00714801

Component

http://onlinepubs.trb.org...trr/1995/1489/1489-003.pdf

https://scholar.google.co...elig&publication_year=1995

The major causes contributing to railway subgrade problems are explained. Repeated dynamic loading, fine-grained soils, and excessive moisture content are indicated to be the major causes. The characteristics of different subgrade problems are discussed. Progressive shear failure, excessive plastic deformation, and subgrade attrition with mud pumping are the major problems for most railway subgrades under repeated traffic loading. The practical approaches for evaluation of subgrade are discussed. To identify potential problem subgrade sites, the recommended approaches include the use of the available soil, geologic, and hydrologic information; visual inspection; study of track maintenance history; and analysis of track geometry car measurements. To assess subgrade conditions for a site known to have track foundation problems, the recommended approaches include the field subsurface inspection, laboratory tests, cone penetration test, and track stiffness test. For each of these approaches its application to the railway subgrade is analyzed and discussed.

This paper appears in Transportation Research Record No. 1489, Railroad Transportation Research. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved

01495777

English

p. 17-25

1995

Transportation Research Record

0309061555

Figures (7) ; References (9) ; Tables (1)

Accelerated tests; Cone penetrometers; Failure; Fine grained soils; Geological surveying; Inspection; Laboratory tests; Losses; Moisture content; Mud pumps; Plastic deformation; Railroad tracks; Repeated loads; Soils; Subgrade (Pavements)

Track stiffness

Geotechnology; Highways; Railroads

TRIS, TRB

Nov 30 1995 12:00AM

• BALTIMORE-WASHINGTON CORRIDOR MAGNETIC LEVITATION FEASIBILITY STUDY
• DEVELOPMENT OF NONCONVENTIONAL TIE AND TRACK STRUCTURE INSPECTION SYSTEMS
• EVALUATION OF SELECTED CRASHWORTHINESS STRATEGIES FOR PASSENGER TRAINS
• INSULATING A PRECAST CONCRETE CROSSING WITH ELASTOMERIC RAIL ENCLOSURE
• MODELING SINGLE-LINE TRAIN OPERATIONS
• OPERATIONS AND SAFETY CONSIDERATIONS IN HIGH-SPEED PASSENGER/FREIGHT TRAIN CORRIDORS
• ORIGIN-TO-DESTINATION TRIP TIMES AND RELIABILITY OF RAIL FREIGHT SERVICES IN NORTH AMERICAN RAILROADS
• STRATEGIC ENVIRONMENTAL ASSESSMENT OF EUROPEAN HIGH-SPEED TRAIN NETWORK