TT Txdot Problems Solutions
Transcript of TT Txdot Problems Solutions
-
7/29/2019 TT Txdot Problems Solutions
1/39
1
Test MastersTraffic / Transportation Engineering PE Exam
Depth Review
(Note: To work these problems in class you need to have the following manuals:AASHTO Green Book
Highway Capacity ManualLindeburg Reference Manual
Test Masters Notes)
Mark Ingram, PE (Texas)Associate Vice President
Principal Director Traffic Engineering
-
7/29/2019 TT Txdot Problems Solutions
2/39
2
1. A vertical curve with a negative 1.25% grade followed by a positive 3% grade has
a PVI station of 17+33 and an elevation at the PVI of 465 feet. The point of vertical
curvature station is 9+33.
a. The elevation of the PVC is most nearest: (ft)
Most Nearest (in feet)A) 460
B) 465
C) 475
D) 489
b. The elevation of the PVT is most nearest: (ft)
A) 460
B) 465
C) 475
D) 489
c. The elevation on the curve at station 17+33 is most nearest: (ft)
A) 460
B) 465
C) 473
D) 483
2. A signalized intersection has 3 eastbound lanes and 3 westbound lanes and one
left turn lane in each direction. The median width is 2 feet wide at the intersection.
All lanes are 11 feet wide. The intersection is located in a flat suburban area and has
pedestrian demands of 45 pedestrians per cycle northbound and 30 pedestrians per
cycle southbound. Compute the minimum green time for the north/south pedestrian
intervals (Gp). The crosswalk width is 12 feet and is clear of all obstructions. The
signal cycle length is 60 seconds.
Most Nearest (in seconds)
A) 20
B) 22
C) 24
D) 33
3. Assume the average spacing between front bumpers of successive vehicles is
approximately 30 feet; the best estimate for the jam density (vehicles per mile) in
one lane of a typical urban arterial street is most nearly:
A) 105
B) 115
C) 175
D) 280
-
7/29/2019 TT Txdot Problems Solutions
3/39
3
4. A segment of highway on a negative 3 percent grade (G = -3%) has been
experiencing high accident rates. It was concluded that the deceleration rate of the
average driver on this segment of highway is 9.0 ft/s2
and brake reaction times were
found to be 3.2 seconds. Studies have shown that in this segment of highway, thedriver eye height is 3.0 feet. The -3% grade is followed by a +2% grade on the
vertical alignment.
a. Assuming an object height of 24 inches, the stopping sight distance for the 60 mph
design speed is most nearest (ft):
A) 100
B) 480
C) 600
D) 760
b. Using the stopping sight distance found in part (a), determine the length of
vertical curve required for a 60 mph design speed.
A) 947
B) 955
C) 963
D) 1025
5. A 400 foot, vertical sag curve connects two tangents: a -2.5% downward (left to
right) tangent followed by a +2% upward (left to right) tangent. The tangents
intersect at the PVI which has a station of 926+25 and an elevation of 945.31 feet.
The width of the paved surface is 48 feet. The pavement has an average cross slope
of 1.6% from centerline (crown) of pavement to the gutter.
The station of the point of vertical curvature (PVC) is most nearly:
A) 928+25
B) 926+25
C) 924+25
D) 922+25
The station of the low point is most nearly:
A) 926+20
B) 926+37
C) 926+47
D) 930+00
The elevation of the low point is most nearly (ft):
A) 935.2
B) 947.5
C) 947.1
-
7/29/2019 TT Txdot Problems Solutions
4/39
4
D) 950.4
What is the elevation of a gutter drain inlet located at the side of the road at the
lowest point on the curve?
A) 947.9
B) 947.5
C) 947.1D) 947.4
6.
A six lane freeway with a measured speed of 63 mph passes through rolling terrain.
A few sections have grades greater than 3%, but none of these sections are longer
than mile. Each lane is 10 feet wide. The clear distance between overpass
abutments and roadside obstructions is 2 feet for both roadside and median edges.
A recent traffic study shows that the directional weekday peak hour volume is 2400
vph. 750 vehicles pass during the most congested 15 min peak hour period. The
weekday traffic stream consists of 14% trucks, 8% buses, and 4% RVs vehicles.
The roadway is both commuter and recreational.
a) The weekday heavy vehicle factor is most nearly:
A) .5
B) .6
C) .7
D) .8
b) The weekday LOS for this freeway is most nearly:
A) D
B) C
C) B
D) A
c) What would the volume to capacity ratio have to be in order to improve the level
of service to the next letter level.
