Steel Plate Shear Wall Structure Research Articles

Cyclic behavior of improved low-yield point steel plate shear walls with T-shaped stiffeners

Based on the demand for high-performance lateral force-resistance systems for high-rise buildings, a new stiffened low-yield point (LY) steel plate shear wall (SPSW) structure is proposed. The infill plate is made of LY steel, and the stiffeners adopt a T-shaped section with greater flexural stiffness. Quasi-static tests are conducted on one unstiffened low-yield point steel plate shear wall (L-SPSW) and two stiffened L-SPSWs (using T-shaped cross and diagonal stiffeners). The cyclic behaviors of the L-SPSWs are compared through failure mode, damage development, hysteresis performance, and deformation performance. Numerical models are established and validated through experimental results. Finally, the performance of L-SPSWs with T-shaped and plate-type stiffeners is analyzed. The results show that the T-shaped cross stiffeners have the greatest enhancement in energy dissipation capacity (EDC) and stiffness, as well as the strongest suppression of the out-of-plane deformation (OPD) of the whole plate. T-shaped diagonal stiffeners have the greatest impact on enhancing the bearing capacity. It is suggested to strengthen the weld quality or select a steel material with LY for the diagonal stiffeners to ensure ductility. The use of T-shaped stiffeners can maximally improve the restraining effect on the OPD of the infill plate by 38.1 % compared with plate-type stiffeners.

Lateral behaviour of steel plate shear wall with cold-formed steel strips reinforcing door opening

Holes in the walls of buildings are occasionally necessary to fulfil buildings’ functional requirements. When a steel plate shear wall (SPSW) is used as the primary lateral force-resistant structural member in a building, the effect of such openings on the mechanical properties of the SPSW is non-negligible. In this study, reinforcement of SPSWs with door openings using prefabricated cold-formed steel (CFS) strips is proposed. The proposed method can improve the mechanical properties of SPSWs with openings without inducing the residual deformation and stress caused by the typical welding reinforcement method. Cyclic loading tests were conducted to analyse the lateral resistance of two perforated SPSW structures reinforced using the proposed method: one SPSW with a door opening in the centre, and another with the door opening positioned at its edge. The test results showed that the openings reduced the lateral stiffness and strength of the structures. Specifically, a 30.84% decline in ultimate strength was observed for specimens with central door opening, while a 32.78% reduction was noted for specimens with edge door opening. Finite element models were derived and evaluated based on these results, and an SPSW with openings reinforced by CFS strips was modelled as equivalent to an SPSW without openings for analysis. The proposed simplified analysis model realises the weakening effect observed in a perforated SPSW by reducing the thickness of the equivalent unperforated SPSW. Finally, the equivalent analysis model (EAM) proposed herein was compared with experimental results, with the errors in yield strength and ultimate strength both within 5%. The results demonstrating that the proposed EAM is accurate and reasonable.

Experimental study on CFRP-strengthened bolted splicing modular steel plate shear wall

The seismic performance of the steel plate shear wall (SPSW) structure will be weakened by the modular splicing of the infill steel plates. To address this, carbon fiber reinforced plastic (CFRP) was used to strengthen its splicing joints. First, the specimens of CFRP-strengthened bolted joints with different CFRP laying methods were tested in uniaxial tensile control, and the corresponding design method was proposed. Next, this method was introduced into the vertical splicing joints of modular SPSWs. Three 1/3-scale SPSW specimens, with and without CFRP-strengthened modular SPSW and complete SPSW, were tested under quasi-static cyclic loading. The failure modes and hysteresis performance of the three structures were compared, and the effects of using CFRP-strengthened splicing joints on various properties of the SPSW structure were investigated. The force mechanism of the CFRP-strengthened bolted splicing modular SPSW structure was further investigated by finite element (FE) analysis. The results indicated that the CFRP strengthening vertical splicing joints can effectively reduce the stress concentration around the hole walls of the infill steel plate, improve the performance loss of wall plates due to modular segmentation, and reduce slippage of splicing joints and out-of-plane deformation amplitude of wall plate. The CFRP-strengthened vertically bolted modular SPSWs increased the stiffness and load capacity of the structure, with yield bearing capacity and stiffness increased by 11.40% and 19.57% compared with those of the vertically bolted modular SPSW, respectively.

