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    <title>Transport Research International Documentation (TRID)</title>
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    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
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    <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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      <title>Shrinkage and Temperature Forces in Frame Piers</title>
      <link>https://trid.trb.org/View/2196872</link>
      <description><![CDATA[Shrinkage and temperature forces are known to have short- and long-term effects on both the superstructures and substructures of bridges. In the substructure, such effects are more pronounced if frame piers are used, given their volumetric change is often restrained. The main objective of this research was to investigate the forces developed in frame piers and their supporting foundations due to volumetric changes caused by thermal and shrinkage effects. For this purpose, a set of finite element (FE) models capable of simulating shrinkage strain, creep strain, thermal strain, strength development of concrete, and nonlinear behavior of concrete were developed and calibrated using experimental test results. Field data were then collected from bridges instrumented with vibrating wire strain gauges embedded in the frame piers at the time of construction. Further to obtaining firsthand information from the field, the FE models were validated using collected field data. Various frame pier geometries were then analyzed using the validated model to identify the most susceptible geometries. The results of the study indicated that frame piers cast in Iowa on warm summer days, particularly in June and July, experience the most demand from temperature and shrinkage effects compared to frame piers cast at other times of the year. The most critical factors affecting frame pier susceptibility were found to be column stiffness, length of the cap beam, and flexural stiffness of the cap beam. Column stiffness was observed to be the most impactful factor on the susceptibility of frame piers to these effects. Basic susceptibility metrics, such as the length of the frame and the length-to-height ratio of the frame, were found to be not accurate enough to predict susceptibility, as accurate susceptibility metrics must account for column stiffness and column restraint factors. These results led to the development of two-dimensional linear elastic models that simplified the assessment process without losing accuracy. Overall, the requirements set by the Iowa DOT’s Bridge Design Manual were found to be adequate in capturing the performance of frame piers subjected to temperature and shrinkage forces.]]></description>
      <pubDate>Tue, 25 Jul 2023 16:33:35 GMT</pubDate>
      <guid>https://trid.trb.org/View/2196872</guid>
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    <item>
      <title>Sensor-assisted Condition Evaluation of Steel and Prestressed Concrete Girder Bridges Subjected to Fire – Phase II</title>
      <link>https://trid.trb.org/View/1582119</link>
      <description><![CDATA[The overarching goal of this multi-phase study is to develop and validate a post-fire condition evaluation method for steel- and prestressed concrete-girder bridges (overpasses or viaducts) based on material and structural data, a fire scenario (e.g., a fuel tank on highway), and environmental factors (e.g., moisture and wind). The proposed method involves fire dynamics simulation underneath a bridge, thermomechanical analysis of the structure, and structural condition assessment against material strengths. One of the key challenges to achieve this goal is to measure strains in steel members on fire in order to validate various computational models.

The first phase aimed to understand and validate the performance of distributed fiber optic sensors for temperature and strain measurements, and validate a fire dynamics simulator and a thermomechanical model with measured data. Large-scale composite specimens were tested in a controlled compartment fire. 
The second phase aims to improve the deployment scheme and data quality of distributed fiber optic sensors embedded in concrete and attached on steel members, understand and quantify the effect of multiple steel girders on the aerodynamics and heat distribution of a fire, and develop and validate fire dynamics and thermomechanical models with the testing of small-scale multi-girder bridge superstructures. Each specimen will be composed of a reinforced concrete (RC) deck on three steel girders with shear studs and evaluated in three steps. First, the fire dynamics surrounding structural elements will be predicted based on the capacity of a fuel tank in representative vehicles. Second, heat will be transferred from the surface to inside the elements. Third and finally, the behavior and condition of the bridge elements under gravity loads are evaluated during and after a fire scenario as a result of fuel tank spilling on highway bridges.
]]></description>
      <pubDate>Tue, 05 Feb 2019 16:18:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/1582119</guid>
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    <item>
      <title>Thermal Gradients in Southwestern United States and the Effect on Bridge Bearing Loads</title>
      <link>https://trid.trb.org/View/1479844</link>
      <description><![CDATA[Thermal gradients became a component of bridge design after soffit cracking in prestressed concrete bridges was attributed to nonlinear temperature distribution through the depth of the bridge. While the effect of thermal gradient on stress distributions has been previously investigated in concrete bridges, less research has been done investigating the effect on bearing loads. The climate condition of the southwestern portion of the United States may cause larger thermal gradients than recommended by AASHTO LRFD Bridge Design Specifications. The main objective of this study was to evaluate the effect of thermal gradients in the southwestern region of the United States on bearing design. This study consisted of two parts, heat flow analysis using long-term meteorological data and two case study bridges in Nevada analyzed for bearing loadings including several variations of thermal gradient loading. One bridge was a two-span concrete posttensioned box girder bridge in Las Vegas, the second bridge was a two-span composite steel girder bridge in Reno. Heat flow analysis was conducted using meteorological data from weather stations in Northern and Southern Nevada to evaluate the AASHTO LRFD thermal gradient recommended for Nevada. Results showed that AASHTO LRFD Zone 1 thermal gradient is an unconservative estimate of conditions in the southwestern states for both concrete and composite superstructures. Analysis in CSiBridge using area models of the concrete bridge in Las Vegas indicated that the largest predicted thermal gradient obtained through heat flow analysis increased total exterior bearing loads 12% relative to total load including the AASHTO thermal gradient. Analysis using area models of the composite steel girder bridge in Reno indicated that the unaltered temperature profile obtained through heat flow increased the total exterior bearing 27% relative to total load including the AASHTO thermal gradient at Abutment 1. Variation of constant temperature through the steel girder influenced both longitudinal and transverse loading. