Steel-concrete Composite Shear Walls Research Articles

Macro modeling of steel-concrete composite shear walls

To date, many researchers have developed various types of macro models to simulate the general response of conventional steel plate and reinforced concrete shear walls. Although extensive numerical and experimental studies have been conducted to assess the seismic response of steel-plate concrete composite shear walls, a robust macro-model for simulation of the cyclic response of such systems has not been developed yet.Herein, a fiber-based model is proposed to simulate the nonlinear seismic response of SC walls using PERFORM-3D program. The details of the proposed model, including material properties, element type, and boundary condition, are presented. The proposed model is validated using the available test data of seventeen SC wall specimens with and without boundary elements. Based on the analysis results, this novel approach can capture the global response of SC shear walls including initial stiffness, peak shear strength and its corresponding displacement, stiffness and strength degradation, and pinching behavior accurately. The proposed macro model for SC shear walls can be considered as a reliable tool to extend the engineering application of SC walls in the building industry.

Hysteretic Assessment of Steel-Concrete Composite Shear Walls

This paper focuses on the hysteretic assessment of steel-concrete composite shear walls with reinforced concrete on one side of the steel plate. Finite element software ABAQUS is utilised to conduct this research. An experimental test on a composite shear wall is simulated to do the verification of the modelling. Then, modelling result is compared with the experimental test result which shows an insignificant difference between them and therefore uncovers the accuracy of the modelling. Thereafter, different parameters are considered to investigate their effects on the response of the walls. Thickness of reinforced concrete, steel plate thickness, and number of shear studs are studied as parameters. It is concluded that changing reinforced concrete thickness and number of shear studs do not considerably affect the ultimate load capacity, ductility, and energy dissipation of the walls. However, increasing the steel plate thickness enhances the ultimate load capacity, ductility, and energy dissipation. In addition, out-of-plane displacement of the walls is evaluated.

Fragility curves for steel–concrete composite shear wall building with torsional irregularity

In this study, building model which is trapezoidal in plan with steel–concrete composite shear walls (SCCMSWs) is reduced to 1/4th scale in order to validate modal information and joint responses analytical results with AZALEE shake table under the scope of the SMART program. Incremental dynamic analysis (IDA) is performed on numerical model, and the maximum inter-storey drift is determined as a response parameter for all simulations. Fourteen real ground motion records are used to study the ground motion variability. Further, seismic fragility curves are developed based on IDA results to assess uncertainties in hazard evaluation of structure. Damage probability matrices under various damage states obtained from fragility curves are compared for building as per pre-established damage indicators of SMART 2008 and HAZUS 2003 specifications. It is concluded that, SCCMSWs building structure considered in the study behaves well when subjected to severe earthquakes.

Design of Composite Shear Wall Encased with Vertical Steel Profiles

The concept of steel-concrete composite shear wall is introduced due to the benefits achieved by integrating both the materials. These are structural walls, where steel profiles are encased at the boundary elements. Due to their higher lateral strength and stiffness, they offer a good alternative to improve earthquake resistance over conventional reinforced concrete shear walls in medium and high-rise buildings. Current literature shows that, design procedure of such composite shear walls is not addressed in developing country codes. Hence, a design of steel-concrete composite shear wall is proposed in the present paper on the basis of existing theory and with the help of standard codes. The web portion of shear wall has to be designed as per provisions of Eurocode 8. For the design of composite boundary elements, design norms of composite columns are followed. Also the design of shear stud connectors is adopted according to Eurocode 4.

Buckling Behavior of Steel Plates and Concrete Filled Composite Shear Walls Related Nuclear Power Engineering

Based on the program of nuclear power engineering, the in-plane buckling behavior of Steel plates and concrete filled composite shear wall (SCSW) was investigated. 9 1/5 scaled specimens were conducted under horizontal cyclic load and constant vertical load. The parameters such as the space of studs, the vertical load, the form of connectors, and the thickness of the steel plate were designed to research the affection on the buckling of the steel plate. According to the results of tests, it can be seen that the bulge of the steel plate occurred at about 50mm above the top of the foundation beam. The bulge can be connected as a whole in the specimens with studs only, but not in the specimens with stiffeners. Finite element models were performed to simulate the buckling behavior of the steel plate, and the results were found to be in good agreement with the test results. The buckling stress of the steel plate was calculated by equations based on the measuring data. It was found that they were smaller than that of finite element analysis. The more accurate simulation was needed.

