2022 Vol. 37, No. 8

Review
Review on the Axial Compression Performance of Double-Steel-Plate Composite Shear Wall
Yegang You, Jian Li, Teng Wang, Lipeng Huang, Gang Gao
2022, 37(8): 1-8. doi: 10.13206/j.gjgS21122004
Abstract:
Double-steel-plate composite shear wall, consisting of bilateral steel plates, in-filled concrete, and mechanical connectors between steel plates, has many advantages such as light weight, high compression, high ductility, thin wall, good seismic performance, and higher prefabrication rate. With the continuous improvement of building height and functional requirements, it has been widely used and developed.
This paper summarized the research status of the axial compression performance of double-steel-plate composite shear wall and introduced several prevailing mechanical connector types including shear studs, binding bolts, hybrid connections, new mechanical connections, and so on. Then focusing on the axial compression performance, which is the basis of complex mechanical properties such as earthquake resistance and shear resistance, the change laws of axial compression bearing capacity and failure modes under the influences of different mechanical connector types and parameter variables were analyzed and summarized. The initial stiffness, limiting value of distance-to-thickness ratio(the ratio of connector distance to steel plate thickness), and calculation theory of axial compression capacity for double-steel-plate composite shear wall were also analyzed. Finally, this paper pointed out some problems in the current research from five aspects:theoretical studies, mechanical connectors, connecting joints, construction applications, and durability, and gave a prospect on the future development trend of double-steel-plate composite shear walls in high-rise buildings.
Based on the analysis of current research status, it is concluded that:the buckling of steel plate is the key factor to determine the axial compressive bearing capacity of double-steel-plate composite shear wall, and according to the value of distance-to-thickness ratio, the failure modes of double-steel-plate composite shear wall are divided into two cases:the steel plate buckles before yielding, and the steel plate buckles after yielding. In engineering practice, it is required to avoid the failure mode in which the steel plate buckles before yielding by changing the distance-to-thickness ratio. Arranging a certain amount of mechanical connectors along the height and width of the wall specimen can make full use of the material properties of concrete, prevent the brittle failure caused by the steel plate buckling, improve the axial compression bearing capacity and ductility of the specimen, and ensure that the wall stiffness remains almost constant until failure.
Research
Study on Flexural Capacity of Profiled Steel Sheet-Polyurethane Sandwich Slabs
Teng Wang, Huikang Feng, Wentao Qiao, Jizhi Su, Lihuan Wang
2022, 37(8): 9-16. doi: 10.13206/j.gjgS22031502
Abstract:
The metal-faced sandwich panel has been used in the envelope structure for its advantages of thermal insulation, noise reduction, light weight and high assembly efficiency. Based on the structure of metal sandwich panels, a new type of profiled steel sheet and polyurethane sandwich slab(PSSPSS) was proposed. In order to study the flexural capacity of PSSPSS, two-point symmetric load static test was carried out on the slab. Based on the experimental results, the finite element analysis model of PSSPSS was proposed and verified, and the parameters of the channel steel slab thickness, profiled steel sheet thickness and polyurethane density were analyzed.
The results show that:the failure mode of sandwich slab is mainly shown as too large deflection, the maximun deflection is one forty-second of the span of the slab, and the channel steel at the middle section of the span appears distortion buckling. After the sandwich slab is bent and deformed, the channel steel reaches the yield state first, while the material properties of the compression steel plate are not fully developed. Compared with traditional metal sandwich panels, the bearing capacity and stiffness of PSSPSS are improved by 203% and 203% respectively.The thickness of slab and profiled steel sheet has significant influence on the bearing capacity and stiffness of sandwich slab, while the thickness of slab has more obvious influence on stiffness than the thickness of profiled steel sheet. the thickness of slab increases from 120 mm to 160 mm, the bearing capacity of sandwich slab increases by 87% in normal use, 63% in ultimate bearing capacity and 88% in stiffness. the thickness of steel sheet increases from 1 mm to 3 mm, the bearing capacity of sandwich slab increases by 59% in normal use and 84% in ultimate bearing capacity, stiffness increased by 61%.The variation of polyurethane density has little influence on the bearing capacity and stiffness of sandwich slab. the density changes from 45 kg/m3 to 90 kg/m3, the bearing capacity of sandwich slab increases by 12% in normal use, only 2% in ultimate bearing capacity, and 12% in stiffness.
