Slip Values Research Articles

Study on the adhesive property of sludge-modified magnesium phosphate cement reinforcement coating for steel bars

The synergistic interaction inreinforced concrete systems originates from the strong bond between steel reinforcement and concrete, enabling them to collaborateunder load and optimize structural performance. This study applied various sludge-modified magnesium phosphate cement mixtures to the surfaces of plain round steel bars and ribbed steel bars to prepare steel-reinforced concrete specimens. The characterization of the bond performance of the sludge-modified magnesium phosphate cement reinforcement coating for steel bars and concrete was achieved through analyzing the failure modes, bond strength, and slip values of different groups. Microscopic analysis was performed using a scanning electron microscope. The results revealed that the primary failure mode of the steel-reinforced concrete specimens was steel bar pull-out, with some specimens exhibiting concrete splitting failure. Coating application on plain round steel bars increased bond strength, while on ribbed steel bars, it decreased bond strength. The application of the coating slightly reduced slip values to some extent.

Effect of coarse aggregate concentration on the bond properties between steel rebar and concrete within low and medium strength range

Most of the current rules and practices employ medium and high-strength concrete with ribbed rebar. However, there are still many structures that are of low concrete class with non-standard aggregate gradation and also contain plain rebar. In this study, to better understand the behavior of such structures, concrete mixtures with 3 different water-to-cement (W/C) ratios (0.6–0.9–1.2) and 4 different coarse aggregate concentrations (CAC) (0 %-20 %-40 %-60 %) were produced. Compressive strength (CS), elasticity modulus (MOE), and splitting tensile strength (STS) tests were performed on the concrete samples, and the stress-strain relationship was determined. Bond-slip behavior was examined on samples containing both plain and ribbed rebars. The results showed that 40 % CAC mixtures had the highest CS and 60 % CAC mixtures had the highest MOE. Adding coarse aggregate increased STS, bond strength (τu), and residual bond stress (τr). The results obtained from this study were also combined with a similar study conducted on medium and high-strength concrete, and models were proposed for CS, MOE, and τu, τr. It was determined that similar to compressive strength, the MOE was also effective on bond strength significantly. A machine learning method (random forest regression) and feature importance analysis were performed to support the results. The results revealed that CS has the most significant effect on τu and τr, but the effect of MOE and STS was also very significant. Additionally, τr/τu and the s1 (slip value at τu), which is proposed as a constant value in existing studies, increased with increasing CS.

Development of CuO/ZnO/Al2O3-hydrotalcite −based catalysts for middle temperature water gas shift reaction: Impact of calcination temperature and residual carbonates

A series of Cu/ZnO/Al2O3 catalysts are synthesized using a reverse co-precipitation method and subjected to calcination at different temperatures ranging from 300 to 650 °C. Characterization of the resulting powders is carried out through ICP, N2-physisorption, XRD, TGA, H2-TPR, N2O chemisorption and SEM techniques. Subsequently, the catalytic performance of the final samples is assessed in the medium-temperature water gas shift reaction across a broad temperature range from 200 to 330 °C. The precursor predominantly featured a hydrotalcite-like structure, undergoing decomposition through three main stages by losing structural H2O and CO2 molecules. All catalysts demonstrated stable performance without by-products during accelerated aging under reaction conditions. The results revealed that the partial elimination of carbonate ions at 300 °C resulted in easily reducible and consequently less thermally stable active sites. For calcined samples at 450 °C and 550 °C the thermal sintering played a pivotal role, leading the less copper surface area and subsequently higher CO slip values. In the case of the calcined sample at 650 °C, despite larger CuO and ZnO crystals, a trade-off between the emission of high-temperature carbonates and thermal sintering led to acceptable activity and thermal stability. Ultimately, the highest Cu surface are of 222 m2gr cat −1 along with the lowest amount of CO slip are observed for calcined sample at 350 °C, attributed to an optimal amount of carbonate, resulting in the superior catalytic performance. This effective balance between thermal sintering and the amount of residual carbonates yielded a final catalyst with outstanding activity and stable performance.

