the wind-induced vibration characteristics of CBUSBs considering the influence of the impact load due to the cable breakage. Based...

Corrosion is the process of damaging materials, and corrosion of metallic materials frequently results in serious consequences. The addition of corrosion inhibitors is the most effective means of preventing metal corrosion. Until now, researchers have made unremitting efforts in the research of high-efficiency green corrosion inhibitors, and resear...

This paper presents a formulation for estimating scale factors based on the vehicle-induced variation of bridge frequencies. The scale factors of mass-normalized mode shapes are formulated to avoid dealing with randomly-scaled mode shapes from output-only modal tests. To this end, the variations of higher-order bridge frequencies and mode shapes du...

Ice shedding of transmission lines may lead to interphase flashover and thereby endanger power transmission. The ice shedding of transmission lines is essentially an energy conversion process. Based on the vibration theory and energy method of cable structures, the iced load of a transmission line is regarded as the working load under the condition...

Numerical simulation of transmission lines’ movement can reveal the variation of aerodynamic force with conductor vibration. The fluid-structure interaction is considered and, and the software FLUENT is used to numerically analyze the model responses of 0.75D crescent-shaped iced conductor with wind attack Angle of 180° based on the k-ω SST turbule...

In this work, a self-supplied electron photoelectrochemical (PEC) biosensor for sensitive determination of Pb2+ was established by utilizing donor-acceptor (D-A)-type PTB7-Th (poly{4,8-bis[5-(2-ethylhexyl) thiophen-2-yl]benzo[1,2-b,4,5-b']dithiophene-2,6-diyl-alt-3-fluoro-2-[(2-ethylhexyl)carbonyl] thieno[3,4-b]-thiophene-4,6-diyl}) as a photoelect...

This study presents an eco–friendly and high–efficiency corrosion inhibitor for carbon steel in 1 M hydrochloric acid (HCl) extracted from Reineckia carnea. Electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PD) were conducted to evaluate the anti–corrosion performance of Reineckia carnea extracts (RCE) for carbon steel...

In this work, the corrosion inhibition properties of FJLE in chlorine–containing simulated concrete pore solution (SCPS) were investigated by aqueous extraction of FJLE leaves. Fourier Transform Infrared Spectrometer (FTIR) and High–Performance Liquid Chromatography (HPLC) were used to determine the main components of FJLE. The corrosion inhibition...

The linear curve distribution of the beam and the asymmetrical layout of the stay cables may have beneficial or adverse influences on cable-stayed bridges. Sectional model wind tunnel tests and numerical simulations were used to analyze the influence of these two factors on the wind-induced vibration characteristics of a curved beam unilateral stay...

The complex aerodynamic shape and structural form affect the wind-induced vibration coefficient β of landscape towers with a twisted column and spiral beam (short for LTs). To clarify the β distribution characteristics, evaluate the applicability of existing load codes, and provide accurate design wind loads, wind tunnel tests and numerical simulat...

Plant extracts with the advantages of environment–friendly, renewable and rich resources, can be used as promising corrosion inhibitors in pickling or descaling processes. In this study, the inhibition performance and inhibition mechanism of Nandina domestica Thunb. extract (NDTE) for carbon steel in HCl solution was evaluated by electrochemical ex...

At present, an important goal in the field of corrosion is to develop effective and environment–friendly corrosion inhibitors. Newly developed corrosion inhibitors can be used to substitute conventional corrosion inhibitors, which are toxic and undegradable. Herein, Artemisia argyi leaves extract (ALE) as high–efficiency corrosion inhibitor of carb...

Herein, an efficient and feasible photoelectrochemical (PEC) biosensor based on gold nanoparticle-decorated graphitic-like carbon nitride (Au NPs@g-C3N4) with excellent photoelectric performance was designed for the highly sensitive detection of mercury ions (Hg2+) . The proposed Au NPs@g-C3N4 was first modified on the surface of the electrode, whi...

In this paper, a new natural frequency identification method is proposed for the modal parameter identification under an unknown colored noise excitation. The presented method can effectively eliminate the influence of incentive frequency on the identification of the natural frequencies when there are several colored noise excitations applied to th...

