International Research Journal of Innovations in Engineering and Technology - IRJIET International Open Access, Monthly, Peer Reviewed, Reputed Journal ISSN (online): 2581-3048

Impact Factor (2025): 6.9

DOI Prefix: 10.47001/IRJIET

Investigation of Short Term Deflection of Reinforced Concrete Flat Slabs

Abstract

This research is dedicated to correct the Short Term of concrete Flat Slab deflection calculated based Branson equation used in both on ACI 318 code and ECB-207 code, Due to linear material behavior, sudden reduction of Effective inertia after cracking and 1D action of this equation(was conducted after studies in simply supported beams), calculated deflection  from this equation is vastly overestimated form actual behavior, so a correction factor for deflection calculated   From Branson equation is the main objective for this research. After verification of ABAQUS Software as FEM Simulation of Flat slab behavior, a parametric study is conducted to Make a charts for the correction Factor of deflection calculated using Branson equation. Assuming that Fc’=30mpa And Fy=400mpa, A parametric study is made on total of 75 Square simply supported Flat slab, Those slabs are modeled using both SAFE (using ACI-318 Cracking Criteria) And ABAQUS (Using CPDM Behavior for Concrete model) to Present Load Deflection Difference of Each case on each model, then Normalized Deflection (∆cracked/∆ABAQUS) is calculated for each λ (Mact/Mcr) to represent the different ratios of corrections over variance of super imposed dead load on slab. Finally 15 charts were presented for different cases of lower& top reinforcement ratios to correct the deflection calculated From CSISAFE (Using ACI318 Equation and Cracking Criteria).

Country : Egypt

1 Prof. Dr. Ayman Aboeolfotooh Embaby2 Prof. Dr.Amin Saleh Aly3 Dr.Sherif Kamal Elwan4 Amr Mohamed Elshafey

  1. Professor, Structural Engineering Dept., Faculty of Engineering, Ain Shams University, Cairo, Egypt
  2. Professor, Structural Engineering Dept., Faculty of Engineering, Ain Shams University, Cairo, Egypt
  3. Associate Professor, Structural Engineering Dept., The Higher Institute of Engineering, El Sherouk City, Cairo, Egypt
  4. Master of Science Student, Structural Engineering Dept., Faculty of Engineering, Ain Shams University, Cairo, Egypt

IRJIET, Volume 3, Issue 9, September 2019 pp. 32-38

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