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    <title>Transport Research International Documentation (TRID)</title>
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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
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      <title>Transport Research International Documentation (TRID)</title>
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    <item>
      <title>FAST/HAL TRACK LOADS EVALUATION</title>
      <link>https://trid.trb.org/View/499934</link>
      <description><![CDATA[The Track Loads Evaluation was conducted to quantify vertical and lateral forces at FAST under 33- and 39-ton axle load cars. A train of 14 each of 33- and 39-ton axle load cars was operated at 42 mph and vertical and lateral rail forces were measured at two separate locations in 5-degree curves using instrumented rails.  Vertical rail forces beneath the 39-ton axle load cars were found to be 25% to 35% higher than those beneath the 33-ton axle load cars.  Lead-axle lateral rail forces were from 13% to 28% higher under the 39-ton axle load cars.  However, there were no significant differences in L/V ratios.  (33-ton=66,000 lb; 39 ton=69,000 lb; 42 mph=67 kmh)]]></description>
      <pubDate>Thu, 29 Apr 1999 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/499934</guid>
    </item>
    <item>
      <title>FAST/HAL MECHANICAL COMPONENT PERFORMANCE TEST</title>
      <link>https://trid.trb.org/View/499935</link>
      <description><![CDATA[As part of the Heavy Axle Load program, an experiment was conducted to evaluate the effect of heavier axle loads on wheel performance.  Comparative wear performance data for 33- and 39-ton axle load vehicles were generated by the experiment. Results obtained in the experiment indicate that on a car mileage basis there is no statistically significant difference in wheel flange and rim wear for the 33- and 39-ton axle load cars.  (33 ton=66,000 lb; 39 ton=69,000 lb)]]></description>
      <pubDate>Thu, 29 Apr 1999 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/499935</guid>
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    <item>
      <title>FAST/HAL RAIL PERFORMANCE TEST</title>
      <link>https://trid.trb.org/View/499936</link>
      <description><![CDATA[As part of the Heavy Axle Load Program, the rail performance experiment was conducted to evaluate the effect of increasing axle loads on rail wear and fatigue development.  Data accumulated under 33- and 39-ton axle load vehicles was compared for various types of rail metallurgies.  Results indicated increased wear rates and fatigue initiation under 39-ton axle loads.  (33 ton=66,000 lb, 39 ton=69,000 lb)]]></description>
      <pubDate>Thu, 29 Apr 1999 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/499936</guid>
    </item>
    <item>
      <title>FAST/HAL RAIL WELD PERFORMANCE</title>
      <link>https://trid.trb.org/View/499937</link>
      <description><![CDATA[Flash butt welds and alumothermic thermite welds were exposed to 150 MGT of 39-ton (69,000 lb) axle load service during testing at the Facility for Accelerated Testing Transportation Test Center, Pueblo, Colorado.  Flash butt welds developed horizontal split web whereas thermite welds experienced a multitude of defects ranging from shrinkage porosity, which led to horizontal split webs failures and subsurface shelling of the head leading to rapid deterioration of the gage side of the rail head.  The development of post weld heat treatment methods for thermite welds and an improved weld mold design has been initiated as a result of these tests.  Furthermore, flash butt weld plants are contemplating different methods of producing a higher quality finish on webs to prevent cracks from initiating.]]></description>
      <pubDate>Thu, 29 Apr 1999 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/499937</guid>
    </item>
    <item>
      <title>FAST/HAL PILOT RAIL GRINDING TEST</title>
      <link>https://trid.trb.org/View/499938</link>
      <description><![CDATA[Tests on North American railroad systems have shown that benefits can be gained by scheduling periodic rail grinding programs.  These benefits include a reduction in the occurrence of internal rail defects and rail surface contact fatigue defects, such as gage corner spalling and head checking.  A pilot grinding test was performed to serve as a guide to prepare future grinding experiments.  Four different rail profiles were tested in a 6-degree curve and were exposed to 145 MGT of lubricated heavy axle load traffic.  The conditioned rail, with 15 MGT of dry operation, did not form shells or detail fracture defects whereas the rails with asymmetrical and ground worn profiles did.  There is, however, a possibility that rail cleanliness may have been a variable that confounded the experimental results.]]></description>
