Composite Shear Walls Research Articles

Seismic performance of thin-walled steel and concrete composite column-corrugated steel shear wall structure

This paper presents a new structure called cold-formed thin-walled channel steel and concrete composite column-corrugated steel shear wall (referred to as CSC-CSW), which can significantly improve the lateral resistance of SPSW. Three groups of full-length walls were tested under low-cycle reciprocating loading in order to investigate the effects of axial compression ratio and aspect ratio of steel plates. The experiment discovered that the failure of specimens was mainly caused by the tear of corrugated steel plate and the bearing failure of bolt hole. The results show that with the increase of the axial compression ratio, the average peak bearing capacity, ductility and ultimate displacement are decreased. With the decrease of the aspect ratio of the steel plate, the shear capacity and initial stiffness of the specimen are decreased, but the ductility and energy dissipation capacity are improved. On the basis of the test, 19 refined FEA models were established to carry out the multi-parameter analysis. The influence rule of the parameters is revealed and the reasonable value range is given, namely. The thickness of channel steel ranges from 1.5 mm to 2.5 mm, the thickness of corrugated steel plate ranges from 1.5 mm to 2.5 mm and the aspect ratio goes from 0.8 to 1.2, and the axial compression ratio of frame column should not exceed 0.3. Finally, the shear-carrying calculation formula is proposed, and the reliability of the formula is verified by comparing formula calculation results with FEA results, whose maximum error is within 15%.

Seismic behavior of steel plate concrete composite shear walls with PEC columns and WRGs

An innovative shear wall was proposed by introducing partially encased composite (PEC) columns and welded reinforcement grids (WRGs) into steel plate concrete composite shear wall. This work conducted an experimental investigation of the seismic behavior of seven 1/3-scale proposed walls subjected to cyclic lateral loading. The design parameters included the forms of distribution reinforcement, axial compression ratio, thickness of the built-in steel plate, shear-to-span ratio and thickness of the PEC column-section steel flanges. The results revealed that the specimens had good bearing capacity, deformation ability, energy dissipation capacity, and stiffness under a reasonable axial compression ratio. Compared with a specimen featuring orthogonal distribution reinforcement, the cracking load and ductility of a specimen with diagonal cross-distribution reinforcement were increased by 6.5% and 13.6%, respectively. And increasing the thickness of the built-in steel plate and the PEC column-section steel flanges could augment the bearing capacity and ensure the late stiffness of the specimens. Then, the residual displacement fitting formulae were presented herein to assess post-earthquake repairability. Besides, the bearing capacity calculation formulae of the novel shear wall with certain prediction accuracy were proposed. Finally, finite element models of the tested specimens were established in ABAQUS and validated with experimental results. Also, further investigations regarding the influence of axial compression ratio and shear-to-span ratio were implemented by finite element analysis and engineering recommendations for the designed axial compression ratio limits of the novel shear were given.

Study on the Seismic Behavior of a Steel Plate–Concrete Composite Shear Wall with a Fishplate Connection

The steel plate–concrete composite shear wall (SPCSW), having been widely applied to several super high-rise buildings, is currently regarded as a new type of lateral load-resisting structure. The SPCSW design does not consider the connection to the surrounding structure, normally envisaged as a buttweld connection, while the fishplate lap connection tends to be applied in construction. To explore the fishplate lap connection to achieve the performance standard of SPCSW, in this paper, an SPCSW with a fishplate connection is modeled using ABAQUS to investigate the hysteretic behavior under constant axial force and horizontal cyclic loads. Through the hysteresis curve and a load–displacement skeleton curve, the effects of fishplate thickness and lap length on its hysteretic behavior are studied. The results show that increasing the fishplate thickness contributes to a slight increase in the bearing capacity and energy dissipation and has little influence on stiffness degradation. When the fishplate thickness is more than half the steel plate thickness, the strength and energy dissipation of an SPCSW with a fishplate connection can reach the level of an SPCSW without a fishplate connection. The bearing capacity and stiffness of the SPCSW increase with the increase in lap length. When the lap length is greater than 50 mm, the strength, stiffness and energy dissipation capacity of an SPCSW with a fishplate connection are superior to those without fishplate connections. Finally, engineering suggestions on fishplate connections are put forward.

