Steel Research Articles

Reconstruction of nonstationary sound field based on group sparsity time domain equivalent source method

To improve the accuracy and stability of reconstruction of nonstationary sound field, a novel time domain equivalent source method based on non-convex overlapping group sparsity (NOGS-TESM) is proposed. In the proposed NOGS-TESM, the time-varying pressure in the near field is first modeled by a set of equivalent sources positioned inside the vibrating structure. Then, the NOGS regularization is applied for solving the inverse problem, and a novel algorithm derived on the basis of Majorize-Minimization theory is utilized to obtain the optimal solution of equivalent sources strengths. Finally, the optimal equivalent sources strengths at all times are substituted into a time-domain convolution to calculate the time-varying pressure of reconstruction surface. The proposed NOGS-TESM enriches the prior information by considering the group sparsity of spatial pressure distribution, and enhances the accuracy of estimated equivalent sources strength via its alternative calculation of l0−norm. A vibrating plate to produce a nonstationary sound field, which is designed as a numerical simulation, and the time-varying pressures of measurement surface are input into the proposed NOGS-TESM. The quantitative and qualitative comparisons confirm that the proposed NOGS-TESM can greatly reconstruct the non-stationary sound field in time–space domains, and its reconstruction accuracy is higher than that of TESM with Tikhonov regularization (TR-TESM). Meanwhile, several parameters, for example, the noise and position of equivalent source surface, are discussed in detail, and the superiorities of the proposed NOGS-TESM in terms of stability and robustness are proved by comparing to TR-TESM. The predominance of the proposed NOGS-TESM is further validated by conducting one experiment on the vibrating steel plate.

Performance of profile steel CFDSP composite walls under compression and bending loads

To satisfy the demands for high load-carrying capacity, rapid construction, and economic feasibility in high-rise residential apartments, the authors developed a novel profile steel concrete-filled double-steel-plate (CFDSP) composite wall. Experimental investigations were conducted to evaluate the load-carrying capacities and failure modes of composite walls subjected to compression and bending loads. Refined finite element (FE) models for the walls were established and validated by comparing with experimental results. The effects of critical parameters such as axial compression ratio, concrete strength, shear span ratio, steel plate thickness, and strength on the load-carrying capacities and failure modes were analyzed. Results indicate effective collaboration between concrete and steel, with the internal concrete being fully constrained by steel plates and profiled steels. The load-carrying capacity and stiffness of profile steel CFDSP composite walls increase initially and then stabilize with the increase in axial compression ratio, while the deformation capacity decreases with the increase in axial compression ratio. An increase in shear span ratio accelerates the degradation of load-carrying capacity and stiffness, while also resulting in a decrease in ductility. Additionally, an increase in concrete strength, steel plate strength, and thickness can enhance the load-carrying capacity and stiffness, with a relatively minor impact on deformation capacity. Simplified prediction formulas for determining the resistance of composite walls under compression and bending loads are developed. The evaluation results closely align with experimental data, showing less than a 5 % error, thereby providing valuable guidance for the performance-oriented design of profile steel CFDSP composite walls.

A seismic retrofit strategy involving steel haunch and external prestressing for non-ductile reinforced concrete knee joints

Previous studies have confirmed the vulnerability of reinforced concrete (RC) knee joints under cyclic loading, however, there remains a lack of studies on their seismic retrofitting. This study proposes a retrofit strategy aimed at enhancing the seismic performance of knee joints by acknowledging their unique behavior. The strategy involves a novel arrangement of steel plates that optimizes the effectiveness of steel haunch and external prestressing methods. To evaluate this approach, six full-scale knee joint specimens—two controls and four retrofitted—were fabricated using nonseismic reinforcement details and subjected to reversed cyclic loading. Vital parameters, including load, displacement, and strain responses along the reinforcement bars and steel plates, were monitored throughout the tests. The specimens retrofitted with this newly proposed strategy demonstrated a significant improvement in seismic performance by effectively distributing the prestressing force to the core of the joint and promoting beam flexural failure. The lateral strength significantly increased, with maximum enhancements of 100 % and 200 % under closing and opening rotations, respectively. Additionally, the retrofitted specimens dissipated at least 100 % more cyclic energy compared to the control specimens. Furthermore, the proposed distribution of the prestressing force within the joint core was instrumental in restraining the expansion of diagonal cracks. Consequently, this study makes a substantial contribution to the body of knowledge on RC knee joints and promotes their practical implementation under different conditions.

