Support Plate Research Articles

Selected aspects of the design and construction of reinforced concrete sunk wells

The article provides basic information on the design and construction of sunk wells. Sunk wells are enginee-ring structures commonly used in construction, particularly under difficult soil conditions or when construction sites have a small area. Sunk wells are made using the “cut and lower” method, which means that the first segment to be lowered is equipped with a cutting-edge section (bottom blade) that cuts into the soil and the structure sinks into it. In design, it is necessary to take into account the phased execution of these structures and their spatial work. The article presents the loads working during the construction and operation of sunk wells, as well as the assumptions and guidelines for static calculations and dimensioning. When the sunk well steining is significantly high (the well is embedded deep), concreting and lowering are most often performed in two or three segments. The article describes the subsequent steps taken during the implementation of sunk wells, constantly changing static diagrams and the method of adopting them in calculations. It also presents the method of lowering sunk wells with possible implementation difficulties. The article is supplemented with exemplary drawings of the steining reinforcement, cutting-edge section and bottom plate of the well and the photos of selected realizations.

Practical temperature calculation and fire-resistant design of special-shaped concrete-filled steel tubular columns

The fire performance of special-shaped concrete-filled steel tubular (SCFST) columns under axial load was investigated in this paper. The ABAQUS based finite element models were conducted for heat transfer and structural analysis. Twelve fire tests on SCFST columns under the ISO-834 standard fire curve by the authors' research were used to verify the model. In addition, heat transfer and fire-resistant mechanism of full-scale SCFST columns were studied; and extensive parametric studies were investigated to examine the influence of fire protection layer thickness, column limb thickness, slenderness ratio and other factors on temperature distribution and fire behavior of SCFST columns. Through the calculation and analysis of temperature field and fire resistance, a simplified temperature calculation method for steel tube, tension reinforcement, and inner steel plate are proposed along with the modularization temperature calculation method for special-shaped concrete sections. Moreover, the ultimate bearing capacity calculation method for SCFST columns under the standard temperature rise curve is proposed allowing for the influence of high temperatures on material properties, which can also be applied to determine fire resistance of SCFST column. Finally, the calculation method for the thickness of fire protection layer and the corresponding fire design is proposed based on the delaying temperature mechanism.

Slurry Discharge Pipeline Damage and Wear Due to Transporting Rock Particles during Slurry Shield Tunneling: A Case Study Based on In Situ Observed Results

Rock particles in excavated materials can damage and wear down slurry discharge pipelines when slurry shield tunneling occurs in a pebble layer and rock ground. This pipeline damage and wear, if not properly dealt with, can lead to a broken-down tunneling machine. Based on a slurry shield tunneling project in China, damage and wear were thoroughly examined. The observed pipeline wear and leaks, transported rock particles, mechanical properties, and flow rate of the carrier slurry were presented. The measured results showed that the wear rates of a straight pipe, a pipe along a curved tunnel, a 60° inclined pipe, and a 90° elbow pipe in pebble ground were approximately 0.71 mm/100 rings, 1 mm/100 rings, 2.14 mm/100 rings, and 4 mm/100 rings, respectively. When the machine drove into rock ground, the wear rates increased by one to two times, which could be attributed to the sharper particle shapes. Countermeasures to address these issues, such as adjusting the pipeline layout, welding reinforcement plates in advance, and preparing additional pipes, were highlighted. The wear rates of different types of pipes, the effectiveness of new pipeline fixing methods, and the probability of pipeline leaks in different strata were discussed in detail.

Research on strain testing technology of electromagnetic railgun’s abnormal barrel

Aiming at difficult strain test and unable to accurate strain test for electromagnetic railgun’s special-shaped barrel bore, the strain testing technology of special-shaped barrel was studied. According to electromagnetic railgun strain test characteristics analysis, the back of the rail and the back of insulation support plate are selected as the strain test points, FBG(Fiber Bragg Grating) stain sensor is embedded along the circumference of the barrel to obtain the special-shaped barrel true stain value. At the same time, in order to comparison, The papers studies the rail’s strain simulation technology for electromagnetic railgun, the simulation result is accordance with strain test result, show that stain measurement method is feasible, and measurement results is reliable. The research results can provide data support for location to position of projectile in the special-shaped barrel bore by strain feature.