A) .49
B) .54
C) .77
D) 1.0
7. The primary determinant for multilane highway level of service is:
A) Average Speed
B) Volume to Capacity (V/C)
C) Maximum service flow rate
D) Density
-
7/29/2019 TT Txdot Problems Solutions
5/39
5
8. What depth dimension should be given to a single vehicle parking slot in a
municipal parking area where the parking angle is set at 45 degrees. (feet)
A) 25
B) 22
C) 20
D) 18.5
9. The accident report of a highway patrol officer reads as follows:
I responded to a call regarding an accident at the intersection of Scenic Drive and
Main Street. When I arrived at the scene I observed a stationary truck that had just
skidded into a parked car. There were no injuries. The road was dry. The length of
skid from the truck was 180 feet. The truck was traveling south on Scenic Drive
which has a grade of -5.0%. I estimated the impact speed at approximately 20 mph
(based on the vehicular damage).
A study of the accident location later concluded that the following friction factorsapplied to this location for speeds prior to breaking:
20 mph; f=.46
30 mph; f=.38
40 mph; f=.32
50 mph; f=.30
60 mph; f=.28
The speed of the truck just prior to breaking was most nearly (ft/s)
A) 43
B) 48
C) 55
D) 63
10. The bearings of two tangents connected by a horizontal circular curve are
N50E and S35E respectively. The tangents intersect at station 37+00. The curve
radius is 800 feet. The station of the PT is most nearly:
A) 28+26.95
B) 37+00
C) 41+53.40
D) 45+73.05
-
7/29/2019 TT Txdot Problems Solutions
6/39
6
11. A four lane highway is to be constructed using a 6% superelevation on a 6
degree curve. The lane width is 12 feet, and normal crown is 1.5%. The bearing of
the back tangent is S30W and the bearing of the forward tangent is S60E. The
length along the curve (in feet) that is fully superelevated is most nearly: (50 mph
design speed):
A) 1500B) 1475
C) 1414
D) 1300
12. A traffic signal has been installed at the intersection of Main Street and First
Street. The green time for the east/west movement is 54 seconds and the green time
for the north/south movement is 59 seconds. The lost time and change & clearance
interval for the east / west movement are 3 seconds and 4 seconds respectively. The
lost time and change & clearance interval for the north/south movement are 4
seconds each. The cycle length is 120 seconds. The effective green time for the east /
west movement is: (seconds):A) 54
B) 61
C) 55
D) 59
13. A traffic signal approach has 23 seconds of green time with a yellow interval of 3
seconds and an all red interval of 2 seconds. A study determined that the lost time
along the approach is 4 seconds. The effective green is most nearly: (seconds)
A) 23
B) 24
C) 25
D) 26
14. At the intersection of Main Street and 3rd Street it has been determined that the
following conditions exist:
Start up lost time = 2 seconds
Extension of the effective green = 3 seconds
Yellow interval = 4 seconds
Red interval = 2 seconds
Green time = 32 seconds
Cycle = 60 seconds
The effective green is most nearly (seconds):A) 32
B) 33
C) 34
D) 35
-
7/29/2019 TT Txdot Problems Solutions
7/39
7
15. Given the following speeds along the eastbound segment of a five lane highway
with a design speed of 50 mph, determine the space mean speed (mph) for the
eastbound segment of highway. Speeds given: 57.6 mph, 62.4 mph, 62.1 mph, 74.4
mph, and 49.6 mph.
A) 88.26
B) 60.18C) 40.26
D) 50.18
16. Given the following freeway configuration, find the weaving segment level of
service.
Flow Rate (A C) = 4000 pcph
Flow Rate (B C) = 600 pcph
Flow Rate (A D) = 300 pcph
Flow Rate (B D) = 100 pcph
Weaving segment length = 1000
Free flow speed = 75 mph
Measured speed of the weaving vehicles (on average) = 50 mph
Measured speed of the non-weaving vehicles (on average) = 60 mph
A) E
B) D
C) C
D) B
-
7/29/2019 TT Txdot Problems Solutions
8/39
8
17. You have been asked to determine the operations along the crosswalk in the
central business district. The following information is gathered.
crosswalk width = 8 feet
Volumes were determined in 15 minute segments
o 5:00 5:15 = 1000 peds/15 min
o 5:15 5:30 = 1607 peds/15 mino 5:30 5:45 = 1608 peds/ 15 min
o 5:45 6:00 = 1520 peds/ 15 min
no other obstructions in the sidewalk
Find the following:
A) Find the level of service for the average flow condition:
A) E
B) D
C) C
D) B
B) Find the level of service for the platoon condition:
A) E
B) D
C) C
D) B
18. A new stop for an express bus route is planned along Main Street from the
suburb to the central business district. All buses used for this line are conventional
(rigid body) buses with one door for alighting and boarding. There are currently 5existing stops. The existing system (5 stops) has a total dwell time of 105 seconds.