Dynamic Response Analysis of Steel Structure Based on the Combination of Vibration Reduction and Isolation
Heng Kou, Qianrui Chen, Yu Song, Wenkai Chen, Peihong Chi
2022, 37(8): 17-25. doi: 10.13206/j.gjgs21111802
Abstract:
Based on the idea that the combination of seismic isolation and isolation could provide multi-channel seismic fortification for the structure, an application technology suitable for building high-rise steel structures in high-intensity areas was proposed. In order to study the shock absorption characteristics of high-rise steel structures with seismic and isolation devices, the layout rules of the inter-story isolation positions were compared and analyzed. The scheme arranged on the top of the column of the 4 th floor(at the sudden change in stiffness). The SAP 2000 finite element model of the traditional seismic structure(modelⅠ), the inter-story isolation structure(model Ⅱ) and the combined seismic isolation structure(model Ⅲ) was established, and the response spectrum analysis was carried out to obtain the natural vibration periods of the three structures, and the 8-degree(400 cm/s2) and The ground motion of 8 and a half(510 cm/s2) was calculated and analyzed, and the interstory displacement, floor acceleration, interstory shear force, hysteresis curves of isolation bearings and anti-buckling braces of the three structures were obtained by the groud motion analysis of 8-degree and 8 and a half degree of rare earthquake.
The results showed that:comparing model Ⅰ and model Ⅱ, under the action of the 8-degree(400 cm/s2) and 8 and a half(510 cm/s2) earthquakes, the displacement decreases of the Model III isolation layer were 10.5% and 14.8%, respectively; under the 400 cm/s2 and 510 cm/s2 earthquakes, the peak value of floor acceleration of model I increased gradually; compared with model I, the relative acceleration peak value of model II and model III decreased significantly at floors above the isolation layer, and the variation between floors was not large; compared with model II, the acceleration of model III was lower at floors below the isolation layer; the relative acceleration of the top layer of the model II structure was about 50% lower than that of the model I, and the relative acceleration of the top layer of the model III structure reduced by 60% compared with that of the model I; the maximum shear force ratio of the floors below the seismic isolation layer of the model II and model III under the action of 400 cm/s2 was 0.710 and 0.613 respectively. and 0.449 and 0.427 for the floors above the seismic isolation story, respectively; under the action of 510 cm/s2, the maximum shear ratios of the floors below the seismic isolation story of model II and model III were 0.741 and 0.602, respectively, while those above the seismic isolation story were 0.421 and 0.389, respectively; the hysteresis curve of the lead-core isolation bearing(LRB) under rare earthquakes was full, and the maximum displacement reached 161.6 mm(510 cm/s2) and 124.5 mm(400 cm/s2), which consumed most of the seismic action. The hysteresis loop of model Ⅲ used lead-core isolation was smaller than that of model II, which indicated that the bottom buckling bracing(BRB) shared the part of the seismic action, and the hysteresis loop under 500 cm/s2 was significantly larger than that of 400 cm/s2. It showed that the shock absorption effect of the structure arrangement of the shock isolation device on the upper floors was more significant, and from the perspective of the whole structure, the shock absorption effect of the combined seismic isolation structure was better than that of the floor isolation structure, and the isolation was reduced under the action of higher intensity earthquakes. The seismic combination showed better shock absorption performance and could provide more safety for the structure.
