Chapter 15, Problem 1P

To determine

(a)

Suitable design speed for the rural collector highway.

Answer to Problem 1P

$\text{30 mi/h}$

Explanation of Solution

Given information:

In mountains terrain is designed to carry volume of $\text{800 veh/day}$.

  

For a rural collector highway located in mountains terrain is designed to carry a design volume $\text{800 veh/day}$ is given Table $15.1$ from the textbook.

From the table the design speed for $\text{800 veh/day}$ is $\text{30 mi/h}$.

To determine

(b)

Lane and usable shoulder lengths for the rural collector highway.

Answer to Problem 1P

Lane= $12ft$

Shoulder = $5ft.$

Explanation of Solution

Given information:

In mountains terrain is designed to carry volume of $\text{800 veh/day}$.

For a rural collector highway located in mountains terrain is designed to carry a design volume $\text{800 veh/day}$ is given figure $15.5$ from the textbook.

  

From the figure $15.5$ the width of lane is $12ft$.

Width of shoulder is total $\text{10 ft}$ on each side of road is $5ft.$

To determine

(c)

Maximum desirable grade for the rural collector highway.

Answer to Problem 1P

Maximum desirable grade= $10\%$

Explanation of Solution

Given information:

In mountains terrain is designed to carry volume of $\text{800 veh/day}$.

  

From the Table $15.3(a-e)$ the maximum desirable grade for design speed is $10\%$.