Seismic analysis and connection optimization of the side column on modular prefabricated four‐sided connected composite shear wall

SummaryA modular prefabricated four‐side connected composite (MPFC) shear wall that consists of a composite shear wall modular (CSWM) and steel frame boundary elements is proposed. First, the finite element model (FEM) of the MPFC shear wall, which considers a plastic‐damage constitutive model of both concrete and steel materials, is established based on the finite‐element software ABAQUS. Second, the FEM accuracy of the MPFC shear wall is verified by the experimental results of a modular prefabricated two‐sided connected buckling‐restrained (MTB) steel plate shear wall. Third, the seismic performance of the MPFC shear wall is investigated based on the verified FEM. The connection between the CSWM and side column is optimized. Finally, the initial stiffness calculation formula of the MPFC shear wall that considers the impact of that the thickness ratio between the connection steel plate (CSP) and inner steel plate (ISP) is deduced. The results show that the peak bearing capacity, initial stiffness, total energy, and total strain energy of the MPFC shear wall increased by 42.47%, 44.81%, 113.24%, and 58.97%, respectively, compared with those of the MTB steel plate shear wall. The compressive corner damage of the reinforcement concrete faceplate (RCF) of the MPFC shear wall with a side column and CSWM is connected by a middle steel plate is effectively improved. Compared with those of the MPFC shear wall in which the side column and CSWM are connected by bolts, the shearing force, axial force, and bending moment of the side column of the MPFC shear wall in which the side column and CSWM are connected by the middle steel plate are notably decreased by 25.32%, 26.08%, and 39.51%, respectively. The FEM results are compared with the formula calculation results to establish its accuracy in calculating the initial stiffness of the MPFC shear wall.

Experimental and numerical study on the shear lag behavior of l-shaped double-steel-plate composite shear wall

The shear lag behavior significantly affects the stress distribution of structural members, and ignorance of the shear lag behavior may cause serious engineering accidents. This work shows the shear lag behavior of two l-shaped double-steel-plate concrete composite shear wall (LDSCW) specimens (one with a wide flange and one with a narrow flange) under cyclic loading experimentally investigated. All specimens failed by the local buckling of the steel plate and concrete crushing. The LDSCW shows a good ability to dissipate energy, and the LDSCW with larger flange width exhibits better carrying capacity. The shear lag behavior is serious on the flange of the LDSCW. A finite-element (FE) model is developed to investigate the shear lag behavior of the LDSCW. It is concluded that the influences of the axial compression ratio and the height-width ratio of the flange of the LDSCW on the shear lag effect are significant. Models for predicting the effective flange width (EFW) of LDSCW in the Plastic Stage and Elastic Stage, which make good agreement with experimental results, are developed. The results of this work can provide a reference for the design of the LDSCW.

Boundary plate influence on tie bars axial force demands in composite plate shear walls‒concrete filled

In composite plate shear walls–concrete filled (C-PSW/CF), there is an indeterminate flow of force between concrete, steel plate and tie bars. Finite element methods (FEM) are frequently used to verify this force flow. The theoretical models available in the literature to predict the tie bar maximum axial force demands were based on walls without boundary plates. The finding in this study is intended to help understand whether current theoretical approaches are conservative and can be applied to boundary plate walls as well. Within the scope of this study, tie bar axial force demands for walls with boundary plates consisting of planar and round shapes and without boundary plates were investigated and compared. For this, a previously benchmarked finite element (FE) wall model was considered and configured to have no boundary plate and have planar and round boundary plates. FE models were analyzed under monotonic lateral displacement up to 4% drift ratio. Passive lateral pressures and transverse force variations on the planar and round boundary plates were investigated.

