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In the past few years, new techniques have emerged using steel plates instead of traditional reinforcement in the reinforced concrete beams. This study deals with using a new method for reinforced concrete beams using steel plates instead of traditional steel bars with different thicknesses of (4, 5, and 6 mm) placed vertically inside the lower part of the beam. Four reinforced concrete beams were cast and tested under a two-point load. All beams had the same cross-sectional area of reinforcement and dimensions of 2100 mm in length, 350 mm in height, and 250 in width. The results showed that as the thickness of the steel plate increases, the samples would have greater resistance until more deflection is produced. In addition, there is a reduction in the crack load, ultimate load, and yield load when replacing reinforcing bars with steel plates. In which, a reduction in crack load by about 11.1, 15.5, and 22.2% plate thicknesses of 4,5,6 mm respectively, compared to reference beam that had a deformed steel bar (Dia. 16 mm). In addition, a reduction in yielding load was observed about 42, 53, and 60% for steel plate thickness of 4, 5, and 6 mm respectively, compared to the reference model. Finally, the cracks for all the steel plate specimens compared to reference specimens were wider and smaller.

The article proposes a structural solution for the base of a wooden frame column on flat links glued in the support part of the column – steel plates welded to the base plate. The results of numerical studies of the column, taking into account the parameters of the adhesive connection of the plates with wood and the anisotropy of wood, are presented. The column model takes into account the geometric and physico-mechanical characteristics of wood, steel plate bonds and adhesive compound. The main results of numerical studies are verified with the results of the analytical calculation of the column performed by the method of initial parameters. A physical model with the proposed structural solution of the column base was made and tested. The numerical and analytical calculations of the column were validated, and the main conclusions of the experimental and theoretical study were presented.

This paper reports on the results of a numerical study to simulate the response of carbon fibre reinforced polymer (CFRP) retrofitted steel plates to applied blast loads using finite element software, LS-DYNA. The results of the simulation were validated against plate response and magnitude of deformation obtained from previous experiments. The uniform blast load was generated in the experiment by detonating a cylindrical charge down the end of a square tube. The finite element code LS-DYNA was used to simulate the structural response of the respective blast structures. For the numerical model, the blast load was simulated using the mapping feature available in LS-DYNA for the multi-material arbitrary Lagrangian-Eulerian (MM-ALE) elements which significantly reduced the size of the air domain in the model. The simulations showed a satisfactory correlation with the experiments for the blast results and post-failure deformations that occurred in CFRP retrofitted steel plates.

The presented study describes a diagram of an eddy-current measuring system built on the basis of a subminiature eddy-current converter, intended for the conducting materials’ study. The article describes the results of testing a designed measuring system for defects search in 6XB2S steel samples, connected by a weld joint. The technology for creating such materials permits the significant impact resistance of finished products and provides an optimal combination of hardness and toughness. However, the defects formed in the material near the weld joint become a serious problem in the operation of such materials. In this study, an assessment of the possibility of searching for model defects hidden by a weld in two steel plates was made. The defects had different linear dimensions (0.3 - 0.9 mm) and occurred at different depths (1 - 2 mm). The developed system showed high efficiency of scanning and searching for defects with linear dimensions up to 0.9 mm. The search for smaller defects required a significant modernization of the developed measuring system - the introduction of a second eddy-current converter. The article presents the data confirming the feasibility of this change in the measuring system and the possibility of using a measuring system with two eddy current converters to search for small defects occurring at a considerable depth.

In recent years, geopolymers have gained a wide attention as highly ecological-friendly building materials, having a capability to cut down 70% of CO2 emissions in comparison to the ordinary cement concrete. In this study, geopolymer mortars are proposed as repair materials for reinforced concrete structures, due to their superior acid resistance, heat resistance and high strength in comparison to the existing repair materials. The objective of this study is to investigate the adhesion properties of geopolymer mortars to concrete substrates with different surface treatments, steel plates and rebars. As a result, the geopolymer mortars are found to have excellent adhesion properties to dry concrete substrates, steel plates and rebars. Concrete substrates treated with grinder, further enhanced the adhesion properties of geopolymer mortars. On the other hand, poor adhesion of geopolymer mortars to wet concrete substrates was observed due to the presence of water on the interfacial zone, which decreased the alkali concentration of the geopolymer, resulting in lower adhesion strength. In general, geopolymer mortars are found to have suitable adhesion properties to the concrete substrates, steel plates and rebars and can be applied as repair materials for reinforced concrete structures.

