Ted Sussmann

U.S. Department of Transportation · Structures and Dynamics Division

Review of current artificial intelligence and machine learning focused research and development of some conceptual areas where developments could support improved inspection activities including providing data on track condition following maintenance. The presentations reviews current data available to base new algorithms on and the use of emerging...

Presentation at the 2024 Annual Transportation Test Center Conference discussing track related research conducted at the center along with opportunities for future research. Both existing research technology and goal are discussed to highlight opportunities for the Pueblo, CO Transportation Test Center to continue help the U.S. Rail Industry advanc...

Strain gauges are often used to measure vertical wheel loads in a railroad track. This approach is based on the concept of differential-shear-strain (DSS) measurement: The difference in vertical shear force between two points along a beam equals the magnitude of the resultant of applied vertical forces in between. With a slight modification to the...

Under tie pads (UTPs) and under ballast mats (UBMs) are used in rail track construction to reduce track stiffness and increase the size of the ballast contact area where it meets track support elements either above the ballast (ties) or below the ballast (e.g., subgrade, bridge deck, or tunnel invert). Limited information on the in-track performanc...

Current railway track safety assessments are based primarily on track geometry data along with assessment of critical risk factors including rail profile and internal rail defects. Data supporting assessment of track safety and stability include 1) roadbed condition data such as ballast fouling from ground penetrating radar (GPR), 2) the support of...

This paper describes the Seismic Ballast Inspection Tool (SeiBIT), which was used to estimate the small strain shear wave velocity and shear modulus for comparison with estimates of Young’s modulus of railroad ballast from two long-term monitoring sites near Lincoln, Nebraska. One site consists of highly fouled ballast, while the second site consis...

Ballast plays an essential role in the response of a railroad track to repeated loading. Ballast degradation may lead to poor drainage, lateral instability, and excessive settlement. Extreme levels of ballast degradation may cause service interruptions and safety concerns. Therefore, ballast condition evaluation is of great importance in ensuring s...

Ballast degradation in the track substructure may cause poor drainage, settlement, and reduced lateral stability that may affect safety, daily operations, and long-term maintenance of a railroad system. Extreme levels of degradation in the ballast may result in service interruptions because of safety concerns. Therefore, field ballast condition eva...

Track structural inspection is a critical element supporting advances in rail safety. As rail safety has im-proved in the U.S., detection and diagnosis of critical contributors to the remaining track caused derailments has become increasingly more challenging. While failures that lead to derailments often have multiple con-tributing factors, safety...

The support of railway track is a critical requirement to achieve the potential of ballasted railway track to serve as one of the most cost-effective, safe, and reliable types of freight infrastructure. Uniform resilient support provided to the track structure (rails and ties) is generally needed to maintain stresses in the track structure that res...

The Transportation Technology Center, Inc. (TTCI) is working to build on and extend existing mechanics-based track geometry deterioration forecasting models to support improved safety and reliability of ballasted tracks. This paper demonstrates how the railway track lifecycle model (RTLM) ballast model performs against field data and makes recommen...

Workshop on International Perspectives to Reduce Track Caused Derailments

This manuscript presents findings from an ongoing research study at Oklahoma State University studying different factors that affect vertical tie reaction forces in ballasted railroad tracks. A combined approach involving field instrumentation and numerical modeling has been adopted for this purpose. Measurements of tie reactions can indicate the l...

Track Support Condition Assessment, Ballast Condition Assessment, and Demonstration of near real-time portal

Current regulations require locations of noncompliant ballast to be remediated within 30 days or to be taken out of service, regardless of track class. In 2013, the Association of American Railroads (AAR) applied for a waiver to the current regulations that proposed a track class specific approach to managing noncompliant ballast. In 2015, the Fede...

A majority of railway fixed infrastructure consists of subgrade and fill sections constructed from local materials well before the advent of modern geotechnical engineering and compaction technology. In the ensuing century or more following construction, weather extremes highlighted weak zones for reconstruction following floods, washouts, and soil...

