INTRODUCTION TO
INFRASTRUCTURE:
AN INTRODUCTION TO CIVIL AND
ENVIRONMENTAL ENGINEERING
Chapter 4: Transportation Infrastructure
Overview

Roads

Mass Transit

Waterways

Tunnels

ASCE Grades
Roads
Roads: Categories
Roads: Street Design

Crowning
 Streets
are constructed with a side slope, usually 2% (2
inches per 100 inches).
 Prevents accumulation of water and Ice
Roads: Street Design

Cross Section
A
vertical “slice” of the street
Roads: Street Design

Vertical alignment
 Side-view
or profile view of the road.
Roads: Street Design

Horizontal alignment
 Plan
view of the road
Roads: Construction

Material
 Asphalt
vs. Concrete
 Granular Subgrade

Curves
 Must
not be too tight
for vehicle speed
Roads: Intersections

Design depends on vehicles
 Intersections
 Interchanges
 Roundabouts
Roads: Intersections

Conflict Points
 Vehicle
paths diverge, merge, or cross
 Typical intersection has 32
Mass Transit
Mass Transit

Includes buses, trolleys, ferries, and rail

Only 5% of Americans use mass transit

Decrease in ridership decreases revenue

Decrease in revenue creates problems in sustaining
the systems
Mass Transit: Rail

3 types of transit rail
 Light
Rail
 Low
speed street cars and trams (Houston Metro)
 Heavy
Rail
 Higher
speed, higher volume (NY Subway)
 Commuter
 High
Rail
speed, high volume rail between adjacent cities.
Rail: Shanghai Maglev Train
Rail: Shanghai Maglev Train

Background

China experienced rapid economic growth in the 21st century

Greater demand for high speed passenger transportation
resulted.

1999- Discussion of the feasibility of a Shanghai high speed rail
began

Advantages like no contact, high speed, low energy consumption,
and less environmental impact led to the approval of the project.

Train carries 574 and travels up to 505 km/hr
Rail: Shanghai Maglev Train




Maglev: Electromagnetic levitation
Electromagnetic field generated
through the excitation of on board
magnets and guideway magnets.
Magnets then attract each other,
pulling the train upward.
Levitation gap stability controlled
by current.
Rail: Shanghai Maglev Train

Suspension:

Approx. 15mm (.59in)

Magnetic attraction varies
inversely with the cube of
the distance between the
magnets.

Slight variations in distance
will cause dramatic force
changes.

How do we fix it?

Closely monitoring and
constantly adjusting the
current
Waterways
Waterways





Waterways include rivers, channels, ports, locks, etc…
12% of domestic and 80% of international goods are transported
using waterways
Rivers like the Mississippi, Ohio, and Missouri are called “Working
Rivers”
30,000 miles of navigable waterways
Controlling flows and dredging bottom sediment keep channels open
at necessary water depth.
Waterways: Ports

Allows for Intermodal transfer of
goods



Approx 150 ports in the U.S.


Standardized containers used
e.g. barge to rail or truck
3 of which rank in the top 20
worldwide busiest ports
China has more of the largest and
busiest ports than any other
country.
Waterways: Locks



Permit ship travel around
a dam or through a
shallow stretch
Gates open or close to
control flow and
consequently raise or
lower a ship
Approx 250 locks in the
US. (29 in the Mississippi
alone)
Tunnels
Tunnels

Very costly, but very effective.

Used primarily for rail and roadway transportation

Other uses
 Water
supply conveyance
 Hydroelectric power
 Utilities
 Water storage
Tunnels: The Channel Tunnel




AKA “Chunnel”
Runs between Britain
and France
Declared one of the 7
Wonders of the
Modern World by
ASCE
30 miles long, 250
feet below sea level
Tunnels: Twin Tunnels



Located in Shanghai, China,
under the Yangtze River.
Holds 3 lanes of traffic and one
lane of rail
Used the world’s largest tunnel
boring machine (50ft diameter)
ASCE Grades



ASCE- American Society of Civil Engineers
The ASCE gives a report card for the infrastructure of the
US
Most recent grades range from D- to C+





Roads: DMass Transit: D
Waterways: DRail: C-
Why are these grades so low?