Cellular steel beam is flanged steel beam with circular openings of uniform diameter and distance between each opening. The main benefit of such beam is to reduce the structural weight without reducing the strength significantly. A rectangular steel plate with circular opening is frequently used as a model of a web panel of such beam with vertical web stiffeners. The dimension of the plate is the dimension of the web bounded by top and bottom flanges and two adjacent vertical stiffeners. In this research, finite element method is utilized to perform inelastic buckling analyses of rectangular steel plates with circular openings under shear forces along all four edges assuming steel as elastic-perfectly-plastic material with yield stress of 250 MPa. Both nonlinear geometry and nonlinear material are considered in the analyses. The objective of this research is to study buckling behavior of the plate in terms of buckling mode, critical load, and Von Mises (effective) stress distribution. The buckling shear loads of the plates of various length-to-width ratios of the plate (1.0, 1.25, and 1.50) and various opening-diameter-to-plate-width ratios (0.00, 0.05, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, 0.45, 0.50) have been obtained from the analyses. The deformation and Von Mises stress distribution at every load level have been obtained as well from the finite element analyses. Equation to predict inelastic buckling shear force of a rectangular steel plates with circular opening under shear forces is proposed in this study. Verification of the method has been performed by comparing shear buckling loads resulted from finite element analyses with the analytical results in the elastic range.

Adhesively bonded joints are widely used in many branches of industry. Mechanical degradation of this type of connections does not have significant symptoms that can be noticed during visual assessment, so non-destructive testing becomes a very important issue. The paper deals with experimental investigations of adhesively bonded steel plates with different defects. Five samples (an intact one and four with damages in the form of partial debonding) were prepared. The inspection was conducted with the use of guided wave propagation method. Lamb waves were excited at one point of the sample, whereas the out-of-plane velocity signals were recorded in a number of points spread over the area of overlap. The processing of signals consisted of calculations of weighted root mean square (WRMS). The results of the analysis showed that the WRMS maps allow for identification and determination of size and shape of debonding areas.

This work presents ongoing research on the influence of fluidstructure interaction (FSI) effects on the ductile crack growth in perforated steel plates subjected to blast loading. The FSI effects were studied numerically by comparing the predictions from an uncoupled and a coupled FSI approach. Experimental results were used to evaluate the reliability of the numerical simulation. It was found that the numerical models were able to predict both crack initiation and crack growth in the plate, however, some distinct differences were also observed in the performance of the two approaches under consideration. The most important feature in predicting the observed fracture patterns was an accurate description of the blast loading during the FSI.

Aiming at the high internal and external water pressure tunnels built in unfavorable geological bodies, this study proposes a novel type of composite support structure in which steel plates are poured inside concrete linings. Compared with traditional structures, it has the advantages of higher tensile strength, better crack resistance, and impermeability. Taking the diversion tunnel of a hydropower station as an example, based on linear and non-linear finite element simulations, mechanical properties of the steelconcrete composite lining structure for a hydraulic tunnel in soft surrounding rocks are analyzed. On this basis, the concrete crack control under this supporting condition is verified. Research results can provide a reference for the selection of reasonable steel plate thicknesses and reinforcement types in design.

Experimental and numerical investigations are carried out to determine how thin steel plates with pre-cut defects behave under blast loading. The defects considered in this study are represented by four square holes, symmetrically distributed around the centre of the target plates. The target plates were manufactured from two types of steel, i.e., a dual-phase medium strength steel and a high-strength martensitic steel. A shock tube facility was used to expose the plates to blast-like loading conditions. The experiments showed that both the blast resistance and the corresponding fracture mode changed with material properties. Numerical simulations were performed using the finite element code LS-DYNA, where the numerical results were found to be in good agreement with the experimental data in predicting the ductile fracture during the blast-structure interaction. The numerical simulations confirmed that significant work hardening will distribute the plasticity throughout the plate material during deformation, while limited work hardening will tend to localize the plasticity that results in earlier fracture.

