Transportation Engineering — Quiz 1

Questions in this quiz (10)

1. A circular horizontal curve has a deflection angle of $$39^\circ$$ between two tangents and a radius of $$600$$ ft. What is the length of the curve?

   • $$378\text{ ft}$$
   • $$408\text{ ft}$$
   • $$466\text{ ft}$$
   • $$534\text{ ft}$$

2. A highway has a design speed of $$60$$ mph. Using a perception-reaction time of $$2.5$$ seconds and a deceleration rate of $$11.2$$ ft/s $$^2$$, calculate the minimum stopping sight distance.

   • $$346\text{ ft}$$
   • $$566\text{ ft}$$
   • $$607\text{ ft}$$
   • $$311\text{ ft}$$

3. Find the maximum flow rate of a highway if the speed is $$60$$ mph and the density for Level of Service B is used for optimum density.

   • $$800\text{ veh/hr}$$
   • $$1100\text{ veh/hr}$$
   • $$1200\text{ veh/hr}$$
   • $$1500\text{ veh/hr}$$

4. On a highway segment, the traffic density is measured as $$45$$ veh/mi and the space mean speed is $$55$$ mph. What is the traffic flow rate?

   • $$100\text{ veh/hr}$$
   • $$1238\text{ veh/hr}$$
   • $$3631\text{ veh/hr}$$
   • $$2475\text{ veh/hr}$$

5. The relationship of traffic flow can be written as $$q=kv$$, where $$q$$ is the traffic volume, $$k$$ is the traffic density, and $$v$$ is the average speed of vehicles. Based on observations, $$v$$ can be approximated by $$v=80-0.5k$$. Determine the traffic density if the average speed of vehicles is $$30$$ km/h.

   • $$70\text{ vehicles/km}$$
   • $$80\text{ vehicles/km}$$
   • $$90\text{ vehicles/km}$$
   • $$100\text{ vehicles/km}$$

6. A flexible pavement structure consists of $$4$$ inches of asphalt surface with layer coefficient $$0.44$$, $$8$$ inches of granular base with coefficient $$0.14$$, and $$12$$ inches of granular subbase with coefficient $$0.11$$. Calculate the structural number $$SN$$.

   • $$24.00$$
   • $$2.88$$
   • $$5.52$$
   • $$4.20$$

7. According to Greenshields linear speed-density model, free flow speed is $$70$$ mph and jam density is $$180$$ veh/mi. If density is $$60$$ veh/mi, find the space mean speed.

   • $$47mph$$
   • $$23mph$$
   • $$10mph$$
   • $$93mph$$

8. A highway exit ramp has $$5\%$$ superelevation. Design speed is $$40$$ mph. Side friction factor is $$0.18$$. What is the radius of the horizontal curve?

   • $$465ft$$
   • $$450ft$$
   • $$470ft$$
   • $$460ft$$

9. A highway section has grade $$1.5\%$$, design speed $$70$$ mph, reaction time $$2.0$$ seconds. Calculate stopping sight distance.

   • $$550ft$$
   • $$600ft$$
   • $$650ft$$
   • $$700ft$$

10. A circular horizontal curve has deflection angle $$39^\circ$$ and radius $$600$$ ft. Find curve length.

    • $$378ft$$
    • $$408ft$$
    • $$466ft$$
    • $$534ft$$