• Journal of Korean Society of Steel Construction
• /
• v.16 no.5 s.72
• /
• pp.629-639
• /
• 2004

A steel frame is one of the most commonly used structural systems due to its resistance to various types of applied loads. Many studies have been conducted to investigate the effects of several parameters, such as connection flexibility, the boundary condition of each support, and beam-to-column stiffness ratio, on the characteristic behavior of a frame. Based on the results of these studies, several design methods have been proposed. This research focused on the number of bolts on the rotational stiffness of a double-angle connection, and its effect on the story drift of a frame. To achieve these purposes, a simplified analytical model was proposed. Several experimental tests were also conducted to obtain the rotational connection stiffness of each double-angle connection.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.22 no.5
• /
• pp.501-507
• /
• 2009

By using topology and shape optimization, a theoretically optimum FRP deck was proposed. Firstly, a topologically optimal shape, truss-like structure without hinges, was found. A truss-shape frame is the most ideal structure when subjected to a concentrated force at the center of simply supported beam. An armature was found at the point joining horizontal chord and diagonal chord, which was used as a new design variable. Secondly, optimum value of each variable was decided through shape optimization using genetic algorithm. To compare it with existing commercial FRP decks, shape optimization was performed by fixing the height of FRP decks. To verify the performance of the FRP deck proposed in this study, a finite element analysis was performed. As a result, it satisfies serviceability and safety guide lines of FRP decks.

• Journal of Korean Society of Steel Construction
• /
• v.23 no.3
• /
• pp.261-273
• /
• 2011

Recently, the demands for steel frame are increasing because of the trend and due to the demand for bigger and higher buildings. In the analysis of typical steel frame, connections are based on the idealized fixed or pinned connection. A fixed connection assumes that the relative angle of each member before deformation is the same after the transformation. Therefore, the stiffener reinforces the connection to sufficient rigidity and stability of the panel zone. In the economical aspect, however, the necessity of connection that the stiffener reinforcement has omitted is increasing due to the excessive production as well as labor costs of connection. In contrast, pinned connection is assumed that bending moments between the beams and columns do not transfer to each member. This is easy to make in the plant and the construction is simple. However, the structural efficiency is reduced in pinned connection because connection cannot transfer moments. The introduction of this semirigid process can decide efficient cross-sectional dimensions that promote ease in the course of structural erection, as performed by members in the field-a call for safety in the entire frame. Therefore, foreign countries exert efforts to study the practical behavior and the results are applied to criterion. This paper analyzes the semirigid connection of domestic steel by design specifications of AISC/LRFD and make data bank that pertain to each steel. After wards, the results are compared to those of idealized connection; at the same time, this paper presents a design method that matches economic efficiency, end-fixity, and rotational stiffness.