The article presents the results of full-scale comparative tests of various protective compositions, for which the Movil car preservative, Litol-24 grease, PVC grease, K-17 preservation oil, experimental preservation compound (EKS-1) were used. The objects of conservation are steel plates of grades U8, 65G, 45, 40X, and St3. After the tests, etching, weighing, measuring the surface roughness of the samples were performed, and metal losses were determined. Tests of EKS-1 show protective efficacy comparable to that of greases, and in some cases, it significantly exceeds it. It is proved that the area of corrosion and metal loss during the test of the composition on these materials was not more than 4.7 % and 5.3 g/m2 per year, respectively. The research results show that the use of the protective composition EKS-1, due to its manufacturability, significantly reduces the complexity of work during the conservation of agricultural machinery, as well as ensures the protection of metal products during both short-term and long-term storage.

As early as 1974 the British Hydrodynamic Research Association, BHRA, held the First International Conference on Cutting by Water Jets. The subject was at its early stages. Since then a large amount of research work has been carried out and the process has been greatly developed. In this paper, utilization of water jets for flexible cutting parts of intricate shapes in steel plates and granite is presented and discussed.

Many reinforced concrete beams have been found deficiencies in shear due to lack of shear reinforcement. Few researches have been done to investigate shear strengthening of low concrete strength of RC beams using bolted steel plates. This paper presents experimental results on the behaviour of RC beams strengthening using full steel plates along the shear span fixed with bolts. Nine RC beams having dimension of 150x200x1500mm were tested to failure on simply supports with four point loadings setup. The beams were reinforced with tension rebars area of 289.8 mm2 (2D10+1D13) and transvers reinforcement of Ø6-125. Two dial gauges were installed at the beam middle span to measure beam deflection during the test. The results show that the applications of steel plate and bolts as external reinforcement increase beam shear capacity, stiffness and delay the occurrence of first diagonal cracks. Beams stregnthened with U-shape plates gave better performances than the beams with two pieces of L-shape plates due to better achorages.

The developments of plates are strongly driven by demands from high-sophisticated pipeline and structural applications. Such needs reflect in plates with higher thickness, larger width, higher toughness also at lower temperatures, higher strength and/or better resistance to sour environments. The requirement profiles are, in some cases, exceptional and have become achievable, in an extreme combination of alloying and processing technologies, only as a result of comprehensive development work and plant investments. A broad potential for innovation derives by the utilization of the key-technology TMCP (Thermo-Mechanical Controlled Process). The status of present-day heavy plate production will be presented. An outline of the production facilities, routes and process variants will be given. As a central element to achieve high-class requirements, aspects and parameters of the metallurgical design will be explained. The utilization will be explained and illustrated with selected recent applications.

This research offers experimental and numerical study for the ultimate strength analysis and post buckling behaviour of plate girders subjected to shear and bending stresses. Two Plate girders of length 2.5m are designed consisting from three separate structural steel plates welded together to form I - section. The dimensions of the first girder section is 512 mm × 120 mm while the second girder section is 412mm × 120 mm. Mechanical properties for plate girders components were found by testing three samples of each plate. The ultimate shear strength was found by examining two plate girders in the laboratory under concentrated load applied at the middle span. A numerical study of the tested plate girders was carried out by using the software program (ANSYS) to study the behaviour of girders steel under the influence of loads application. The results showed that the ratio of the experimental ultimate load strength to the numerical ultimate load strength is 97% 94% for plate girders 1 and 2 , respectively. For the part of using theoretical study. The results obtained from the equations , it was observed that the ratio of the experimental ultimate load strength to the theoretical ultimate load strength is 83% for plate girders1 and 90% for the plate girder 2.Through comparison between experimental, numerical and theoretical results it was observed good andacceptable agreement. Thus confirming the accuracy of the modelling between this methods and obtain convergent results in all cases. Also it was found when an increase in the depth of the web has effect in increasing the ultimate shear strength for plate girder by about 19%.