      <pubDate>Thu, 29 Apr 1999 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/499938</guid>
    </item>
    <item>
      <title>OVERVIEW OF THE FAST/HAL RAIL PERFORMANCE TESTS</title>
      <link>https://trid.trb.org/View/499939</link>
      <description><![CDATA[Evaluation of wear data suggests that position-in-curve effects have occurred.  The most reliable data shows no increase in gage face wear rate occurs in head hardened rail when the wheel load is increased from 33 kips to 39 kips under dry conditions.  But under contaminated conditions, the gage wear rate increases by up to 40% for the same premium metallurgies.  The effect of wheel load on defect occurrence rate is not clear cut on a rail-to-rail basis.  But for specific rails subjected to both wheel loads, the increase in the defect rate is dependent on hardness being least for the premium metallurgies.  The asymmetric ground profile has again yielded bi-planar shells which were quick to turn to detail fractures.  That profile was also associated with lubricated gage face wear rates many times greater than those associated with more conformal profiles although they were still about 1/3 of the rates occurring under dry conditions.]]></description>
      <pubDate>Thu, 29 Apr 1999 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/499939</guid>
    </item>
    <item>
      <title>FAST/HAL WOOD TIE AND FASTENER EXPERIMENT</title>
      <link>https://trid.trb.org/View/499940</link>
      <description><![CDATA[Wood ties and fastening systems were installed in two 5-degree curves and in a 6-degree curve and were subjected to 160 MGT of heavy axle load traffic.  Comparison of static force and displacement data collected under similar conditions indicates that rail base displacement and rotation values measured during the program are greater than values measured during the 33 kip program.  Other results show rail fastened with cut spikes will displace laterally twice as much as rail fastened with elastic fasteners at L/V ratios around 0.5.  Fastener failures and maintenance demand were minimal and limited to one fastener type.  Tie plate cutting is limited to the field side of the low rail on the 6-degree curve.]]></description>
      <pubDate>Thu, 29 Apr 1999 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/499940</guid>
    </item>
    <item>
      <title>FAST/HAL CONCRETE TIE AND FASTENER EXPERIMENT</title>
      <link>https://trid.trb.org/View/499941</link>
      <description><![CDATA[Six different designs of concrete ties were installed and subjected to 39 kip wheel loads.  Dynamic strain measurements on one tie design showed tensile strains between the two rail seats to be nearly identical for 33- and 39 kip axle load cars.  The only significant increase (13%) in strains occurred at the tie center for the highest 10% of strains in the distribution. Localized cracking was observed on 2.6% of the ties in the test zone.  No tie failures were experienced, and fastener maintenance was minimal.]]></description>
      <pubDate>Thu, 29 Apr 1999 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/499941</guid>
    </item>
    <item>
      <title>FAST/HAL BALLAST EXPERIMENT</title>
      <link>https://trid.trb.org/View/499942</link>
      <description><![CDATA[To determine if particular ballast materials are capable of supporting traffic in a heavy axle load environment, a ballast experiment was conducted under heavy axle load traffic.  Four ballast materials were tested, the quality ranging from good to marginal.  The ballast materials tested were granite, traprock, limestone, and dolomite.  Measurements were taken to monitor track geometry retention and ballast degradation at selected MGT cycles for each test ballast.  During the first 160 MGT of traffic, all four ballast materials were able to withstand the heavy axle load traffic but two ballast materials required an out-of-face surfacing due to loss of cross level.  The dolomite ballast was surfaced after 40 MGT of traffic.  Even though all four ballasts completed the test, the marginal materials have required more spot tamping where rail anomalies were present.]]></description>
      <pubDate>Thu, 29 Apr 1999 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/499942</guid>
    </item>
    <item>
      <title>FAST/HAL SUBGRADE EXPERIMENT</title>
      <link>https://trid.trb.org/View/499943</link>
