Quasi-static experiments on steel plate shear walls reinforced with X-shaped restrainers

doi:10.1016/j.jobe.2020.101451

Journal of Building Engineering

Volume 31, September 2020, 101451

https://doi.org/10.1016/j.jobe.2020.101451 Get rights and content

Highlights

•
A novel buckling restrained steel plate shear wall with X-shaped restrainers (XSPSW) is proposed.
•
The quasi-static experiment on unstiffened steel plate shear wall (USPSWs) and XSPSWs were conducted.
•
The mechanical properties and energy dissipation capacity of the XSPSW were obtained.
•
The failure mechanism of the XSPSW under a cyclic load was revealed, and the rationality of the XSPSW was verified.
•
The SPSWs with small height-to-thickness ratio of the infill steel plate exhibited relatively stable hysteretic behavior.

Abstract

Steel plate shear walls in this paper consist of X-shaped restrainers, embedded steel plates and boundary restrainers (simply referred to as XSPSW). The XSPSW was constrained by sliding X-shaped restrainers. The embedded steel plate was divided into diagonally arranged square sub-plates with small height-to-thickness ratio by X-shaped restrainers set on two sides of the embedded steel plate. Shear buckling of the plate can effectively be constrained, and the seismic energy dissipation capacity of the SPSW can be increased. Moreover, because the external X-shaped restrainers have characteristics of rapid assembly and high stiffness, they can be reused after a rare earthquake. Four groups of quasi-static experiments on unreinforced steel plate shear walls (USPSWs) and XSPSWs were conducted to obtain their mechanical properties and energy dissipation capacity. The failure mechanism of the XSPSW under cyclic load was revealed, and the rationality of the XSPSW was verified. Experimental results showed that the initial stiffness, load-carrying capacity, and energy dissipation capacity of the XSPSWs were at least 21%, 11%, and 27%, respectively, higher than those of the USPSW. For USPSWs, the embedded steel plate with a small height-to-thickness ratio exhibited relatively stable hysteretic performance. The height-to-thickness ratio of the subplate is the main factor affecting the hysteretic performance of the XSPSW. Meanwhile, the X-shaped restrainers were not damaged during the experiment and could be reused.

Introduction

The steel plate shear wall is an effective lateral-force resisting structural component that was developed in the 1970s. It consist of a embedded steel plate, horizontal and vertical boundary restrainer. SPSWs resist wind, earthquakes, and other lateral loads by forming an inclined tensile field after the shear buckling of the embedded steel plate [[1], [2], [3]]. Berman, through cyclic loading experiments, found that SPSWs exhibited good ductility and seismic behavior [4,5].

In early applications, thicker or welded reinforced steel plates were used to prevent out-of-plane buckling of the embedded steel plate before the shear yield [6]. Since the early 1980s, the ultimate state of the SPSW in the norms of the United States, Canada, and other countries has been the yield of the diagonal tension band formed after the buckling of the embedded steel plate [7,8]. Therefore, a thinner embedded steel plate could be selected to meet the requirements of structural stiffness and load-carrying capacity. Under relatively small shear loads, a embedded steel plate of thin, unreinforced SPSW will produce significant out-of-plane plastic deformation and buckling noise.

To improve the energy dissipation capacity of the SPSWs and the performance of the structure, an approach of setting a stiffener or concrete panel was put forward to restrain the shear buckling of the thin SPSW or to reduce its out-of-plane buckling deformation [[9], [10], [11], [12]]. However, stiffeners welded to steel plates do not provide continuous, stable out-of-plane constraints for the embedded steel plate, and result in additional costs. Moreover, too many stiffeners will affect the deformation performance of the SPSW [9,13]. Placing concrete plates on two sides of an embedded steel plate can effectively restrain buckling and help the steel plate resist horizontal loads through in-plane shear [14], but this approach will significantly increase the weight and construction period of the structure and reduce the load-carrying capacity of the structure suddenly [15].

In order to effectively constraint the shear buckling of the embedded steel plate and improve the energy dissipation capacity and service performance of the SPSWs, the advantages of the rapid industrial production and assembly construction of an all-steel structure should be completely utilise. Thus, a new SPSW reinforced with the X-shaped restrainer and its design method were proposed in the literature [16]. The restrainers improve the seismic performance of the SPSWs effectively by divid the plate into squre sub-plates which have well buckling behavior. The embedded steel plate connect with X-shaped restrainers by the pull bolt, and the underboardings are used to install bolts (Fig. 1(a)).