A numerical approach to radiative ternary nanofluid flow on curved geometry with porous media and multiple slip constraints

AbstractEnergy scarcity is among the biggest global challenges which is aggravating with each passing day due to ever increasing energy demands of contemporary livings as well as industrial requirements verses finite and rapidly depleting fossil reserves of our planet. Improving energy efficiency is one of the effective ways to cope with this challenge. Ternary nanofluids (TNF) are a dynamic novel class of fluids possessing unique thermophysical and other functional characteristics making them the most efficient heat transporting fluids of 21st century. These fluids have promising applications in major manufacturing and processing industries, emerging nanotechnologies and bio‐medical domains. The novel theme of this pragmatic study is analysis of bio‐convective TNF flow by stretchable porous curved surface considering effects of thermal radiation, chemical reaction, magnetic field, and various slip constraints. The modeled partial differential equations (PDEs) governing fluid flow under presumptions are converted to ordinary differential equations (ODEs) by suitable transformation relations. Numerical solutions are presented in graphical sketches and tabular forms using MATLAB bvp4c package for physical interpretations of sundry controlling variables impacts. To gauge veracity of computed results, comparisons with already published results have been presented. Moreover, the statistical concept of Pearson correlation coefficient has been employed to prove strong relationship between slip parameters and physical quantities. Research concludes that thermal efficiency of TNF improves by rising velocity slip, magnetic force, curvature factor, thermal radiation, and thermophoresis effects. Velocity slip and thermal slip improve concentration boundary layer. Gyrotactic microorganisms’ density improves for higher velocity slip, temperature slip while depreciates for larger values of nanoparticle concentration slip and motile organism density slip.

Innovative demountable steel-timber composite (STC) beams: Experimental full-scale bending tests

This study introduces an innovative demountable steel-timber composite (STC) flooring system with potential for reuse. The flooring system consists of downstanding hot-rolled I-shaped steel profiles and laminated veneer lumber (LVL) slabs connected to the steel beams with novel shear connectors. This STC flooring system aimed at reducing embodied carbon and optimizing the use of resources, offer an alternative to traditional, carbon-intensive flooring systems. The novel shear connections implemented in the STC beams facilitate demountability, adaptability, reconfiguration, and relocation of structural components, aligning with circular economy principles. Moreover, this flooring system exhibits significant promise for modularization, standardization, and off-site serial production, making it ideal for prefabrication in standard sizes and modules. Two full-scale STC beams, each with a span of 10 m, an LVL slab width of 2.51 m and thickness of 144 mm connected to a steel profile IPE 400, were simply supported and tested in six-point bending to assess their flexural response. The two tested beams were identical in terms of geometry, materials, and shear connection distribution, but differed in the type of shear connection implemented. This contribution outlines the details of the innovative flooring system and the novel connections that enable demountability and reusability of the components. Specifics of the two STC beam specimens, their assembly, the test setup, the instrumentation, and the testing procedure are presented. The results of the two full-scale bending tests demonstrate their significant load-bearing and deformation capabilities as well as potential for reuse. Additionally, the results indicate the efficacy of the novel shear connections and the beams' overall structural integrity. Despite the extensive deformation of the STC beams, the shear connections remained undamaged and slip values of less than 7 mm were recorded in the last loading stages. Within the elastic range, maximum slip values of less than 1 mm were recorded, highlighting the structural components' potential for reuse. Midspan deflections exceeding l/20 demonstrate good ductility. Strain measurements on the timber slabs revealed that the slabs' width was not fully utilized, leading to the determination of an effective width of l/5.5.