Comparison of Melted Corium Relocation during Severe Accident of High Temperature Reactor using Moving Particle Semi-Implicit Method

System failure in nuclear reactors can cause degradation of a reactor core, allowing melting and relocation of the corium to the lower plenum in the nuclear reactor system. In this study, a severe accident simulation was carried out using the Moving Particle Semi-Implicit (MPS) method. In this method, we model the relocation of molten corium on the reactor core (support plate) to the lower plenum for several conditions with variations: corium material, lower plenum conditions, temperature, viscosity, and density. Those treatments were carried out in order to be able to compare and analyze the characteristics of the corium melt by reviewing the velocity profiles. The formation of a corium pool and debris bed can result in significant temperature differences and high heat flux against the walls of the reactor vessel, causing a decrease in the integrity of the reactor vessel and reactor failure.Keywords: Corium, Uranium Dioxide (UO2), Zirconium Dioxide (ZrO2), Fluid Relocation, Moving Particle Semi-Implicit (MPS).

Improving the Predictivity of a Steam Generator Clogging Numerical Model by Global Sensitivity Analysis and Bayesian Calibration Techniques

In pressurized nuclear reactors, steam generators are massive tubular heat exchangers transferring heat from the primary to the secondary fluid to produce the steam needed by the turbines. After several years of operation, because of deposit, their tube support plates (TSPs) can undergo clogging that may cause important economic and safety issues in case of nonpreventive actions. To understand and predict this phenomenon, several nondestructive examinations can generally be gathered at various times during the heat exchanger operation. A numerical mechanistic model has been recently developed and implemented in a dedicated computer code. The objective of this work is to improve the modeling of the clogging phenomenon to increase the predictive capability of the computer code. A global sensitivity analysis, based on Sobol’ indices, is first performed by the use of a metamodel that is learned on several runs of the computer code. Such an analysis, cast under a physical perspective, helps the identification of the most influential physical parameters and paves the way to a better understanding of TSP clogging. A Bayesian calibration of an epistemic calibration model parameter is then applied to fit the simulation results to experimental data. The additional information coming from the experimental data is then transferred to the calibration parameter with a mathematical model (artificial neural network). The resulting hybrid model thus compensates some lacks of the initial physical model on the considered data set.

Experimental evaluation of the size and distribution of lateral pressure on the walls of the excavation support

The paper presents the results of a research experiment that aimed at verifying the size and distribution of earth pressure acting on the excavation support with reference to commonly used theoretical solutions. The tests were carried out on the object in its full scale. For this purpose, a 6 m deep excavation was made in the testing ground. It was secured with a support system i.e., a point chamber consisting of corner columns and a system of three rows of fin plates. The tests relied on various measurement techniques. The earth pressure was measured with sensors specially designed and manufactured for this research experiment. Simultaneously with earth pressure measurements, there were measured stresses in the support plates with the use of strain gauges and deflections using laser scanning and a calibrated measurement patch. The tests were conducted for three months, with different backfill load. The measured values of earth pressure increased in a manner similar to the values of hydrostatic thrust, reaching max. 30 kPa before making the excavation and 25 kPa after making the excavation and assembling the support. The results were consistent with the values determined in line with commonly used theoretical solutions. The stresses caused a 15 mm deflection in the plates. Backfill load significantly affected the value of thrust down to a depth of approx. 4 m but did not cause a further increase in the deflection in the plates.

