Concrete Composite Wall Research Articles

Mechanics-Based model for elastic Bending, Axial, thermal Deformations, and asymmetry of concrete composite sandwich wall panels

Engineers must design load-bearing panels to handle gravity loads, out-of-plane loads and deformations due to thermal bowing. Outside of finite element analysis (FEA), there is currently no codified or well-accepted design or analysis method within the literature that can perform these calculations within the same framework. This paper describes the theory, development, and validation of a new mechanics-based model (MBM) for partially composite concrete sandwich wall panels in the elastic range. Most concrete sandwich wall panels in the United States are designed exclusively in the elastic range. The MBM is suitable for incorporation into a spreadsheet (provided) or computer program and can provide analysis information suitable for practical design. The model is validated based on available experiments with an average measured-to-predicted ratio of 0.98 for deflections in out-of-plane loading and 1.08 for thermal bowing estimation. A parametric study and comparison to FEA is performed to illustrate the robustness of the MBM to handle different situations including openings, eccentric dead loads and asymmetric panels.

Investigation on the resistance of steel-plate concrete walls under high-velocity impact

In this study, an influence of the front steel plate of the steel-plate concrete (SC) composite walls on the impact resistance performance is analytically derived, and verified by comparison with numerical analyses and experiment results. SC composite wall is remarkably superior in resistance against impacts compared to normal concrete because steel plates control and prevent fragmentation caused by the fracture of concrete material. An analytical criterion for estimating resistance capacity against impact loads is proposed by adding the effect of a front steel plate into the existing impact resistance equation of SC composite walls, and the criterion more accurately predicts the failure modes of SC composite walls in the impact tests. Finite element (FE) models are constructed to predict the impact response of SC composite walls numerically and verified with experiment results. The critical velocity is numerically derived using FE models by performing a large number of iterative simulations, and the proposed criterion including the effect of front steel plate is more accurate for estimating critical velocity than the formula that ignores the front steel plate. The proposed analytical and numerical procedures will be useful for assessing the critical velocities and failure modes of SC composite walls with better accuracy.

Seismic behavior of double steel concrete composite walls

SummaryAn innovative double steel concrete (DSC) composite walls were developed to enhance constructability and lateral load resistance of buildings. In order to research the seismic behavior of DSC composite walls, experimental study was carried out. The high‐strength concrete and high axial load were considered. The failure mode, hysteresis behavior, lateral load‐carrying capacity, deformation, and energy dissipation of the composite walls under different testing parameters were observed. All specimens failed in a flexure behavior, with steel plate buckling and concrete compressive crushing in the bottom of composite walls. The pinching behavior was not significant for hysteresis loops of composite walls. Moreover, the lateral load‐carrying capacity and ductility coefficients increased significantly with spacing of constraining bolts and stiffeners decreased. In addition, the calculation method of the lateral load‐carrying capacity of DSC composite walls was proposed, with the consideration of force equilibrium and moment equilibrium. The finite element (FE) method was performed to analyze the failure process of the specimens with the cyclic load. The concrete damage plastic model was selected to simulate the damage progress of concrete. Validation of the FE models against the experimental results showed good agreement. The effect of different parameters was analyzed with FE models.

Quasistatic Cyclic Tests and Finite Element Analysis of Low‐Aspect Ratio Double Steel Concrete Composite Walls

An innovative double steel concrete (DSC) composite wall was developed to enhance constructability and lateral load resistance of buildings. Three low‐aspect ratio DSC composite walls were constructed and tested to study the shear behavior. Under different testing parameters, the failure modes, hysteresis behavior, lateral load resisting capacity, deformation, and energy dissipation of the composite walls were observed. The results showed that all specimens failed in shear behavior with steel plate buckling and concrete compressive crushing. The pinching behavior was obvious for hysteresis loops of composite walls. Moreover, the lateral load resisting capacity and deformation were significantly affected with axial compression ratio and steel ratio. Beyond that, the ductility coefficients of specimens reached 3.30. The finite element (FE) method was performed to analyze the failure process of the specimens with cyclic analysis. The concrete damage plastic model (CPDM) was selected to simulate the damage progress of concrete. Validation of the FE models against the experimental results showed good agreement.

Seismic Behaviour of Cast‐In‐Situ Phosphogypsum‐Reinforced Concrete Grid Frame Composite Walls

This paper mainly studies the effect of cast‐in‐situ phosphogypsum on seismic behaviour of reinforced concrete grid frame. The mechanical behaviour of three reinforced concrete grid frames and four cast‐in‐situ phosphogypsum‐reinforced concrete grid frame composite walls under low cycle alternating load was designed and tested. The test results show that the reinforced concrete grid frame has less bearing capacity and poor energy consumption. The addition of cast‐in‐situ phosphogypsum can effectively improve the seismic behaviour of the reinforced concrete grid frame. Compared with the reinforced concrete grid frame, the bearing capacity of the cast‐in‐situ phosphogypsum‐reinforced concrete grid frame composite wall is increased by 2‐3 times, the displacement ductility coefficient is increased by 0.95∼1.2 times, and the relative accumulative energy consumption is increased by 86%∼216%. This shows that the composite wall has better bearing capacity, ductility, and energy dissipation capacity.