In order to increase their production of steel plates to 7.5 million tons/year, ArcelorMittal Tubarao faced the challenge to increase sinter plant productivity from 34.00 t/d/m 2 to 42.00 t/d/m 2 . This was achieved in June 2006 through three main actuators: raw materials, stabilization and optimization of the current equipment and implementation of new technologies.

An experimental investigation was undertaken in order to study the behaviour of laminated fabric and steel plates when subjected to impulsive load and fragment impact. Fully clamped rectangular plates were loaded by the blast wave generated due to explosion of TNT charges and by a steel fragment accelerated by the explosion products. The velocities of steel fragments and blast wave impulses were estimated experimentally and theoretically.

Capacity of the ladles is in way to be increased in several steelplants for flat carbon steel products (Dunkirk, Florange). The new steel ladles have been designed, taking into account several key points: the stiffness and the service temperature of the steel shell, which is controlled by the geometry of shell reinforcements and by the efficiency of the thermal insulation layer; the stiffness of the lip-rings, which can be greatly improved by using steel plates protected by refractory concrete; the wear of the slag line in MgO-C bricks, which can limit the ladle campaign if vacuum tank degassing process is used for ULC steels production. Slag control is required. Numerous trials are also in way to limit the wear of the bottom impact zone of the steel ladle, including pre-shaped alumina-spinel cast bottom, in Arcelor Dunkirk.

The heavy steel plates (100 - 300 mm) require a good geometric stability during the manufacturing operations by end users. This stability depends on the residual stress state inherited from the manufacturing process. This residual stress state is assessed by an ultrasonic testing method : the acoustical birefringence. The first tests carried out on representative heavy plates allowed to define the most suitable measurement configurations and to identify the residual stress states that could generate shape defects. Then, this method was applied to industrial heavy plates with success.

The present investigation is concerned with the impact of thin steel plates used in shipbuilding. The problem is studied numerically with the commercial code LS-DYNA and experimentally with an apparatus propelling a 200g projectile up to 30m/s with a crossbow. The clamped sample of sheet metal is rectangular (250 mm wide; 20 mm width and 4 mm thick), in common shipbuilding material with a 360MPa elastic limit. Impact takes place at the center of the sample. Moreover, an initial tensile stress can be applied to the plate, up to 300 MPa. The aim of this study is first to illustrate the influences of the boundary conditions and the initial tensile stress value on the deflection of the central point of the plate. The second part is concerned with wave propagation. The objective is to explain analytically the dispersive form of the measured strains at different locations and to establish the relationship between the flexural waves and the observed losses of contact.

An analytical prediction on flexural response of reinforced concrete (RC) beams strengthened with steel plates is presented in this paper. The method used in this study is based on theoretical moment-curvature determination which able to determine the complete response of reinforced concrete cross section subjected to monotonic flexural load. A computer program named Reinforced Concrete Cross Section Analysis (RCCSA) was developed and utilized to facilitate the computation process. Two types of flexural strengthening (tension-face and web bonded steel plates) were analyzed using the software and then compared with the experimental result. Result validation using existing available software was also carried out using Respone-2000 software. The comparison shows that the analytical model can be used to predict the flexural response of strengthened reinforced concrete cross section with a good accuracy.

Data examination regarding historical earthquakes in Indonesia has revealed that damages occurred mostly in non-engineered buildings. Many non-engineered buildings have serious design and construction deficiencies in using concrete of inadequate quality and have poor steel reinforcement detailing especially in their beam-column joints. These joints require an effective strengthening technique which is simple to install. This paper presents steel plates to reinforce concrete beam-column joints through numerical studies. The finite element model was developed using ABAQUS. The FEM results were validated by comparisons with previous experimental tests. For this purpose, two RC beam-column joints were analyzed, including original standard beam columns and non-standard steel detailing strengthened with steel plates. The comparison of the results from numerical model indicated that steel plates could increase lateral strength, ductility, energy dissipation and increase the shear strength of the joints.