Investigation into fatigue failure of cable brackets and vibration suppression methods

The cable bracket is one of the most important components of high-speed EMUs, as it supports the cables of sensors. The fatigue failure of the bracket can severely affect the operation of the vehicle. In this study, the dynamic response of the cable bracket, including dynamic stress and acceleration, is obtained through field tests. The results show that the modal vibration of the bracket excited by high-frequency excitation in the wheel–rail system is an important cause of fatigue failure of the bracket. Rail welded joints in the track and polygonal wear of the wheelset further exacerbate the vibration and of the bracket. A model of the virtual vibration table is proposed to simulate the actual excitation experienced by the bracket. The effects of the cantilever beam length, steel plate thickness, and pre-tightening torque of the bolts on the dynamic stress of the bracket are studied using the virtual vibration table. Several vibration suppression methods are proposed. The results indicate that the dynamic stress of the bracket caused by the rail welded joints can be effectively reduced through the adjustment of the pre-tightening torque of the bolts or the appropriate reduction of the cantilever beam length. The findings of this study can serve as a reference for suppressing vibration and preventing fatigue failure of the bracket.

Capacity reinstatement of reinforced concrete one-way ribbed slabs with rib-cutting shear zone openings: Hybrid fiber reinforced polymer/steel technique

This study examined the use of two configurations for capacity restoration of reinforced concrete (RC) one-way ribbed slabs containing openings in shear zones. Four specimens of half-scale comprised three ribs in addition to a top RC slab. The test plan included a control specimen without openings, one with two rib-cutting shear openings, one strengthened using a blend of carbon FRP (CFRP) composites and steel plates, and another retrofitted with a combination of glass FRP (GFRP) composites and steel plates. The two strengthening schemes were found successful at fully restoring the ultimate load of the specimens. The ultimate load of specimen strengthened using the hybrid CFRP/steel system exceeded the control slab without openings by 52%. However, in the other specimen where a mix of steel plates and GFRP sheets was used, the load capacity was only 5% less than the control specimen without openings. While the dissipated energy and stiffness were reinstated and improved for the hybrid CFRP/steel system, they were partially restored for the GFRP/steel system. Additionally, a prediction approach was developed to estimate the maximum load of the slabs. The developed approach considered potential shear and flexural modes of failure, providing close predictions of the ultimate load.

Investigating corrosion-induced deterioration in bolted steel plate joints using guided wave ultrasonic inspection

AbstractBolted steel plate joints encounter challenges posed by joint corrosion, which impact the quality of interfacial contact among the bolted components. Unfortunately, no correlation between corrosion-induced joint damage and preload, nor an existing numerical model capable of capturing such effects, has been identified. This study aims to utilize guided wave ultrasonic investigation to examine the deterioration of interfacial contact caused by corrosion in bolted joints. Additionally, a contact modification-based numerical approach is presented to capture the effects of changing interfacial stress during joint corrosion. Guided wave mode selection was conducted with some preliminary experiments supplemented with the theory of wave mode dispersion, hence leading to the selection of S0 and A0 mode existing at 300 kHz. The joint was then corroded in a controlled manner using an electrochemical process while simultaneous ultrasonic measurements were taken. The experimental observations highlighted the progressive dispersion in the transmitted A0 mode across the bolted joint, potentially due to changing interfacial stress boundaries between the plates. A damage parameter, termed the dispersion index, was developed based on the energy ratio of different signal sections. A linear change in the dispersion index was observed with the increase in corrosion-induced mass loss. The insight was further established through a numerical investigation by studying the effect of changing bolt preload and the corresponding interfacial stress distribution. The findings revealed that monitoring the changes in the stress distribution at the bolted interface can provide insight into interfacial corrosion. Eventually, destructive tension test results confirmed the effect of joint corrosion on the load-bearing capacity of the joint. The change in failure mode of the pristine and corroded specimen is observed. The reported approach establishes the potential of ultrasonic inspection to investigate the interfacial health of a bolted joint in corroding conditions.