Design and Experimentation of a Residual-Input Tube-End Cutting System for Plasma Bags Based on Machine Vision

In response to the lack of plasma bag-breaking equipment and time-consuming manual recovery of plasma in China, this study focuses on the distal end cutting of a plasma bag residual-input tube and designs a machine-vision-based plasma bag residual-input tube cutting system. The system comprises a plasma bag rotation device, a bottom disc, an image acquisition device, a cutting device, and a device control system. The image acquisition device captures images of the rotating plasma bag and calculates the Euclidean distance from the end of the plasma bag input-tube distal end to the outer edge of the bottom support plate and the distance from the input-tube distal end to the centerline of the plasma bag. Two distinct value acquisition algorithms are designed for the two types of input tubes. The screw slide moves accordingly. When the plasma bag is above the cutting part, the cutting part cuts the end of the residual-input tube of the plasma bag. The prototype performance tests reveal that the cutting error is within 10% of the end of the plasma bag input tube distal end, the cutting success rate is 100%, and the processing time for each bag is 2.5 s, which meets the time requirements of the plasma bag breaker.

Comparison of different reinforcement methods on crack monitoring characteristics of eddy current array sensor

PurposeThis paper aims to study the influence of different reinforcement methods on crack monitoring characteristics of eddy current array sensors, and the sensors with two different reinforcement methods, SUS304 reinforcement and permalloy reinforcement, are proposed.Design/methodology/approachFirst, the finite element model of the sensor is established to analyze the influence of the reinforcement plate’s electromagnetic parameters on the crack identification sensitivity. Then, the crack monitoring accuracy test of sensors with two reinforcement methods is carried out. Finally, the fatigue crack monitoring experiments with bolt tightening torques of 45 and 63 N · m are carried out, respectively.FindingsIn this study, it is found that the crack identification sensitivity of the sensor can be improved by increasing the relative permeability of the reinforcement plate. The crack monitoring accuracy of the sensors with two different reinforcement methods is about 1 mm. And the crack identification sensitivity of the sensor reinforced by permalloy reinforcement plate is significantly higher than that of the sensor reinforced by SUS304 reinforcement plate.Originality/valueThe sensor reinforced by reinforcement plate can work normally under the squeezing action of the bolt, and the crack monitoring sensitivity of the sensor can be significantly improved by using the reinforcement plate with high relative permeability.

Analysis and Predictive Evaluation of Mechanical Properties of Steel Anchor Box for High-Speed-Railway Cable-Stayed Bridge

As the stress amplitude in the anchorage zone of cable-stayed bridges vary considerably, it is essential to study the fatigue-load-bearing capacity of the anchorage structures of cable-stayed-bridge girders. In this study, the mechanical properties and force-transmission mechanism of a built-in double-fixed steel anchor box, as well as the influence of the geometric design parameters of the main pressure plates and support plates on its stress performance, were studied. A PSO-BP built-in double-fixed steel anchor box mechanical-performance-prediction-and-evaluation system was established, with the geometric design parameters of the important plates of the main body of the anchor box as the input variables and the mechanical properties of the main stress-transmitting welds of the steel anchor box as the output-evaluation variables. The results were as follows: the cable force was mainly transmitted in the form of shear force through the welds between the support plate and the web of the main beam; the transmission ratio of the four main welds was generally maintained at about 23%, and the stress distribution of each plate was relatively uniform, with most of the stresses in the range of 10~50 MPa. The shear-stress-inhomogeneity coefficient of the transmission weld was sensitive to the changes in the thickness of the support plate and the pressure plate, and the transmission ratio of the main weld was sensitive to the changes in the thickness and length of the support plate. The PSO-BP-based mechanical-performance-prediction-and-evaluation system can be used to explore the intrinsic relationship between the designed cable force, important plate-geometry parameters, and the force performance of steel anchor boxes during the iterative process, and to generate more accurate prediction and evaluation values.

Analysis Of The Addition Of Steel Plates Reviewed to The Compresivve Strength Capacity Of The T-Beam

Reinforced concrete is used in various constructions, such as buildings, bridges, dams, road pavement, tunnels, etc. Structural strengthening of reinforced concrete beam can be done in various ways, which one is the addition of steel plates bonded to the compression area. Steel plates with a width of 150 mm and 300 mm with a thickness of 2 mm are expected to increase the compressive strength of reinforced concrete beams. Plate installation uses Sikadur 31 CF-Normal adhesive to attach steel plates and beams, and it is hoped that composite properties will occur on both of them. The test object samples were 5 beams consisting of 1 control beam and 4 reinforcement beams with a quality of 10 MPa. The beam sample has dimensions of 75 mm flange width and 80 mm flange height, 150 mm bottom width, 250 mm h height, 300 mm top width. The flexural strength test was carried out with a loading frame in two-point loading. The results of the study of adding plates showed an increase in beam capacity compared to the control beam. The percentage increase in beam capacity of test objects BP 1(1) and BP 1(2) with 150 mm wide plate reinforcement was 17.19% and 18.85%. The increase in beam capacity of BP 2(1) and BP 2(2) specimens with 300 mm wide plate reinforcement was 26.82% and 28.02% respectively