Seismic behavior of steel truss and concrete composite shear wall with double X-shaped braces

Aiming to enhance the seismic performance and assembly of reinforced concrete (RC) shear walls, a novel steel truss and concrete composite (STCC) shear wall with twin X-shaped braces are proposed. Four STCC shear walls and one RC shear wall were tested under cyclic lateral and constant axial load to determine the effect of the number of channel columns and the addition of a crossbar on the seismic performance of STCC walls, as well as the difference in the seismic performance between the STCC wall and RC wall. Based on the test results, an optimal truss design is presented. Additionally, a comprehensive parametric analysis was carried out on 27 finite element models to investigate the influence of critical factors, such as the axial load ratio, the steel ratio of embedded steel columns, and the volumetric ratio of embedded braces, on the seismic performance of STCC walls. Results indicated that the ductility and the energy dissipation of the STCC shear walls were significantly improved, consequently reducing the number and extension of concrete cracks. Double channel columns could improve the bearing capacity of the STCC walls and provide sufficient support for X-shaped braces. Moreover, adding a crossbar could reduce the stiffness and bearing capacity degradation rate of the wall, but strengthening the connection between the column and the reinforcement inside the bottom foundation is recommended. The axial load ratio and the steel ratio of channel columns had more significant influence on the bearing capacity of STCC walls than the volumetric ratio of embedded braces. Finally, a calculation method is proposed, and the calculated results are in good agreement with the test findings.

Seismic behavior and design of PEC shear wall with replaceable corner components

Partially encased composite(PEC) shear wall is a novel lateral-force resisting system, with the section consisted of two thin-walled H-section PEC column, middle vertically-stiffened steel plate, links between the flanges and concrete partially encased in the hollow region. To improve the energy dissipating capacity and facilitate the post-earthquake repair, this paper presents using replaceable energy dissipaters in the footings of PEC shear wall to construct a resilient PEC(RPEC) shear wall. Based on the design criterion of equivalent strength, the design method for RPEC shear wall is proposed. According to this design method, several full-scale single-storey PEC and RPEC shear walls were designed and numerically studied through finite element analyses. The influences of width-to-thickness ratio, axial force ratio, shear-span ratio, and cell number on the bearing capacity, initial stiffness and failure mode were studied. Moreover, the hysteretic behavior of PEC and RPEC shear were also compared to verify the design method. It was found that the proposed RPEC shear walls can well mitigate the damage to the wall limb. Compared with the results of simulation, the initial stiffness and ultimate bearing capacity of both PEC and RPEC shear wall, obtained by the calculating equation, are conservative and reasonable. The RPEC shear wall designed based on the equivalent-strength design criterion of PEC shear wall can better restrain the stiffness degradation. However, the energy dissipation capacity of the RPEC shear wall is slightly weakened. Generally, this research can provide reference for the practical application of RPEC shear wall.

Numerical analysis of CFST-RC composite shear wall under axial compression and cyclic loads

The concrete-filled steel tube reinforced concrete (CFST-RC) composite shear wall is a new structure utilising the advantages of a reinforced concrete shear wall and CFST column. The finite element (FE) model for CFST-RC shear walls was validated by experimentation. Under the axial compression and cyclic loads, the mechanical properties were studied by changing the structure and material. Numerical simulation results indicate that compared with the concrete inside the tube, the concrete outside the tube can better limit the deformation of the steel tube, so it significantly affects the axial compression performance. Compared with the concrete, the steel tubes can effectively improve the seismic performance. However, when the steel content and steel tube strength increase to a certain value, the seismic performance decreases due to the synergistic effect of the concrete and the steel tube. Finally, a simple method for calculating the elastic modulus of shear walls is proposed based on the theory of composite materials. From the FE simulation results, the influencing factors of axial compression and seismic performance of CFST-RC shear walls with different parameters were also analysed, which can provide technical support for the design of shear walls and their safe application in practical engineering.

Nonlinear modeling for composite plate shear walls-concrete filled structures

This paper proposes modeling recommendations, including constitutive model parameters for concrete and steel for nonlinear and macroscopic simulation of Composite Plate Shear Walls-Concrete Filled (C-PSW/CF) structures. Predictive equations are developed to determine the constitutive models of confined and unconfined concrete and steel faceplates, considering the buckling and fracture effects. A comprehensive database consisting of the test results of 37 C-PSW/CF specimens with and without endplates and boundary elements is collected and used to assess the required constitutive model parameters. Based on the validated macro model, predictive equations for backbone curves of unconfined and confined concrete and steel faceplates are proposed, all having high accuracy (R2 values larger than 0.9). The proposed modeling recommendations and constitutive models are further validated using a wide range of finite element analyses performed on prototype composite shear walls under monotonic loading. The proposed equations and modeling recommendations efficiently simulate the seismic behavior of C-PSW/CF structures with aspect ratios larger than or equal to 1.

