G-01 (Flexural Design of Concrete Beams) |
  
|
G-01 (Flexural Design of Concrete Beams) |
|
Objective
To verify the design of the rectangular and Tee concrete beams
Problem Description
The following concrete beams are to be designed according to ACI 318-02 code. The flange width and thickness are given in parenthesis for Tee beams.
Beam |
B x H [Bf x Tf] (in) |
fc (ksi) |
fy (ksi) |
dt (in) |
d’ (in) |
Mu (ft-kips) |
1 |
10 x 16 |
4 |
60 |
13.5 |
2.5 |
123.2 |
2 |
14 x 23 |
4 |
60 |
20.5 |
2.5 |
516 |
3 |
10 x 21.5 [30 x 2.5] |
4 |
60 |
19.0 |
2.5 |
227 |
4 |
10 x 21.5 [30 x 2.5] |
4 |
60 |
19.0 |
2.5 |
400 |
5 |
10 x 22.5 |
3 |
40 |
20.0 |
2.5 |
129 |
6 |
11 x 25 |
3 |
60 |
22.5 |
2.5 |
403 |
7 |
10 x 20 |
4 |
60 |
16.0 |
2.5 |
211 |
Finite Element Model
7 beam elements with appropriate material and design criteria assigned
Model type: 2D Frame
Results
The design results of these beams are compared with the references.
Beam |
ENERCALC 3D |
References |
||||
As |
As’ |
As |
As’ |
Reference |
Page |
|
1 |
2.41 |
0 |
2.40 |
0 |
Ref [1] |
pp. 7-23 |
2 |
6.59 |
1.44 |
6.58 |
1.43 |
Ref [1] |
pp. 6-30 |
3 |
2.77 |
0 |
2.77 |
0 |
Ref [1] |
pp. 7-33 |
4 |
5.10 |
0 |
5.10 |
0 |
Ref [1] |
pp. 7-35 |
5 |
2.37 |
0 |
2.37 |
0 |
Ref [2] |
pp. 133 |
6 |
4.66 |
1.31 |
4.74 |
1.20 |
Ref [2] |
pp. 191 |
7 |
3.48 |
0.70 |
3.48 |
0.70 |
Ref [3] |
pp. 102 |
Comments
The results given by ENERCALC 3D are very close to the referenced values. The model consists of multiple simply supported beams. Nodal moments of opposite signs are applied to nodes to achieve uniform moments in each member. The program is very versatile to design multiple isolated beams as well as to design members in integrated frames.
Reference
[1]. “Notes on ACI 318-02 Building Code Requirements for Structural Concrete”, 8th Edition, Portland Cement Association, 2002
[2]. James G. MacGregor & James K. Wight, “Reinforced Concrete – Mechanics and Design”, 4th Edition, Pearson Prentice Hall, 2005
[3]. Arthur H. Nilson, David Darwin, Charles W. Dolan, “Design of Concrete Structures”, 13th Edition, McGraw-Hill Higher Education, 2004
