Perpendicular Beam Deflection question

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Bman426
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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
  • Structural diagram of a W21x68 beam spanning between two supports, with a uniform load of 1.388k/' shown as downward arrows; a W33x118 beam crosses perpendicular at midspan, with 17' to support labeled on each side.
    beams.jpg
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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.