concrete box culvert design

[Daplace]

I am designing concrete box culvert 12.00m by 6.00m, with 0.50m thickness and 0.05m wearing coat thickness. I used manual method by considering Kleinlogel formulas,and ROBOT. The manual method bending moment given by Kleinlogel formulas are very different from those found by ROBOT. I need a help to understand this difference.

 

[JedClampett]

You need to give us more information. Loads, assumptions, results, etc. In general Kleinlogel formulas should match computer analysis, within a margin. Node sizes, relative fixity, etc. can make a difference. But the results should be recognizable.
And I've never heard of ROBOT, but I'm still using a slide rule.

 

[johnbridge231]

You can also use any commercial (or non) for cross sectional analysis, as this is the most difficult part in your case. Then, the stability effects of the member can be checked easier.

Analysis and Design of arbitrary cross sections
Reinforcement design to all major codes
Moment Curvature analysis

http://www.engissol.com/cross-section-analysis-design.html

 

[IDS]

I haven't heard of Kleinlogel formulas, but assuming they are a way of analysing frames thay should give about the same results as a computer analysis for the same input loads and member dimensions and properties. I'd suggest using a 3rd analysis method to check which of the first two (if either) are correct.

I'd say the most difficult part was assessing the loads on the structure. 12x6 m is a large culvert and you need to be sure the design loads are appropriate.



Doug Jenkins
Interactive Design Services

http://newtonexcelbach.wordpress.com/