INTERSECTION AND DESIGN CONTROL

Question 1

play an important role in any network system. They are the points where
traffic flow converges and where direction of travel changes.

Answer 1

INTERSECTIONS

Question 2

This refers to the configuration of the intersection and would depend largely on the number of legs.

Answer 2

SHAPES

Question 3

Some of the most commonly observed intersection configuration is the following:

Answer 3

a. Three-leg T or Y
b. Four-leg: normal crossing, oblique, or skewed/staggered
c. Multileg: intersections with more than four legs

Question 4

The maximum number of legs should be _______

Answer 4

four

Question 5

Roads should not intersect at a small angle. Oblique intersections pose potential hazards
and cause high severity of accidents due to the almost head-to-head collision of vehicles. An angle of ______ degrees must be considered as the minimum

Answer 5

60

Question 6

For turning movements, a number of turning geometries may be considered, the
most direct of which is highly preferred. Configurations of turning geometries are:

Answer 6

• direct
• semidirect
• indirect

Question 7

These types of turning movements may be found as elements of the interchanges:

Answer 7

Trumpet
Cloverleaf

Question 8

Design elements of an intersection approach

Answer 8

1. Left turn storage bay
2. Through lanes
3. Exclusive right turn lane
4. Corner island
5. Turning roadway
6. Median
7. Nose Treatment

Question 9

Depending on the traffic volume using the intersection and the severity of conflicts,
intersection control may fall under any of the following categories:

Answer 9

a. Unsignalized
b. Signalized
c. Grade separation

Question 10

This is another form of unsignalized intersection that works best when the number of turning vehicles is almost equal to the number of through vehicles

Answer 10

Roundabout or Rotary

Question 11

all vehicles move counter clockwise in one-way fashion

Answer 11

roundabout

Question 12

has been implemented at several intersections within Metro Manila
for a number of years now.

Answer 12

U-turn Slots/ U-turn scheme

Question 13

is very similar to that of a roundabout
except that it favors a particular road, which is assumed to be the major road.

Answer 13

U-turn slots

Question 14

eliminates the problematic crossing conflicts of the different movements of vehicles.

Answer 14

Grade Separation

Question 15

to describe the minimum gaps needed by drivers of minor road vehicles

Answer 15

critical gap

Question 16

The source of capacity of the minor road flows is the available _____ between major road flows

Answer 16

gaps

Question 17

_____ on the minor road approach are lanes in which two or more movements are confine in the same lane

Answer 17

Shared lanes

Question 18

The difference between the existing flow and capacity is termed as ______

Answer 18

reserve capacity

Question 19

work best when there is not much fluctuation in traffic flow.

Answer 19

Pre-time or fixed time signals

Question 20

A particular intersection may be considered ______ if arrivals of vehicles at its approach
are random

Answer 20

isolated

Question 21

For isolated intersections where randomness of arrivals is expected

Answer 21

Traffic-actuated

Question 22

In planning for phase pattern and for the determination of appropriate timing of the
signals, a number of data are required:

Answer 22

Traffic Volume
Pedestrian FLows
Passenger car unit values (PCU)
Saturation flow rates
Physical characteristics of the road

Question 23

is a process by which right of way is given to particular movements in a logical
manner with the primary purpose of minimizing the number of conflicts.

Answer 23

phasing

Question 24

is one complete indication of green, yellow and red. Its length is constant for a
pre-time or fixed time signal. It varies for traffic-actuated signals depending on traffic demand.

Answer 24

cycle