Monitoring of linear infrastructure including roads, railroads, and pipelines is a critical element of ensuring resilience against emerging challenges such as climate change driven severe precipitation events. In this presentation, several questions and opportunities for basic research and studies that could support logical advancement of this tech...

The routine measurement of railway track functional condition including track geometry is common across the industry including the use of autonomous systems. Trending track geometry data to develop deterioration curves has highlighted the challenges with forecasting railway track condition. The central challenge in forecasting functional condition...

In 2013, the Association of American Railroads applied for a waiver to the current regulations that propose a track class specific approach to managing non-compliant ballast. In 2015, the Federal Railroad Administration granted the waiver subject to certain conditions including weekly track geometry measurements. Burlington Northern Santa Fe Railwa...

Current regulations require locations of non-compliant ballast to be remediated within 30 days or to be taken out of service, regardless of track class. In 2013, the Association of American Railroads applied for a waiver to the current regulations that proposed a track class specific approach to managing non-compliant ballast. In 2015, the Federal...

Application of track design concepts to the assessment of the impact of changes in track structure conditions or operations on track life and deterioration. Hay Lecture: https://railtec.illinois.edu/events/hay-seminar/

According to Hay [1], the support of railway track is a critical requirement to achieve the potential of railway track to serve as one of the most cost-effective types of infrastructure in terms of long-term maintenance cost. Uniform resilient support provided to the track structure (rails and ties) is needed to maintain stresses in the track struc...

Introductory Presentation to Pre-Conference Course laying out a few of the topics to be discussed during the day long course.

Gage Restraint Measurement System (GRMS) is focused on testing the gage strength of track against the limiting loaded gage of 59 in. for wheel drop derailment. Recent failures including rail seat abrasion, tie failure, state of good repair assessment, and spike failures provide opportunities to optimize GRMS loads for testing and inspection.

The ballast layer is intended to provide stable and resilient support to the track superstructure so that applied loads are reacted in an economically sustainable manner. The ballast layer must possess inherent strength to avoid failure under the intense loading of freight trains while providing adequate resilience to distribute loads along the tra...

Review of track geometry and gage widening under the gage restraint measurement system (GRMS) to assess conditions where track geometry and GRMS anomalies occur at track locations separately and together. GRMS anomalies tend to represent track structure locations where the rail-tie-fastener structure is degraded as compared to track geometry locati...

Track support is a basic necessity for reliable and cost effective railroad track infrastructure. Poor track support conditions lead to increased loading on track superstructure components and can accelerate deterioration of overall track condition. A variety of problems develop due to poor track support including increased tie load, rail stress, a...

Presentation

The use of ground penetrating radar (GPR) as a tool for track substructure inspection has increased in recent years. Transportation Technology Center, Inc., the Federal Railroad Administration, and Balfour Beatty/Zetica conducted a three-year study to develop guidelines for optimal implementation of GPR technology by North American railroads. In th...

Brief review of the use of track design models associating track life (number of load cycles) with track structural conditions to provide a basis for assessing observed track degradation trends using an example of track geometry degradation compared to expected trends.

Data from track monitoring locations at bridge-track transitions that highlight some of the main contributing factors to excessive settlement and rapid track geometry deterioration.

The presentation describes a measurement system for track deflection and several examples of cases or measurements of excessive track deflection that can affect safe track performance.

Instrumentation and results from a long term evaluation of track degradation associated with fouled ballast.

Description Get 14 peer-reviewed papers from the first-ever D18 symposium dedicated to the study of the properties and behavior of railroad ballast. Industry experts present their research on various best practices for field and laboratory ballast testing. Topics include

Professor Ernest “Ernie” Theodore Selig III was larger than life. He held a prominent position in the industry, was an inventor and entrepreneur several times over, and maintained an international reputation as an expert in two distinct specialties. His passing in August 2016 has left a void for those of us who knew him as Ernie and for the industr...