Computational Fluid Dynamics Analysis of Slip Flow and Heat Transfer at the Entrance Region of a Circular Pipe

In the era of sustainable development goals (SDGs), energy efficient heat transfer systems are a must. Convective heat transfer within circular pipes is an important field of research on a rarely addressed limitation of fluid flows. Vacuum solar tubes is one of many applications that could benefit from the existence of nanoparticles, Al2O3, for example, to enhance the heating of air or water steam. The current research investigates the impacts of the Reynolds number (Re), Prandtl number (Pr), Knudsen number (Kn), aspect ratio (x/Dh), and volume fraction of Al2O3 nanoparticles (ϕ) on the Nusselt number (Nu) under constant wall heat flux conditions. An axisymmetric computational fluid dynamics (CFD) analysis of the nanofluid flowing at the entrance region of a circular pipe was conducted under a slip flow at steady-state developing laminar conditions using the Ansys-Fluent 2018 software package. A mesh sensitivity analysis was conducted, and a proper number of mesh elements was selected. The results showed that an increasing Re and/or ϕ would result in an increasing Nu. The dependance of Nu on Kn was strong due to the high slip values and temperature jump. An increasing x/Dh ratio resulted in reduced Nu values. The major impact was due to Kn, which caused a reduction of up to 40% in the Nu value due to slip conditions. However, there was an enhancement of 2.5% in the heat transfer due to the addition of nanoparticles, which was found at Re = 250, Kn = 0.1, and ϕ = 0.1 (Pr = 0.729). Finally, Nuavg, Nux, U/Um, and ReCf were corelated with Kn, Pr, Re, and x/Dh with proper coefficient of determination (R2) values.

Bond of steel bars in S-PVA-HF concrete with different cooling methods after high-temperature exposure

This experimental study compared the effect of natural cooling and water spray cooling on the bond properties of steel and steel-PVA hybrid fiber (S-PVA-HF) concrete after being exposed to high temperatures. Twenty-seven plain concrete specimens and fifty-four S-PVA-HF concrete specimens were designed for pullout tests using different cooling methods from high temperatures. This paper explored the bond strength and slip of steel bars and S-PVA-HF concrete with different temperatures and fiber admixtures after cooling from a high temperature. The differences and characteristics of the loss of bond properties of steel bars and S-PVA-HF concrete after natural cooling and water spray cooling were revealed. Phenomena during the heating process and changes in the apparent characteristics and mass burn-off rate after high-temperature exposure were analyzed The results showed that the bond strength and ductility of the specimens mixed with fibers were higher after high-temperature exposure compared with the normal concrete specimens. The bond strength of the specimens decreased upon increasing the temperature. Water spray cooling resulted in a greater loss in bond strength than natural cooling, but it improved the ultimate slip value of reinforced concrete. The ultimate slip value for normal concrete, P1S8 (mixed fiber concrete with 0.1 % PVA fiber + 0.8 % steel fiber), and P1S14 (mixed fiber concrete with 0.1 % PVA fiber + 0.8 % steel fiber) concrete specimens were improved by 8.54 %, 5.36 %, and 8.19 %, respectively.This shows that water spray cooling improved the ductility of concrete. The relationship between ultimate bond strength and ultimate slip value of steel bars and S-PVA-HF concrete after different cooling methods from high temperatures was developed.

Mixed Convection Flow of MHD Casson Nanofluid over a Vertically Extending Sheet with Effects of Hall, Ion Slip and Nonlinear Thermal Radiation