Seismic Behavior of Steel Reinforced High-Strength Concrete Composite Walls

ABSTRACT Eight steel reinforced high-strength concrete composite walls were manufactured and quasi-statically tested. The testing objective was to investigate the seismic behavior of composite walls, including the failure mode, hysteresis curve, deformation, energy dissipation, and stiffness degradation. The results showed that all specimens failed during the flexural mode. The lateral load-resisting capability and deformation capability significantly increased with increasing steel ratio and stirrup characteristic value. In addition, formulations were proposed to evaluate the lateral load-resisting capability of steel reinforced concrete (SRC) composite walls, and the evaluated results exhibited good agreement with the test results.

Seismic Performance of Endplate Connections between Steel Reinforced Concrete Walls and Steel Beams

In recent years, a coupled composite shear wall system consisting of steel reinforced concrete (RC) composite wall piers and steel coupling beams has been widely used for lateral force resistance in super high-rise buildings in medium to high seismic zones in China. Research on the seismic behaviour of the coupled composite walls, however, has rarely been conducted. This paper presents the main experimental results of four steel beam RC composite wall subassembly specimens with endplate connections in terms of failure pattern, strength, ductility and energy dissipation. Mathematical macroscopic models are established based on the proposed mechanical and numerical techniques. The simulated load versus displacement skeleton curves and hysteretic loops are obtained and compared to experimental results. The simulation results are found to have good agreement with the experimental data, indicating the applicability of the proposed nonlinear modelling techniques.

Seismic Behavior of Bolted Endplate Connection Between Steel Reinforced Concrete (SRC) Wall and SRC Beam for Use in High-Rise Buildings

To improve the constructability of the steel and concrete composite coupled wall system while maintaining good seismic performance in terms of strength, stiffness and energy dissipation capacity, the bolted endplate connection between steel reinforced concrete (SRC) wall and SRC beam has been proposed and studied. The endplate is shop welded to the end of steel beam and then fastened to the flange of steel column at boundary element of wall pier through high-strength bolts before the fabrication of reinforcement cage and concrete pouring for the composite beams. Five SRC beam-SRC wall subassembly specimens were designed, constructed and tested subjected to cyclic displacement reversals at SRC beam end. The test parameters included the amount of steel plate embedded in SRC beams and the influence of slab. The responses of the specimens in terms of load–displacement hysteretic responses, cracking patterns, ductility, strength and stiffness degradation characteristics were discussed. The test results show that through rational design the bolted endplate connection can satisfactorily ensure the load transfer mechanism between SRC beam and SRC wall such that the SRC beam can fully develop its strength, ductility, post-yield strength and stiffness retention capacities. The strength, post-yield deformation and energy dissipation capacity of SRC coupling beams can be effectively enhanced by increasing the steel plate ratio. The existence of slab can enhance the overall seismic performance of SRC beam. Nonlinear finite element modeling approach was developed and verified by comparison with the test results, showing good agreement in terms of the skeleton and hysteresis curves.

Numerical modelling of steel-plate concrete composite shear walls

This paper presents a numerical study of steel-plate concrete (SC) composite walls using the general-purpose finite element (FE) program ABAQUS. Predictions are compared to data from reversed cyclic, inelastic tests of four large-scale SC wall piers with an aspect ratio of 1.0. Each wall comprises two steel faceplates, infill concrete, steel studs and tie rods as connectors, and a steel baseplate that connects it to the reinforced concrete (RC) foundation. Key design variables are studied, including reinforcement ratio, connector type, and faceplate slenderness ratio. The predicted responses including global force-displacement relationships, damage to infill concrete and steel faceplates, shearing force contributions, and connector behavior, are in good agreement with the measured data. The steel faceplates are found to contribute between 20% and 70% of the total shearing resistance of the SC wall piers evaluated here, depending on the reinforcement ratio, faceplate slenderness ratio, story drift, and level of damage. Tie-rods are preferred to shear studs in the first few rows of connectors above the baseplate, where significant out-of-plane buckling of the steel faceplates and damage of the infill concrete are expected.