A novel UV-curable composite coating with superior anti-corrosion and mechanical properties

The UV curing method is free from volatile organic compounds (VOC) and exhibits high curing efficiency. However, pore flaws and inadequate mechanical qualities after cure greatly hinder their utilization in metal anti-corrosion. Herein, layered double hydroxides (LDH) supported by molybdic acid and cerium ions were synthesized in situ on the sericite (SC) surface, enhancing the shielding, corrosion inhibition, resin compatibility, and cross-linking density of the coating. Compared with carbon steel immersed in a 3.5 wt% NaCl solution, the incorporation of SC/KH560@LDH reduced the corrosion current density (Icorr) from 2.001 × 10−5 A/cm2 to 7.883 × 10−6 A/cm2. Moreover, the low-frequency impedance of the UV-SC/KH560@LDH coating remained high at 1.939 × 1010 Ω·cm2 after 70 days of immersion in a 3.5 wt% NaCl solution. The excellent corrosion resistance of UV-SC/KH560@LDH can be attributed to the barrier properties of the filler, the chloride ion trapping, and the passivation effect. Furthermore, the UV-curable alkyd resin used in this work formed a chemical bond with the metal substrate, enhancing the mechanical properties of the coating. The adhesion strength of the UV-SC/KH560@LDH was measured at 11.50 MPa. The thickness loss (21.3 μm) of the UV-SC/KH560@LDH were minimal after 5000 cycles of wear. A new research concept for preparing the UV-SC/KH560@LDH with superior anti-corrosion and mechanical properties for carbon steel plate surfaces has been proposed to meet the demands of practical applications.

Stress characteristics and cracking mechanism of web-to-stiffener weld in steel plate girder bridges under bending-shear action

The web-to-stiffener weld was subjected to bending-shear action, which was always neglected in previous research and affected the accuracy of fatigue evaluation. In this study, multi-scale FEMs (finite element models) of steel plate girder bridges were established to investigate the deformation characteristics, thus revealing the generating mechanism of bending-shear action. The fatigue comparison tests under bending-shear load and bending load were conducted to identify the cracking mechanism and its impact. The stress characteristics at the weld end were further explored through the structural mechanical model and verified by FEMs. The results show that the bending-shear action was caused by the inward and downward pulling by the stiffener on the web, and would lead to a premature transition from fatigue cracking to brittle fracture. The ratio of shear stress to normal stress was independent of load, inversely proportional to gap height, and positively related to web thickness, which could provide support for the accurate fatigue evaluation of web-to-stiffener weld.

The Performance of a Circular Excavation Supported by a Prefabricated Recyclable Structure in a Full-Scale Test

Excavations for underground structures, such as working shafts, underground grain silos, and parking garages, are characterized by uniformity, consistent dimensions, large quantities, and strict timelines. Prefabricated recyclable supporting structures (PRSS) are gaining attention over traditional retaining structures due to their standardized design, efficient construction, and reusability, which suit such excavations better. To validate their performance, full-scale tests are conducted to analyze the deformation and stress characteristics of PRSS. The results show that the average maximum lateral displacement of supporting pile is 0.07% of the excavation depth (He), roughly half that of steel plate. Differences in ground surface settlement behind steel plates and the supporting piles are not as significant as those in their lateral displacements. While the displacement of the supporting piles is insufficient to induce soil movement into the active limit state on the non-excavation side, the circular excavation’s arching effect reduces the earth pressure on this side of the supporting piles below the active earth pressure limit. Furthermore, the earth pressure acting on the steel plates is lower than that acting on the supporting piles, suggesting the presence of a soil arching effect between two adjacent piles. These findings offer valuable insights for guiding the construction of PRSS.

Characterization of different longitudinal shear transfer mechanisms for profiles embedded in concrete walls