Behavior of frame-corrugated steel plate shear wall structure under cyclic loading

This manuscript innovatively presented a new type of assembled H-shaped steel frame-corrugated steel plate shear wall (HCSW). The hysteretic performance of assembled HCSW under cyclic quasi-static loading was investigated. The HCSW specimens with different corrugated steel plate thickness and axial compression ratio were fabricated. The H-shaped steel frame-flat steel plate shear wall (HPSW) was fabricated as control test specimen. The failure process, hysteresis curves, skeleton curves, lateral capacities, energy consumption and the other issues were discussed. The hysteretic performance of HPSW and HCSW was compared. It could be found that the hysteretic performance of HCSW was better than that of HPSW. The corrugated steel plate was yielded prior to frame column as a desirable sequence of material yielding. In addition, the finite element model was established to simulate hysteretic performance of HCSW specimen. The parameters included width-to-thickness ratio, width-to-height ratio, and axial compression ratio in this research. The effects of parameters on HCSW hysteretic performance were analyzed and discussed based on the finite element model. According to the research results, the recommended values of parameters were proposed based on the analysis results. Furthermore, the calculation formula of HCSW initial stiffness was presented. This research could provide a reference for the design and evaluate the application of current design of provision for assembled HCSW.

Genetic algorithm model of PEC column-steel plate shear wall with flush end-plate joints based on component method

The partially encased concrete (PEC) column-steel beam frame steel plate shear wall (SPSW) structure of semi-rigid joint has good cooperative working performance and seismic performance. In this paper, based on the EC3 component model, considering the contribution of the new concrete components in the PEC column to the initial rotational stiffness of the joint domain, the component model of the flush end-plate PEC column joint was established. A 1/3-scale two-story single-span flush end-plate PEC column-steel beam frame SPSW structure was tested under quasi-static cyclic loading. The OpenSees model of this structure was established, which was validated by test results. Parametric analysis of the additional damping ratio for semi-rigid joints was conducted using OpenSees. The suggested value of additional damping ratios for semi-rigid joints was given. Finally, based on Matlab and OpenSees, the model was input in the form of tool command language (TCL), an optimal arrangement model of flush end-plate PEC column joints with the genetic algorithm (GA) as the main procedure was designed. The effects of different arrangement schemes of semi-rigid joints on the seismic response of PEC column-steel beam frame SPSW structures were analyzed. The results show that the seismic performance of the flush end-plate PEC column-steel beam frame SPSW structures is reliable. The results of the finite element (FE) are in good agreement with the test results, which indicates that the established OpenSees model is effective. The contribution of the new concrete components to the initial rotational stiffness of the middle joints, top and bottom joints is 45.02% and 49.68%, respectively. The optimal arrangement scheme of semi-rigid joints can be efficiently computed by the proposed GA model.

Experimental Study on Steel Plate Shear Walls with Partially Encased Composite Columns Composed of Thin Steel Plate

The steel plate shear wall structure has excellent seismic performance, mainly consists of embedded steel plate, horizontal boundary elements (HBEs) and vertical boundary elements (VBEs). Under the action of additional bending moment, the VBEs of SPSW often produce the failure mode of “hourglass specimen”. As a solution, the SPSWs proposed in this paper adopts PEC columns, which are composed of concrete filled between flanges of thin-wall channel steel, and transverse steel bars welded between flanges to prevent it from buckling. A slow cyclic test was conducted on two specimens of 1/3-scaled prefabricated SPSWs with thin steel plate composite section PEC column. According to the validated finite element method, the parameters including the height-thickness ratio of filled steel plate, concrete strength grade, bolt spacing and axial compression ratio were also studied. The results show that the new structure has high bearing capacity and good ductility. In addition, the PEC column has enough stiffness to form a good anchoring effect for the inner steel plate. The inner steel plate fully yields after buckling and provides bearing capacity and energy consumption through the action of tension field. The peak load of specimens with concrete has a higher level approximately 18% than the no-concrete specimen. The height-thickness ratio has a great impact on the post buckling performance of SPSWs. With the increase of height-thickness ratio, the ultimate bearing capacity of the structure will increase by 10% – 30%. Moreover, to give full play to the outstanding performance of prefabricated SPSW with PEC column, the value range of bolt spacing is suggested to be in the range of 120 mm – 60 mm.