Highly compressible concrete: The effect of reinforcement design on concrete’s compressive behavior at high strains

In squeezing ground tunnel construction, yielding elements must absorb the large tunnel deformation without damaging the tunnel lining. Various designs for these highly compressible structures exist. Still, they all share one commonality: they are complicated to manufacture, and it is difficult to alter their design to match desired compressive properties. A new yielding element design is presented here, consisting of corrugated metal plates embedded within fiber-reinforced concrete. As this yielding element is compressed, the corrugated plates are gradually flattened, increasing the plates’ stiffness. This mechanism enables the engineering of structures with monotonically increasing compressive stress–strain curves and matches the target compressive properties. When compared against alternate reinforcement schemes, including fiber reinforcement, flat plate reinforcement, and polymeric lattice reinforcement, compression results indicate that only the corrugated metal plate reinforcement produced monotonically increasing stress–strain curves while keeping stress levels below a prescribed limit. Additionally, the corrugated metal plate-reinforced specimens began densification at a strain 280% larger than the strain at which the fiber-reinforced samples began densification, indicating that the corrugated metal plates extended the yield plateau. Fiber-reinforced concrete in conjunction with corrugated metal plates shows promise for use as a yielding element.

Failure of urban subway segments in coastal area and reinforcement effect of bonded steel plate: a case study in China

The construction of metro in coastal areas is prone to safety accidents when it encounters unfavourable geology. Serious water inrush and sand gushing occurred during the construction of the shield tunnel connection channel of Shenzhen Metro Line 20, resulting in extensive deformation and even cracking of the shield segment. With the event as the background, it is conducted in this article with a further analysis of the causes of sand gushing in the connecting channel. Using convergence displacement and crack width as indicators, the shield segments are classified as strong influence zone, moderate influence zone, weak influence zone and no influence zone. Furthermore, by combining numerical simulation and field investigation, the innovative method of epoxy bonded steel plate reinforcement is proposed. In particular, it should be noted that the steel plate needs to be opened at the connection channel, so four small right-angle steel plates are designed to reduce the concentrated stress of the split ring. According to finite element analysis and on-site measurement, it can be known that after the steel plate is reinforced, the internal force of the segment is greatly reduced, and the deformation is stable, which can ensure the safe service of the tunnel. This research provides a new idea for the damaged reinforcement of urban subway segments in coastal areas in the future.

PERENCANAAN STRUKTUR ULANG GEDUNG BADAN PEMBERDAYAAN MASYARAKAT DAN NAGARI KABUPATEN PASAMAN BARAT

Building Planning The Community Empowerment Agency and Nagari is one of the government buildings, the planned building is a 3-storey office building located in the West Pasaman earthquake area. so planning is needed that leads to being resistant to earthquake shocks, this is one of the basics for planners to plan the Community and Nagari Empowerment Agency Building. From the results of this structural analysis, the reinforcement structure is obtained based on the author's analysis. The results obtained that the material used is steel fy = 420 MPa and concrete quality fc' = 24.9 MPa, for plate reinforcement in the direction of x = 10 – 150, while the direction of y = 10 – 150. Column planning uses quality fy = 420 and concrete quality fc' = 24.9 Mpa for a 40cm x 40cm column with the main reinforcement used, namely 8D – 16 and a 30cm x 30cm column with the main reinforcement used 6D – 16. While the beam design uses steel quality fy = 420 Mpa and muru concrete fc' = 24.9 MPa for beams measuring 50cm x 30cm with reinforcement used 6D – 16 16 for tensile reinforcement and 3D – 16 for compression reinforcement, steel quality fy = 420 and concrete quality fc' = 20.75 for beam size 45cm x 25cm with reinforcement used 4D – 13 for tensile reinforcement and 3D – 13 for compression reinforcement, while for beams using steel quality fy = 400 and quality beron fc' = 20.75 for size 30cm x 20cm with the main reinforcement used 3D – 12 for tensile reinforcement and 2D – 12 for compression reinforcement.reinforcement.