Concrete walls or columns reinforced by one or multiple embedded steel profiles have gained popularity due to their improved strength, ductility and energy dissipation capacity. However, certain gaps in information are remaining in the available standards regarding the design of such non-conventional reinforced concrete systems. In particular, a proper characterization of the longitudinal shear transfer properties at the steel-concrete interface is required for a reliable design. Although sufficient information is available regarding mechanical connectors like shear studs, detailed information is required for any other types of mechanical connectors such as welded steel plates or for configuration without mechanical connectors. Moreover, even for cases with mechanical connectors, the orientation of the profile – and hence the distance to the face of the concrete – and the tying system can have a significant influence on the load transfer mechanisms. To this purpose, this article presents the outcomes of a set of push-out tests with the objective of comparing the force transfer mechanisms from the steel profile to the surrounding concrete wall for different types of interfaces. 13 tests specimens are investigated, with flexible (shear studs) and/or rigid (steel plates) shear connectors, considering different orientations of the profile and tying mechanisms, as well as a comparison with profiles without mechanical connectors. Based on the test results and subsequent analytical assessment, relevant conclusions are drawn regarding the longitudinal shear transfer at the steel-concrete interface. If necessary provisions are followed, welded steel plates prove to be an effective alternative to the shear stud connectors in terms of connector strength. The orientation of the embedded steel profile, consequent position of the mechanical connectors and their distance to the concrete face are observed to have a significant influence on the compression strut evolution, which therefore dictates the necessity (or not) of horizontal confinement or ties. Furthermore, combining the shear strength offered by different types of mechanical connectors and the steel-concrete bond offer a precise estimate of the longitudinal shear strength and therefore indicates towards the conservative nature of the design provisions suggested by the available standards.

THE EFFECT OF A Cr-FREE FINGERPRINT-RESISTANT PASSIVATION FILM ON THE PERFORMANCE OF HOT-DIP 55 % Al-Zn COATED STEEL

Cr-free fingerprint-resistant hot-dip 55 w/% Al-Zn coated steel (CFAZCS) is a upmarket steel plate product that is widely used in consumer goods with high added value, such as LCD back panels for monitors, as well as various electrical and electronic products. Passivation is a crucial process in the production of CFAZCS, greatly affecting the overall performance of the CFAZCS product. A comprehensive evaluation of passivation films from different manufacturers on the performance of CFAZCS can assist production enterprises in optimizing and controlling the product quality according to the requirements of target customers. This article comprehensively tests and evaluates the performance of corrosion resistance, acid/alkali resistance, anti-yellowing/blackening, paint adhesion, abrasion resistance, fingerprint resistance, and the conductivity of mainstream, commercially available, Cr-free, fingerprint-resistant, passivation solutions, providing guidance for the selection of passivation solutions in production processes.

Eddy Current Sensor Probe Design for Subsurface Defect Detection in Additive Manufacturing.

Pore and crack formation in parts produced by additive manufacturing (AM) processes, such as laser powder bed fusion, is one of the issues associated with AM technology. Surface and subsurface cracks and pores are induced during the printing process, undermining the printed part durability. In-situ detection of defects will enable the real-time or intermittent control of the process, resulting in higher product quality. In this paper, a new eddy current-based probe design is proposed to detect these defects in parts with various defects that mimic pores and cracks in additively manufactured parts. Electromagnetic finite element analyses were carried out to optimize the probe geometry, followed by fabricating a prototype. Artificial defects were seeded in stainless steel plates to assess the feasibility of detecting various flaws with different widths and lengths. The smallest defect detected had a 0.17 mm radius for blind holes and a 0.43 mm notch with a 5 mm length. All the defects were 0.5 mm from the surface, and the probe was placed on the back surface of the defects. The surface roughness of the tested samples was less than 2 µm. The results show promise for detecting defects, indicating a potential application in AM.

Perancangan Mesin Pengupas Singkong dengan Metodologi NIDA-QFD untuk Industri Keripik Singkong ABC Banyuwangi

Banyuwangi produces potential cassava chips. However, due to slow manual stripping, production capacity is low, market demand is high, and product quality decreases. This study develops an optimized peeling machine using NIDA-QFD to meet user needs and increase innovation. Experimental design model and 5 alternative actions of cassava peeling machine. ABC Banyuwangi Industry with 10 respondents, including owners and employees, was given intervention in the action decision. NIDA-QFD developed a cassava peeling machine design that is efficient and minimizes risk. Alternative 3 was chosen, with user body dimensions (height 110-180 cm), using sturdy materials (steel angle profile, stainless steel plate), and having 5 peeling rolls (diameter 80 mm, length 910 mm) for an effective and efficient stripping process. The 220 volt 1/2 PK AC drive system ensures the roll rotates with optimal speed and torque. The cassava skin remover is made of stainless steel which is rust-resistant and easy to clean, so it is feasible to overcome the problem of manual peeling of cassava and opportunities for progress in the cassava chips industry.