Digital twins (DTs) can realize the integration of information and entities. It is widely used because of its simulation characteristics and virtual reality (VR) mapping. Its application to industrial product management and control is explored. First, the concept and the functions in different stages of DTs are expounded. Second, the Workench simul...

A simplified calculation method is proposed for determining the peak dynamic windage yaw angle φ ^ of electricity transmission line (TL) tower suspension insulator strings (SISs). According to the rigid-body rule, the geometric stiffness matrix in the calculation of the windage yaw angle φ of SISs is dominated by the average wind loads, while the f...

Expanded polystyrene (EPS) concrete is commonly used as the core material of commercial sandwich panels (CSPs). It is environmentally friendly and lightweight but has poor strength. Adding fibers can improve the microstructure of EPS concrete and reduce the weakening effect of EPS beads on the mechanical properties of concrete. An orthogonal experi...

In this work, the degradation of mechanical properties of galvanized steel under wind and sand erosion environment was studied. The law of weight loss of galvanized steel in corrosive environment was studied by accelerated corrosion experiment. The micro-morphology and formation mechanism of corrosion products were investigated in detail by scannin...

Metallic materials are widely utilized in the fields of industry, agriculture, transportation and daily life for their high mechanical strength, and relatively low cost. However, the microorganisms that are widely distributed in surroundings can have complicated interactive reactions with metallic materials. The microbiologically influenced corrosi...

In this work, Centipeda minima leaves extract (CMLE) was prepared by facile hot–water immersion extraction and freeze–drying with Centipeda minima leaves as raw material. The potentiodynamic polarization curves (Tafel), electrochemical impedance spectroscopy (EIS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM),...

In order to solve the problem of black pollution in the 21st century, a new type of rubber ceramsite concrete was prepared by pulverizing waste rubber tires into granules and adding aggregate to the ceramsite concrete. In order to reduce the weakening of mechanical properties of rubber, basalt fiber was used to modify the rubber. In this study, the...

Wind loads on a surface-mounted finite-height circular cylinder are strongly influenced by the flow field structure. Based on the stationary and moving downburst flows simulated by an impinging jet device, this paper studies the wind pressure distribution in a circular cylinder with a low aspect ratio of AR = 2 at different radial positions and dis...

Substation down conductor structure system is generally bundled conductor, and has the characteristics of small span, large height difference, short length and upper and lower connection. Substation lead-down accidents caused by strong wind often occurs. Down conductor accidents of substation caused by strong wind often occur. In order to study the...

Steel core aluminum stranded wire, its abbreviation is ACSR, is a classic multi-stranded wire composed of different materials. Many scholars have used static experiments to study the mechanical properties of steel wire rope structures [1] . In this paper the author use the finite element software ANSYS to carry out numerical simulation on the alumi...

The K2 formation of C68 block is explored by injecting water to maintain formation pressure, but the continuous decrease of injection rate significantly reduces oil production. Therefore, it is important to predict scaling tendency of injected water in the formation. Firstly, ion composition of formation water and injected water was tested accordin...

Expanded polystyrene (EPS) concrete is a core material in sandwich panels, and EPS beads are widely believed to be nonuniformly distributed in the panels. However, the effectiveness of attempts to improve the homogeneity has been difficult to prove because of the lack of a direct method to quantitively evaluate a nonuniform distribution. Based on t...

This investigation aims to study the flexural behaviour of reinforced concrete (RC) beams strengthened with near-surface mounted (NSM) carbon fibre reinforced polymer prestressed concrete prisms (CFRP-PCPs). Eight RC beams were tested under monotonic loading until the failure load was reached. One beam was un-strengthened to act as a control beam....

Appropriate design wind loads can effectively avoid damage to transmission towers under strong wind and the wind-induced vibration coefficient β(z) is a critical parameter for determining those loads. Based on the inertial load approach, a step-by-step calculation method for the design wind loads of transmission towers considering the effects of cr...

