MUTCD Question for Transportation

[blondebedhead]

Shoulder work needs to be completed on a freeway. The 85th percentile speed is 65 MPH and the offset required is 18 ft. How far in advance of the first cone should a drive see the first "Right Side Shoulder Closed" sign?

A. 1000 ft.

B. 1500 ft.

C. 1890 ft.

D. 2890 ft.

Could someone please answer this question, I have the answer but it sort of falls under gray area in MUTCD as far as I am concerned.

Much obliged,

 

[ptatohed]

bbh,

The way I look at it, calculating the cone transition length, L, from the speed and offset is not necessary. Since sign spacing is measured from the first cone, we don't need to know L.

I went to 2009 MUTCD pg 632 Table 6H-1 to find the best Typical Application (TA) for this problem. It seems to be TA-5, Shoulder Closure on a Freeway, pg 643.

TA-5 shows three advanced warning signs a distance of 500’ from the first cone, a distance of ‘A’ from the first cone, and a distance of ‘A’ + ‘B’ from the first cone. Per TA-5, the first of the two Shoulder Closed signs starts a distance ‘A’ from the first cone. Per Table 6H-3, pg 633, A = 1,000’ for a freeway.

So I'd go with answer A.

 

[John QPE]

I need to look at this one again, I was in the completely wrong table. I haven't really gotten into the MUTCD yet, thanks for pointing out Table 6H-1 .. it will be tabbed wen I get home.

 

[blondebedhead]

Ptatohed,

TA-5 is correct Application,

Shouldn't the First Right Side Shoulder Closed sign from the cones be at 500' + A distance (1000' in this case from Table 6H-3). = 1500'.

The Answer you gave is correct as per my SofPE material but it still doesn't make sense.

 

[blondebedhead]

Never mind, just looked at 6H-5 again and got the answer 1000 ft. I shouldn't have added 500 ft. to "A" distance. 500 ft. is within 1000 ft.

I hope I don't make stupid mistakes like this on the exam in October!!!

Thanks for your help.

 

[John QPE]

Oh, A includes that 500 ft distance ... I just realized this. I was scratching my head on this one.

 

[ptatohed]

Oh, A includes that 500 ft distance ... I just realized this. I was scratching my head on this one.

Yup.

 

[John QPE]

I started getting into the MUTCD this weekend ... you can tell it is a gummint document .... it's so hard to comprehend a lot of the material in there.