Study on seismic behavior of oblique CFRP corrugated plate-steel plate light weight sandwich composite shear wall

To improve the seismic behavior of the thin steel plate shear wall (SPSW), carbon fiber reinforced polymer (CFRP) is introduced into the thin SPSW, and polyethylene terephthalate (PET) foam is filled between CFRP corrugated plates and steel plate. An oblique CFRP corrugated plate-steel plate lightweight sandwich composite shear wall specimen (hereinafter: sandwich composite plate specimen) is designed. Furthermore, this paper compares the failure mechanism and hysteresis performance of the sandwich composite plate specimen and traditional non-stiffened SPSW specimen under the quasi-static test, and explores the influence of sandwich composite plate on the performance of wallboard. Finally, a simplified finite element model is established and its accuracy is verified by experiments. The results show that compared with the non-stiffened SPSW structure, the initial stiffness of the sandwich composite plate structure is increased by 34.0%, the energy dissipation capacity is increased by 38.44% when loads to 2% drift, and the maximum out-of-plane deformation is reduced by 93.24%. The sandwich composite plate structure shows obvious four-stage stress characteristics, and has good cooperative working performance before the CFRP corrugated plates debond in a large area, also plays a great role in anti-buckling.

Corresponding Intelligent Calculation of the Whole Process of Building Civil Engineering Structure Based on Deep Learning

This study proposes the first fully deep learning-based structural response intelligent computing framework for civil engineering. For the first time, from the data side to the model side, the structural information of the structure itself and any loading system is comprehensively considered, which can be applied to materials, components, and even structures, system and other multi-level mechanical response prediction problems. First, according to the characteristics of structural calculation scenarios, a unified data interface mode for structural static characteristics is formulated, which preserves the original structural information input and effectively reduces manual intervention. On this basis, an attention mechanism and a deep cross network are introduced, and a structural static feature representation learning model PADCN is proposed, which can take into account the memory and generalization of structural static features, and mine the coupling relationship of different structural information. Then, the PADCN model is integrated with the dynamic feature prediction model Mechformer and connected with the designed general data interface to form an end-to-end data-driven structural response intelligent computing framework. In order to verify the validity of the framework, numerical experiments were carried out with the steel plate shear wall structure as the carrier, in which a data augmentation algorithm suitable for the field of structural calculation was proposed to alleviate the problem of lack of structural engineering data. The results show that the deep learning model based on this framework successfully predicts the whole-process nonlinear response of specimens with different structures, the simulation accuracy is better than that of the fine finite element model, and the computational efficiency exceeds the traditional numerical method by more than 1000 times, achieving a qualitative improvement. It is proven that the intelligent computing framework has excellent accuracy and efficiency.

Lateral behaviour and failure modes of buckling-restrained beam-only-connected steel plate shear walls

In this paper, a new type of steel plate shear wall (SPSW) structure comprising square concrete-filled steel tube (CFST) boundary frame and infilled cold-formed steel (CFS) buckling-restrained beam-only-connected SPSWs is proposed. To study the lateral behaviour and failure modes of the buckling-restrained beam-only-connected SPSWs with square CFST frame, tests on a buckling-restrained beam-only-connected SPSW and a comparison specimen with unstiffened beam-only-connected SPSW with square CFST frame were conducted. The failure mode, hysteretic curve, shear capacity and energy dissipation capacity of the specimens under horizontal cyclic load were reported. The results showed that the two specimens had good lateral resistance and stiffness, which indicated that this structural system was a reliable SPSW structure. Besides, the arrangement of the CFS buckling-restraining strips could improve the seismic performance of beam-only-connected SPSWs. A total of 84 finite element (FE) models were developed and validated. Upon validation, the parametric analysis was carried out, and design method of the shear capacity of buckling-restrained beam-only-connected SPSWs was proposed. The results show that the newly developed design method is accurate and can better predict the yield capacity of CFS buckling-restrained beam-only-connected SPSWs.