Steel–concrete composite shear walls using precast high performance fiber reinforced concrete panels

SummaryIn this research, seismic performance of composite steel plate shear walls (CSPSWs) using high performance fiber reinforced concrete (HPFRC) panels is experimentally and numerically investigated. Three one‐story one‐bay CSPSW specimens using precast HPFRC panels were designed and fabricated for cyclic quasi‐static experiments. The HPFRC panels of composite shear wall specimens did not have any steel rebars. The main purpose of the study was to understand the effects of rigid and semirigid HPFRC panels on the seismic behavior of the system. Shear capacity, ultimate shear strength, lateral stiffness, energy dissipation, and ductility ratios of the specimens are evaluated.The experimental results demonstrate that specimens were able to resist lateral load up to at least interstory drift of 6%. Using HPFRC panels, CSPSW specimens becomes stiffer in the elastic region, and the yield displacement of the shear wall is decreased; therefore, the ductility ratio of the system is increased. It should be noted that ultimate shear strength, initial elastic stiffness, and energy absorption of specimens with an HPFRC panel on one side or both sides of the infill steel plate were approximately the same. However, using two HPFRC panels is not economical in comparison with CSPSW with an HPFRC panel on one side. Additionally, the second panel increases the seismic mass of the structure.

Energy implications of using steel-timber composite (STC) elements in buildings

Among different structural elements, floor elements account for the largest portion of the mass and thus the embodied energy of the structures. Therefore, a viable approach to reduce the embodied energy of buildings may involve replacing the conventional floor systems with alternative low embodied energy floor systems. This paper investigates the potential reductions in the life cycle energy of the steel structures achievable through the adoption of steel-timber composite (STC) elements as floor and shear wall systems. Evaluating the life cycle energy implications of adopting STC elements is especially important due to the trade-off between their positive and negative effects on embodied energy and operating energy, respectively, when compared to alternative conventional elements with a higher thermal mass including concrete and steel elements. The life-cycle energy of four different structures designed for a building is evaluated by accounting for energy use in material extraction and processing, component manufacturing, transportation, construction, operation and end of life phases. Two steel structures with STC and steel-concrete composite floors and concrete shear walls are considered to evaluate the effects of STC floors on the energy-usage footprint. The third structure is designed with STC floor system and CLT shear walls; and the fourth structure is designed as a concrete structure to provide a basis for comparison between energy footprint of steel structures with STC and reinforced concrete structures. The results indicate that when designing the building with a steel structure, adoption of STC floor and shear wall systems resulted in 107.5% decrease in the embodied energy at the expense of only a slight increase in the operating energy. Furthermore, adopting a steel structure with STC floors was found to result in considerable life cycle energy savings, viz. 895 MJ/m2, when compared with the same building designed with a concrete structure.

Steel plates and concrete filled composite shear walls related nuclear structural engineering: Experimental study for out-of-plane cyclic loading

Based on the program of CAP1400 nuclear structural engineering, the out-of-plane seismic behavior of steel plate and concrete infill composite shear walls (SCW) was investigated. 6 1/5 scaled specimens were conducted which consist of 5 SCW specimens and 1 reinforced concrete (RC) specimen. The specimens were tested under out-of-plane cyclic loading. The effect of the thickness of steel plate, vertical load and the strength grade of concrete on the out-of-plane seismic behavior of SCW were analyzed. The results show that the thickness of steel plate and vertical load have great influence on the ultimate bearing capacity and lateral stiffness, however, the influence of the strength grade of concrete was little within a certain range. SCW is presented to have a better ultimate capacity and lateral stiffness but have worse ductility in failure stage than that of RC. Based on the experiment, the cracking load of concrete infill SCW was analyzed in theory. The modified calculation formula of the cracking load was made, the calculated results showed good agreement with the test results. The formula can be used as the practical design for the design of cracking loads.

Experimental and numerical study on steel-concrete composite shear wall using light-weight concrete

In the present study, the behaviour of concrete stiffened steel plate shear wall (CSPSW) using precast light weight-concrete panels is experimentally and numerically investigated. Three one-bay one-story CSPSW specimens were designed, fabricated, and tested. The steel materials and dimensions of all specimens were the same; however, their precast concrete panels were different. One of the specimens had a precast normal-weight concrete panel on one side of the infill steel plate; on the other hand, another specimen had a light-weight one. The third specimen had two light-weight concrete panels on both sides of the steel plate. The quasi-static cyclic test results indicate that CSPSW with a light-weight concrete panel is a reliable lateral load-resisting system for steel structures. In addition, the shear capacity of specimen with light-weight concrete was approximately similar to specimen with normal-weight one. Therefore, it can be inferred the new system is able to reduce the seismic mass and improve the behaviour of steel structures. In this study, the light-weight concrete panel was 36% lighter than normal-weight panel. Based on the test data, specimens could tolerate high inter-story drift between 5.04% and 6.24% until the shear capacity decline in 80% of the maximum shear load recoded in the test. It should be mentioned that the infill steel plate of CSPSW undergoes entirely inelastic deformation and dissipates significant seismic energy through large lateral displacement.

