Transportation Engineering — Quiz 2

Questions in this quiz (10)

1. Given a parabolic vertical curve with VPC station $$14+44$$ at elevation $$792$$ $$ft$$, an entry grade of $$+2\%$$, an exit grade of $$-3\%$$, and length of $$600$$ $$ft$$, the elevation of the point of vertical tangency is most nearly:

   • $$567\ \mathrm{ft}$$
   • $$789\ \mathrm{ft}$$
   • $$889\ \mathrm{ft}$$
   • $$897\ \mathrm{ft}$$

2. A $$600\ \mathrm{ft}$$ long equal-tangent crest vertical curve connects grades of $$+4.0\%$$ and $$-2.5\%$$. The point of vertical intersection (PVI) is located at station $$123+00$$ with an elevation of $$62.80\ \mathrm{ft}$$. What is the elevation of the PVT?

   • $$45.70\ \mathrm{ft}$$
   • $$47.60\ \mathrm{ft}$$
   • $$52.65\ \mathrm{ft}$$
   • $$55.30\ \mathrm{ft}$$

3. A horizontal circular curve has an intersection angle of $$16^\circ$$. The length of middle ordinate $$M$$ is $$8.00\ \mathrm{ft}$$. The radius of the curve is most nearly:

   • $$625.8\ \mathrm{ft}$$
   • $$752.6\ \mathrm{ft}$$
   • $$824.7\ \mathrm{ft}$$
   • $$889.7\ \mathrm{ft}$$

4. A $$800\ \mathrm{ft}$$ symmetric vertical curve is provided for a highway crest vertical curve. The grade of the back tangent is $$+2\%$$ and the grade of the forward tangent is $$-2\%$$. The elevation of the point of vertical intersection (PVI) is $$1200.00\ \mathrm{ft}$$. What is the elevation of the point of vertical curve (PVC)?

   • $$1192\ \mathrm{ft}$$
   • $$1208\ \mathrm{ft}$$
   • $$1184\ \mathrm{ft}$$
   • $$1216\ \mathrm{ft}$$

5. A $$6^\circ$$ curve has forward and back tangents intersecting at station $$14+87.33$$. The intersection angle is $$11^\circ21'35''$$. The station of BC is most nearly:

   • sta $$5+32.4$$
   • sta $$9+92.6$$
   • sta $$11+27.9$$
   • sta $$13+92.4$$

6. A vertical curve has $$L=8$$ stations and PVI at $$87+00$$. Grades are $$-2.0\%$$ to $$+1.6\%$$. The low point station is:

   • sta $$78+55$$
   • sta $$87+00$$
   • sta $$87+44$$
   • sta $$91+00$$

7. Using Greenshields model, if jam density is $$150\ veh/mi$$, density at capacity is:

   • $$15 veh/mi$$
   • $$45 veh/mi$$
   • $$75 veh/mi$$
   • $$230 veh/mi$$

8. A curve has $$R=600\ ft$$ and $$I=18^\circ$$. External distance $$E$$ is:

   • $$7.48$$
   • $$8.47$$
   • $$4.78$$
   • $$7.84$$

9. A four-phase signal has startup lost time $$2s$$, yellow $$4s$$, all-red $$1.5s$$, extension $$2s$$. Total lost time:

   • $$8 s$$
   • $$16 s$$
   • $$22 s$$
   • $$20 s$$

10. A horizontal curve has its PC at station $$32+50.00$$ and a curve length of $$425\ \mathrm{ft}$$. What is the station of the PT?

    • $$28+25.00$$
    • $$36+75.00$$
    • $$41+00.00$$
    • $$32+50.00$$