Fire resistance of composite shear walls filled with demolished concrete lumps and self-compacting concrete

The recycling and reuse of waste concrete is conducive to promoting the sustainable development of resources and practicing the concept of green development. Demolished concrete lumps (DCLs) and self-compacting concrete (SCC) made from waste concrete take full advantage of their recyclability. In order to fully utilize the advantages of demolished concrete lumps and self-compacting concrete in construction, applying demolished concrete lumps and self-compacting concrete to composite shear wall structures is an effective way to reduce costs and improve industrial production. In this paper, a new composite shear wall filled with demolished concrete lumps and self-compacting concrete is proposed, and its fire performance is investigated. The shear wall combines edge constraints of concrete-filled steel tubes, demolished concrete lumps and self-compacting concrete. In order to facilitate the mass pouring of demolished concrete lumps, a cavity is formed between the steel tubes at the ends and the precast walls on both sides. A double-sided fire tests was conducted on three composite shear wall specimens filled with demolished concrete lumps and self-compacting concrete at a constant axial compression ratio, where the fire-retardant coating and the wall width-to-depth ratio were considered as the main test parameters. The specimens were able to steadily withstand the predetermined axial loads during the fire resistance time of 180 min and showed good fire resistance. The concrete temperature variation trends of the three specimens in the wall section were basically the same. The fire-retardant coating on the concealed column had a significant effect on the section temperature of the steel tube, while increasing the wall width-to-depth ratio had little effect. When the axial compression ratio was 0.19, the specimens were in the expansion stage within 180 min and no compression occurred. The results show that the expansion deformation of the shear wall sprayed with fire-retardant coating on the outer surface of the concealed column is smaller than that of the shear wall without fire-retardant coating, and the axial deformation of the composite shear wall infilled with demolished concrete lumps and self-compacting concrete is not affected by increasing the wall width-to-depth ratio.

Investigating the Behavior of Composite Shear Walls with Corrugated Shape Memory Alloys Plate and Steel Fiber Concrete under Cyclic Loading

Investigating the Behavior of Composite Shear Walls with Corrugated Shape Memory Alloys Plate and Steel Fiber Concrete under Cyclic Loading

Performance of Composite Plate Shear Walls/Concrete Filled (C-PSW/CF) Under Fire Loading: A Numerical Investigation

Concrete-Filled Composite Plate Shear Walls (C-PSW/CF), also known as SpeedCore walls, are being increasingly used in commercial buildings due to the benefits of modularization and expedited construction schedules. This paper numerically investigates the behavior of C-PSW/CF subjected to combined gravity and fire loading. 3D non-linear inelastic finite element models of C-PSW/CF were developed and benchmarked to existing experimental data. The benchmarked models were used to understand the thermal and structural behavior of the walls under uniform fire loading, and to evaluate the effect of different parameters on the response of C-PSW/CF to combined gravity and fire loading. The parameters considered in the study were boundary conditions, wall slenderness ratio, wall thickness, axial load ratio, concrete strength, steel plate slenderness, steel reinforcement ratio, and tie bar spacing. Fire loading led to high surface (steel plate) temperatures, the evolution of non-linear thermal gradients through the cross-section, and progressive degradation of the material properties. The walls expanded longitudinally due to the thermal loads. The degradation in material properties resulted in local buckling of the steel plates between the tie bars. Continued fire exposure led to crushing/global instability failure of walls under gravity loads. The time to failure of the walls reduced considerably with a reduction in rotational fixity at the boundary conditions, reduction in wall thickness, and an increase in the wall slenderness. The steel plate slenderness of the walls should be limited to 1.2√Es/Fy to improve the time to failure of the walls. The results from this study will form a basis for the development of recommendations to estimate the fire-resistance rating and the compressive strength of the walls at elevated temperatures.