This manuscript investigates the effects of viscous dissipation, Ohmic heating, nonlinear thermal radiation, chemical reactions, Hall current, and ion slip on the mixed convection flow of magnetohydrodynamic (MHD) Casson nanofluid over a vertically stretching sheet in a spongy medium. The strongly nonlinear ordinary differential equations (ODEs) derived from the governing equations are solved using a sixth-order, seven-stage Runge–Kutta (RK6) method in conjunction with the shooting technique. Numerical simulations are conducted using an open-source Python programming language. The study evaluates temperature, velocity, nanoparticle concentration, skin friction coefficients, Nusselt number (rate of heat transfer), and Sherwood number (rate of mass transfer) based on dimensionless parameters. Key findings reveal that increasing ion slip and Hall currents enhance the velocity profile in the x-direction, while the Casson parameter exerts a diminishing effect. The fluid temperature decreases with higher Hall current, Casson parameter, and ion slip values but increases due to nonlinear thermal radiation, the temperature ratio parameter, and the Eckert number. Furthermore, the chemical reaction parameter and Schmidt number reduce nanoparticle concentration within the boundary layer, with the Casson parameter amplifying this effect. The study also examines the rates of mass, heat, and momentum transfer near the surface under varying parameter influences, presenting results through comprehensive graphs and tables. To validate the numerical method, a comparative analysis is conducted against previous studies, demonstrating excellent agreement and thus confirming the reliability and accuracy of the computational approach.

Bond performance of marine concrete with nano-particles to steel bars under the action of both Cl− erosion and freeze-thaw cycles

Offshore structures serve in harsh environment here the combined effects of freeze-thaw cycles and Cl− erosion severely degrade the bond performance between steel bars and concrete, significantly reducing the structures' service life. This paper investigates the bond performance of marine concrete with nano-particles to steel bars under the simultaneous influence of Cl− erosion and freeze-thaw cycles. The bond-slip (τ-s) curves are derived from pull-out tests, in order to reveal the mechanism of nano-particles to improve the bond performance of reinforced concrete under the action of both Cl− erosion and freeze-thaw cycles, the microstructure of the bond interface between steel bar and concrete is examined using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and mercury impression test (MIP). The test results show that adding nano-SiO2 and nano-TiO2 enhance the cracking bond strength (τs), ultimate bond strength (τu), ultimate slip value (Su), and residual bond strength (τr) of reinforced concrete. The optimal content for both nano-SiO2 and nano-TiO2 are 2 %, with nano-SiO2 showing superior effect. When Cl− erosion and the number of freeze-thaw cycles are certain (N = 100), the τu values of NSC20 and NTC20 are increased by 26.25 % and 16.68 %, and the Su values are increased by 25.30 % and 22.89 %, respectively, compared with PC. The results of the SEM and EDS analyses indicate that nano-particles promote C–S–H gel formation, reduce porosity and optimize concrete's pore structure, enhance shear strength at the bonding surface, reduce Cl− content at the interface, slow down the corrosion of the steel bars. Thus, the addition of nano-particles significantly improves the bond performance of reinforced concrete under the action of both Cl− erosion and freeze-thaw cycles, which is vital for enhancing the load-bearing capacity and seismic performance of engineering structures.

An investigation to microstructural and texture evolution during the cold rolling of Al0.3CoCrFeNi high entropy alloy

In the present study, Al0.3CoCrFeNi high entropy alloy (HEA) was subjected to thickness reductions through cold rolling process in order to thoroughly investigate the evolution of microstructure and deformation texture. Important aspects of deformed microstructures such as the formation of twinning bundles and shear bands in the specimens were monitored. The evolution of texture during the cold rolling process was measured by X-Ray Diffraction (XRD) and Electron Back Scatter Diffraction (EBSD) technique which revealed the formation of Copper type texture at the initial stages of rolling due to slip deformation mechanism. Originated from twinning and followed by shear banding, the texture was subsequently developed toward predominantly Brass type. Microstructural features and texture evolution behavior of the investigated single phase FCC alloy was attributed to its low SFE level. Visco Plastic Self Consistent (VPSC) technique was coupled in the research to simulate the material behavior and to examine the contribution of slip and twinning systems. Benefiting VPSC justifications, the texture transition from Copper type to Brass type was related to lower CRSS value of slip in comparison to twinning at the small strains which was then grows faster at the later stages of rolling facilitating the onset of twinning and providing the texture transition basement.