Vertical track deflection has been used as an indicator of track deterioration and quality for generations. While track roughness as indicated by track geometry indicates whether the track is adequately smooth to convey passing traffic safely and comfortably, track deflection can indicate whether the track is structurally suitable to accommodate tr...

This paper and presentation will provide survey results of fouled ballast definitions, parameters, limits/standards, and laboratory test results to assist in the creation of a straightforward procedure to measure fouling parameters based on track performance and safety. Federal Track Safety Standards (FTSS) for ballast are set forth under §213.103...

Track support is a critical necessity for reliable railroad track infrastructure. Poor track support conditions can accelerate track condition deterioration. Specific examples include rail and ties that experience increased loading in these zones. These components often shed load in poorly supported zones as components fail or material properties d...

Many locations of railroad track consist of abrupt changes in track stiffness and underlying substructure called transition zones. These regions historically experience greater track settlement than the surrounding track re-quiring more frequent track maintenance from railroad companies. This paper emphasizes how discontinuities at the tie-ballast...

A site investigation of a track geometry degradation zone along the Northeast Corridor in Northeastern Maryland uncovered track problems that included drainage, fouled ballast, and excessive concrete tie wear. The site conditions were characterized using ground penetrating radar, track deflection, test pit excavation and sampling, and track geometr...

Premature concrete tie failures have been investigated and found to be caused by a variety of contributing factors. While no specific failure cause was identified in some investigations, it is clear that tie support conditions play a role since the tie support can dramatically affect internal tie load distribution. In addition, the existence of gap...

This paper describes the use of Spectral Analysis of Surface Wave (SASW) for characterizing rail track ballast and foundation layers. Surface wave testing on a rail track is more complicated than on soil sites or pavements due to the presence of large ballast void spaces, crossties, and rails as well as the complex variation of shear-wave velocity...

Track support is necessary for reliable, resilient railroad track infrastructure. Ability to recover quickly from adversity is a hallmark of the railway industry, and ability to rapidly restore track to service is a main element contributing to resilience of rail service. Poor track support conditions can increase dynamic and impact loading on trac...

Paper presents results of FRA sponsored study on relationship between geometry defects and rail defects and specifically the relationship between presence of one of more track geometry defects and development of rail defects at that same location. In this study, approximately 335,000 track geometry defects were correlated with approximately 26,000...

In July 2003, under cooperative research funding from the Federal Railroad Administration and the Portland Cement Association, an extensive field testing program was started by the Transportation Technology Center, Inc. Under this testing program, two types of slab track were designed and installed on the High Tonnage Loop (HTL) located at the Tran...

This paper presents the equipment and Spectral Analysis of Surface Wave (SASW) approach for non-invasively characterizing railroad track ballast and foundation layers. Surface wave testing on a railroad track is more complicated than that on soil sites or pavements because of the presence of ballast, crossties, and rails as well as the complexity o...

Ballast fouling is a problematic track condition that can lead to inadequate ballast performance. Prioritizing remediation of fouled ballast sites is difficult because no relationship between ballast fouling and track performance exists and fouled ballast performance depends on the amount, grain-size, type, plasticity, and moisture content of the f...

One of the more critical failure modes of concrete crossties in North America is the degradation of the concrete surface at the crosstie rail seat, also known as rail seat deterioration (RSD). Loss of material beneath the rail can lead to wide gage, cant deficiency, reduced clamping force of the fastening system, and an increased risk of rail rollo...

This paper discusses two instrumentation techniques, linear variable differential transformers (LVDTs) and accelerometers, used to monitor and evaluate track structure behavior with the goal of nondestructively and quickly identifying track structural problems that eventually cause track geometry problems. LVDT results at a poorly performing bridge...

Links Geotechnics with Railway Track Engineering and Railway Operation Good railway track and railway operations depend on good geotechnics, in several different ways and at varying levels. Railway Geotechnics covers track, track substructure, load environment, materials, mechanics, design, construction, measurements, and management. Illustrated by...