Use of inclined studs in steel-plate–concrete composite walls with shear and axial loading

An analytical study is conducted to examine the effect of shape and spacing of inclined shear studs in steel-plate–concrete composite walls subject to shear and axial loading. Finite-element analyses of steel-plate–concrete shear walls were carried out considering different shapes and spacing of the studs. It was found that the shape of the studs has little effect on shear performance compared to spacing. When the studs are widely spaced, composite action is poor, the steel plate yields under a relatively minor load and the concrete is damaged. If spaced too closely, the studs also damage the concrete due to excessive restraint. It was also confirmed that inclined studs are more effective than normal studs for controlling buckling.

Research on the Vertical Bearing Capacity of Light Steel-foam Concrete Composite Wall Frame Column

Using the finite element method to analysis the bearing capacity of light steel-foam concrete composite wall frame column under vertical load. Through the analysis of the bearing capacity of the wall frame columns filled with different grades of foamed concrete under the vertical load, the results of the effect of filled foamed concrete on the bearing capacity of light steel composite wall are obtained. Results show: 1) for the light steel structure with no foamed concrete, the spacing of the wall frame column is increased from 400mm to 600mm, and the axial load bearing capacity is reduced. 2) for the steel foam concrete filled with 12MPa foam concrete structure, the spacing of the wall frame column is increased from 400mm to 600mm, the axial bearing capacity decreases slightly. 3) when the strength of foam concrete is reduced to 8MPa, or increased to 24MPa, the spacing of the wall frame column increases from 400mm to 600mm, the axial bearing capacity decreases first and then increases.

Seismic behavior of composite walls with encased steel truss

This paper studies the seismic behavior of reinforced concrete (RC) walls with encased cold-formed and thin-walled (CFTW) steel truss, which can be used as an alternative to the conventional RC walls or steel reinforced concrete (SRC) composite walls for high-rise buildings in high seismic regions. Seven one-fourth scaled RC wall specimens with encased CFTW steel truss were designed, manufactured and tested to failure under reversed cyclic lateral load and constant axial load. The test parameters were the axial load ratio, configuration and volumetric steel ratio of encased web brace. The behaviors of the test specimens, including damage formation, failure mode, hysteretic curves, stiffness degradation, ductility and energy dissipation, were examined. Test results indicate that the encased web braces can effectively improve the ductility and energy dissipation capacity of RC walls. The steel angles are more suitable to be used as the web brace than the latticed batten plates in enhancing the ductility and energy dissipation. Higher axial load ratio is beneficial to lateral load capacity, but can result in reduced ductility and energy dissipation capacity. A volumetric ratio about 0.25% of encased web brace is believed cost-effective in ensuring satisfactory seismic performance of RC walls. The axial load ratio should not exceed the maximum level, about 0.20 for the nominal value or about 0.50 for the design value. Numerical analyses were performed to predict the backbone curves of the specimens and calculation formula from the Chinese Code for Design of Composite Structures was used to predict the maximum lateral load capacity. The comparison shows good agreement between the test and predicted results.

Cyclic shear behavior of composite walls with encased steel braces

The composite wall with encased steel braces (ESB wall) is a novel type of steel–concrete composite wall that consists of a steel braced frame embedded in reinforced concrete. This arrangement is supposed to enhance the seismic performance of the wall, as the steel columns encased in the boundary elements can increase the flexural strength of the wall and the steel braces encased in the web can increase the shear strength. This paper examines the cyclic shear behavior of squat ESB walls by conducting quasi-static tests. Two wall specimens with an encased single-diagonal brace, one of which had an I-shaped brace and the other a steel plate brace, were tested. Both specimens had a shear-to-span ratio of 1.06, and they were subjected to a moderate axial force ratio of 0.18. A flanged wall section was intentionally used to ensure that the wall’s flexural strength exceeded the shear strength, resulting in a shear failure mode. The two specimens failed in a similar manner, characterized by crisscrossed-diagonal cracking and crushing of the concrete in the web panel. Hysteretic responses of the two specimens were nearly identical, and both types of steel braces buckled after they yielded. This indicates the potential use of steel plate braces instead of I-shaped braces in ESB walls, as the former allows improved efficiency and quality of construction. A simple method was presented to calculate the cracked shear stiffness of ESB walls, and this method could reasonably estimate the cracked shear stiffness of the specimens. In addition, the JGJ 138-2012 formulas for assessing the shear strength of ESB walls were calibrated through the analysis of data collected in past tests and in the present experimental program. The design formulas, based on the superposition method, are found to provide reasonable and conservative predictions of the shear strength capacity of ESB walls.

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.