Analysis of Bonding Properties of Corroded Reinforcement Concrete

In order to investigate the degradation of bonding properties between corroded steel bars and concrete, this study employs the half-beam method to conduct bond-slip tests between corroded steel bars and concrete after impressed-current accelerated corrosion of the steel bars in concrete. The effects of steel corrosion rate, steel bar diameter, steel bar strength grade, and concrete strength grade on the bonding properties between concrete and corroded steel bars were analyzed. The influence of different corrosion rates on specimens’ bonding strength and bond-slip curves was determined, and a constitutive relationship for bond-slip between corroded steel bars and concrete was proposed. The results indicate that the ultimate bonding strength of corroded reinforced concrete specimens decreases with increasing corrosion rate. Additionally, an increase in corrosive crack width leads to a linear decrease in bonding strength. Evaluating the decline in adhesive properties through rust expansion crack width in engineering applications is feasible. Furthermore, a bond-slip constitutive relationship between corroded steel bars and concrete was established using relative bond stress and relative slip values, which aligned well with the experimental findings.

Seismic Performance of Steel-Reinforced High Strength Concrete Joints Considering Bond Slip Effect

This study presents a solution for push-out failure for the staged bond-slip constitutive relationship between the structural steel and high strength concrete, taking into account the concrete strength grade, anchoring length, and stirrup ratio. The critical point coordinates for different stages are determined by the tests of 14 steel-reinforced high strength concrete (SRHSC) specimens. It is observed that with the increase in the concrete strength grade and anchorage length, the ultimate load of the specimens increased significantly, but the influence on the residual bond strength was not significant. The effect of the stirring ratio was mainly manifested in a slight increase in the initial bond strength. The formula for calculating SRHSC characteristic bond strength and characteristic slip value is established, and the bond-slip constitutive relation of SRHSC is proposed based on the tests. The material constitutive model considering the effect of bond-slip is implanted into the software in the case of the ABAQUS finite element platform. The material is applied to the numerical simulation analysis of the SRHSC exterior joints. The rationality and accuracy of the new material are verified by comparing the simulation results with the test results.

Coseismic slip model of the 14 January 2021 Mw 6.2 Mamuju-Majene earthquake based on static and kinematic GNSS solution

Abstract The Mw 6.2 Mamuju-Majene earthquake occurred on 14 January 2021, with the epicenter at 118.890°E, 2.972°S. The shaking caused severe damage in West Sulawesi, especially in the Mamuju and Majene cities. Most of the coseismic slip distribution of the Mamuju-Majene Earthquake is derived from the daily solutions, which might include early postseismic deformation. Therefore, we conducted a coseismic slip model using kinematic solution based on Global Navigation Satellite System (GNSS) to determine the best coseismic slip values and model distribution. Our analysis indicates that the coseismic displacement from the kinematic solution is higher than the static solution. The GNSS data was utilized for inversion analysis, considering two potential fault sources, they are the Makassar Strait Central Fault and the Mamuju Fault. We found a larger misfit between the observed data and the model generated on static and kinematic solutions along the Makassar Strait Central Fault. Based on the kinematic solution, the coseismic slip distribution represents that fault rupture spreading along a north-south orientation, while the static solution is centered in the northern part. The maximum coseismic slip from each kinematic and static solution is 0.29 m and 0.11 m, respectively. Meanwhile, the seismic moment generated from the kinematic solution is 1.5 × 1026 N m (equivalent to Mw 6.75), which is greater than the static solution of 2.4 × 1025 N m (equivalent to Mw 6.22).

Modeling and adaptive neuro-fuzzy inference system control of quarter electric vehicle

Electric vehicles (EVs) have gained importance in recent years, prompting the development of several control systems to improve their efficiency and performance. In this work, a quarter electric vehicle (QEV) was controlled using a conventional proportional integral derivative (PID) and fuzzy controller to examine and compare with the response of the adaptive neuro-fuzzy inference system (ANFIS) controller. The response of the ANFIS controller was evaluated using MATLAB/Simulink according to different parameters and compared with those of other controllers. In addition, the simulation was based on different driving conditions such as the acceleration and deceleration modes and the type of road: wet and dry. The simulations were carried out on a longitudinal electric vehicle model based on a brushless DC motor, including the Pacejka tire model. The results showed that the ANFIS controller outperformed the PID and fuzzy logic controllers, providing superior dynamic responsiveness and stability when the ANFIS controller smoothly followed the input speed and the longitudinal slip value reached 3%.

