نوع مقاله : یادداشت فنی
نویسندگان
دانشکده مهندسی عمران و محیط زیست- دانشگاه تربیت مدرس
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
Near-fault earthquakes have different properties compared to far-fault earthquakes because of forward-directivity, long-period pulses and fling-step motion. Near-fault ground motion can cause extensive structural damage compared to far-fault ground motion. The concentration of energy at short intervals and in pulses of near-fault ground motion causes impulsive movement. Application of systems with high ductility and energy absorption subjected to near-fault earthquakes is inevitable. In the buckling-restrained braced frames, yielding of steel core, either in tension or compression, helps to absorb the high magnitude of energy. The usual configuration of these systems is concentric. Application of ductile beam splices and buckling-restrained braces in eccentric configurations makes it possible to use the architectural benefits of eccentrically braced frames and also the design benefits of buckling-restrained braced frames. In this bracing system, brace elements provide the lateral stiffness of steel frames and are designed to undergo large inelastic axial deformations. Link beams should remain elastic, while transferring ultimate brace forces into the columns. In addition to the properties of the eccentric buckling-restrained frames, such as appropriate dynamic performance and ductility ratio, the system has the capability to be easily repaired after an earthquake because the structural damage is concentrated in the braces and not in the link beam. Evaluation and comparison of the dynamic performance of these eccentrically braced frames and buckling-restrained braced frames subject to near-fault and far-fault ground motion is the aim of this thesis. To reach the objective, incremental inelastic dynamic analyses of 2D frames with different heights and length of span are performed, and parameters, such as average maximum inter story drift, input energy and limit states, from the incremental dynamic analysis curves for both bracing systems are compared. Results indicate that eccentric buckling restrained braced frames for high seismic regions and subject to near-fault ground motion have better dynamic performance compared to eccentrically braced frames.
کلیدواژهها [English]
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