Novel Reinforcing Techniques and Bearing Capacity Analysis for Tunnel Lining Structures with Extensive Corrosion

Affected by the erosive environment, tunnel lining concrete in the long-term service zprocess often exhibits engineering diseases such as concrete corrosion degradation and loss of strength, decreasing the stability of the tunnel lining structure and the traffic safety. Based on HTG tunnel project, the basic distribution rule of tunnel lining corrosion and macro mechanical properties of corroded concrete were explored in this paper through engineering disease site investigation. Then, on this basis, aiming at large-scale corrosion of tunnel lining structure, two reinforcement and repair schemes are proposed, corrugated steel plate reinforcement method and channel steel reinforcement method. Indoor component tests are carried out on the two reinforcement schemes. The failure characteristics and stress and deformation law of tunnel lining members after reinforcement and repair were verified. The analysis showed that the failure process of the reinforced specimens on the tensile side could be divided into the non-cracking stage and the working stage with cracks, and the cracking load and failure load of the specimens were significantly increased. The bearing capacity of the reinforced specimens was divided into the ultimate bearing capacity against cracking and the ultimate bearing capacity during failure. Finally, the calculation methods of the bearing capacity of the channel steel reinforcement method and the corrugated steel plate reinforcement method were derived. Comparative analysis shows that the results of numerical simulation, experimental testing and theoretical simplification methods are close to each other, and the maximum deviation is less than 8%. The established method for calculating the bearing capacity of corroded components after reinforcement is reliable and can be used for the design calculation of corroded lining reinforcement.

Theoretical Analysis of Flexural Time-Varying Properties of Aluminum Alloy-Reinforced RC Beam under Atmospheric Environment

This paper aims to reveal the degradation of the flexural load capacity of reinforced concrete (RC) beams reinforced with aluminum alloy (AA) under atmospheric conditions. For the same, first, time-varying models of the flexural load capacity of RC beams were developed before and after reinforcement with AA and steel plate based on the time-varying properties of the materials. Subsequently, upon collecting existing test data, the reliability of the models was verified. Finally, the parameters of AA-reinforced and steel plate-reinforced RC beams were analyzed to investigate the influence of factors such as concrete cover depth, cross-sectional area of reinforcing material, and cooperative working coefficient of reinforcing material and concrete (demonstrate the ability of reinforcement material and concrete to work together) on the remaining service life, rust initiation time, and cracking time. The results show that under atmospheric environment, the flexural time-varying degradation model for RC beam can be divided into three stages: pre-rusting, rusting-pre-cracking, and post-cracking, with differences in the dominant factors at each stage. In terms of long-term performance, AA reinforcement is significantly more efficient than steel plate reinforcement. This study provides some theoretical basis for the design of AA reinforcement in the atmospheric environment.

Study on Lateral Distribution Coefficients of Hollow Slab Bridges After Reinforced by Pasted Steel Plates

This paper adopts a new method of pasting steel plate to restore the transverse connection of hollow slab bridge, so that the strengthened bridge can meet the requirements under the state of serviceability. The original beam of the concrete hollow slab with a span of 8m from the Suizhong to Shenyang section of Jing-Shen highway was reinforced by a method of pasting steel plates. In the test the eccentric load condition was loaded and the abaqus software was used for numerical calculation after the reinforcement. Based on the theory of load transverse distribution coefficient of bridge structure, different calculation methods were used to obtain the transverse load distribution coefficient of the strengthened test beam, and it is verified that the hinged plate method can be used to calculate the hollow slab beam strengthened with steel plate. In addition, combined with previous calculations, test results and numerical analysis, this paper discusses the restoration effect of the new type of pasted steel plate reinforcement method on the bridge lateral connection. The results show that the hinged plate method can be used to calculate the load lateral distribution coefficient of hollow slab beams strengthened by pasted steel plates. therefore, the pasted steel plate reinforcement method can effectively restore the horizontal connection between the hollow slabs and meet the use of bridge structures.