Experimental Study on a Damage-Control and Repairable Fully Precast Beam-Column Joint

ABSTRACT A novel joint with a splice lap was proposed, which was damage-control and repairable fully precast beam-column joint (DRBJ) connected by energy-dissipating connecting steel plates to remarkably diminish the residual displacement of an RC frame under strong earthquakes and ensure the rapid rehabilitation of the structure. Four one-half scale beam-column-joint specimens were designed and fabricated in different connection forms and lap lengths, and one of the specimens was loaded again under the same conditions after repair. Low cyclic loading tests on DRBJ were conducted to investigate their hysteresis curves and energy-dissipation capacities. The test results revealed that the plastic deformation of DRBJ was concentrated on connecting steel plates, while the residual displacement was small. The deformation and bearing capacities of the short-lap joint were higher than those of the long-lap junction, and the bearing, energy consumption, and deformation capacities of the DRBJ connected by strip plates were still superior to those of the DRBJ connected by the rectangular plates. The DRBJ showed satisfactory repairability and energy-dissipation capacity with the help of the strip plates. A simplified force–displacement model was established based on the analysis of the functioning mechanism of DRBJ. The calculated results of the rotational stiffness and the test results agree well, which can provide a reference for the design of this type of splice joint.

The Steelmaking Transformation Process and Its Consequences for Slag Utilization

The main challenge of the European steel industry for the next decade is the steel production transformation process. Many steel producers aim to avoid their CO2 emissions by substituting the CO2‐intensive blast furnace/basic oxygen furnace route by a gas‐based direct reduced iron (DRI) process combined with an electric smelting process. Thus, the well‐known latent hydraulic granulated blast furnace slag (GBS) will vanish step by step. For more than 140 years, this slag has been used as a supplementary cementitious material due to its clinker reduction potential and from there its CO2 reduction potential for the cement and concrete production. Moreover, slag cements offer some special technical advantages. Whereas the solid‐state DRI process itself does not generate any slag, the different electric smelting processes will produce liquid steel or “electric” pig iron, respectively, together with very different types of slags. However, specific slag/metal ratios, resulting slag volumes, chemical and mineralogical composition, and physical properties of the new slags are yet unknown. Therefore, their cementitious and environmental properties are also still unknown. Different current and scheduled projects aim mainly to enable the different types of new slags to substitute GBS to continue the successful cross‐industrial cooperation between steel and cement industry.

Design and mechanical response analysis of asphalt steel plastic pavement structure

In order to further study the mechanical properties of new asphalt steel plastic (ASP) pavement and explore optimal ASP pavement structures, this study analyzed the bottom tensile strain of asphalt mixture layer, the bottom tensile stress of steel plate layer, the bottom tensile stress of acrylonitrile butadiene styrene (ABS) layer, the top vertical compressive strain of subgrade and deflection. The results show that when the pavement structure adopts an 8 cm thick SMA layer, a 0.5 cm thick insulation layer, a 20 cm thick ABS layer, and 0.6 cm, 1.0 cm and 1.2 cm thick steel plate layers respectively, the mechanical properties of the ASP pavement are relatively good. The variation in the thickness of the steel plate layer has a greater impact on the bottom stress of steel plate layer. For the same pavement structure, when the dynamic load increases from 0.5 MPa to 0.9 MPa, the maximum values of the design indexes are linearly related to the dynamic load values. Under the static load, the shear stress generated in the steel plate layer is significantly lower than that in asphalt and ABS layers. The new asphalt steel plastic pavement has good mechanical properties and great application potential.

Experimental and numerical investigation of arc-shaped corrugated steel plate damper

Shear panel damper (SPD) is a commonly utilized hysteretic steel plate damper for energy dissipation. However, the premature buckling of the web plate of SPD has become a major issue, leading to a reduction in the strength and energy dissipation capacity of the damper. Various solutions have been proposed to address this issue, however, unfavorable factors, such as the introduction of additional residual stresses and the potential weakening of the web plate, would reduce the energy dissipation capacity and ductility of the damper and considerably complicate the overall configuration. This study proposes an arc-shaped corrugated steel plate damper (ACSPD) as a solution to enhance the buckling resistance of the web plate. The primary objective of this study is to investigate the mechanical behavior, energy dissipation capacity and failure mode of ACSPD with different configurations and compare against SPD. Quasi-static experimental tests were conducted on two SPD specimens and three ACSPD specimens, followed by further finite element analysis. The test and numerical results indicate that the ACSPD provides improved out-of-plane buckling resistance while preserving the same energy dissipation mechanism and similar mechanical characteristics as its SPD counterpart.