A Numerical Investigation on the Limitations of Design Equations for Steel Plate Shear Walls

In previous studies various design issues on steel plate shear wall (SPSW) systems under lateral loading were investigated using analytical and experimental methods. However, these studies tried to examine the interactive effect of only a few of design parameters, such as panel aspect ratio, column flexibility parameter, axial load ratio on the boundary frame columns, web plate thickness, stiffness of horizontal and vertical boundary elements and top anchor beam, etc., on the drift capacity and shear force distribution among frame and panel components of SPSWs at a time. This study investigates the effect of all of these parameters in the same framework. A parametric study is conducted on finite element models of 292 3-story SPSWs with rigid beam-to-column connections and designed for specified parameters. By evaluating failure forms from finite element analyses, the limiting (undesired) cases resulting from different combinations of specified geometric properties are identified. A column flexibility factor of 2.2 is proposed instead of the current limit value of 2.5 for satisfactory column performance, improved drift capacity and balanced strength distribution among frame and panel of SPSW. The value of 0.75 for the ratio of plate shear force to total shear force has emerged as a critical threshold value for the strength distribution among plate and frame components in order to conform capacity design principles. This study provides a comprehensive look on the behavior of SPWS for determining the most suitable combination of various parameters in the design of SPSW structures.

Numerical modelling and equivalent brace model of cold-formed steel buckling-restrained steel plate shear walls

Cold-formed steel (CFS) buckling-restrained steel plate shear wall (SPSW) is a highly efficient lateral force resisting structure, which integrates architectural and structural functions. CFS stiffeners significantly reduces the out-of-plane deformation and improves the strength of SPSW. To investigate the effect of different arrangements of CFS on the buckling restraint of SPSW regardless of the effect of the surrounding frame, a finite element (FE) model of CFS buckling-restrained SPSW was developed and validated against the test results. Upon validation, a series of FE models were generated for parametric analysis. Based on the FE elastic buckling analysis method, the economic stiffness ratio of CFS to the steel plate was presented. Using the steel bar buckling theory, a simplified analysis model of the equivalent brace model considering the buckling-restrained effect of CFS on the steel plate was proposed. The simplified analysis model can consider the influence of buckling constraints and spacing on the buckling stress of the steel plate. Moreover, it can accurately simulate the stiffness and bearing capacity of the SPSW structure. The results show that the proposed simplified analysis model is accurate and consistent.

A Simplified Finite Element Model for Modular Steel Structure Building Wallboard through Experimental Research and Finite Element Analysis

The traditional research on steel plate shear wall structure mainly focuses on the overall performance of the wall, and the mechanical properties of the connection between plates and plates and between plates and frames are not clear. In this paper, the experimental research on the wallboard structure of bending plate was carried out and the mechanical properties and failure modes of five walls were analyzed. In addition, the connection properties between plates and frames were studied by finite element analysis. A simplified finite element model is presented by experimental study and finite element analysis. The results show that the finite element analysis results are in good agreement with the experimental results. The finite element model with the two-point binding constraint between the end of the bending plate and the angle steel can well simulate the mechanical properties of the steel plate shear wall structure.

Experimental and Numerical Study on Shear Behavior of Stiffened Thin Steel Plate Shear Walls by New Welding Process

Steel plate shear walls (SPSW) structures have been widely employed in multistory residential buildings. The traditional welding process may lead to serious welding deformation due to the thinness of the plate. In this study, a new welding process is proposed to ensure that the stiffeners and SPSWs bend as a whole, and the number of welds is reduced from 3 to 2. This process has better integrity than the traditional process owing to less welding residual stress and deformation. On the basis of low-cycle reciprocating load tests on four full-scale specimens, the shear failure pattern, hysteresis characteristics, and load-carrying capacity of SPSWs affected by the new process are studied, and the new welding process used in the vertical stiffener can meet the requirements of shear capacity. The influences of various parameters on the shear resistance of the SPSWs made by the new welding process are compared and analyzed. The results indicate that the lateral stiffness of the frame and the width–height ratios of the wall significantly influence the load-carrying capacity of the SPSWs. The SPSWs adopting the new manufacturing process are numerically simulated using ANSYS software. The same conclusions can be obtained by comparing the numerical results with the experimental results.