Tensile behaviour of transverse reinforcement with different connection methods in single steel-plate concrete composite structures

Transverse reinforcement is key to the single steel-plate concrete composite (SSC) structure when subjected to out-of-plane shear and impact load. This research focuses on the tensile behaviour of two connection methods between transverse reinforcement and steel plate in SSC structure, namely the tie bar interlocked with the J-hook connector (TBIJC) and the tie bar overlapped with the headed stud (TBOHS), which are much more convenient in construction compared to direct welding connection. Pull-out tests are carried out on 10 groups of specimens with different detail parameters to verify their reliable performance. Various types of failure modes and corresponding experimental phenomena are observed and recorded. The interfacial slip between the tie bar and concrete was measured to reflect the load–deflection characteristics. Parametric studies are carried out on the tensile performance considering connector shape and dimensions, end-anchor form of the tie bar and concrete strength. Plastic limit analysis is performed based on twin shear strength criterion for concrete, and an analytical model is developed to predict the ultimate tensile resistance. The accuracy of the proposed model is validated against the test results. Finally, based on the test results, design suggestions are proposed for the tie bar connection details considering both mechanical performance and construction efficiency.

PEMBEBANAN MODEL PELAT SKALA KECIL PERKERASAN KAKU (RIGID PAVEMENT) DI ATAS TANAH PASIR

Road infrastructure issues need great attention, considering that this was a link and a cross-economy between one region and another. Damage to the pavement (pavement) would have fatal consequences for the development of an area and an increase in financial needs. Therefore, it was necessary to strengthen a solid road body so that it was able to strengthen the road and be comfortable for traffic loads to pass. Damage to the road body was a major concern in road maintenance efforts. This was due to several very complex problems in terms of the materials used, work implementation, traffic loads passing through the road body, and existing natural conditions. This research studies and analyses the behavior of dynamic-loaded rigid pavements. This load was a traffic load model, and the behavior was reviewed in a small-scale laboratory model. The expected result was to know the model’s behavior with and without rigid pavement reinforcement on both sandy and soft soils, namely in the form of analysis and the ability of the reinforcement to accept traffic loads. This research showed that the plate test model shows that multiple plate thickness supports plate stiffness. The cakar reinforcement plate affected the stiffness of the plate. The deflection value due to loading on the 3-layer plates (6.3 mm thick) was comparable to the 1-layer plate (2.1 mm) with cakar. FEM analysis can be performed to predict deflection due to loading in the center of the plate, and this value was very close to the results of the laboratory small-scale loading test. The CBR value used to calculate the deflection was closest to the real condition, namely the value before loading 0.2 kN and after loading 0.8 kN.

DESIGN AND STRUCTRAL ANALYSIS OF HIP-JOINT IMPLANT

An artificial joint (prosthesis) helps reduce pain and improve function. Also called total hip arthroplasty, hip replacement surgery might be an option if hip pain interferes with daily activities and nonsurgical treatments haven't helped or are no longer effective. We review the different materials, constructions, and surfaces used in the development of femoral stems, in order to solve and avoid various problems associated with their use. Femoral stem prostheses have undergone substantial changes and design optimizations since their introduction In this project a new design of hip joint implant is introduced by using Ti6Al4V(alpha-beta Ti alloy), Cobalt Chromium(Co Cr) alloy, 316L stainless steel alloy materials. All the parts are designed in CATIA V5.18 and static structural analysis was done in ANSYS WORKBENCH. The equivalent (Von Mises) stresses are analyzed and deformation of the Hip joint for all the three materials are compared. Also, Ti6AL4V has better properties that are similar to bone compared to the rest of the bio materials that are considered during the project work. KEYWORDS: Implant, Femoral stem, Femoral head, Plastic liner, Acetabular component, Support plate, Structural analysis.