Design of Noncontact Lap Splice Connections for C-PSW/CF (SpeedCore)

Pullout behavior of lap splice connections between double-steel-plate composite walls and RC raft foundation in nuclear engineering

SummaryThe nonlinear pushover analyses of 24 composite steel plate shear walls (CSPSWs), 24 corresponding steel plate shear walls (SPSWs), and 24 corresponding frames are conducted. CSPSWs have different aspect ratios and infill steel plate thicknesses. The study aims to understand the wall–frame and steel–concrete interactions. The infill steel plate thickness and aspect ratio of CSPSW are the main parameters of the study.In CSPSWs, the percentage of absorbed shear forces by the infill composite wall is always greater than the infill plate of its corresponding SPSW. The percentage of shear in the composite wall is constant at the initial stage of loading up to a drift of 0.15–0.2%. By increasing the drift, the shear yielding of steel plate leads to a reduction of the shear force absorption. The reduction continues until the bulk of shear stiffness of CSPSW is provided by the frame.At the beginning of lateral loading, steel–concrete interactions increase until shear yield of steel plate. Following this stage, a sudden decrease takes place in shear force absorption of reinforced concrete (RC) panel. The reason is that, at the lower drifts, the steel plate has a tendency for elastic buckling, which is prevented by the RC panel. Finally, the shear force absorption remains approximately constant in the RC panel.

Based on the research of composite walls at home and abroad, a construction method of continuous opening of the insulation layer in the specimen is proposed. In the edge component of the composite wall, the insulation layer should be thinned appropriately, the concrete on both sides should be thickened correspondingly, and U‐shaped reinforcement should be used instead of stirrup. To study its axial compression test performance, five 1/2 scale composite shear wall specimens are tested under axial compression, including three composite wall specimens and two solid wall contrast specimens. The failure mode, load‐bearing performance, deformation performance, and the collaborative work performance of wall are analyzed. The results show that the failure characteristics of the composite shear wall are similar to those of the solid wall, with splitting cracks at the corners and inverted triangular conical splitting at the top of the wall along the wall height direction, with no obvious bulging in the middle of the wall. The tie action of the ribs makes the concrete walls on both sides of the composite shear wall have good integrity and cooperative performance; the installation of the thermal insulation layer increases the overall thickness of the wall, improves the stability of the composite wall, and makes the composite wall axially compressed. The bearing capacity is not significantly reduced compared to the solid walls. Finally, according to the test results, the calculation formula of axial compression bearing capacity of composite shear wall is given, which provides the basis for the formulation of the code and engineering application.

Parametric study on lateral behaviour of composite shear walls with high-strength manufactured sand concrete

Shear walls are one of the important structural elements for bearing loads imposed on buildings due to winds and earthquakes. Composite shear walls with high lateral resistance, and high energy dissipation capacity are considered as a lateral load system in such buildings. In this paper, a composite shear wall consisting of steel faceplates, infill concrete and tie bars which tied steel faceplates together, and concrete filled steel tubular (CFST) as boundary columns, was modeled numerically. Test results were compared with the existing experimental results in order to validate the proposed numerical model. Then, the effects of some parameters on the behavior of the composite shear wall were studied; so, the diameter and spacing of tie bars, thickness and compressive strength of infill concrete, thickness of steel faceplates, and the effect of strengthening the bottom region of the wall were considered. The seismic behavior of the modeled composite shear wall was evaluated in terms of stiffness, ductility, lateral strength, and energy dissipation capacity. The results of the study showed that the diameter of tie bars had a trivial effect on the performance of the composite shear wall, but increasing the tie bars spacing decreased ductility. Studying the effect of infill concrete thickness, concrete compressive strength, and thickness of steel faceplates also showed that the main role of infill concrete was to prevent buckling of steel faceplates. Also, by strengthening the bottom region of the wall, as long as the strengthened part did not provide a support performance for the upper part, the behavior of the composite shear wall was improved; otherwise, ductility of the wall could be reduced severely.

Performance of reinforced concrete composite wall systems under projectile impact

Precast buildings have attarcted worldwide attention because of their significant role in the realization of sustainable urbanization. In this study, a precast buckling-restrained composite shear wall (PBRSW) system is developed, which is assemblied by multiple composite shear wall modules on site. The PBRSW system with three assembly arrangements of the composite shear wall modules, vertical, horizontal and cross arrangements, are designed and explored comparatively to mitigate buckling phenomena and obtain beneficial mechanical behaviours with experiment and simulation methods. To bring insight the seismic performance of the developed system, traditional buckling-restrained shear wall (BRSW) system and steel plate shear wall (SPSW) system are further investigated. The results show that the PBRSW system achieves plumper hysteresis behaviors, higher force-bearing and energy-dissipation capacities, and better ductility performance than that of the other two systems. Buckling phenomena of the PBRSW system are restrined effectively, and its maximum out-of-plane displacement is only 1/18 and 1/15 of the SPSW and BRSW systems on average respectively. The PBRSW system with vertical arrangement of the composite shear wall modules shows the best mechanical behavior with the highest bearing capacity and energy dissipation among the three assembly arrangements. Experimental data coincides well with those from finite element model (FEM) analysis and therefore validates FEM.