Damage assessment of steel-plate concrete composite walls by using infrared thermography: a preliminary study

This study aimed to assess the feasibility of using active infrared thermography to detect damage in steel–concrete composite shear walls. An analysis of the transient curves following step heating reveals differences in the transient thermal curves of sound and damaged zones. Contrast and statistical-based techniques are used for discrimination. Theoretical considerations to the implications of detect determination are reviewed, and challenges highlighted to the deployment of this technology for this application. Primary findings hold promise for the future utilization of infrared for detection in this type of structure.

Numerical study on important parameters of composite steel-concrete shear walls

In recent years, steel-concrete composite shear walls have been widely used in enormous high-rise buildings. This paper demonstrates nonlinear numerical studies on composite steel-concrete shear walls affecting cyclic loading. Five types of three-dimensional finite element model is developed using ABAQUS emphasizing constitutive material modeling and element type to represent the real physical behavior of complex shear wall structures. Modeling details of structural components, contact conditions between steel and concrete, associated boundary conditions, and constitutive relationships for the cyclic loading are explained. Load versus displacement curves, peak load, and hysteretic characteristics are verified with experimental data. Present study investigates important parameters such as concrete failure, hysteresis response, out of plan displacement, frame drift, and dissipated energy. The findings revealed that steel frame with concrete, on one side of shear plate, had better dissipation energy function compared with other types. Comparing the results, it was clearly observed that the lateral stiffness of the system isn't affected by changing the distance between connectors and concrete cover thicknesses. Numerical results show that shear steel plate buckling was reduced by increasing concrete thickness, and energy dissipation increased by reducing connectors' distance.

Hysteretic model for steel–concrete composite shear walls subjected to in-plane cyclic loading

Steel–concrete composite (SC) shear walls are being widely used as an alternative to reinforced concrete walls. Investigations on seismic behavior of SC walls have been conducted to develop design specifications for safety-related nuclear facilities. However, there is a lack of hysteretic models that can be used to predict structural performance as the structure approaches collapse. This paper presents (a) the analysis of experimental results of 32 SC wall specimens, and (b) the derivation and calibration of a quadri-linear backbone with negative post-peak stiffness and associated hysteretic rules. Different cross section shapes and loading configurations were used to test the SC wall specimens. Based on the experimental results, equations for stiffnesses and loads are derived from a mechanics based model, and basic hysteretic rules are employed to describe the response of SC walls subjected to in-plane cyclic loading. Calibrations are conducted to suggest the reduction factors for the Young’s moduli of concrete and steel that reflect the plasticity extension and damage accumulation.

Bayesian decision and mixture models for AE monitoring of steel–concrete composite shear walls

This paper presents an approach based on an acoustic emission technique for the health monitoring of steel–concrete (SC) composite shear walls. SC composite walls consist of plain (unreinforced) concrete sandwiched between steel faceplates. Although the use of SC system construction has been studied extensively for nearly 20 years, little-to-no attention has been devoted to the development of structural health monitoring techniques for the inspection of damage of the concrete behind the steel plates. In this work an unsupervised pattern recognition algorithm based on probability theory is proposed to assess the soundness of the concrete infill, and eventually provide a diagnosis of the SC wall’s health. The approach is validated through an experimental study on a large-scale SC shear wall subjected to a displacement controlled reversed cyclic loading.

Experimental and analytical study on seismic behavior of steel-concrete multienergy dissipation composite shear walls

In this paper, a steel-concrete multi-energy dissipation composite shear wall, comprised of steel-reinforced concrete (SRC) columns, steel plate (SP) deep beams, a concrete wall and energy dissipation strips, is proposed. In order to study the multi-energy dissipation behavior and restorability after an earthquake, two stages of low cyclic loading tests were carried out on ten test specimens. In the first stage, test on five specimens with different number of SP deep beams was carried out, and the test lasted until the displacement drift reached 2%. In the second stage, thin SPs were welded to both sides of the five specimens tested in the first stage, and the same test was carried out on the repaired specimens (designated as new specimens). The load-bearing capacity, stiffness, ductility, hysteretic behavior and failure characteristics were analyzed for both stages and the results are discussed herein. Extrapolating from these results, strength calculation models and formulas are proposed herein and simulations using ABAQUS carried out; they show good agreement with the test results. The study demonstrates that SRC columns, SP deep beams, concrete wall and energy dissipation strips cooperate well and play an important role in energy dissipation. In addition, this study shows that the shear wall has good recoverability after an earthquake, and that the welding of thin SP’s to repair a deformed wall is a practicable technique.

