Transcript Slide 1

FINAL REPORT
TCRP Project D-14 [Report 155]
Track Design Handbook for
Light Rail Transit
2nd Edition
1
Prepared by:
Lawrence G. Lovejoy, P.E.
TCRP Report 57
Updating Required
Over a decade since
original publication
Doesn’t reflect other
TCRP research since then
Streetcar issues not
covered
Construction &
Maintenance not covered
in a comprehensive way.
•
•
•
•
2
The D-14 Project
Research Team
Parsons
Brinckerhoff
Wilson Ihrig &
Associates
Metro Tech
Consulting
Track Guy
Consultants
3
Report
57
4
Changes From Report 57
Chapter 1 – GENERAL INTRODUCTION
• Increased focus on who the Handbook user is
and how he/she fits within an LRT project.
• Expansion of the definition of what LRT is.
Chapter 2 – LIGHT RAIL TRANSIT VEHICLES
• Updated discussions about characteristics of
contemporary LRVs and Streetcars
• Added and in-depth discussion of how to
select an appropriate wheel profile.
5
Changes From Report 57
Chapter 3 – LRT TRACK GEOMETRY
• New discussion provided explaining the
relationships between lateral acceleration,
unbalance and the jerk rate
• Expanded discussion concerning track crosslevel
and limitations on twist in tangent track.
• Expanded discussion of alignment of freight
tracks and shared LRT/Freight tracks.
• New article on issues where LRT shares a
corridor (but not tracks) with a freight carrier
6
Changes From Report 57
Chapter 4 – TRACK STRUCTURE DESIGN
• The entire discussion about Nytram plots,
Filkins-Wharton diagrams and related issues
restructured to introduce basic concepts and
background information first and only then
develop the explanation of the methodology.
• Discussions about restraining rails and their
application has been greatly restructured and
expanded with reference to TCRP D-7 project.
7
Changes From Report 57
Chapter 5 – TRACK COMPONENTS & MATERIALS
• Tee rail discussion revised.
• Groove rail discussion completely rewritten.
• Restraining rail discussion completely rewritten.
• Rail Fastener / Rail Fastening discussion
relocated and rewritten
• Crosstie discussion largely rewritten
8
Changes From Report 57
Chapter 6 – SPECIAL TRACKWORK
• Expanded discussion on types of frogs including
flangebearing and jump frog designs.
• Revised/expanded discussion on selection of
turnout size.
• Revised and expanded discussion on switches,
including those for embedded track.
9
Changes From Report 57
Chapter 7 – STRUCTURES & BRIDGES
• Rewrote discussions of various types of
LRT structures and how they work.
• Entirely new discussion on structures
carrying embedded track.
• Entirely new discussion on open deck
structures and retrofitting existing
highway bridges to carry LRT track.
10
Changes From Report 57
Chapter 8 – CORROSION CONTROL
•
Miscellaneous revisions emphasizing interdisciplinary coordination issues.
Chapter 9 NOISE & VIBRATION CONTROL
•
.
Greatly expanded with extensive text revisions
addressing salient issues including wheel/rail
contact mechanics. Extensive new graphics
11
Changes From Report 57
Chapter 10 – TRANSIT SIGNAL WORK
•
•
New text on embedded switch machines.
Expanded text on rail bonding for signal and
power current, including reference to TCRP
D-7 work
Chapter 11 – TRANSIT TRACTION POWER
• Expanded discussion on how track alignment
affects OCS design.
12
New Chapters for 2nd Edition
Chapter 12 – LRT TRACK IN MIXED TRAFFIC
• Entirely new chapter with emphasis on track
alignment for streetcar style operations.
Chapter 13 – LRT TRACK CONSTRUCTION
•
Entirely new chapter with emphasis on how
LRT tracks of all types are actually built.
Chapter 14 – LRT TRACK MAINTENANCE
• Entirely new chapter with emphasis on how
LRT track maintenance is typically organized
and how it can be directly affected by
design decisions.
13
Changes From Report 57
Reversed Metric vs. US Traditional Measurement Units
• Report 57 was prepared under the old Metrification
Policy.
• Second Edition reverses the priority of SI vs. US
Traditional units of measurement
• US units now first, with SI units [in brackets]
EXCEPTION:
• When the dimension being discussed is metric in
origin (principally for manufactured products) the
SI units are listed first followed by a soft
translation to US Traditional Units.
14
Challenges that Remain
#1:
How can we keep the
Track Design Handbook
for Light Rail Transit
up-to-date?
15
For questions concerning this presentation
or for further information / assistance
contact:
Lawrence G. Lovejoy, P.E.
Senior Supervising Engineer / Professional
Associate
Parsons Brinckerhoff
Four Gateway Center, Suite 1305
Pittsburgh, PA 15222-1220
USA
Direct line: 1-412-644-3050
Cel phone: 1-412-580-1414
e-mail: [email protected]
http://www.pbworld.com/
16