Figure 11-22.—Compound curve.
QUESTIONS
Q1. Using the data given for the compound curve
shown in figure 11-22, compute the stations at
PC1, PI1, PCC (point of compound curvature),
PI2, and PT2.
Q2. Referring again to figure 11-22, assume that you
are tasked to stakeout the compound curve using
full stations. What deflection angles (d1, d2, and
d) and chord lengths (C1, C2, and C) will you use
for the 12° curve?
Q3. Assume that you are to set half stations for a
400-foot symmetrical vertical curve. The tan-
gents (g1 = + 3.2 percent, g2 = –1.6 percent)
intersect at Station 14 + 00. The tangent eleva-
tion at the PVI is 131.20 feet. Compute the fol-
lowing information for this curve:
a. Elevation at the PVC
b. Elevation at the PVT
c .
d.
Grade elevation on the curve at the PVI
Grade elevation on the curve at station
13 + 50
Station number and grade elevation on the
e.
curve at the turning point
Q4. Assume that you are to set half stations for a
600-foot vertical curve. The tangents (g1 = –3
percent, g2 = –8 percent) intersect at Station
15 + 00, which has an elevation of 640 feet above
mean sea level. You may also assume that
l1 = 400 feet and l2 = 200 feet. Compute the
following information for this curve:
a. Elevation at the PVC
b. Elevation at the PVT
c. Grade elevation on the curve at the PVI
d. Grade elevation on the curve at station
13 + 50
e. Station number and grade elevation on the
curve at the turning point
11-21
