Minimum Lane Width during construction. 1

[cgarlick]

We are looking to reconstruct a bridge over a turnpike and need to keep the local road open. However,the bridge is narrow and during construction the width of the open lane(signliazed control) might be less than 9'(which we have never done before). Does anyone know is MUTCD has a minimum requirement for this condition?

 

[cityeng]

I would be very carefull with how narrow you go. The outside wheel to outside wheel measurement for a school bus is 8-6. If you have no truck or bus traffic you have alot more flexibility. We had a similar situation for a 375' bridge replacement but were able to convince the city common council that closing the road to traffic was the best thing to do from a safety (both workers and residents), speed of construction, quality of work, and cost aspect. By closing the road during construction we were able to knock several months off of the construction time line and saved over$750,000.

 

[asdf]

You may be able to pick up another foot or so by knocking off the parapet and mounting railing to the fascia beam, if there..

 

[cgarlick]

Thanks for your replies. Just as a followup. We typically chip out the curb(1 foot) and put in steel g.r. in the median. It works pretty well. <br><br>The sad part is we would like to close the structure as it would be both time and cost effective but the detour for less than 400 cars a day was 4 miles. too far for most people.<br><br>Thanks for the information.

 

[ACtrafficengr]

A 4 mile detour isn't too bad, especially considering the low volumes. They will be delayed almost as long by the signal. In your next public meeting, tell the community it will take two years if you keep a lane open, or one with the detour.

Or, how about just detouring trucks?

In my NY State DOT days, we were redecking a bridge on a curve. The bridge designer said a 10' lane was plenty. The construction group said, no, it's on a curve, and the trucks will need more width because the back left wheel will off-track. They called us (Traffic Engr. & Safety) in to cast the deciding vote. I said get some flaggers out there, put cones where the barriers will be and see what happens.

Maintenance ran one of their snowplows through with no problem, but an interstate semi (19 m whgeelbase) came through and squashed a few cones. We put in a truck detour, but left the bridge open to passenger car traffic.

 

[jcfree]

The minimum widths in the U.S. are normally governed by AASHTO requirements. 9 feet is awfully narrow.