Bonding properties of composite interface composed of concrete/magnesium phosphate cement-based ECC/CFRP plate

To prevent premature debonding of fiber reinforced polymer (FRP) from concrete surface and achieve rapid repair of flexural members, magnesium phosphate cement-based ECC (MPC-ECC) with many advantages of early strength, multi-cracking and steady-state cracking was combined with carbon fiber reinforced polymer (CFRP) to explore the feasibility of strengthening flexural members. The bonding properties of the concrete/MPC-ECC/CFRP composite interface were investigated in this study. Results showed that the higher composite interface bearing capacity can be obtained by using the MPC-ECC as a binder compared to the use of epoxy resin adhesive, which can reach 15.9 kN. In addition, it was found that a good bonding between the high-pressure water gun treated concrete and the MPC-ECC was obtained, which could ensure that the concrete/MPC-ECC interface does not fail before the MPC-ECC/CFRP interface fails. Compared with the concrete/CFRP interface, the maximum effective bond length, slip value of CFRP, and energy consumption of the concrete/MPC-ECC/CFRP composite interface are greatly improved, all of which increase with the increase of MPC-ECC thickness. Furthermore, the composite interface has obvious residual stress in the failure stage, which can avoid the sudden failure of specimens. However, the increase of curing age from 7 days to 28 days does not significantly improve the bonding performance, which reflects that the bond strength of the composite interface mainly develops within 7 days, that is, possessing good early strength characteristics.

Optimising Plate Thickness in Interlocking Inter-Module Connections for Modular Steel Buildings: A Finite Element and Random Forest Approach

Interlocking Inter-Module Connections (IMCs) in Modular Steel Buildings (MSBs) have garnered significant interest from researchers. Despite this, the optimisation of plate thicknesses in such structures has yet to be extensively explored in the existing literature. Therefore, this paper focuses on optimising the thickness of interlocking IMCs in MSBs by leveraging established experimental and numerical simulation methodologies. The study developed various numerical models for IMCs with plate thicknesses of 4 mm, 6 mm, 10 mm, and 12 mm, all subjected to compression loading conditions. The novelty of this study lies in its comprehensive parametric analysis, which evaluates the slip prediction model. A random forest regression model, trained using the ‘TreeBagger’ function, was also implemented to predict slip values based on applied force. Sensitivity analysis and comparisons with alternative methods underscored the reliability and applicability of the findings. The results indicate that a plate thickness of 11.03 mm is optimal for interlocking IMCs in MSBs, achieving up to 8.08% in material cost reductions while increasing deformation resistance by up to 50.75%. The ‘TreeBagger’ random forest regression significantly enhanced slip prediction accuracy by up to 7% at higher force levels.

Numerical solutions for magneto-convective boundary layer slip flow from a nonlinear stretching sheet with wall transpiration and thermal radiation effects

A mathematical model is presented for magnetohydrodynamic viscous incompressible flow of an electrically conducting Newtonian polymeric fluid from a moving permeable horizontal stretching sheet with variable magnetic field, momentum and thermal slip boundary conditions. The emerging nonlinear ordinary differential boundary value problem is solved numerically by the Runge-Kutta-Fehlberg fourth-fifth order numerical method in Maple symbolic software. The effects of the governing parameters on the dimensionless stream function, dimensionless flow velocity and the dimensionless temperature have been investigated, displayed graphically and discussed. It is found that greater momentum slip and magnetic field parameters reduce the dimensionless velocity. It is further observed that higher values of Prandtl number, thermal slip, and conductionradiation parameter (weaker radiation contribution) reduce the dimensionless temperature whilst stronger magnetic field increases the temperature due to the supplementary work expended in dragging the polymer against the action of the magnetic field which is dissipated as heat. Comparisons of numerical results with previous published results show an excellent agreement. The study finds applications in electro-conductive polymer (ECP) processing systems.

