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http://dx.doi.org/10.4334/JKCI.2016.28.6.655

Effective Moment of Inertia of Flexural Members Based on the Concrete Stress-Strain Curve in EC-2  

Yum, Hwan-Seok (School of Architecture, Gwangju University)
Kim, Woo (Dept. of Civil Engineering, Chonnam National University)
Publication Information
Journal of the Korea Concrete Institute / v.28, no.6, 2016 , pp. 655-663 More about this Journal
Abstract
The present study shows the moment-average curvature relationship and effective inertia moment of RC beams obtained from the nonlinear analysis based on the parabola-rectangular stress-strain curve defined in EC-2 code. The variables examined are concrete strength and steel ratio, and moment-average curvature relationship and effective inertia moment obtained are compared with those of the current KCI provisions. As the results of the comparison, the followings could be said: Since the KCI provisions(the Branson method) were originally derived based on the experimental data ranged from 2.2 to 4 of $M/M_{cr}$ and 1.3 to 3.5 of $I_{ut}/I_{cr}$, thereby within these ranges the inertia moments obtained from the nonlinear analysis are closely agreed with those predicted by the Branson method. However, beyond those range the remarkable difference could be found between the two results. In particular, for beams having low steel ratio the inertia moment resulted from the nonlinear analysis are significantly smaller than those obtained from the KCI(Branson) method. This result may imply that the deflection of lightly reinforced members, such as slabs in buildings, becomes much larger than those calculated according to the current design provisions.
Keywords
EC-2; parabola-rectangular stress-strain curve; nonlinear analysis; bending moment-average curvature relationship; effective inertia moment;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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