End-to-End Structural analysis in civil engineering based on deep learning

This paper presents DeepSNA (Deep Structural Nonlinear Analysis), the first general end-to-end computational framework in civil engineering that can predict the full range of mechanical responses of different structures based on deep learning. The proposed framework comprehensively considers intrinsic structural information and external excitations from both the data and the model. First, a data interface schema was carefully designed to eliminate manual interventions. Based on the distinctive characteristics of structural analysis, we proposed deep learning models for static and dynamic features that could identify underlying mechanical coupling relationships and historical dependencies. Moreover, we designed data augmentation algorithms to address the lack of data in real-world applications. Finally, we developed the DeepSNA framework and validated it with steel plate shear wall structures. The results indicated that the new framework was more accurate and had at least 1000 times greater computational efficiency than conventional numerical methods.

Structural behaviour of post-earthquake steel plate shear wall repaired by non-welded oblique stiffeners

A two-stage experimental study was conducted to investigate the structural behaviour of two single-span two-storey steel plate shear wall (SPSW) specimens repaired by non-welded oblique stiffeners. In stage Ⅰ, both SPSW specimens were subjected to a quasi-static load to simulate the damage under an earthquake attack. Afterwards, the infill panels in one SPSW specimen were repaired and stiffened by non-welded oblique stiffeners (i.e., specimen OR-SPSW). The damaged SPSW specimens with or without repair were subjected to cyclic load to evaluate the effectiveness of the repair method in stage II. The seismic performance of two SPSW specimens was compared in terms of initial stiffness, bearing capacity, energy dissipation capacity and out-of-plane deformation of infill panels. Test results indicate that the residual out-of-plane deformations of infill panels were effectively restrained after the installation of oblique channel steel. The bearing capacity of specimen OR-SPSW was 11.06% higher than that without repair. In addition, the finite element analysis was performed to further investigate the seismic performance of the SPSW structures repaired by various types of stiffeners, including oblique multi ribs, orthogonal and oblique channel steel. The simulation results indicate that using the three types of stiffeners is able to restore the seismic behaviour of SPSW structures, while using the oblique multi-rib stiffeners is the most effective method in restraining the out-of-plane deformation of infill panels and increasing the bearing capacity. However, the orthogonal channel steel stiffener can contribute to little enhancement of the structural bearing capacity. Besides, the bearing capacity of the SPSW structure repaired by the oblique multi-rib stiffeners was 14.29% higher than that with the oblique channel steel stiffeners.

Loading protocols for seismic qualification of steel plate shear walls

As a new type of lateral force resisting member, steel plate shear walls (SPSWs) have the advantages of excellent energy dissipation, high lateral stiffness, and ductility. Owing to the lack of loading characteristics of an actual earthquake in the existing loading protocol of SPSWs, the interpretation of the seismic performance of SPSWs is still challenging. A set of standardized loading protocols for SPSWs under far-field and near-fault earthquakes were proposed, to replicate the real loading histories in severe earthquakes. By using the rainflow counting method, the seismic parameters (such as damage cycle, interstory drift range, and residual interstory drift) from four frame–SPSW structures subjected to a series of representative ground motions, were analyzed to develop the loading protocols. Moreover, the rationality of the proposed loading protocols was discussed and verified by demonstrating the cumulative distribution function and energy dissipation of these protocols. It is well illustrated that the proposed protocols can truly simulate the loading history of members and accurately reflect the seismic damage demands in the inelastic stage.

