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1. REINFORCED CONRETE (1)
(CE411)
Chapter 3-c
Flexural Analysis and Design of Beams
Instructor:
Eng. Abdallah Odeibat
Civil Engineer, Structures , M.Sc.
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2. T - BEAMS
 In case of monolithic casting and extension of
stirrups and bent bars up to slabs; T-beams are
resulted
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3. 3

4. 4

5. EFFECTIVE FLANGE WIDTH
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6. STRENGTH ANALYSIS
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7. A. NEUTRAL AXIS WITHIN THE FLANGE
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 T-beam is treated as rectangular
beam

8. B. NEUTRAL AXIS WITHIN THE WEB
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bw
bw

9. B. NEUTRAL AXIS WITHIN THE WEB
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+
bw bw

10. B. NEUTRAL AXIS WITHIN THE WEB

11. ANALYSIS
 For analyzing the capacity of a T beam with
known concrete dimensions and tensile steel
area, it is reasonable to start with the
assumption that the stress block depth a does not
exceed the flange thickness. In that case, all
ordinary rectangular beam equations apply, with
the beam width taken equal to the effective width
of the flange. If, upon checking the assumption, a
proves to exceed (hf) , then T beam analysis must
be applied (slides 8,9,10).
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12. DESIGN
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13. EXAMPLE (ANALYSIS)
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 Flange width = 700 mm
 Flange depth = 150 mm
 Web width = 250 mm
 Total depth = 750 mm
 As = 6ø32 mm (2 layers)
 d = 650 mm
 fc’= 21 MPa
 fy= 420 MPa
 Find Mu ?

14. SOLUTION:
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15. EXAMPLE (DESIGN)
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 Span length = 7.5 m
 Mu = 725 kN.m
 fy = 420 MPa
 fc’ = 21 MPa

16. SOLUTION :
 Determine effective flange width:
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17. SOLUTION :
 Determine area of steel:
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18. SOLUTION :
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19. SOLUTION :
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For Mu = 209.6 *10^6 N.mm, fc’ = 21 MPa , fy = 420 MPa
b=bw= 275 mm , d= 500 mm , Ф =0.9 (to be checked)
ρ = 0.00903 , check
Asw = ρ b d = 1241 mm2

20. VARIOUS POSSIBLE GEOMETRIES
OF T-BEAMS
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Single Tee
Twin Tee
Box

21. EXAMPLE
 Determine the design strength of the T-beam
shown below. fy= 420 MPa, fc′= 35 MPa.
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22. EXAMPLE
 Determine the design strength of the T-beam
shown below. fy= 420 MPa, fc′= 28 MPa.
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23. APPENDIX
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24. 24

25. 25

26. 26