Recent investigations of bridge transition zones experiencing reoccurring track geometry issues have exhibited unsupported ties along the approach near the bridge deck. These unsupported ties are identified as problematic as they can increase the loading of the ballast by mechanisms of impact loads and load redistribution. The development of unsupp...

A reoccurring maintenance issue for railroads in the United States is differential movement at bridge transitions and a common cause of this movement is the existence of gaps and load redistribution within the track system. These gaps can increase the applied loads in the track system with two examples being gaps between the rail and tie fastening...

This paper describes the use of Spectral Analysis of Surface Wave (SASW) for characterizing rail track ballast and foundation layers. Surface wave testing on a rail track is more complicated than on soil sites or pavements due to the presence of large ballast void spaces, crossties, and rails as well as the complex variation of shear-wave velocity...

This paper presents a conceptual model of tie-ballast interaction for high-speed passenger and freight railroads. The main components of the model are inclusion of a gap between the tie bottom and underlying ballast and a cubic function to model the tie-ballast load-displacement behavior. Field measurements from high-speed passenger and freight rai...

Railway transitions such as bridge approaches experience differential movements related to differences in track system stiffness, track damping characteristics, foundation type, ballast settlement from fouling or degradation, as well as fill and subgrade settlement. Identification of factors contributing to this differential movement and developing...

http://onlinepubs.trb.org/onlinepubs/trnews/trnews286.pdf see page 22

Railway ballast is a critical element in the railway track support structure. The ballast is often overlooked when inspection tools are developed for track. When ballast is not functioning correctly, the strength of the track structure may be inadequate and thus compromise track stability. Track stability-related failures vary from rapid deteriorat...

With the first major installation in North American railroads during the 1960’s, concrete ties were believed to last longer than timber ties and have the potential for reduced life cycle costs. However, their characteristic response to initial pretension release as well as dynamic track loading is not well understood. In North America, concrete tie...

Track substructure design is an often overlooked step in the design of railroad track. The lack of consideration for the substructure when designing track results in greater maintenance demands due to inadequate track substructure performance. Railway track is a stable structure with a progressive failure process that allows track engineers to mana...

Over the past few years, significant progress has been made using ground penetrating radar (GPR) technology to assess track substructure (ballast, subballast, and subgrade) conditions. Several GPR technologies developed in the United States and Europe have shown great potential as production inspection tools for testing ballast, subballast, and sub...

This paper presents design and construction details of two types of slab track installed at the Facility for Accelerated Service Testing (FAST), near Pueblo, Colorado. Direct fixation slab track (DFST) and independent dual block track (IDBT) were installed on a 5-degree curve with 4-inch superelevation. The slab track test section was 500 feet long...

Today, networks of legacy and newer sophisticated sensors and actuators that combine reconfigurable gigascale semiconductor technology with emerging micro-mechanical systems (MEMS) and nanotechnology subsystems (i.e. bio-systems/chemical/fluidics/photonics/ etc) are being designed and deployed in almost every area of technology that impacts human e...

High traffic volume, heavy axle loads, and high train speed can produce large rail bending stresses which contribute to increased track deterioration. Rail stress problems are further exacerbated by poor support conditions such as abrupt changes in vertical track modulus and poor track geometry. This paper summarizes the development of a measuremen...

Analysis of test results and subsequent recommendations for development of a moving track deflection measurement system. The results of the test confirm that each of the three systems tested may identify distinct characteristics of the track structure affecting track geometry deterioration. Track structure condition and deterioration are described...

The Federal Railroad Administration (FRA) has been conducting research to develop a technique that can measure the ability of the track to support vertical loads as an indication of the structural condition of the track. Track geometry specifications control the position of the rail to ensure safe and smooth train operations, however cases of unsta...

