Research on Lateral Stiffness of Embedded Wall Board Steel Frame Structure

Steel structure buildings have the characteristics of factory production, good seismic performance, recyclability, environmental protection and other characteristics. They are widely used in prefabricated buildings. In prefabricated steel structure buildings, embedded wallboards are often used as filling walls for steel frame structures. However, in the existing structural design theory, the period reduction factor is generally used to consider the influence of embedded wallboards on the lateral stiffness of steel frame structures. Sometimes, this causes a large difference between the simulated lateral stiffness of the frame and the actual stiffness, which is not conducive to refined engineering design. It is necessary to further study the influence of embedded wallboards on the lateral stiffness of steel frames. Therefore, in this context, in order to further study the changes of the lateral stiffness of steel frames caused by different influencing factors in the discrete connection between embedded wallboard and steel frame, ABAQUS finite element software was used to establish a structural model of steel frame with embedded autoclaved lightweight concrete(ALC) wallboard. The influence of the number of connection nodes and the stiffness ratio of the wallboard to the embedded wallboard steel frame structure(referred to as EWSF structure) was considered when connecting the ALC wallboard to the frame beam, the frame column, and the frame beam column together.
The results show that the lateral stiffness of EWSF structure is greatly improved compared with the steel frame structure without wallboard. According to different connection conditions, the improvement degree can reach 4 to 6 times. The results of multi parameter analysis show that the change of connection conditions has a greater impact on the overall lateral stiffness of EWSF structure. With the increase of the number of connection nodes, the initial lateral stiffness of EWSF structure when the ALC wallboard is connected to the frame beam increases more significantly than when it is connected to the frame column. Compared with the case when the ALC wallboard and the frame beam column are connected separately, the effect of the joint connection of the ALC wallboard and the frame beam column on improving the lateral stiffness of EWSF structure is more significant. When the structure has fewer connection nodes, the change of beam column connection has little effect on the lateral stiffness of EWSF structure. The lateral stiffness of EWSF structure increases with the decrease of the stiffness ratio of the embedded wallboard to the steel frame. Based on the model analysis and theoretical derivation of the influence of factors such as the number of connection nodes and the stiffness ratio on the initial lateral stiffness of the structure, the influence coefficient β of the initial lateral stiffness of the structure when the embedded wallboard is fully rigid connected to the steel frame and the influence coefficient α of the initial lateral stiffness of the structure when the embedded wallboard is discrete connected are introduced respectively. And the formula for calculating the initial lateral stiffness of the structure is proposed. The calculation result is consistent with the finite element analysis result, which can provide a certain reference for engineering design.