Design
Design Analysis of Single Layer Saddle Net for Swimming Pool of Desheng Sports Center in Shunde
Jinyu Chen, Tong Ou, Xuebing Liu, Zhengrong Jiang
2022, 37(8): 26-34. doi: 10.13206/j.gjgs21071901
Abstract:
Shunde Desheng Sports Center is the first time to adopt the single-layer saddle shaped cable net structure in the coastal typhoon high incidence area in China. The plane of cable net is 109 m×71 m ellipse, and the rise height of cable net is 8 m. The support system and lateral force resistance system of cable net roof steel structure are composed of peripheral V support and roof ring beam. Two high-strength sealing cables with a diameter of 65 mm and 45 mm are respectively used for the longitudinal stress cable and the lateral stability cable of the cable network structure. The ring beam is a giant rectangular beam 1 m×2 m. The roof system is a three-layer membrane system. As the saddle shaped cable net roof used for the first time in the coastal strong typhoon area, the pretension of the main cable and the secondary cable must be determined through fine shape finding and force finding, and the relative proportion of the deflection and the cable internal force under the combination of "constant load+ live load" and "constant load+ wind load" must be closely coordinated, so that the upward and downward deformation are balanced. After the structural system and form finding and force finding are preliminary determined, the detailed design of the components is carried out and the rationality of the structural scheme is verified through static analysis, stability analysis, continuous collapse prevention analysis, construction simulation analysis and large earthquake elastic-plastic analysis. The safety redundancy and construction sequence of the cable network are very important to the formation of the structural system. The nonlinear static analysis method is adopted for the cable breaking analysis in the design, and it is suggested to adopt the tensioning scheme of high-altitude sliding cable + tensioning stable cable from the perspective of engineering design. According to the stress characteristics of the structure, the surrounding V supports bear large two-way axial force and are exposed and visible. Therefore, the innovative two-way thrust bearing node is adopted to ensure the structural stress and the architectural aesthetics, and ensure the safety and redundancy of the node. The design of roof steel structure and cable structure can meet the requirements of Steel Structure Design Standard(GB 50017-2017), and can effectively realize the architectural form.
Construction Technology
Analysis of Static Performance and Construction Process of Bi-Directional Cable-Supported Composite Floor Structure
Zhenzhou Bao, Qi An, Yuhao Dong
2022, 37(8): 35-46. doi: 10.13206/j.gjgS22062101
Abstract:
With the large-scale construction of large public buildings, multi-storey large span structure comes into being. The biggest feature of the structure is that the span of floor structure is large. At present, there are four kinds of structural systems that can be applied to long-span floor, namely hollow sandwich floor, steel truss(net rack) composite floor, cable-supported floor and prestressed floor. In order to further improve the span capacity of floor structure and improve the force transmission efficiency, a new type of long-span floor structure, namely bi-directional cable-supported composite floor structure(BCSCFS), is presented in this paper. Through the numerical simulation method, the static performance of new type of structure system and the force transmission mechanism had carried out firstly, and the law over space and time in the construction and service phase in terms of the support reaction force, cable force, steel beam force and the internal force of concrete slab were discussed. Secondly, by comparing with the conventional composite floor structure, the improvement effect of the new floor structure in span capacity was studied. Finally, the design method of the new structure was discussed, and the influence of neglecting the construction process on the design result was studied.
The results show that:the horizontal normal support reaction force in the concrete construction stage increased significantly, and the horizontal reaction direction at the middle position and side position of the boundary is opposite. In the use stage, the normal horizontal support reaction force is the largest, followed by the vertical reaction force, tangential horizontal reaction force is the smallest. In the construction process, the horizontal displacement of sliding support changes little. The general trend of the cable force in the construction process is gradually increased, but there is a certain drop in the tension stage in the middle position. Except the tension stage, the cable force in the middle position is large and that in the two sides is small in the other construction and service stages. The axial force of steel beam is pressure in the stage of steel structure assembling and cable tensioning. In the stage of concrete construction and service, the middle part of steel beam is strained and the two sides are pressed. The bending moment of steel beam is mainly positive bending moment in steel structure assembling stage and negative bending moment in cable tensioning stage. In the concrete construction stage and the use stage, the middle of the steel beam is positive bending moment, the two sides are negative bending moment. The concrete slab is under pressure at all stages, and the bending moment is small. Compared with the conventional bi-directional composite floor, the horizontal reaction force, structural axial force, bending moment and vertical deformation of the support are greatly reduced, and the static performance is better than that of the conventional bi-directional composite floor. When analyzing the static performance of BCSCFS, there is a large deviation between the calculation results of the direct method and the actual situation, and most of the internal forces of the key structure part are relatively small. There is a certain safety hazard for the structure design, so it is recommended to adopt the method considering the construction process in analysis of structure in the design.
Design Discussion
Hazard of Weak Panel Zone in Frame Design
Genshu Tong
2022, 37(8): 47-49. doi: 10.13206/j.gjgS22082001
Abstract:
Panel zone must be checked in seismic design of frame, the paper discussed the hazards of weak panel zone and proposed equations for more strong panel zone.
Hot Spot Analysis of Steel Structures
2022, 37(8): 50-50.
Abstract: