Engineering_Policy_Guide - User contributions [en]

Talk:237.8 Contract Time

2013-04-10T21:06:21Z

Dorend1: Request link to Road User Cost Request

It would be helpful to add a link to the road user cost request form to this page. It is difficult to find on the website and would be much easier to find if it were added to the contract time and/or standard forms pages.

http://wwwi/intranet/tp/programs_plans_reports/documents/Road%20User%20Costs%20Request%20Form.docx

Thanks!

Category talk:626 Rumble Strips

2013-01-30T19:36:14Z

Dorend1: New page: Is there a preferred location of where to begin/end the rumble strip for a ramp? Does it need to be placed on the acceleration or deceleration lane? We have seen locations where it stops...

Is there a preferred location of where to begin/end the rumble strip for a ramp? Does it need to be placed on the acceleration or deceleration lane? We have seen locations where it stops where the auxiliary lane is added, but does it make more sense to take it closer to the gore?

Thanks.

Talk:750.7 Non-Hydraulic Considerations

2010-09-22T15:11:12Z

Dorend1: /* 750.7.2.1 - Group C Pipe??? */ new section

'''750.7.8''' calls for Safety Slope End Sections on all drainage pipes greater than 21 in. that fall within the clear zone.

This seems overly conservative as the '''2006 Roadside Design Guide''' (RDG) 3.4.2.1 states "If a foreslope is traversable, the preferred treatment for any cross-drainage structure is to extend (or shorten) it to intercept the roadway embankment and to match the inlet or outlet slope to the foreslope. For small culverts, no other treatment is required." The RDG goes on to define a small pipe culvert as a single pipe up to 36" or a battery of pipes up to 30".

Why are we so much more conservative than the RDG?

--[[User:Martik2|Martik2]] 13:43, 23 March 2009 (CDT)

[[User:tschid|Dan Tschirgi]]: It appears that the current policy and the table on Standard Plan 732.10 are a "one size fits all" approach that applies to crossroad and parallel structures. This approach is outdated in the current approach of practical design. We will undertake some revisions to make the policy and standards consistent with the Roadside Design Guide. These revisions will be placed on the next available engineering policy ballot and if approved, could be effective by July 1. Please contact Joe Jones or me to provide additional comments for the revisions or to check on the status.

Thank-you for pointing out this inconsistency which will likely result in cost savings.

== 750.7.2.1 - Group C Pipe??? ==

This section mentions that "Group C pipe should be specified for the portion of median outlet pipes outside the edge of pavement where such pipes are located on high fills requiring a break in flowline grade. Details for such installations are illustrated in Pipe Grades For Median Drop Inlets."

The linked application figure shows Group B pipe and not Group C as mentioned in the text.

Category talk:616 Temporary Traffic Control (MUTCD Part 6)

2010-08-02T14:07:40Z

Dorend1: /* 40 mph taper lengths */ new section

The work zone figure entitled "a typical detour" shows signs numbered 17R, 18, 29 and 52 on sheet 1, but does not define what these signs are.
--[[User:Martik2|Martik2]] 15:57, 28 January 2009 (CST)

[[USER:smithk|Keith L. Smith:]] Sorry for the delay in answering you. These signs are identified in [http://epg.modot.org/files/1/1c/616_Sign_and_Device_Legend%2C_dec_22_08.pdf Fig. 616, Signs and Devices Legend]. "17R" is Detour (right), M04-1; "18" is Detour Ahead, WO20-2; "29" is Road Closed, R11-2 and "52" is End Detour, MO4-8a. Someday we will have the technology to improve on this method that relies on using a legend to decode the signs' numbers.

== 40 mph taper lengths ==

In the sign spacing and device spacing chart, the taper lengths for 40 and 45 mph are lumped together. The problem with lumping 40 with 45 is that the equation used to determine the taper length changes between 40 and 45 mph. This leads to a much greater difference in taper length than would normally be expected for a 5 mph difference. Although the equations are both shown in the chart, the people using the chart and not equations will be using a 540' taper when only a 320' is needed (12 ft lane). Adding another row to the table for 35-40 mph might be a solution to this issue.