Nonlinear numerical modeling approach and seismic mechanism analysis on new modular precast composite shear wall structure

An innovative modular precast composite shear wall structure with the advantages of modular precast construction and demountable ability was proposed, and its seismic performance was validated by shaking table tests. This study aims to develop a nonlinear numerical modeling approach for the innovative modular precast structure to promote its engineering application. An equivalent energy method for the overall backbone of the concrete constitutive relationship was derived to consider the concrete stiffness reduction in the numerical model. Based on sectional analysis and plane section assumption, an explicit equivalent joint model was developed to simulate the nonlinear behavior and failure process of the vertical joints. Comparisons between the numerical and test results validated the ability of the numerical model to capture both the global and local responses. More detailed results that were hardly obtained by tests, such as displacement components, joint mechanical state and gap opening behavior, were extracted from the numerical analysis to reveal the seismic mechanism of the modular precast structure. The dynamic analysis results showed that the vertical joint deformation induced 10% to 14% of the total inter-story displacement at the first floor within the maximum considered earthquake intensity. The equivalent joint model could simulate the failure process of individual screws which exhibited larger strains than those in shear walls. The gap opening behavior induced additional energy dissipation mechanism for the modular precast structure.

Restoring Force Model for Composite-Shear Wall with Concealed Bracings in Steel-Tube Frame

Establishing a restoring force model is a fundamental yet critical task for the analysis of structural responses to earthquakes. Such a model has a substantial impact on the structural analysis results. Composite-shear walls with concealed bracings in steel-tube frames (composite-shear walls) offer several advantages, including convenient construction processes, high-bearing capacity, and excellent ductility. In this study, the mechanical properties of virtual test pieces were simulated when subjected to low-cyclic-reversed loading in ABAQUS. The simulation results agreed well with the experimental results. Subsequently, 24 additional virtual test pieces were obtained by adjusting the parameters of the original four test pieces, including the strength of the recycled concrete, thickness of the wallboard, and axial compression ratio. Finally, the restoring force model was validated using the experimental test results from our previous study. The results demonstrate the excellent performance of the proposed restoring force model in simulating the mechanical response of a composite shear wall. In particular, this model can accurately reflect the restoring force characteristics of the composite shear wall explored in this study. The restoring force model provides an effective theoretical support for the analysis of the elastoplastic seismic response of similar types of structures.

Seismic Performance of Composite Shear Walls Filled with Demolished Concrete Lumps and Self-Compacting Concrete after Fire

In order to provide a good solution for the treatment and utilization of construction waste, especially waste concrete and to promote the development of green construction to some extent, in this paper, a new composite shear wall filled with demolished concrete lumps (DCLs) and self-compacting concrete (SCC) was proposed, and its seismic performance after fire was investigated. Based on quasi-static tests of four composite shear walls filled with DCLs and SCC, three after a standard fire and one contrastive specimen without fire, the effects of fire exposure time, fire-retardant coating on the edge constraint steel pipe column, and the width-thickness ratio on seismic performance of composite shear walls after fire were studied. The failure patterns, bearing capacity, hysteretic loops, ductility, skeleton curves, rigidity degradation curves, and energy dissipation of shear walls were analyzed and compared. Test results indicate that the bearing capacity of the shear wall after 60 min of standard fire is slightly lower than the contrastive specimen without fire, but specimens still have good seismic performance. The interlayer displacement angle of the shear wall after a fire still meets the requirement of regulations. The fire-retardant coating on the edge of concealed steel pipe column has a limited effect on the seismic performance of specimens after a fire. The horizontal bearing capacity and energy dissipation capacity of shear walls after a fire can obviously be improved by properly increasing the width-thickness ratio.

Experimental and Analytical Studies of Prefabricated Composite Steel Shear Walls under Low Reversed Cyclic Loads.

Prefabricated composite shear walls (PCSW) consisting of steel plate clapped by single-sided or double-sided prefabricated reinforced concrete (RC) panels have enormous advantages for application as lateral-resisting structures in prefabricated high-rising residential buildings. In this paper, three 1/3-scaled PCSW were manufactured and tested to investigate the seismic performance of PCSW with single-sided or double-sided prefabricated RC panels. The experimental results, including hysteretic and skeleton curves, stiffness and strength degradation, ductility, energy dissipation capability and steel frame effects, were interpreted, compared and summarized. In spite of the RC panels being the same thickness, PCSW with double-sided RC panels had the most outstanding lateral-resisting properties: the highest yield strength and bearing capacity, adequate ductility, plumper and stable hysteresis loop and excellent energy absorption capacity. Finally, a simple predicting equation with a modification coefficient to calculate the effects of boundary steel frame was summarized and proposed to calculate the lateral yield load of the PCSW. All efforts were made to give reliable technical references for the design and construction of the PCSW.