The X-shaped restrainers consist of steel tubes and connection boxes (Fig. 1(b)), and the diameters of the expanded bolt holes are larger than those of the bolts, to ensure that the bolt rod does not contact with the hole wall during the large earthquake. The restrainers is sliding within a certain range relative to the embedded steel plate. The size of the clearance is the ultimate storey drift angle (1/50) of the height of embedded steel plate under rare earthquakes [17]. Moreover, the external X-shaped restrainers have the characteristics of rapid assembly and high stiffness, so they can be reused after the strong motion.

In this study, a quasi-static method was used to carry out a low-cycle cyclic load experiment on USPSW and XSPSW scale-model specimens. The hysteretic performance and failure modes of the two types of SPSWs were compared, and the working mechanisms and energy dissipation capacities were revealed. The initial stiffness and variation rules of the peak loads of the SPSWs were obtained, and the rationality of the buckling restraint effect of the X-shaped restrainers was verified.

Section snippets

Specimen design and fabrication

Four single-layer and single-span hinged frame specimens were designed. The specimens were squre with a dimension of 1500 mm. To study the hysteretic performance of specimens with different height-to-thickness ratios of the embedded steel plate, two groups of embedded steel plates with thicknesses of 4 mm and 2 mm were selected, and the corresponding height-to-thickness ratios were 375 and 750. The specimen parameters are listed in Table 1.

Note: λ and λ_sub are the height-to-thickness ratios of

Phenomenon of USPSWs

Fig. 7 and Fig. 8 show the out-of-plane displacement curves and entire failure modes of the USPSWs respectively. The specimen of USPSW1 yielded when the load was ±328 kN, the steel plate evidently buckled and the displacement was 13.7 mm. Before the yield point, the specimens were basically in the elastic stage and the trends of out-of-plane displacement for each measured point were similar, indicating that the specimen occurred low-order single-wave buckling. In the displacement loading stage,

Strain response

The strain development process of the embedded steel plate was measured during the experiment. The strain–load curves, with obvious changes in the embedded steel plate, are shown in Fig. 11 (USPSW) and Fig. 12 (XSPSW). Before USPSW1 yielded, the strains of most measured points were small. In the displacement loading stage, the strains (5, 10, 15, 20, 25) in the principle diagonal region of the loading direction increased rapidly and exceeded the yield strain of the steel, indicating that the

Numerical analysis

The numerical analysis method established in Ref. [19] was used to model the USPSW and XSPSW specimens in the test and applied the same loading protocol, the results are shown in Fig. 21. Due to the relative slip between the specimen and loading frame in the experiment, the hysteretic curves obtained by the numerical analysis are slightly fuller. However, the differentials of their peak load are all smaller than 5%.

When the height-to-thickness ratio of the embedded steel plate (λ) is 200 and

Conclusion

This experimental study examined SPSW specimens under a low-cycle cyclic load. Some of the conclusions drawn are as follows.

(1)
The USPSW was easy to buckle, and was accompanied by significant noise. The elastic-plastic out-of-plane buckling of the embedded steel plate was obvious, and the hysteresis curve was seriously pinched. Moreover, the out-of-plane buckling of the embedded steel plate resulted in a significant reduction in the energy dissipation capacity of the shear walls.
(2)
X-shaped

CRediT authorship contribution statement

Zhenggang Cao: Writing - review & editing. Zhicheng Wang: Writing - original draft. Peng Du: Data curation. Han Liu: Visualization. Feng Fan: Funding acquisition.

Declaration of competing interest

There are no conflict of interest exits in the submission of this manuscript, and manuscript is approved by all authors for publication. “Quasi-static experiments on steel plate shear walls reinforced with X-shaped restrainers”.

Acknowledgements

This work was conducted with financial support from the Chinese National Natural Science Foundation (Project designation: 51878218).

References (19)

J.W. Berman et al.
Comparing hysteretic behavior of light-gauge steel plate shear walls and braced frames
Eng. Struct.
(2005)
J.W. Berman
Seismic behavior of code designed steel plate shear walls
Eng. Struct.
(2011)
M.M. Alinia et al.
Cyclic behaviour, deformability and rigidity of stiffened steel shear panels
J. Constr. Steel Res.
(2007)
H. Guo et al.
Behavior of stiffened and unstiffened steel plate shear walls considering joint properties
Thin-Walled Struct.
(2015)
M.M. Alinia et al.
On the design of stiffeners in steel plate shear walls
J. Constr. Steel Res.
(2009)
Zhenggang Cao et al.
Research on steel plate shear walls stiffened with X-shaped restrainers: hysteretic behavior and effect of height-to-thickness ratio of steel plate
Thin-Walled Struct.
(2019)
C. Li et al.
Cyclic tests of four two-story narrow steel plate shear walls. Part 2: experimental results and design implications
Earthq. Eng. Struct. Dynam.
(2010)
L.J. Thorburn et al.
Analysis of Steel Plate Shear Walls
(1983)
K. Tsai et al.
Cyclic tests of four two-story narrow steel plate shear walls—Part 1: analytical studies and specimen design
Earthq. Eng. Struct. Dynam.
(2010)

There are more references available in the full text version of this article.

