Perpendicular Beam Deflection question

AI Thread Summary
The discussion revolves around a structural engineering problem involving a W21x68 beam experiencing excessive deflection under a load of 1.388 kips per foot over a 34-foot span. To mitigate this issue, a W33x118 beam is proposed to be placed perpendicular to the W21, spanning 40 feet, with eight W21 beams resting on it at 4-foot-8-inch intervals. The goal is to limit the total deflection to a maximum of 1/4 inch. Clarifications are sought regarding the span length and positioning of the beams, as these factors significantly influence their relative stiffness and overall deflection. The problem is related to formwork for a concrete bridge, indicating its practical application in construction.
Bman426
Messages
2
Reaction score
0

Homework Statement


Given a W21x68 beam with 1.388 kips per foot loading spanning 34 feet. The beam will carry the load but the maximum deflection is greater than wanted. We would like to put a W33x118 beam perpendicular to the centerline of the W21x68 (17 feet), to limit the deflection.


Homework Equations


Calculating the the final deflection of the beams?


The Attempt at a Solution


?
 

Attachments

  • beams.jpg
    beams.jpg
    15.5 KB · Views: 580
Physics news on Phys.org
Is this a homework question or a work related question? What is the span length of the W33? Is the W21 resting at the mid span of the W33? The location affects the relative stiffnesses of the beams.
 
Sorry I didn't get back to post until now, I have been out of the area for a bit.

It is a work problem. The problem is one for a concrete bridge. This question comes from the formwork that is to be used to pour the new bridge. The contractor I am working with wants to limit the total deflection to 1/4 inch if possible. The W33 will span 40 feet and will have 8 of the W21x68 resting on it at 4' - 8" spacing.
 
This question is more appropriate for a forum such as http://www.eng-tips.com where similar problems are often discussed (I suggest)
 
Back
Top