Experimental study on bond performance between vertical deformed steel bar and modern rammed earth based on in-situ pull-out test

This study investigates the bond strength–slip behavior between vertical deformed steel bar and modern rammed earth in modern rammed earth wall. Firstly, in-situ pull-out tests were conducted on seven modern rammed earth walls, taking into account the effects of the relative anchorage length of steel bars, the cube compressive strength of modern rammed earth, and the diameter of steel bars on the bond strength and slip of vertical deformed steel bars and modern rammed earth. The experimental results indicate that the bond force–slip behavior between vertical deformed steel bars and modern rammed earth can be divided into four stages: elastic bonding stage, nonlinear rising stage, nonlinear decreasing stage, and residual stage. Based on the experimental results, six characteristic values were defined: ultimate bond strength τu, cracking bond strength τs, residual bonding strength τr, ultimate bond slip Su, cracking bond slip Ss, residual bond slip Sr. An average bond strength-slip constitutive model for vertical deformed steel bars and modern rammed earth was proposed. The model was compared with the experimental results and can be used to predict τu, τs, Su, Ss. Due to the anisotropic characteristics of modern rammed earth, there will be a large deviation in the prediction of τr and Sr. There are three types of failure in the pull-out specimens, namely, pull-out failure, splitting failure and conical failure. The relative anchorage length of steel bar, the cube compressive strength of modern rammed earth and the diameter of steel bar have different degrees of improvement on τu, τs, but have little effect on τr. Due to the brittle failure of modern rammed earth specimens, the above three factors have little effect on the slip value.

Semianalytical modeling of squirrel-cage induction machines with consideration of iron permeability and eddy-currents using elementary subdomain technique

PurposeThis paper aims to propose a semianalytical model of a squirrel-cage induction machine (SCIM), considering local magnetic saturation and eddy-currents induced in the rotor bars.Design/methodology/approachThe regions of the rotor and stator are divided into elementary subdomains (E-SDs) characterized by general solutions at the first harmonic of the magneto-harmonic Maxwell’s equations. These E-SDs are connected in both directions (i.e., along the r- and θ-edges).FindingsThe calculation of the magnetic field has been validated for various values of slip and iron permeability. All electromagnetic quantities were compared with those obtained using a two-dimensional finite-element method. The semianalytical results are satisfactory compared with the numerical results, considering both the amplitude and waveform.Originality/valueExpansion of the recent analytical model (E-SD technique) for the full prediction of the magnetic field in SCIMs, considering the local saturation effect and the eddy-currents induced in the rotor bars.

Behavior of FRP-engineered cementitious composite layer and concrete interface with FRP anchors

The problem of low material utilization caused by premature interface debonding is prevalent in carbon fiber-reinforced polymer (CFRP)-reinforced concrete structures. In this study, the influence of anchors on the bonding and behavior of the FRP-engineered cementitious composite (ECC) layer and concrete interface was analyzed. A total of 42 single shear tests were performed to investigate the interface–bond behavior between the FRP-ECC layer and concrete under static load in case of anchor reinforcement. The variables mainly include the matrix type, anchor location, anchor spacing, and number of anchors. The results show that the anchor can increase the interfacial load-carrying capacity up to 85%; the maximum slip value of the interface can also be enhanced. Furthermore, the influence of the location, spacing, and number of anchors on the interface bonding performance is closely related to the effective bonding length and post-anchor bond length. The effective bonding length is 400 mm based on the strain distribution calculation and analysis. The test results provide valuable information for FRP anchor reinforcement in FRP-ECC composite layer-reinforced concrete structures.