The aim of the study is to validate the Lemaitre Chaboche damage model in the explicit finite element code EUROPLEXUS. Tensile tests have been performed on smooth and notched specimens of 304L type stainless steel to determine Lemaitre and Chaboche damage model's parameters at strain rates from quasi-static to 150 s -1 with different triaxiality ratios. The procedure of parameter's identification is based on finite element calculations. The damage parameters are identified through the experimental measurements. We present the results of an experimental investigation of the impact resistance of Inox 304L plates and compare these results with numerical simulations. The goal of the study is to determine the magnitude order of the perforation energy.

With the present laser technology, laser beam welding becomes attractive for relatively thick products. In order to improve the knowledge about the properties of the welded joints, tests have been carried out with different grades and thicknesses of steel plates. Strength, toughness and fatigue properties are found to be quite satisfactory, but further progress on weld quality and safety should be made.

This study is concerned with the development of a fracture criterion for the impact fracture of jointed steel plates of a bolted joint used in a car body. For the accurate prediction of crash characteristics of car bodies by computer-aided engineering (CAE), it is also necessary to examine the behavior and fracture of jointed steel plates subjected to impact loads. Although the actual impact fracture of jointed steel plates of a bolted joint used in cars is complicated, for simplifying the problem it might be classified into the shear fracture and the extractive fracture of jointed steel plates. Attention is given to the extractive fracture of jointed steel plates in this study. The extractive behavior and fracture of three kinds of steel plates used for cars are examined in experiments and numerical simulations. The impact extraction test of steel plates jointed by a bolt is performed using the one-bar method, together with the static test. In order to understand the mechanism of extractive fracture process of jointed steel plates, numerical simulations by a FEM code LS-DYNA are also carried out. The obtained results suggest that a stress-based fracture criterion may be developed for the impact extractive fracture of jointed steel plates of a bolted joint used in a car body.

To optimize continuous casting process of heavy steel plates at Sollac-Dunkerque, a metallurgical study of the effect of electromagnetic stirring, in the secondary cooling zone, was carried out. It was shown that stirring increases intergranular segregation around equiaxed crystals. Based on these metallurgical results, a physical model of equiaxed dendritic growth was developed. The specific feature of this solidification model is to take into account the effect of crystals morphology on intergranular segregation. Calculations were performed for an alloy Fe - 1.5 % Mn at different cooling rates in a range of 0.02 to 0.5 °C/s. Typical cooling curves with recalescence were obtained for equiaxed solidification. A mathematical simulation to analyse the effect of stirring on equiaxed growth has also been made.

This paper experimentally investigates drag reduction, durability for operations and effects for preventing microorganism from adhering to the surface when the superhydrophobic coating is applied on a solid surface. The experiments are divided into two parts. In the first part, a pipe flow system was established to measure the drag and to test the durability of the micro-structure of superhydrophobic coating at average speeds varying from 1m/sec to 6m/sec. In the second part, we tested the effect for preventing microorganism from adhering to the surface by putting the coated steel plates into sea water. There are four different superhydrophobic coatings in the present study. The experimental results were compared to those applied by ship paint usually used at CSBC.

Electrochemical impedance measurements were archieved on coated steel plates. The organic was scratched and the plate was polarised under cathodic protection. The impedance measurements allowed us to detect the cathodic disbonding of the coating. In some cases, the “high frequency” (104-10 Hz) part of the Nyquist impedance plot was a straight line, with a slope equal to 1 ; this indicates the infiltration of a thin layer of electrolyte between the coating and the steel plate.Howewer, a quantitative study of the cathodic disbonding mechanism (rate, extent) is not yet possible, from experimental impedance plots ; calibration experiments are required because the real structure and geometry of the thin layer are complicated and cannot be described by the other-simple assumptions of the existing models.