<rss version="2.0" xmlns:atom="https://www.w3.org/2005/Atom">
  <channel>
    <title>Transport Research International Documentation (TRID)</title>
    <link>https://trid.trb.org/</link>
    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
    <description></description>
    <language>en-us</language>
    <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>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
    </image>
    <item>
      <title>Anchor Rod Tightening for Highmast Light Towers and Cantilever Sign Structures</title>
      <link>https://trid.trb.org/View/1092267</link>
      <description><![CDATA[Transportation agencies make extensive use of various configurations of overhead sign structures, signal structures, and luminaries.  Many of these structures are supported by a cantilevered pole, or are themselves cantilevers.  Proper performance of these structures is not only dependant on a correct design, but also on proper installation.  Field inspections have revealed the presence of loose anchor rod nuts throughout many states.  Loose anchor rod nuts in base plate connections for cantilever structures can significantly shorten the life of the structure.  Anchor rod tightening procedures exist for new installation and retightening of existing loose anchor rod nuts.  Proper installation of anchor rod nuts can preclude many problems and is easy to accomplish.]]></description>
      <pubDate>Mon, 21 Mar 2011 14:13:38 GMT</pubDate>
      <guid>https://trid.trb.org/View/1092267</guid>
    </item>
    <item>
      <title>Tests and Analysis of Cantilevered GFRP Tubular Poles with Partial Concrete Filling</title>
      <link>https://trid.trb.org/View/914278</link>
      <description><![CDATA[In this study, 6 glass fiber-reinforced polymer (GFRP) cantilevered tubular poles were tested in flexure. Four poles were filled with varying amounts of concrete; within 13, 30, 51, and 72% of their lengths, from the fixed point. Two poles, namely, a hollow and a totally concrete-filled tubes, were also tested as control specimens. The filament-wound prismatic tubes were 3,660 mm long, including a 700 mm clamped length at the fixed end, with a 220 mm outer diameter, and 4.15 mm wall thickness. The study aims at increasing flexural strength of thin-walled GFRP tubular poles by using a small amount of concrete at the vicinity of maximum moment near the base. Test results showed that flexural strength increases as the length of concrete fill is increased, until it reaches a plateau corresponding to about double the strength of the hollow tube, when the concrete fill is about one third of the clear length. This is considered the optimal condition for this tube that provides the largest strength-to-weight ratio. Poles with a shorter filling length failed prematurely, by a combined local buckling and crushing of the hollow part, while poles with a longer filling length failed at the base by rupture of the tube in tension. An analytical model was developed, validated, and used in a parametric study. The correlations between the optimal filling length ratio and both “diameter-to-thickness” ratio, and laminate structure of the tube, are demonstrated for both angle-ply and cross-ply tubes.]]></description>
      <pubDate>Tue, 16 Mar 2010 06:12:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/914278</guid>
    </item>
    <item>
      <title>Fatigue Performance of Groove-Welded Tube-to-End-Plate Connections in Highway Sign, Luminaire, and Traffic Signal Structures</title>
      <link>https://trid.trb.org/View/911363</link>
      <description><![CDATA[Fatigue performance of full penetration groove-welded tube-to-end-plate connections was evaluated by parametric studies verified by laboratory testing of full-scale galvanized cantilevered highway sign and signal and high-level luminaire structures. In the absence of sufficient experimental basis, the fatigue resistance of this connection detail in the existing AASHTO specification is defined as Category E. Fatigue performance of tube-to-end-plate connections in thin-walled tubular structures is governed by secondary out-of-plane bending stress, the magnitude of which depends on relative stiffness of the tube and end plate. In some groove-welded connections, the backing ring is welded to the tube wall, adding more variability in fatigue performance of the connection. Twenty-three full-size specimens composed of five configurations of the groove-welded connections were fatigue-tested under constant amplitude loading simulating wind-induced aeroelastic oscillations, such as galloping and vortex shedding, that are typically experienced in service. Variation in six parameters of the connection geometry were considered: diameter of tube, thickness of tube, thickness of end plate, diameter of end plate opening, number of anchor bolts, and height of backing ring. The research results demonstrated that with a suitable combination of the geometric parameters, the constant amplitude fatigue threshold of the groove-welded tube-to-end-plate connections can exceed that of AASHTO Fatigue Category D for sections widely used in highway sign, luminaire, and traffic signal structures. The local stress-based approaches provided reasonable lower bound estimates of fatigue performance of the connection detail for different geometric configurations.]]></description>
      <pubDate>Mon, 22 Feb 2010 08:51:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/911363</guid>
    </item>
    <item>
      <title>Use of Wind Power Maps to Establish Fatigue Design Criteria for Cantilever Traffic Signal Structures</title>
      <link>https://trid.trb.org/View/881209</link>