Assessment of damage index and seismic performance of steel plate shear wall (SPSW) system

Nowadays, the discussion of prevention and reduction of earthquake hazards and the introduction of methods to assess the vulnerability of structures has become very important. This study aims to investigate the failure distribution and assess the seismic behavior of a steel shear wall (SPSW) system quantitatively. Therefore, to assess the failure distribution of SPSW structures in the 4, 8, and 12-floors has been designed and analyzed. The studied structures have been analyzed under 24 far-field earthquakes in the time history analysis section. Three damage indicators of Park and Ang, Iemura and Mikami, and relative displacement were used to investigate the failure's extent and location. The average failures of all three indicators are examined to evaluate the performance levels of structures. The results show that a significant part of the floors for the relative displacement index is limited to life safety. Also, Park and Ang's and Iemura and Mikami's indices are limited to damage control. According to the results, the most damage is observed in 4-story frames. There is also damage to 8- and 12-story frames, but the amount is small. On the other hand, the evaluation of failure indices and performance levels estimates the structure's safety in terms of seismic design. Also, examining the seismic behavior of structures based on damage indices Park and Ang and Iemura and Mikami provides a more realistic amount of damage and performance levels of structures for designers.

Performance of repaired steel plate shear wall with earthquake-induced damage

To investigate the repair method of damaged steel plate shear wall in a steel frame, a scaled specimen was designed and tested under a two-phase pseudo-static loading. The damaged infilled steel plates were replaced with new steel plates between the two loading phases. The test results showed that after replacing the damaged infilled plates, the stiffness of the specimen increased. The bearing capacity was 577.3 kN, with a ductility of 3.5. The seismic performance of the repaired specimen was favorable. Replacing the infilled plate was an effective repair method for the steel plate shear wall structure while the columns were still in good integrity. To ensure a reliable post-earthquake performance of the boundary frame and an easy repair for the steel plate shear wall, the plastic development of the boundary column was investigate. By introducing the damage criterion into the finite element (FE) model, the stress redistribution caused by the damage of the infilled steel plate was considered. The shear force of the column at different lateral displacement, especially in the inelastic phase, was obtained. The yielding and damage state of the boundary column can be determined from the proportion of sustained shear force of the column at different displacements.

Experimental and numerical investigation of cross-shaped buckling-restrained SPSWs with composite structure

The square concrete-filled steel tube (CFST) column enjoys the advantages of high bearing capacity, a simple structure of beam-column joints, good ductility and seismic performance. Therefore, the square CFST columns are introduced as the boundary frame of buckling-restrained steel plate shear wall (SPSW). To investigate the cyclic behaviour of cross-shaped buckling-restrained SPSW with a composite frame consisting of H-shaped steel beams and square CFST columns, two specimens were prepared and tested under the cyclic quasi-static loading, and the failure modes and hysteretic curves of the specimens were discussed. Experimental results show that the cross-shaped buckling-restrained stiffeners can significantly reduce the out-of-plane deformation of the steel plate and improve the bearing capacity of SPSW structures. The finite element (FE) models of SPSWs with cross-shaped stiffeners were developed, and good agreement was observed between the FE analysis results and test results for the failure modes, skeleton curves and bearing capacity. Based on the parameter analysis results of the cross-shaped buckling-restrained SPSWs structures, it is assumed that the strength of the embedded steel plate can be fully exerted when the flexibility coefficient of square CFST columns is no greater than 2.5. In addition, the design rules of the flexibility coefficient of square CFST columns were proposed to promote the application of SPSW buckling-restrained by cross-shaped stiffeners in high-rise buildings.

Mechanical performance of coupled buckling-restrained steel plate shear walls

In order to improve the seismic behavior of coupled steel plate shear wall (CSPSW), a new type of coupled buckling-restrained steel plate shear wall structure is proposed. To study the mechanical characteristics of coupled buckling-restrained steel plate shear wall (CBRSPSW), calculating equations for coupling degree of this novel coupled shear wall is derived. The finite element software ABAQUS is used to conduct the parametric studies on the FE models of CBRSPSW and CSPSW. Besides, the ratio of the plastic sectional bending resistances of coupling beam and frame beam γ was selected as the main parameters to control the coupling degree. The mechanical properties of CBRSPSW and CSPSW, like failure mode, shear distribution, column internal force and coupling beam rotation, are analyzed and compared. Besides, the influences of the beam plastic moment ratio γ on the these properties are also studied. Through the numerical research, the coupling degree of CBRSPSW and CSPSW is recommended to be controlled within 0.35–0.45 so that rational mechanical behavior can be obtained.