Steel-plate composite (SC) walls: Out-of-plane flexural behavior, database, and design

The composite shear wall structure is an industrialized and promising product in civil engineering. Its application in the industry is limted and not satisfying due to the tremendous difficulty in manufacturing the lattice reinforced shear walls and large amount of used steel. This paper proposes a new-type composite shear wall with easy fabrication process and decreased weight. The mechanical properties of the composite walls were studied by performing quasi-static experiments on four proposed composite shear walls and one conventional concrete shear wall. The influence of shear-span ratio, axial load ratio and interface connection on seismic behaviors of the composite structure were included by analyzing the bearing capacity, hysteresis and skeleton curves, stiffness degeneration, displacement ductility and energy dissipation capacity. Results show that the new-type composite shear wall shows good seismic performance and similar mechanical properties with the conventional wall; Shear studs installed at the interface between the precast fibergalss reinforced cement plate and cast-in-place concrete can improve the bonding performance, initial stiffness and energy dissipation capacity; Increasing the axial load ratio and reducing shear-span ratio can improve the bearing capacity of the shear wall. A formula was developed to calculate the bearing capacity of the normal section of such composite shear walls, which shows good agreement with the test results. This study may provide reference for design and engineering applications of the composite shear walls. Keywords: Composite shear wall, Seismic performance, Quasi-static test, Interface bonding, Shear studs

The seismic performance of recycled aggregate concrete (RAC) composite shear walls with different expandable polystyrene (EPS) configurations was investigated. Six concrete shear walls were designed and tested under cyclic loading to evaluate the effect of fine RAC in designing earthquake-resistant structures. Three of the six specimens were used to construct mid-rise walls with a shear-span ratio of 1.5, and the other three specimens were used to construct low-rise walls with a shear-span ratio of 0.8. The mid-rise and low-rise shear walls consisted of an ordinary recycled concrete shear wall, a composite wall with fine aggregate concrete (FAC) protective layer (EPS modules as the external insulation layer), and a composite wall with sandwiched EPS modules as the insulation layer. Several parameters obtained from the experimental results were compared and analyzed, including the load-bearing capacity, stiffness, ductility, energy dissipation, and failure characteristics of the specimens. The calculation formula of load-bearing capacity was obtained by considering the effect of FAC on composite shear walls as the protective layer. The damage process of the specimen was simulated using the ABAQUS Software, and the results agreed quite well with those obtained from the experiments. The results show that the seismic resistance behavior of the EPS module composite for shear walls performed better than ordinary recycled concrete for shear walls. Shear walls with sandwiched EPS modules had a better seismic performance than those with EPS modules lying outside. Although the FAC protective layer slightly improved the seismic performance of the structure, it undoubtedly slowed down the speed of crack formation and the stiffness degradation of the walls.

Experimental and numerical study on seismic behavior of prestressed concrete composite shear wall

Deformation capacity of concrete-filled steel plate composite shear walls

The composite shear wall is the core component of the thermal insulation integrated structure, which is a load‐bearing shear wall with good thermal insulation, sound insulation, and seismic resistance. To improve the applicable height of the composite shear wall structure, a cohesive sandwich heat‐insulation composite shear wall with door frame inclined tendon and diamond‐shaped inclined tendon is proposed, and the quasistatic force of four 1/2‐scale shear wall test specimens is carried out. Different specimens are analyzed, including failure modes, hysteresis curves, skeleton curves, stiffness degradation, ductility performance, and energy dissipation capacity. The following conclusions are drawn: the failure modes of the specimens are bending and shear failure; the ultimate strength and deformation performance of the composite wall close to the solid wall; the composite wall with the door frame inclined tendon can effectively delay the wall cracking and improve the bearing capacity and energy consumption capacity of the composite wall; the configuration of the diamond‐shaped inclined tendon improves the ductility and energy dissipation capacity of the composite wall.

Finite element modeling of double skin profiled composite shear wall system under in-plane loadings

This paper presents the low-cyclic reversed tests and numerical simulation on partially prefabricated laminated composite reinforced concrete (RC) walls. The specimens include 4 typical composite walls without openings, 4 with openings, and 1 common cast-in-place RC wall. The structural behaviours including failure pattern, lateral load-top drift relationship and the in-plane horizontal load carrying capacity of the composite RC walls were compared with the common cast-in-place RC walls through the experiments. Then the finite element software ABAQUS was employed to simulate the experiment scenarios. The simulation results are consistent with the experimental results. After that, further simulation was conducted on the composite walls and the common cast-in-place wall under different axial forces. Experimental and numerical study indicates that there is no obvious difference in horizontal load carrying capacity and failure pattern between the composite walls and the common cast-in-place walls under the test axial ratios, but the composite walls are more vulnerable to failure under high axial force compared with the cast-in-place wall. Though they have many advantages in rapid construction, especially in reconstruction of the earthquake-hit areas, the laminated composite walls are not suggested to apply under high axial ratio conditions.