Cited by (11)

Experimental and numerical investigation of a new type of steel plate shear wall with diagonal tension field guiding stiffeners
2023, Journal of Building Engineering
A novel type of steel plate shear wall for withstanding lateral forces was proposed. Inclined stiffeners (acting as tension field guiding stiffeners) were added at the corners of the shear wall and a middle link beam was created, similar to the eccentrically braced frames (EBF). Therefore, upon adding diagonal members to the shear wall, the system resembled a combination of a steel plate shear wall system with an EBF system.
To study the cyclic performance of the system equipped with the guiding stiffeners, a scaled specimen of the shear wall was made and subjected to cyclic loading. Finite element model of the wall was simulated and validated using the corresponding laboratory data. Then, a comparison between the proposed shear wall and the corresponding unstiffened steel plate shear wall was made. In the proposed system, the guiding stiffeners can alter the pattern of the tension field, pushing away the plastic strains from the column face toward the link beam. This helps the columns and connections remain intact. As a result, the system failure mechanism includes two-stage ductile fuses, including the steel plate yielding in tension, and flexural stresses or shear plastic hinges at the link beam ends. Compared to the unstiffened steel shear wall, the fuses help dissipate more energy in the proposed shear wall. In general, diagonal tension field guiding stiffeners can enhance the lateral force capacity, ductility, energy absorption, and stiffness of the system simultaneously.
Structural failure assessment system exemplified by dumbbell-shaped CFST arch
2023, Engineering Structures
The study of structural failure law is the basis of structural safety assessment, but engineering structures present complex nonlinearities and diversity, which make it difficult to analyze the failure laws of structures. However, the failure of ductile structure is a process of quantitative cumulation to qualitative change, and this turning point is the key to structural failure analysis. Based on this view, we propose a new system for structural failure assessment, which includes the identification of mutation locations, strain data visualization, structural internal force estimation, and finite element stochastic simulation, etc. Moreover, every new method is compared and validated. Experimental data of a dumbbell CFST arch model are used throughout the paper for illustration. Finally, the time-varying failure probability of the whole structure is evaluated. In summary, this paper organically combines experiment, simulation and engineering practice to provide a new approach to structural safety analysis, structural health monitoring and structural design.
Numerical investigation of transverse steel damper (TSD) seismic system for suspension bridges considering pounding between girder and towers
2022, Soil Dynamics and Earthquake Engineering
Citation Excerpt :
Fig. 1 shows a girder-support connection system in which the TSD system controls the transverse horizontal behavior while the sliding bearings support the vertical loads of the suspended superstructure. The developments of TSD in bridges were pursued to a simple and reliable transverse seismic-control system that exhibits superior seismic behavior comparable to mature damper systems employed in buildings [34–36]. The detailed configuration of the TSD is illustrated in Fig. 2.
Transverse steel damper (TSD) is a promising passive control device used for seismic isolation and has been validated to feasibly balance the girder transverse seismic displacement and inertial force in cable-stayed bridges. However, for the TSD system, transverse pounding could occur at the locations of girder and tower legs when the gap size is insufficient to accommodate the girder-support transverse relative displacement under major earthquakes. Transverse pounding can significantly affect the dynamic responses of bridge structures, hence, the present paper investigates the effectiveness of TSD as a control strategy for transverse seismic responses in long-span bridge structures (i.e., suspension bridges), accounting also for the influence of the pounding effect in the dynamic response analysis. A typical suspension bridge is considered for case study purposes, and four transverse girder-support connection systems are investigated, including the conventional fixed and sliding-free connections and the TSD connections with and without pounding effect. A comprehensive comparison of the seismic performance among these transverse restraining systems is conducted through Incremental Dynamic Analysis and fragility analysis. Additionally, the effect of seismic-induced pounding in the TSD system is assessed from an energetic point of view. The results show that, for the suspension bridge with TSDs as the transverse control strategy, a satisfactory balance between force and displacement demands can be obtained in small-to medium-intensity earthquakes. However, the pounding between the girder and tower legs during large-intensity earthquakes can substantially increase the seismic demands in the tower legs.
Development of a volumetric compression restrainer for structures subjected to vibration
2022, Journal of Building Engineering
Citation Excerpt :
As a sample of such works, Dehghani and Tremblay [22] worked to obtain a proper design for the restraining mechanism. Steel plate shear walls consist of X-shaped restrainers have been analyzed through Quasi-static experiments to evaluate their mechanical properties and energy dissipation capacity [23]. The results of the analysis showed that the height-to-thickness ratio is a main factor to affect the performance and a small height-to-thickness ratio exhibited relatively stable hysteretic performance.