The new stop will add 8 alighting passengers and 10 boarding passengers during the
peak operation. Current busses are on average 80% occupied and are rarely if ever
completely full. The line only operates on a prepaid quick boarding card system.
A) Determine the amount of additional dwell time (in seconds) added to the
system due to the addition of the new stop. Since this stop does not exist, use
conservatively high values for any assumptions (if needed) as outlined in the
2000 edition of the Highway Capacity Manual.
A) 21B) 31
C) 41
D) 51
-
7/29/2019 TT Txdot Problems Solutions
9/39
9
B) It has been concluded that the new stop will result in the on time percentage
to drop from 95% to 93%. From the users perspective how many late busses
will be encountered? This will be based on 5 round trips/week with notransfers. On time is defined as 0 to 5 minutes late departing the published
time point.
A) 1 late bus per month
B) 2 late buses per month
C) 1 late bus per week
D) 1 late bus per direction per week
19. Given the following volumes, determine the peak hour factor for the westbound
flow, just west of the intersection.
EB WB NB SB
LT TH RT LT TH RT LT TH RT LT TH RT
4:00 4:15 8 120 52 34 132 8 10 100 10 10 120 12
4:15 4:30 10 135 70 44 144 12 15 120 12 15 130 16
4:30 4:45 12 144 77 51 152 16 18 132 16 18 135 20
4:45 5:00 8 133 62 43 141 11 10 120 12 11 125 19
A) .91
B) .93
C) .95
D) .97
-
7/29/2019 TT Txdot Problems Solutions
10/39
10
20. A five mile four lane highway is to be constructed through a suburban area of
town. The highway will be built next year and is projected to carry 1200 vehicles
per hour on the weekday and 1400 vehicles per hour on the weekend. The lane
width is proposed to be 12 feet wide. The highway will consist of a 25 foot wide
grass median. The highway will have a 3 foot shoulder (left hand side) between the
edge of travelway and the median and a 10 foot shoulder (right hand side) betweenthe edge of travelway and the recoverable slope. The base free flow speed for the
multilane highway is 60 mph. There is an access management plan in place that will
limit the total number of access points onto the highway at a total of 60. The
highway will serve as a both a commuter and recreational highway from the
suburban area to the urban segment of highway 5 miles away.
% trucks are projected to be 2%
% busses are projected to be 10%
% recreational vehicles are projected to be 5%
A) The free flow speed for this multilane highway is most nearest:
A) 60
B) 57
C) 53
D) 50
B) The weekday passenger car equivalent flow rate is most nearly (pcphpl):
A) 600B) 717
C) 825
D) 1200
-
7/29/2019 TT Txdot Problems Solutions
11/39
-
7/29/2019 TT Txdot Problems Solutions
12/39
-
7/29/2019 TT Txdot Problems Solutions
13/39
-
7/29/2019 TT Txdot Problems Solutions
14/39
-
7/29/2019 TT Txdot Problems Solutions
15/39
-
7/29/2019 TT Txdot Problems Solutions
16/39
-
7/29/2019 TT Txdot Problems Solutions
17/39
-
7/29/2019 TT Txdot Problems Solutions
18/39
-
7/29/2019 TT Txdot Problems Solutions
19/39
-
7/29/2019 TT Txdot Problems Solutions
20/39
-
7/29/2019 TT Txdot Problems Solutions
21/39
-
7/29/2019 TT Txdot Problems Solutions
22/39
-
7/29/2019 TT Txdot Problems Solutions
23/39
-
7/29/2019 TT Txdot Problems Solutions
24/39
-
7/29/2019 TT Txdot Problems Solutions
25/39
-
7/29/2019 TT Txdot Problems Solutions
26/39
-
7/29/2019 TT Txdot Problems Solutions
27/39
-
7/29/2019 TT Txdot Problems Solutions
28/39
-
7/29/2019 TT Txdot Problems Solutions
29/39
-
7/29/2019 TT Txdot Problems Solutions
30/39
-
7/29/2019 TT Txdot Problems Solutions
31/39
-
7/29/2019 TT Txdot Problems Solutions
32/39
-
7/29/2019 TT Txdot Problems Solutions
33/39
-
7/29/2019 TT Txdot Problems Solutions
34/39
-
7/29/2019 TT Txdot Problems Solutions
35/39
-
7/29/2019 TT Txdot Problems Solutions
36/39
-
7/29/2019 TT Txdot Problems Solutions
37/39
-
7/29/2019 TT Txdot Problems Solutions
38/39
-
7/29/2019 TT Txdot Problems Solutions
39/39