Study on Buckling-Restrained Braces Having Large Cumulative Plastic Strain Energy Ratio

Abstract

The authors have studied the buckling-restrained brace providing stable hysteretic characteristic even under high-strain conditions. Structural performance of the buckling-restrained brace is represented by the evaluation formula that is the lower limit of the cumulative plastic strain energy ratio. However, when the duration of earthquakes gets extraordinarily longer, it is necessary to research and develop a new buckling-restrained brace with more high capacity of energy dissipation. In this paper, our past studies are analyzed and the conditions of high-performance of buckling-restrained braces are extracted. The considered buckling-restrained brace is tested. As a result, the buckling-restrained brace having large cumulative plastic strain energy ratio has been proposed.

Performance Evaluation of Buckling-Restrained Braces Installed in a Mid-Rise Steel Structure

“…Overview of specimens. The top view and cross section of specimens used in past studies [1][2][3] are presented in Fig. 2.…”

“…To date, many comparative performance tests have been conducted. As a result, the past study proposed equations for finding the lower limit of the performance of the BRBSM based on energy absorption performance [1] and presented its fatigue performance [2,3]. Fig.…”

Proposal and application of structural soundness monitoring system for the buckling‐restrained brace using steel mortar planks

“…In specimens where the core plate underwent a tensile fracture, the permissible value ω r is the lower limit of the evaluation formula of the cumulative plastic strain energy ratio and is expressed by Eq. ( 3) [29]. This lower limit is obtained by the incremental cyclic loading test at a strain amplitude of up to 3.0 %, including the effect of the strain hardening of the core plate.…”

Effects of the clearance between the core plate and restraining part on the structural performance of the buckling‐restrained brace using steel mortar planks

“…The clearance is measured from the outer perimeter of the restraining part after assembling riods and long durations. A higher-order buckling mode occurring in the core plate is influenced by clearance, core plate width-to-thickness ratio, slenderness ratio and restraining index [14,15]. For this clearance adjustment of the BRBSM, a construction method has been adopted where a clearance adjustment material (butyl rubber) is attached to the entire surface of the core plate.…”

“…4 were fabricated to confirm that the specified clearance ratio can be assured by the clearance adjustment construction described above. The clearance ratio described in section 3.1 is set to 4-20 % based on previous research [13][14][15] where the clearance adjustment materials were applied to the entire surface of the core plate. For all the specimens, butyl rubber (1 × 100 × 30 mm) was attached to both sides of the core plate as the clearance adjustment material.…”