Research Article
High-Performance Steel Bars and Fibers as Concrete Reinforcement for Seismic-Resistant Frames
Table 5
Properties of SDOF systems considered.
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aGrade-670 and Grade-830 systems represent equivalent alternatives to Grade-410 systems. All systems target identical strength; however, the stiffness of Grade-670 or Grade-830 systems is 0.75 or 0.50 times the stiffness of Grade-60 systems. In all cases, the postyield stiffness was defined as 5% of the initial stiffness. bTarget periods of vibration for Grade-410 systems are set to 0.6, 0.9, and 1.2 s for a unit mass, from which the stiffness is derived. The stiffness of Grade-670 or Grade-830 systems is 0.75 or 0.50 times that of Grade-410 systems. cLinear-response acceleration (divided by g) of a 5%-damped SDOF system of period . It is defined using , where and , refer to ASCE/SEI 7-10 [20]. dYield force, , of nonlinear SDOF system (of initial period ) divided by the force induced in a 5%-damped linear SDOF system of period . e, where is the strength ratio and is the spectral acceleration coefficient obtained from the design spectrum (5% damping coefficient) for a system of period . The value of corresponds to the yield strength, , divided by the weight, , of the SDOF system. |