Cyclic behavior of low shear-span ratio dovetailed profiled steel–concrete composite shear walls

Dovetailed profiled steel–concrete composite shear wall (DPSCW) is composed of two skins of dovetailed profiled steel sheeting (DPS) and concrete in between, which is a novel composite member with the potential to serve as a lateral resistant member in low and medium-rise building structures. In addition to functioning as shear connectors to enable the steel–concrete composite action, the dovetailed ribs of DPS embedded in the concrete also make the concrete panel between the DPSs partially slit in the thickness direction, leading to improved seismic performance. This study presents experimental and numerical analyses on the cyclic behaviour of low shear-span ratio DPSCW under combined axial and cyclic lateral loads. Accordingly, two DPSCW specimens with different thickness ratios (ratio of the thickness of the concrete not penetrated by the dovetailed slit to the wall thickness) were tested for failure. All specimens failed in a ductile manner and experienced a flexure-shear mixed mode. The lateral stiffness increased with an increase in the thickness ratio, and the deformability and energy dissipation capacity were reduced. Subsequently, numerical studies were performed to further investigate the failure mechanism of DPSCWs and the effect of the thickness ratio on its lateral behaviour. The dovetailed slits in the concrete panel enable the DPSCW to exhibit an obvious two-stage mechanical response, and a reasonable thickness ratio between 0.19 and 0.5 is recommended. Moreover, simplified models were established to evaluate the lateral resistance of low shear-span ratio DPSCWs. The estimation formulae were found to coincide with the experimental and numerical simulation results.

Seismic performances of the joint between replaceable-coupling beams and composite shear wall

Double-skin composite shear walls (DSCSW) have been widely used in high-rise buildings. A novel joint between the replaceable coupling beam (RCB) and the DSCSW (RCB-to-DSCSW joint) was proposed, and its seismic behavior was investigated. Three specimens with varying lengths of the embedded steel I-beam were subjected to a quasi-static test. The damage mode of the joint includes local buckling of the faceplate, tensile fracture of the faceplate butt weld, and concrete crushing. The tensile fracture of the faceplate weld and the concrete crushing significantly affect the ductility of joints. An increase in the length of the embedded I-beam improves the transfer of external loads to the interior of wall pier. In addition, the specimen with a longer steel I-beam (CJ-3) exhibits higher initial stiffness, strength, and ductility. The cumulative energy consumption of CJ-3 was the highest for the same rotation of loading. A simplified method to calculate the joint bearing capacity according to the components' stress patterns was proposed and validated.

Study on the shear mechanism and resistance of single-side concrete-encased composite plate shear wall

Concrete-encased composite plate shear walls (C-PSW/CEs) are effective structural elements for the lateral load-resisting. With the restraints from concrete panels and headed studs, the shear yielding of infill steel plate can be realized. In service, concrete panel can also provide a significant shear resistance to C-PSWCEs. Especially for the single-side concrete-encased ones, the post-buckling strength for the local buckling of steel plate can be utilized in ductility. However, research on the in-plane behavior of concrete panel or the post-buckling behavior of steel plate in the single-side C-PSW/CE is limited. In this paper, the shear behavior of single-side C-PSW/CE under lateral loading was studied by experiment and finite element analysis. The damage process and shear resistance of C-PSW/CE with different concrete thicknesses were tested. The extended finite element method (XFEM) was employed in the finite element model (FEM) to simulate the cracking of concrete panel. The internal forces in the horizontal and inclined cross sections of steel plate and concrete panel and in the pure shear zones and diagonal tension fields of steel plate were investigated to reveal the shear mechanisms of C-PSW/CE. Based on the parametric analysis results, formulas for the shear stiffness and yield shear force and a mechanics-based model for the shear force-drift ratio response of single-side C-PSW/CE were proposed.