| PaperNO | Paper / Abstract |
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SE11-001
10:50
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11:10
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SEISMIC PERFORMANCE OF PERIODIC METAMATERIAL BARRIERS
The periodic barrier, which is infilled with periodic metamaterial, is an emerging research topic in structural engineering for its frequency-selective property. In this research, finite element (FE) simulation is conducted to investigate the frequency-selective properties of the periodic barrier consisting of concrete and rubber and subjected to seismic loading. First, the theoretical frequency band gaps are calculated based on a one-dimensional unit cell. Second, the simulation of the periodic barrier subjected to the excitation is carried out using the commercial software, ABAQUS. The boundary condition, element choice and mesh size are illustrated in detail. This study introduces a new approach to evaluate the seismic performance of the periodic barriers by reducing the computing time. The comparison with sweep-frequency simulation indicates adequate accuracy of the proposed approach. The influence of key variables, including the barrier depth, number of the unit cells, the excitation direction, and the distance from the vibration source to the periodic barrier, are investigated in detail. A scheduled large-scale field test is briefly described at the end of this paper.
Hsuan Wen Huang, Jiaji Wang, F.-Y. Menq, Yi-Lung Mo, K. Stokoe
band gap, finite element, large-scale field test, periodic barrier, periodic metamaterial
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SE11-021
11:10
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11:25
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EXPERIMENTAL INVESTIGATION OF THE HYSTERETIC PERFORMANCE OF SELF-CENTERING BUCKLING-RESTRAINED BRACES WITH FRICTION FUSES
The current dual-tube self-centering buckling-restrained brace (SC-BRB) is limited by the elastic elongation of the tendons. When the lateral deformation of existing dual-tube SC-BRBs exceeds 2.7% of a typical building story height, the tendons will be fractured, and this fracture will lead to a sudden drop of the bearing capacity of the brace and loss of the self-centering capacity. In this paper, an SC-BRB with a friction fuse (SC-BRB-FS) is proposed by introducing a friction device at the end of the brace to increase the deformation capacity of the dual-tube SC-BRB. At the same time, a bracing specimen is built for a quasi-static test. Activation of the friction fuse can efficiently increase the deformation capacity of the brace. When the displacement reaches 36 mm (corresponding to a story drift of 4%), the tendons are still not damaged. The nonlinear dynamic time-history analysis of the structure shows that compared with the fracture of BFRP tendons, the use of a friction fuse not only restrains the soft-story effect and reduces the collapse probability of the structure but also reduces the residual deformation of the structure.
Qin Xie, Zhen Zhou
braced frame, deformation capacity, friction fuse, seismic response, self-centering
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SE11-022
11:25
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11:40
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CYCLIC BEHAVIOR OF SLENDER RC STRUCTURAL WALLS WITH HIGH STRENGTH STEEL REINFORCEMENT
The upper limit on the specified yield strength specified by ACI 318-14 for longitudinal and shear reinforcement in special RC structural walls is intended to prevent brittle failure and control crack width. This study investigated the seismic behavior of slender RC walls with high-strength steel reinforcement and concrete materials. Experimental tests were conducted to study the impact of yield strength of reinforcements (420 MPa and, 790 MPa), compressive strength of concrete (55 MPa and, 70 MPa) and loading history (monotonic and cyclic loads) on the cyclic behavior of structural walls with an aspect ratio of 2.75 under combined lateral and axial loads. The behavior of the walls was discussed in terms of lateral strength, stiffness, failure pattern, and drift capacity.
Chung-Chan Hung, Yu-Chen Chou, Hsin-Jui Hsiao
cyclic loads, high-strength reinforcement, reinforced concrete, structural wall
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SE11-024
11:40
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11:55
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Structural Performance of Reinforced Concrete Members with Non-Structural Walls without Anchorage of Wall Reinforcement
In 2016 Kumamoto earthquakes, reinforced concrete buildings which were expected to be used as disaster base facilities during earthquakes suffered severe damages and lost their functions. For evacuation activity, capability of continuous use can be imparted to the buildings. A guideline of design of buildings for disaster base facilities provided by National Institute for Land and Infrastructure Management prescribes that non-structural reinforced concrete walls like wing walls and hanging/spandrel walls can be utilized as structural elements to increase ductility and capability of continuous use of buildings. However, cracks and large plastic deformation of non-structural concrete walls impact serviceability and visual appearance. In order to reduce expansion of cracks on the non-structural walls, the authors proposed new detail of reinforced concrete member with non-structural walls, where longitudinal wall reinforcement is not anchored. The objective of this paper is to investigate seismic performance of members with non-structural walls which has new detail. Experimental tests of reinforced concrete column and beam with or without non-structural walls were carried out. The parameters are presence of non-structural walls and amount of confinement reinforcement placed at the wall boundary. The amount of confinement reinforcement is determined according to specification of confinement reinforcement to boundary element in ACI 318-14 code and design standard of Architectural Institute of Japan. From the experimental test results, following conclusions were obtained. 1) The increasing of maximum shear strength of members with non-structural walls was verified; 2) The load vs drift angle relationship of the members with non-structural walls where longitudinal wall reinforcement is not anchored demonstrates high ductility; however, difference attributed to amount of confinement reinforcement is not found on the relationship and crack pattern; 3) By elimination of anchorage of longitudinal wall reinforcement, dominant large crack opening occurred at the wall boundary; however, large strength degradation was not observed in performance curve; 4) The maximum horizontal load of the specimen can be predicted by cross-sectional analysis and the authors proposed a simple equation to predict that with enough accuracy.
Yo Hibino, Yasushi Sanada, Koichi Kusunoki
anchorage, cracks, non-structural walls, seismic performance, wall reinforcement
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