      <description><![CDATA[The subgrade experiment was conducted to determine if the increase in axle load from 33-ton to 39-ton produced a significant increase in subgrade stresses.  Also if a significant increase was apparent, was the increase proportional to the increase in applied load?  A consist was operated at three different MGT cycles.  Pressure cells, extensometers, and instrumented tie plates were used to collect the data on a tangent section of the HTL track.  The results showed a significant increase in subgrade stresses with the 39-ton cars. The increase varied with the track vertical support conditions.]]></description>
      <pubDate>Thu, 29 Apr 1999 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/499943</guid>
    </item>
    <item>
      <title>FAST/HAL PERFORMANCE EXPERIMENT</title>
      <link>https://trid.trb.org/View/499944</link>
      <description><![CDATA[Turnouts on the HTL were monitored for component failures and maintenance demand during 160 MGT of heavy axle load operation. At 100 MGT a no. 20 turnout of premium components was installed replacing the existing standard component turnout.  Seventy seven percent less maintenance was recorded at the premium turnout after 60 MGT of traffic than was recorded on the standard turnout.  Component failures further point out the importance of using premium materials to extend turnout component life.]]></description>
      <pubDate>Thu, 29 Apr 1999 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/499944</guid>
    </item>
    <item>
      <title>FAST/HAL FROG PERFORMANCE TEST</title>
      <link>https://trid.trb.org/View/499945</link>
      <description><![CDATA[Five different frogs were installed in tangent track of the HTL and were subjected to 53 MGT of heavy axle load traffic. Preliminary results suggest that slight differences in geometric design can affect the early performance of frogs.  The control for this test, a standard AREA frog, has been unable to withstand the 39-ton axle loads, while premium frogs have developed only minor problems.]]></description>
      <pubDate>Thu, 29 Apr 1999 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/499945</guid>
    </item>
    <item>
      <title>FLAW DEPTH DETERMINATION IN RAILWAY FROGS VIA STEREO-RADIOGRAPHIC RECONSTRUCTION</title>
      <link>https://trid.trb.org/View/499946</link>
      <description><![CDATA[This paper will document the use of stereoradiography in an initial feasibility study for frog examination.  Given that increasing demands would be placed on all track components with the use of higher axle loads, it follows that inspection techniques would need to be more reliable, as well as provide additional information about the component being inspected.]]></description>
      <pubDate>Thu, 29 Apr 1999 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/499946</guid>
    </item>
    <item>
      <title>SUMMARY OF FIRST 160 MGT OF THE FAST/HAL PROGRAM</title>
      <link>https://trid.trb.org/View/499947</link>
      <description><![CDATA[The papers presented in the conference proceedings address the FAST/HAL program's objective of determining the engineering impact on track and mechanical components when subjected to a controlled increase in applied axle loading.  The major thrust of the program has been to document the effect of track component wear and track maintenance requirements with increased axle load.  As was expected, overall maintenance demand increased.  Additionally, the review of the results indicates that some areas in the mechanical equipment side need additional investigation, along with long term research and development.]]></description>
      <pubDate>Thu, 29 Apr 1999 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/499947</guid>
    </item>
    <item>
      <title>THE INTERRELATIONSHIPS BETWEEN TRAIN DESIGN, TRAIN HANDLING, AND LONGITUDINAL TRACK LOADING</title>
      <link>https://trid.trb.org/View/499948</link>
      <description><![CDATA[This paper discusses the advanced train handling techniques developed for the 200 car, 20800 ton  (41.6 mil lb) trains in the South African Railways.  Originally intended to save energy and reduce train action forces, significant implications for track design and maintenance cost structures were discovered. Rolling resistance and net elevation change define the minimum energy required to move a train.  Any superfluous energy is dissipated in accelerated wheel and rail wear plus track damage due to longitudinal track movement.  Longitudinally applied locomotive/track forces are related to permissible coupler forces.  Locomotive consist size is therefore a significant determinant of such forces.  Advanced driving techniques contribute further to realization of coupler strength potential, because dynamic train action is reduced and permissable quasi-static coupler forces are higher.]]></description>
      <pubDate>Thu, 29 Apr 1999 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/499948</guid>
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