Seismic behavior of high strength concrete composite walls with embedded steel truss

Experimental investigation was conducted on three 1:3 scaled high strength concrete composite wall (HSCCW) specimens with embedded steel truss with a medium aspect ratio (1.0–3.0) under cyclic load reversals and constant axial load, to examine the influences of steel usages of embedded truss chord and web brace on the overall seismic behavior of the specimens. The hysteretic characteristics, cracking pattern, failure modes and energy dissipation capacities of the specimens were discussed. Then parametric analysis was carried out on 27 numerical models based on verified finite element modeling techniques to thoroughly evaluate the influences of axial load ratio, steel ratio of embedded truss chord and volumetric ratio of embedded truss web brace on the overall seismic performance of HSCCW with embedded steel truss. Research results indicate that increasing the steel ratio of embedded truss chord can effectively improve the initial stiffness and lateral load carrying capacity. Although the volumetric ratio of embedded truss web brace has little influence on lateral strength, it is beneficial to the energy dissipation capacity of composite walls. Within the maximum allowable limit, higher axial load ratio can result in increased lateral load capacity and stiffness.

Experimental seismic behavior of innovative composite shear walls

In this paper, an innovative structural wall, named bundled lipped channel–concrete (BLC–C) composite wall, is proposed. The proposed wall consists of bundled lipped channels seam-welded together and in-filled concrete. Seven full-scaled specimens were tested under axial load subjected to cyclic lateral load. The variables studied in the experiments include the configuration of the walls, the axial load ratio, the presence of shear studs, and the loading history. The specimens exhibited ductility and experienced stable hysteresis behavior. The specimens failed in the sequence of local buckling of the steel sheet, and the propagation of the fractures at the boundary of the wall. The seismic behavior of the specimens was evaluated in terms of strength, stiffness, deformation, ductility, and energy dissipation capacity. The results indicate that the level of axial force ratio and the configuration detail significantly affect the entire hysteresis performance, while the presence of shear studs delays the occurrence of fracture and failure.

Seismic behavior of a containment internal structure consisting of composite SC walls

This paper presents the lateral load behavior of a 1/10th scale model of a pressurized water reactor (PWR) containment internal structure (CIS). The entire CIS including the steam generator compartments, pressurizer, reactor cavity walls, etc. are made of steel–concrete composite (SC) walls. The lateral load behavior of the 1/10th scale model of the CIS was investigated experimentally by researchers in Japan, and presented at the 10th Structural Mechanics in Reactor Technology (SMiRT) Conference in 1989. Recent advancements in finite element modeling techniques, and computer-based analysis approaches have enabled the numerical simulation of the lateral load behavior of the 1/10th scale CIS tested earlier. This paper presents: (i) the development of 3D nonlinear inelastic finite element (NIFE) models of the 1/10th scale CIS, (ii) the comparison and benchmarking of numerical results with experimental results and observations, and (iii) the overall lateral load-deformation behavior of the CIS including the formation of ductile energy dissipating mechanisms in the SC walls. The results and findings are used to provide recommendations for modeling CIS structures consisting of SC walls while conducting nonlinear analysis to evaluate their seismic performance for design and beyond design basis events.

Seismic behavior of double steel plate–HSC composite walls

Double steel plate–high strength concrete composite wall (DSP–HSCW) is a new lateral force-resisting system, with concrete filled steel tube (CFST) column as boundary element. The wall combines the favorable strength and stiffness characteristics of high performance concrete (HSC) with the ductility of the steel plate. A series of tests were conducted to investigate the response of the DSP–HSCW system under cyclic loading. The parameters investigated in the tests included the axial-load ratio (applied axial load to bearing capacity) and the ratio of the tie bar spacing to steel plate thickness. The test results showed that unlike conventional HSC walls, the wall specimens exhibited high strength as well as excellent deformation capacity. The wall specimens with large height-to-width ratio showed flexure-dominated behavior through cantilever action. The primary failure mode is axial–flexural mode, which is characterized by local buckling of the steel plates followed by compressive crushing of concrete at the wall bottom. The axial-load ratio has a significant effect on the strength and deformation capacity of DSP–HSCW system. To enhance deformation capacity to meet a specific demand, the ratio of the tie bar spacing to steel plate thickness should be reduced. The paper adds to existing research database on the performance of DSP–HSCW under lateral demands and provide valuable insight on the performance of such system.

Seismic performance of steel–concrete composite structural walls with internal bracings

This paper presents experimental and analytical investigations of steel–concrete composite structural walls with internal bracings. In the experimental study, four full-scale wall specimens were tested under cyclic load reversals. The performance of the wall specimens in terms of load–deformation response and cracking patterns is described. However, due to the inherent complexity of shear walls and unique features of the embedded diagonal bracing, the experimental investigation was not sufficient to fully explain the influence of several parameters. Therefore, an analytical investigation based on the FE models using DIANA is presented. Validation of the FE models against the experimental results has shown a good agreement. Critical parameters influencing the shear wall's behavior such as shear span ratio, axial load, the size and thickness of shaped steel are varied, and their effects on the walls' seismic behavior are discussed.

Inplane Shear Behaviour of Steel – Foam Concrete Composite Wall Panels

Inplane Shear Behaviour of Steel – Foam Concrete Composite Wall Panels