Techno Press
Tp_Editing System.E (TES.E)
Login Search


scs
 
CONTENTS
Volume 5, Number 5, October 2005
 

Abstract
The response of single story buildings and other case studies are investigated to observe trends in response and to develop a better understanding of the impact of some design parameters on the seismic response of CBF. While it is recognized that many parameters have an influence on the behavior of braced frames, the focus of this study is mostly on quantifying energy dissipation in compression and its effectiveness on seismic performance. Based on dynamic analyses of single story braced frame and case studies, it is found that a bracing member designed with bigger R and larger KL/r results in lower normalized cumulative energy, i.e., cumulative compressive energy normalized by the corresponding tensile energy (SEC/ET), in both cases.

Key Words
seismic response; concentrically braced frames; non-linear dynamic analyses; energy dissipation; compression members; slenderness ratios; R factor.

Address
Kangmin Lee; Department of Architectural Engineering, Chungnam National University, 220 Gung-dong, Yuseong-gu, Daejeon 305-764, KorearnMichel Bruneau; 212 Ketter Hall, Department of Civil, Structural, and Environmental Engineering, StaternUniversity of New York at Buffalo, Buffalo, NY 14260, USA

Abstract
This paper presents the experimental and theoretical results of the viscoplastic response and collapse of 316L stainless steel tubes subjected to cyclic bending. The tube bending machine and curvature-ovalization measurement apparatus, which was designed by Pan et al. (1998), were used for conducting the cyclic curvature-controlled experiment. Three different curvature-rates were controlled to highlight the characteristic of viscoplastic response and collapse. Next, the endochronic theory and the principle of virtual work were used to simulate the viscoplastic response of 316L stainless steel tubes under cyclic bending. In addition, a proposed theoretical formulation (Lee and Pan 2001) was used to simulate the relationship between the controlled cyclic curvature and the number of cycles to produce buckling under cyclic bending at different curvature-rates (viscoplastic collapse). It has been shown that the theoretical simulations of the response and collapse correlate well with the experimental data.

Key Words
viscoplastic response; viscoplastic collapse; 316 L stainless steel tubes; cyclic bending; endochronic theory; moment; curvature; ovalization.

Address
Kao-Hua Chang; Department of Engineering Science, National Cheng Kung University, Tainan, Taiwan, R.O.C.rnChien-Min Hsu; Department of Art-Craft, Tung Fang Institute of Technology, Kao Hsiung County, Taiwan, R.O.C.rnShane-Rong Sheu; Department of Automation and Control Engineering, Far East College, Tainan, Taiwan, R.O.C.rnWen-Fung Pan; Department of Engineering Science, National Cheng Kung University, Tainan, Taiwan, R.O.C.

Abstract
An experimental study was conducted to develop a new base plate anchorage system for concrete filled tubular column under an axial load and a moment. The column was connected to a concrete foundation using ordinary deformed reinforcing bars that are installed at the inside and outside of the column. In order to investigate the moment resisting capacity of the system, horizontal cyclic loads are applied until the ultimate condition is reached with the axial load held constant. To derive a design method for moment resisting capacity, the reinforced concrete section approach was investigated with the assumption of strain compatibility. The results by this approach agreeded well with those of experiments when the bearing pressure of confined concrete and tangent modulus of steel bars are assumed appropriately. Also, it was found that the column interaction curve can be used to predict the yield strength of the base plate system.

Key Words
column base plate; reinforcing bar anchor; moment resisting capacity; reinforced concrete section method; interaction curve.

Address
Yong-Myung Park; Department of Civil Engineering, Pusan National University, 30 Jangjeon-dong, Geumjeong-gu, Busan 609-735, KorearnWon-Sup Hwang; Department of Civil Engineering, Inha University, 253 Yonghyun-dong, Nam-gu, Incheon 402-715, KorearnTae-Yang Yoon and Min-Oh Hwang; Civil Engineering Research Team, Research Institute of Industrial Science and Technology, 79-5 Youngcheon, Dongtan, Hwaseong, Gyeonggi-do, 445-813, Korea

Abstract
This work introduces to the international scientific community the Chinese Code on fire safety design of steel building structures. The aim of the Code is to prevent the structure of a steel building subjected to fire from collapsing, ensure safe evacuation of building occupants, and reduce the cost for repairing the damages of the structure caused by fire. The main contents of the Code is presented in this paper, including the fire duration requirements of structural components, fundamental requirements on fire safety design of steel components, temperature increasing of atmosphere and components in fire, loading effect and capacity of various components in fire, and procedure for fire-resistant design of steel components. The analytical approach is employed in the Code and the effectiveness of the Code is validated through experiments.

Key Words
fire-resistance; steel structures; design code.

Address
Department of Structural Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, P.R. China

Abstract
This study presents the strength of braced and unbraced cold-formed steel wall frames consisting of several wall studs acting as columns, top and bottom tracks, and bracing members. The strength and the buckling mode of steel wall frames were found to be different due to the change of bracing type. In addition, the spacing of wall studs is a crucial factor to the strength of steel wall frames. The comparisons were made between the test results and the predictions computed based on AISI Code. The related specifications do not clearly provides the effective length factors for the member of cold-formed steel frame under compression. This paper proposes effective length factors for the steel wall frames based on the test results. A theoretical model is also derived to obtain the modulus of elastic support provided by the bracing at mid-height of steel wall frames in this research.

Key Words
cold-formed steel; wall frame; channel bridging; strap bracing; effective length factor.

Address
Chi-Ling Pan; Department of Construction Engineering, Chaoyang University of Technology, 168, Gifeng E. Rd., Wufeng, Taichung County, Taiwan, R.O.C.rnJui-Lin Peng; Department of Construction Engineering, National Yunlin University of Science & Technology, 123, Section 3, University Road, Touliu, Yunlin, Taiwan, R.O.C.


Techno-Press: Publishers of international journals and conference proceedings.       Copyright © 2017 Techno-Press
P.O. Box 33, Yuseong, Daejeon 34186 Korea, Tel: +82-42-828-7996, Fax : +82-42-828-7997, Email: info@techno-press.com