The lateral bearing performance of a defective pile-supported wharf located on a slope was investigated through centrifuge modeling, and a numerical model was employed to back-analyze the centrifuge test data. The pile foundation system was composed of double-plumb, single-plumb, and batter piles, and the defects were located at the front row of th...

As a new breakwater foundation form, a bucket foundation with two skirted side semicircles and a skirted middle rectangle was applied to the breakwater project at Xuyu Port, China. A series of laboratory tests were performed on the bucket foundation to investigate the vertical bearing capacity and the bucket-sand interaction mechanisms during the l...

The effects of Reynolds number (Re) and surface roughness on the wind pressure coefficient on a MAN type dry gas tank were analyzed in detail by wind tunnel tests. A wind load calculation model was then established, which is suitable for the wind resistant design of the gas tanks. The test results revealed that in the range of 7 × 10⁵ < Re < 1.0 ×...

A new type of caisson, composed of two skirted side semicircles and a skirted middle rectangle, was used as a breakwater foundation in Xuyu Port, China. In this study, large-scale laboratory model tests were carried out on jacking installations and lateral loading of this new skirted foundation in sand. Test results showed that the soil pressure ac...

Model tests aimed at investigating the wave-induced pore pressure responses of a silty clay seabed around a vertical caisson breakwater were conducted with a large-scale bespoke wave-breakwater-seabed system. The effects of water depth, wave parameters, and seabed consolidation conditions on oscillatory pore pressure were investigated. The residual...

The proposed Sutong long-span electric transmission line is the highest tower-line system with the longest span so far, and thus mainly affected by wind load. Wind tunnel tests of the aeroelastic model are effective ways to further study these wind-induced coupled vibration phenomena. While due to the limit of wind tunnel conditions and model mater...

Model tests aimed at investigating the wave-induced dynamic response and instability of silty clay seabeds around a semi-circular breakwater were conducted in a large wave flume. The pattern of wave forces was measured and analysed. The seabed responses were presented in terms of pore pressure and vertical stress, which were further characterized i...

3D simulations based on an impinging jet were carried out to investigate the flow field of a steady downburst and its effects on a high-rise building by applying the SST k-ω turbulence model. The vertical profile of radial wind speed obtained from the simulation was compared with experimental data and empirical models in order to validate the accur...

In order to study the mechanism of the breeze vibration of transmission lines, based on the non-linear model of Scanlan's experience, the finite element motion equation of the transmission line's breeze vibration is derived, and the dynamic solution is carried out. The results show that the parameters of Scanlan vortex force have a significant infl...

To reveal the mechanism of aeolian vibration on transmission line, the steady amplitude of aeolian vibration is calculated based on the principle of energy balance, and the correction coefficient of amplitude is proposed under considering the non-uniformity coefficient of wind turbulence, environmental conditions and other factors; then the balance...

The wind forces on the steel lattice structures have drawn increasing concerns in the structural design of high-rise and long-span buildings and structures due to their low damping, light self-weight, and high flexibility. The aim of this paper is to assess the aerodynamic forces on circular steel tubular lattice structures with vertical and inclin...

Wind tunnel tests were carried out to obtain the static aerodynamic characteristics of crescent iced 4-bundled conductors with different ice thicknesses, initial ice accretion angles, bundle spaces, and wind attack angles. The test models were made of the actual conductors and have a real rough surface. Test results show that the influence of wake...

To investigate the wind load distribution of cross-rope suspension tower with occlusion, and provide theoretical basis for wind resistant design, a single-mast and double-mast systems were tested by high-frequency force balance in wind tunnel in type-B landform turbulent flow and uniform flow fields. The influence of shielding effect on the power s...

The galloping or vortex-induced vibration of transmission lines will lead to a periodic excitations to the masts of the cross-rope suspension tower (CRST). The mast of the CRST is modeled as a straight beam with an elastic support subjected to a pulsating axial force on the top, which will change the stiffness of the mast, thereby resulting in prod...

Post-cyclic undrained strength degradation happens to the saturated soft clay under wave cyclic loading for the excess pore pressure produced, resulting in the significant loss of bearing capacity of the breakwater. Based on the development model of pore pressure and the rule of shear strength of normally consolidation soft clay, the dynamic degrad...

