Test 2 Prep

Question 1

What are the 7 parts of a roundabout?

Answer 1

Central island, splitter island, circulatory roadway, apron, entrance line, accessible pedestrian crossings, landscape strip

Question 2

What is a central island?

Answer 2

A raised area in the center around which traffic circulates (not necessarily circular, can be traversable)

Question 3

Splitter island

Answer 3

Raised/painted area on approach used to separate entering/exiting traffic - Deflect to slow entering traffic, 2-stage pedestrian crossing

Question 4

Circulatory roadway

Answer 4

Curved path used by vehicle to travel counterclockwise around the central island

Question 5

Apron

Answer 5

Traversable portion of the central island adjacent to circulatory roadway needed for wheel tracking of large vehicles

Question 6

Entrance line

Answer 6

Point of entry into circulatory roadway- Extension of circulatory roadway edge line, functions as a yield

Question 7

Accessible pedestrian crossings

Answer 7

Crossing location typically set back from entrance line splitter island typically cut to allow pedestrians (including wheelchairs) to pass through

Question 8

Landscape strip

Answer 8

Separate vehicular and pedestrian traffic

Question 9

Difference between roundabouts, rotaries, and traffic circles

Answer 9

Rotaries are older, higher speeds on approaches, can require circulating traffic to yield to entering traffic

Question 10

How do costs differ from signalized intersections?

Answer 10

Roundabouts are not signalized, have lower life cycle costs, and promote increased fuel efficiency

Question 11

How do roundabouts accommodate pedestrians and cyclists?

Answer 11

Pedestrians are safer because of reduced speeds of entering vehicles, shortened ped. crossings, bicyclists can use crossings or ride through roundabouts

Question 12

How do roundabouts accommodate trucks?

Answer 12

Can be built to accommodate large turning radii of large trucks and trailers, can be safer and more efficient in emergency situations

Question 13

Downsides to roundabouts

Answer 13

Sometimes do not properly accommodate cyclists, issues with multilane circulating roadways

Question 14

Dutch solutions for roundabout issues

Answer 14

Cycle track around roundabouts, turbo-roundabouts

Question 15

What is a turbo-roundabout?

Answer 15

Multilane design, discourages lane changing on approach, cyclists and peds given priority, small circles and wide entrances force low speeds from motorists, single lane for entry and exit

Question 16

Curbside productivity index

Answer 16

Takes into account vehicle activity, occupancy size, and dwell time to provide relative utility of a given curb space

Question 17

Level of Traffic Stress

Answer 17

4 different ratings of comfortability of bike environments - most stressful aspect governs the chosen rating

Question 18

Risk exposure model

Answer 18

Number of incidents equals risk times exposure

Question 19

Risk

Answer 19

Probability of crash per exposure

Question 20

Exposure

Answer 20

Opportunity for interaction with hazard

Question 21

Vision Zero

Answer 21

Campaign to help communities to eliminate all traffic fatalities and severe injuries

Question 22

Traditional approach

Answer 22

Prevent crashes, improve human behavior, control speeding, individual responsibility, react based on crash history

Question 23

Safe systems approach

Answer 23

Prevent deaths and serious injuries, design for human error, reduce system kinetic energy, share responsibility, proactively identify and address risks

Question 24

Safe systems pyramid (bottom up)

Answer 24

Socioeconomic factors, built environment, latent safety measures, active measures, education

Question 25

Socioeconomic factors

Answer 25

Affordable housing near transit, zoning reform

Question 26

Built environment

Answer 26

Roundabouts, curb extensions, raised crosswalks, sidewalks, bikeways

Question 27

Latent safety measures

Answer 27

Signal timing, leading pedestrian intervals, air bags, automated emergency braking

Question 28

Active measures

Answer 28

Signals and signs, in-vehicle collision warnings, seat belts, helmets

Question 29

Education

Answer 29

Driver education programs, Slow Down campaigns