Question

6.20 A divided multilane highway in a recreational area has four lanes (two lanes in each direction) and is on rolling terrain. The highway has 10-ft lanes with a 6-ft right-side shoulder and a 3-ft left-side shoulder. The posted speed is 50 mi/h. Previously, there were 4 access points per mile, but recent development has increased the number of access points to 12 per mile. Before development, the peak-hour factor was 0.95 and the directional hourly volume was 2200 vehicles with 13% heavy vehicles. After development, the peak-hour directional flow is 2600 vehicles with the same vehicle percentages and peak-hour factor. What is the level of service before and after the development

Answer 1

Answer:

A) Level D ( before development )

B) Level E ( After development )

Explanation:

A) Calculate the level of service before the development

First we calculate the base free flow speed ( BFFS )

= posted speed limit  + 5 mi/hr.

= 50 + 5 = 55mi/hr.

Next determine free flow speed ( FFS )

= BFFS - $f_{lw} - f_{lc} - f_{m} - f_{A}$

= 55 - 6.6 - 0.65 - 0 - 2.25 = 45 mi/hr.

The remaining part of the solution is attached below

The level of service = D

given that:

Vp = 1537.096 pc/hr/In

Density = 34.157 pc/mi/In

FFS = 45 mi/hr

B ) Calculate the level of service after the development

attached below is the detailed solution

The level of service = E

given that

Vp = 1816.568 pc/hr/In

Density = 40.368 pc/mi/In

FFS = 45 mi/hr