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http://dx.doi.org/10.12652/Ksce.2011.31.1A.035

Limit Span/Depth Ratio for Indirect Deflection Control in Reinforced Concrete Flexural Members  

Choi, Seung-Won ((사)한국콘크리트학회 콘크리트공학연구소)
Kim, Woo (전남대학교 토목공학과)
Publication Information
KSCE Journal of Civil and Environmental Engineering Research / v.31, no.1A, 2011 , pp. 35-41 More about this Journal
Abstract
In concrete structural design provisons, two methods are normally provided to control deflection; direct method and indirect method. It is more efficient to use the indirect deflection control by which the span/depth ratio is limited not to exceed an allowable deflection limit. Because actual deflections are affected by many causes, it is complicated to evaluate actual deflections. In this study, limit span/depth ratios are derived from the deflection calculated directly at the serviceability limit state in RC members. The deflection is obtained from using average curvature, which depends on materials model used. The main variables examined are tension stiffening effect, concrete strength, cross section size and compressive steel ratio. It could be appeared that more analytical consistency is secured to use the 2nd order form of tension stiffening effect. And the limit span/depth ratio is dependent on material strength, tensile and compressive steel ratio but it is independent on cross-section size.
Keywords
indirect crack control; limit span/depth ratio; tension stiffening effect; materials strength; cross-section size;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
연도 인용수 순위
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