      <description><![CDATA[Recent design improvements for traffic signal and sign structures incorporate fatigue load criteria related to wind.  The Fourth Edition of the AASHTO Luminaire and Traffic Signal Specification (2001 with interims) specification is a significant change from past practice and often results in much larger and more costly structures.  Conservative principles (envelope wind demands and infinite fatigue life) for design resulted in increased cost even for those regions historically not adversely affected by wind-induced fatigue.  States that do not have steady, sustained winds and have not experienced significant fatigue failures have rightly concerns with the larger and more costly structures.  A rational basis for lowering the fatigue design loads may be appropriate.  This study compares fatigue failures with respect to wind power (expressed as a function of average wind velocity).  Inspection reports for approximate 2500 cantilevered traffic structures were collected and analyzed for suspected fatigue cracking.  Each structure was located spatially and the associated wind power classification for that location was determined.  The inspected structures were classified as cracked or non-cracked and categorized by their wind power classification and ambient average wind velocity.  The probability of a structure having fatigue cracks increases with greater wind power classifications.  Structure orientation, pole diameter, mast-arm length, in-service age, along with other details were also studied for their roles in in-service fatigue performance.  Structures in lower wind power classes have a lower probability of developing fatigue cracks.  A rational procedure for designing these structures for low wind demand regions is presented.]]></description>
      <pubDate>Mon, 30 Mar 2009 14:10:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/881209</guid>
    </item>
    <item>
      <title>Anchor Embedment Requirements for Signal/Sign Structures</title>
      <link>https://trid.trb.org/View/836586</link>
      <description><![CDATA[During the 2004 hurricane season, several anchor embedment failures of the foundations of cantilever sign structures occurred. The purpose of this research program was to determine the cause of the failure of those foundations. After a literature review, in conjunction with site investigation and testing, it was determined that the failure originated from the shear load on the anchors directed parallel to the edge of the foundation. The shear load resulted from the torsion loading on the anchor group that occurred during the hurricane. Investigations of this failure mode, based on the ACI 318-05 Appendix D provisions for concrete breakout of anchors, indicated that this is a failure mode not considered in the current design procedures for these types of foundations. Furthermore, it was determined that it very well describes the type of failure noted in the field investigation.]]></description>
      <pubDate>Mon, 22 Oct 2007 09:58:04 GMT</pubDate>
      <guid>https://trid.trb.org/View/836586</guid>
    </item>
    <item>
      <title>Technical Appendix to Computer-Based Sign, Luminaires, and Traffic Signal Support Design Tools for State and County Engineers</title>
      <link>https://trid.trb.org/View/811691</link>
      <description><![CDATA[Computer-based tools for the design of sign, luminaires and traffic signal supports were developed. The tools incorporate the latest adopted design guides and specifications [American Association of State Highway and Transportation Officials (AASHTO) 2001 Standard Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals]. Design worksheets were developed using MathCAD. They include overhead truss cantilever sign, overhead cantilever monotube traffic signal pole, overhead monotube span support, overhead truss span support, overhead truss VMS support, span wire pole, and roadside sign. Foundation design and connection design are not included. The project was conducted within the graduate research program at the University of Alabama at Birmingham and the design worksheets were reviewed by professional engineers. The final report published as University of Transportation Center for Alabama (UTCA) Report 00467 presents an overview of sign support design methodology, description and verification of the design worksheets, and conclusions and recommendations for further development. The advantages and disadvantages of the approach are discussed. Sufficient detail is presented in the final report for it to serve the technology transfer needs of the industry users as well as serve as an education tool for engineering students. This document serves as the technical appendix to UTCA Report 00467 and provides an example support structure analysis using each of the worksheets.]]></description>
      <pubDate>Wed, 18 Jul 2007 15:36:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/811691</guid>
    </item>
    <item>
      <title>Computer-Based Sign, Luminaires, and Traffic Signal Support Design Tools for State and County Engineers</title>
      <link>https://trid.trb.org/View/811687</link>
      <description><![CDATA[Computer-based tools for the design of sign, luminaires and traffic signal supports were developed. The tools incorporate the latest adopted design guides and specifications [American Association of State Highway and Transportation Officials (AASHTO) 2001 Standard Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals]. Design worksheets were developed using MathCAD. They include overhead truss cantilever sign, overhead cantilever monotube traffic signal pole, overhead monotube span support, overhead truss span support, overhead truss VMS support, span wire pole, and roadside sign. Foundation design and connection design are not included. The project was conducted within the graduate research program at the University of Alabama at Birmingham and the design worksheets were reviewed by professional engineers. The final report presents an overview of sign support design methodology, description and verification of the design worksheets, and conclusions and recommendations for further development. The advantages and disadvantages of the approach are discussed. Sufficient detail is presented in the final report for it to serve the technology transfer needs of the industry users as well as serve as an education tool for engineering students. The technical appendix published as University Transportation Center for Alabama (UTCA) Report 00467-1 provides an example support structure analysis using each of the worksheets.]]></description>