Inhibitory Effect of Fennel Fruit Essential Oil and Its Main Component Anethole of Corrosion on Steel Plates in 1 M HCL

Corrosion worldwide causes large losses of metal, which is why various ways are being sought to slow it down. The aim of this study was to investigate the inhibitory effect of fennel fruit essential oil (Foeniculum vulgare Mill.) and its main component anethole. The inhibitory effect of three different concentrations of the fennel essential oil and anethole (1.0 mL/L, 1.5 mL/L, and 2.5 mL/L) in a solution of 1 M HCl at 298 K for 6 h on a sheet of low-carbon steel was investigated. The inhibitory effect was established using gravimetric methods evaluating weight loss, corrosion rate, and inhibition efficiency, as well as electrochemical methods. In gravimetric studies, the inhibition effect of the inhibitors fennel essential oil and isolate anethole at a concentration of 2.0 mL/L was 70.85% and 45.86%, respectively. The anodic polarization curve data at 298 K demonstrate that the anethole and fennel essential oil adsorption on the metal surface creates a barrier that hinders hydrogen ions’ access and prevents them from being reduced on the steel surface’s cathode sites. Fennel essential oil acting as a mixed type-inhibitor can replace synthetic organic substances and could become an alternative to be used as environmental corrosion inhibitors.

Glued-in steel plate and screwed connections in Timber–Concrete Composites systems: Mechanical performance and design implications

This paper presents a comparative study between Timber–Concrete Composite (TCC) systems with glued-in steel plates and screwed connections. The research focuses on evaluating the structural performance of these connections, with a particular focus on the innovative glued-in steel plate through full-scale four-point bending tests on floor subassemblies with a 7.5 m span, complemented by push-out tests for assessing the behaviour of the slab-beam connection. The study aims to determine if the glued-in steel plate, a more economical option, can replace screws without significantly compromising the TCC system’s stiffness or strength. The findings reveal that while the glued-in steel plate connections exhibited lower stiffness and ductility compared to screwed connections, they demonstrated a significantly higher load-bearing capacity. Specifically, the glued-in connections achieved capacities ranging from 670-720 kN, markedly exceeding the 300-350 kN and 480-520 kN capacities of specimens with fewer and more screws, respectively. These results suggest that glued-in steel plate connections can effectively replace screws in TCC systems, offering a cost-effective alternative without significantly reducing structural integrity. Moreover, the paper evaluates how to design TCC floors by estimating the effective number of connectors and the effective length of the glued-in steel plate using an iterative γ-method. This is done to account for changes in stiffness, as determined from push-out tests and observed in bending tests. The iterative γ-method’s findings have been validated against the predictions of a Finite Element model.

Calculation Method of New Assembled Corrugated Steel Initial Support Structure of Highway Tunnel

The assembled corrugated steel initial support structure is a new prefabricated structure in highway tunnel engineering, achieving a balance between economy and safety. This study proposes a simplified calculation method and elucidates the mechanical mechanisms of assembled corrugated steel initial support structures. Firstly, the stiffness characteristics of corrugated steel plates were studied based on full-scale tests. A general equivalent stiffness coefficient table was established. Numerical simulations of corrugated steel flange joints were conducted to explore their bending mechanical properties. A two-stage rotational stiffness model for corrugated steel flange joints was proposed. Finally, a plane strain-spring simplified calculation method for the assembled corrugated steel initial support structure was developed, and the monitoring data from the Qipanshan Tunnel validated the correctness and reliability of the proposed method. The results demonstrate that (1) the plane strain-spring simplified model consists of the planar strain equivalent calculation method for corrugated steel plates and the two-line stiffness equivalent spring of the corrugated steel flange joint. The simplified model was validated as effective by monitoring data. (2) Corrugated steel plates exhibit two stages under loading, namely gap elimination and elastic stages. The elastic stage stiffness of corrugated steel plates decreases with increasing ratio of depth to pitch (RDP), positively correlating with plate thickness when the RDP exceeds 0.333 and otherwise negatively correlated. (3) Corrugated steel lining flange joints exhibit distinct elastic and plastic stages in their linear moment–rotation curves under loading.