State Aid-Bridge Frequently Asked Questions

AASHTO Drop Wall Requirements

What's the justification for drop walls on box culverts?

Culverts

Do you have any thoughts as to a way to note correct type of end section used for skewed box installations?
Any recommendations as to slab details for fill heights less than 1 foot?
Any ideas to clean up and ensure that a slab included on a proposed plan, covered by pay items or incidental to structure, is designed as required?

Riprap

Can a geotextile filter be used in lieu of the 6-12 inches of granular filter that we commonly call for under the riprap?

Blow Holes

I'm working on a project where we're looking at using a prestressed girder bridge; however, it's in a flood storage area, which submerges the bridge during the 100-year flood. I'm looking for guidance on using blow holes in the top of the deck to allow the air between the girders to escape, which will alleviate buoyancy and girder lateral loading problems. What do you think?

Watershed and DNR Dispute Resolution

Dispute resolution?

2000-2012 Minnesota Department of Transportation
395 John Ireland Blvd, St. Paul, MN 55155-1899
651-296-3000 Toll-free 800-657-3774 or 800-627-3529 (TTY, Voice, ASCII)

To request a MnDOT document in an alternative format, call 651-366-4718 or e-mail ADArequest.dot@state.mn.us

State Aid-Bridge FAQs

AASHTO Drop Wall Requirements