In the last 2 decades, application of viscous dampers as restrainer device (lock-up) in buildings and bridges to diminish harmful effect of vibrations. However, leakage issue in the viscous luck-up devices requires regular expensive maintenance procedure to prevent device performance failure and many researchers are encouraged to find an alternative system with low maintenance cost. Therefore, in this study the Volumetric Compression Restrainer (VCR) device has been developed as a new effective restrainer system using hyper-elastic rubber material. The VCR device is consisted of multi hyperelastic rubber tubes which positioned within steel cylinder with core and applicable in the structures as vibration resistance system. To develop VCR device, the primary design details are derived and the behavior of proposed VCR subjected to various dynamic load conditions has been assessed through the finite element simulation. In order to define the hyper-elastic characteristics of the rubber material for finite element modeling, the hyperelastic rubber material with 3 different hardness properties have been tested experimentally. Then in the next step, the rubber test data were used to develop the analytical model for the VCR device. So, the performance of the VCR device was determined by applying cyclic load to the developed FEM model. Afterwards, multiple prototypes of VCR devices have been manufactured with four different rubber hardness properties and two different configurations and a series of experimental tests have been conducted to validate the device performance.
Then, a three-story concrete frame equipped with supplementary VCR device subjected to seismic loads is considered and the performance of VCR and its efficiency to diminish vibration effect are evaluated. Besides, the hybrid population-based algorithm (PSOGSA) is implemented to optimize design of structure equipped with VCR device under applied earthquake excitation. The results revealed that by implementing VCR device as supplementary restrainer system in the frame structure, lateral displacement is reduced in range of 31.5–61.2% compared to the bare structures which is proving the efficiency of developed VCR device to protect the structures against severer dynamic loads.
Mechanical performance of coupled buckling-restrained steel plate shear walls
2021, Journal of Building Engineering
Citation Excerpt :
Different from conventional composite SPSW [14,15], SPSWs with buckling-restraining concrete panel use concrete panel only to realize buckling restraint, reserved holes on the concrete panel and gaps between the concrete panel and boundary frame elements make the concrete panel relieve from in-plane shear transferring and prevent the crack or failure of the concrete panel. Based on the design criterion of concrete panel buckling-restrained steel plate shear wall, other non-welded and shear-free restrainers made of other materials, such as steel, were all proved to be effective shear wall structures [16–19]. Among these schemes for performance improving of traditional thin steel plate shear wall, buckling-restrained steel plate shear wall, using reinforced concrete panels to restrain the out-of-plane deformation of infill thin steel plate, is one of the most effect structural forms and proved to have higher bearing capacity, larger lateral stiffness, higher energy consuming capacity.
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.
A study on mid-panel of steel shear-walls with dual openings
2021, Journal of Constructional Steel Research
Citation Excerpt :
They found that a rigid beam-column connection can improve the performance and the capacity of the walls from 5% to 35%. Cao et al. [7] conducted a set of experiments under quasi static loading on steel shear-walls with X-shaped restraints. They showed that the initial stiffness, capacity, and energy dissipation of reinforced walls are higher respectively by about 21%, 11%, and 27% than unreinforced shear-walls.
The presence of openings in steel shear-walls is oftentimes necessary due to different design requirements. This paper investigates the behaviour of a panel in between two openings (mid-panel or MP) in shear-walls with dual openings under monotonic loading. The panel is analogised to link-beams in eccentrically-braced frames. To examine the structural response of these structures, two established conditions (elastic force and displacement) are addressed. Theoretical formulations are developed for a new condition (flexural stiffness of stiffeners to shear stiffness of a plate) in addition to the two conditions above. Furthermore, an equation was derived to calculate the shape factor of sections with box-shaped flanges, which is used to obtain the shear displacement (yield) of the mid-panel's plate. A comprehensive parametric study (44 models) is conducted using Finite Element Analysis (FEA) to examine the effect of six different geometric factors on the structural response of the mid-panel. The mid-panel's dominant structural responses (deformation and stress distribution) are classified as (i) flexural, (ii) shear, and (iii) combined (shear-flexure). The increase of the MP's width, the box-stiffeners' web height, flange's width and thickness causes a shear response, while the increase of the MP's height and the thickness leads to a flexural behaviour. Each structural response is carefully addressed theoretically and numerically leading to consistent results. The variables of the MP's plate bring about higher effects on the behaviour of the MP comparing to the parameters of the stiffeners. Overall, a shear response is structurally desirable, which enhances the MP's energy dissipation and post-buckling capacity.

View all citing articles on Scopus

View full text