Recent progress of seismic research on tall buildings in China Mainland

As a result of rapid economic growth and urbanization in the past two decades, many tall buildings have been constructed in China Mainland, offering researchers and practitioners an excellent opportunity for research and practice in the field of structural engineering. This paper reviews progress by researchers throughout China Mainland on the seismic research of tall buildings, focusing on three major topics that impact the seismic performance of tall buildings. These are: (1) new types of steel-concrete composite structural members such as steel-concrete composite shear walls and columns, (2) earthquake resilient shear wall structures such as shear walls with replaceable structural components, self-centering shear walls and rocking walls, and (3) performance-based seismic design, including seismic performance index, performance level and design method. The paper concludes by presenting future research needs and directions in this field.

MODELING OF NONLINEAR CYCLIC LOAD BEHAVIOR OF I-SHAPED COMPOSITE STEEL-CONCRETE SHEAR WALLS OF NUCLEAR POWER PLANTS

In recent years steel-concrete composite shear walls have been widely used in enormous high-rise buildings. Due to high strength and ductility, enhanced stiffness, stable cycle characteristics and large energy absorption, such walls can be adopted in the auxiliary building; surrounding the reactor containment structure of nuclear power plants to resist lateral forces induced by heavy winds and severe earthquakes. This paper demonstrates a set of nonlinear numerical studies on I-shaped composite steel-concrete shear walls of the nuclear power plants subjected to reverse cyclic loading. A three-dimensional finite element model is developed using ABAQUS by emphasizing on constitutive material modeling and element type to represent the real physical behavior of complex shear wall structures. The analysis escalates with parametric variation in steel thickness sandwiching the stipulated amount of concrete panels. Modeling details of structural components, contact conditions between steel and concrete, associated boundary conditions and constitutive relationships for the cyclic loading are explained. Later, the load versus displacement curves, peak load and ultimate strength values, hysteretic characteristics and deflection profiles are verified with experimental data. The convergence of the numerical outcomes has been discussed to conclude the remarks.

Nonlinear Finite-Element Analysis of Double-Skin Steel-Concrete Composite Shear Wall Structures

Shear wall structures have been widely used in high-rise buildings due to their good lateral resistant behavior. As a new type of shear wall structure, the double-skin steel-concrete composite shear wall has high loading capacity, superior ductility and good crack resistant behavior. The mechanical properties of the composite walls need to be further studied. Based on the general FE package MSC.Marc(2005r2), an elaborate finite element analysis of the double-skin steel-concrete composite shear wall is conducted to simulate the whole-process behavior of the shear wall. The load-displacement relationship is obtained, and the slippage characteristic of the steel plate-concrete interface is also intensively investigated through enforcing the spring elements at the interface. Finally, the influence of the axial compression ratio and the steel plate thickness is presented by a parametric analysis. The conclusions drawn from the analysis are that the maximum slippage of the shear wall occurs at the tension side of the wall bottom where the concrete cracks and the axial force-moment curve has a parabolic property. The relevant conclusions are useful for the routine design practice of tall buildings.

Tests on Seismic Behavior of Steel-Concrete Composite Fabricated Shear Wall Specimens

Quasi-static tests of three specimens of steel-concrete composite fabricated shear wall were performed to investigate its seismic behavior. The test results indicate that horizontal cracks run through the interface between the wall and the base beam, diagonal cracks appear on the whole prefabricated concrete shear wall. The specimens fail in the mode of bending-shear, the hysteretic curves according to the test were full, it means that they have better seismic bearing capacity.

Cyclic loading test of T‐shaped mid‐rise shear wall

SUMMARYShear wall systems are the most commonly used lateral load resisting systems in high‐rise buildings. Six 1:2 scale mid‐rise T‐shaped reinforced concrete shear wall specimens with aspect ratio of 1.75, 2.15 and 2.80 were respectively tested under reversed cyclic loading. The seismic behavior and displacement ductility were investigated. The effects of aspect ratio, axial load level and transverse steel ratio on the seismic behavior and displacement ductility were also analyzed. Test results were discussed and compared with T‐shaped steel–concrete composite shear wall. Results mainly showed that the T‐shaped shear wall specimens mainly presented bending–shear failure mode and were all destroyed because of the concrete crushing at the web (negative direction) and the longitudinal reinforcement of the web reaching the limited deformation (positive direction), showing that the web was the weakest part of T‐shape shear wall. The ductility of the specimens was decreased, and the ultimate load‐bearing capacity was increased by increasing the axial load. To specimens with smaller aspect ratio and higher axial load ratio, the special transverse steel ratio of the web should be increased to improve the crushing strain of the confined concrete of the web in order to satisfy the ductility of the walls. The seismic performance was obviously improved in the T‐shaped steel–concrete shear wall compared with that of the T‐shaped reinforced concrete shear wall. Copyright © 2011 John Wiley & Sons, Ltd.