      <pubDate>Wed, 18 Jul 2007 15:36:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/811687</guid>
    </item>
    <item>
      <title>Fatigue-Resistant Design for Overhead Signs, Mast-Arm Signal Poles, and Lighting Standards</title>
      <link>https://trid.trb.org/View/786584</link>
      <description><![CDATA[Traffic signs and signals are often supported by flexible cantilevered structures that are susceptible to wind-induced vibration and fatigue. The latest version of the design specifications published by the American Association of State Transportation Officials (AASHTO) now considers fatigue as a limit state. However, most of the fatigue classifications for welded details were not based on full-scale testing, and are thought to be overly conservative. This research will address the fatigue resistance of two common mast arm-to-pole connections used in the state of Minnesota. The resistance attained experimentally aligned with current predictions using AASHTO procedures, except for in-plane loading of box connection details. As a consequence of specimen design, a variety of tube-to-transverse plate connections were also tested using multi-sided tube cross-sections with different tube diameters, tube thicknesses, as well as base plate thicknesses. The standard tube-to-transverse plate connection exhibited Category K sub 2 resistance, two categories lower than the E’ specified by AASHTO. This resistance was enhanced to Category E’ through impact treatment or Category E by doubling the base plate thickness. Gusset plates could not prevent cracking of the tube at the base plate, but the tips of the gusset plate exhibited Category E resistance.]]></description>
      <pubDate>Mon, 14 Aug 2006 16:22:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/786584</guid>
    </item>
    <item>
      <title>COM624P-Based Drilled Shaft Torque and Lateral Load Analysis Method</title>
      <link>https://trid.trb.org/View/776491</link>
      <description><![CDATA[Large cantilever-type overhead freeway signs are often supported by a single drilled shaft foundation. Under high wind loads, the cantilever arm and sign panel develop significant torque loading that is distributed to the anchor bolt array cast into the top of the drilled shaft. This torque load is applied to the drilled shaft at approximately the same time as the large lateral load and moment developed by the wind loading. An analysis procedure was used to predict the torque capacity of drilled shaft foundations during the high lateral load condition. The analysis method starts with a typical COM624P p-y–type analysis for the design lateral shear and moment at the anchor bolts. The resulting lateral soil pressures estimated along the drilled shaft sidewalls present during the lateral loading are used to estimate whether voids will be present along the drilled shaft sidewall during torque loading. The estimated drilled shaft sidewall pressures and shear strengths for areas remaining in contact are used to estimate the torque capacity of the foundation. Some applications in different soil profiles are presented. This method was used as part of the development of a standard array of drilled shaft foundations for different soil conditions for standard cantilever-type freeway sign structures used by the Michigan Department of Transportation.]]></description>
      <pubDate>Fri, 03 Mar 2006 10:27:18 GMT</pubDate>
      <guid>https://trid.trb.org/View/776491</guid>
    </item>
    <item>
      <title>A SIMPLIFIED DESIGN PROCEDURE FOR END-PLATES AND BASE-PLATES OF CANTILEVERED TRAFFIC STRUCTURES</title>
      <link>https://trid.trb.org/View/502427</link>
      <description><![CDATA[Although end-plates and base-plates are routinely used in cantilevered structures supporting traffic signs, signals, and lights, no standard procedure has been established for the design of these plates.  In this report, a simplified procedure is developed for design of end-plates and base-plates of these structures, and also for base-plates of span-wire-mounted traffic-signal structures.  The proposed procedure is based on beam-and-plate bending and torsion theories, and is intended for routine application by practicing engineers when designing plates of square configurations.  Plate thicknesses and stresses obtained using this procedure compared well with those estimated using finite-element analysis, and also supported earlier conclusions reached through physical testing.  In all, 35 base-plates from five major manufacturers of traffic poles used in New York State were analyzed in the study.  A spreadsheet program implementing the proposed procedure was also developed as an efficient tool for engineers designing these items.  Using this tool will not only expedite the design process, but also facilitate optimizing plate sizes, because various design alternatives can be easily investigated and the optimal alternative rationally selected.]]></description>
      <pubDate>Mon, 19 Jul 1999 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/502427</guid>
    </item>
  </channel>
</rss>