Measurement of track load-deflection behavior is anticipated to provide much needed insight into the characteristics of track support affecting all aspects of railway track engineering: safety evaluation, maintenance, and rehabilitation. The vertical load-deflection behavior of track under dynamic loading as indicated by track stiffness or modulus...

Recent gage restraint measurement system (GRMS) developments include the redesign of GRMS vehicles using a deployable split-axle instead of a freight truck mounted split-axle. This new test configuration results in boundary condition changes in the applied loads and split axle location, which influence test results. To ensure the equivalence of tes...

Recent gage restraint measurement system (GRMS) developments include the redesign of GRMS vehicles to conduct testing from a deployable axle instead of using freight truck mounted axle and GRMS on hi-rail vehicles. This new test configuration results in boundary condition changes in the applied loads and split axle location; both of which influence...

Executive Summary Track degradation at track stiffness transitions is a leading cause of poor performance and is also a weak link in the performance of all track corridors, especially those slated for high-speed operations subject subpart G Track Safety Standards (CFR 213). Problems that commonly develop at track stiffness transitions that affect t...

An instrumentation program was undertaken to evaluate the relative damage to railway track from various classes of traffic: loaded freight, empty freight, passenger, and high-speed intercity. As part of this investigation, the roadbed deflection was targeted for measurement since the roadbed deflection is the main characteristic differentiating tra...

Comparative tests were conducted to evaluate the gage restraint measurement system (GRMS) testing capabilities of a railbound GRMS vehicle, Federal Railroad Administration’s (FRA’s) T-6, and a hi-rail vehicle, Holland Company’s TrackStar GRMS system. The test objectives were to compare the performance of the two vehicles by monitoring the testing c...

Two embankments with track performance problems related to embankment instability were investigated. Both sites demonstrated potential for GPR to identify substructure instability resulting in track settlement. The capability to non-destructively evaluate track condition and diagnose the problem cause will ensure that ensuing maintenance addresses...

The development of high-speed railroad corridors in the United States is being considered by Congress as a fuel efficient and economical alternative to air or highway passenger travel. The existing infrastructure is, in many cases, suitable for freight traffic but not for the more exacting geometry standards of high-speed rail passenger trains. In...

Adequate lateral resistance is required to provide the stable track structure necessary for safe rail operations on passenger and freight railroad track. Insufficient lateral resistance coupled with a large thermal compression force in the rail from high rail temperature could buckle the track structure. Railroads typically employ mechanical stabil...

Adequate lateral resistance is required to provide the stable track structure necessary for safe rail operations on passenger and freight railroad track. Insufficient lateral resistance, coupled with a large thermal compression force in the rail from high rail temperature, can buckle the track structure. Railroads typically use mechanical stabiliza...

A research project is being conducted to identify methods of using ground penetrating radar (GPR) to improve railway track condition assessment and enhance track inspections and safety. The safety of passing traffic can be improved if better indicators of problematic track conditions can be developed and utilized to better inspect the track for saf...

Investigations of track maintenance problem sites pointed out the need for a system that could correlate a wide variety of relevant information to understand track failure mechanisms and to improve maintenance decisions. Obtaining information related to track features, track geometry, maintenance, and traffic tonnage proved to be difficult because...

Investigations of track locations that are not performing well have provided data indicating that GPR has strong potential as a tool for evaluating the condition of track and diagnosing the cause of track performance problems. The investigation of two railway embankments with track performance problems related to embankment instability provide good...

Locations of rapid track condition deterioration are typically well known to railway track engineers, although the cause and methods of improvement may be unclear. The rapid deterioration of these locations can be due to many factors such as poor conditions of the components (rail, tie, and ballast) or failure of any of the components or subgrade....

Railway track engineers are focused on cost-effective track maintenance to support revenue train traffic. Therefore, effective detection of railway track maintenance needs and planning of maintenance activities are required to improve efficiency. One area requiring improvement to ensure safe train operations and efficient maintenance is identificat...