Comparative Study on the Controlling Parameters for the Effective Flange Width of RC T-beams

Abdelaziz, Mahmoud; Abdel Khalik, Abdel Hakim; Afefy, Hamdy; Kotb, Mahmoud

doi:10.21608/asge.2022.153856.1036

Comparative Study on the Controlling Parameters for the Effective Flange Width of RC T-beams

Document Type : Original Article

Authors

¹ Structural Engineering Department, Faculty of Engineering, Tanta University.

² Structural Engineering Department, Faculty of Engineering, Tanta University, Egypt.

10.21608/asge.2022.153856.1036

Abstract

A virtual T-section may be formed and considered in the design process of reinforced

concrete (RC) beam, when a part of the topping slab and the projecting beam acts as a single

unit in resisting the flexural positive moment. Based on an extensive overview on the

controlling parameters adopted by different design standards for calculating the effective

flange width of the T-section,15 design codes were considered; ACI 318-14, ASC 2004, AS

3600-2017, BNBC 2015, BS 8110-1:1997, CSA A23,3-04, ECP 203-2018, Eurocode 8-2004,

IRAQ 1-78, IS 456:2000, JSCE 2007, MS 2010, NZS 3101:2006, TS 500 and SBC 304-2007.

The considered parameters were noticed to be varied from code to another. It was noticed

that ACI 318-14, BNBC 2015, NZS 3101:2006 and SBC 304-2007 codes estimate the

effective flange width regardless of distance between moment inflection points (beam

continuity) inspite that others codes consider such effect. An illustrative example is presented

in order to compare the results of different standards considering the continuity effect. It was

found that for the same case of loading and concrete dimensions, significant variations were

observed in all cases. Besides, dissimilar values were stipulated by design standards for the

distance between inflection points. Therefore, this paper also aims to shed a light on the exact

value of the factor multiplied by the span length to obtain the distance between inflection

points. A linear finite element analysis is implemented to analyze the case study with 2 spans,

3 spans, 4 spans …. etc.

Keywords