The lattice Boltzmann (LB) model has advantages of simple programming and faster operation, but for images with low contrast and noise, segmentation may fail. This paper proposes a novel LB model using local statistical region information. As the method can enhance contrast of the object and background, and reduce noise, it provides improved deline...

Pittsburgh compound B Positron Emission Tomography (PiB-PET) imaging is a new technology for detecting amyloid-beta peptide (Aβ. Aβ is a pathological bio-data that distinctly appears in most neuro-degeneration diseases, such as Alzheimer’s disease (AD). The 3D segmentation of Aβ in PiB-PET images aids radiologists in diagnosing AD. However, the exi...

The wind-induced responses of a cross-rope suspension tower-line are dramatically different from those of the self-supported UHV transmission tower-line. Aero-elastic wind tunnel tests were used to investigate the wind-induced responses of the cross-rope suspension tower-line, changing with the wind direction angle and the test velocity. Tests on b...

The dynamic characteristics of a MAN type dry gas storage tank are very complex, they are different from those of ordinary spatial structures. Here, as the basis of its wind-induced response analysis in frequency domain, its dynamic characteristics were analyzed under different working conditions by using the finite element method. Its modes were s...

The effect of guy initial tension on wind-resistant performance of a ±800kV direct current (DC) cross-rope suspension tower-line was investigated through an aero-elastic model test in a boundary layer wind tunnel. Three kinds of guy initial tensions (15%, 20%, and 25% of the ultimate stress) were selected. The results showed that the changes of guy...

Based on high-frequency-force-balance technique, a model of an occluded latticed tower was tested in a wind tunnel under conditions of 3 kinds of wind speed, and 6 kinds of occluding distance to investigate mean force coefficients and power spectral densities(PSDs) of base moment. Based on these results, the analytical models of PSD for the base mo...

The cross-rope suspension (CRS) tower has been widely used in the ±800 kV DC project from Hami to Zhengzhou. The CRS tower configuration is simple in both concept and design. It consists of two guyed masts that support the "cross-rope" conductor suspension system. However, it is sensitive to wind loads. An aero-elastic wind tunnel test was carried...

An analytical approach to solving the galloping model for iced transmission lines based on curved-beam theory and considering elastic boundary condition was developed and can contribute to understanding the galloping mechanism. A two-degree-of-freedom galloping model is reduced from a three-degree-of-freedom galloping model according to the frequen...

The galloping model of an iced transmission line based on the conventional cable theory cannot consider coupling between the translation and torsion and torsion nonlinearity. According to Hamiton principle and Galerkin method, a 3-DOF curved-beam model of an iced transmission line considering stiffnesses of insulator strings and adjacent spans as b...

Long span transmission bundle lines will more easily suffer galloping phenomenon than a single wire. Based on space-curved-beam theory, the finite element model based on 6-DOF node is built to simulate a transmission line. The spacers are assumed as a rigid body, and the finite element model of 4-bundle conductors is established according to the di...

Chaotianmen Yangtze River Bridge in China is a semi-supporting, steel-truss, and tied arch bridge with a main span of 552 m, marking the world's longest center span of the same type. The wind-resistant behavior under yaw winds was investigated via wind-tunnel tests of 1:100 scale-downed full bridge aeroelastic models. The service stage and four key...

A long span transmission line may be set into the aeolian cross-wind periodic oscillation of a high-frequency, low amplitude by relatively low wind velocity. Based on spatial curved beams interpolation functions and the strain-displacement relations of spatial curved beam theory, the finite element model of the transmission line which have 6 DOF no...

The galloping of iced transmission lines is a kind of strongly nonlinear vibration. The incremental harmonic balance method is employed to establish the finite element model and balanced equations of iced conductor vibration. Then, vibration balanced equations were solved, which include the square and cubic stiffness items, square and cubic viscous...

The coupling between translational and torsional movements and the non-linearity cannot be considered in traditional galloping transmission line analytical model with 3-DOFs nodes. Based on the strain-displacement relations of spatial curved beam theory, the finite element model of iced transmission line galloping was proposed, with the nodes conta...