01620153

Component

https://doi.org/10.3141/2607-04

Geogrids usually are used in railroad track substructure for ballast reinforcement and stabilization over a weak subgrade. Different aperture shapes affect the confining effect on ballast particles due to the unique interlocking mechanism. To understand the effect of aperture shape on ballast particle movement and the associated interlocking mechanism, three types of ballast box tests were conducted: one without geogrid as a control, one with a layer of biaxial geogrid, and one with a layer of multiaxial geogrid. If a geogrid was included, the geogrid was placed 30 cm below the top of the ballast. A half-section of a railroad track structure consisting of two crossties, a rail, ballast, subballast, and subgrade was constructed in a ballast box. Four wireless devices known as SmartRocks were embedded under the rail seat and under the shoulder at the ballast–subballast and subballast–subgrade interfaces. Results indicate that the multiaxial geogrid significantly decreased accumulated vertical displacement in the ballast surface under cyclic loading and has the best potential for confining particle movement. The advantages of having a layer of multiaxial geogrid, including reducing particle movement, as well as decreasing vertical displacement of the ballast surface, are discussed.

01631076

17-04365

English

pp 15–23

2017

Transportation Research Record: Journal of the Transportation Research Board

9780309441674

Print

Figures (10) ; Photos; References (22) ; Tables (2)

Ballast (Railroads); Dislocation (Geology); Geogrids; Railroad tracks; Repeated loads; Soil stabilization

Vertical displacement (Structures)

Geotechnology; Railroads

TRIS, TRB, ATRI

Dec 8 2016 11:40AM

• A Timetable Rescheduling Approach and Transition Phases for High-Speed Railway Traffic During Disruptions
• Assessing the Damaging Effects of Railway Dynamic Wheel Loads on Railway Foundations
• Deformation and Dynamic Load Amplification Trends at Railroad Bridge Approaches: Effects Caused by High-Speed Passenger Trains
• Finite Element Analysis of Rail-End Bolt Hole and Fillet Stress on Bolted Rail Joints
• Integration of Light Rail on the I-90 Floating Bridge Across Lake Washington
• Iterative Method for Predicting Uneven Settlement Caused by High-Speed Train Loads in Transition-Zone Subgrade
• Railway Ballast Permeability and Cleaning Considerations
• Real-Time Energy-Saving Optimization for Multiple Trains Based on Multiagent Cooperative Control
• Repeatable Procedure for Determining a Representative Average Rail Profile
• Track Support Measurements for Improved Resiliency of Railway Infrastructure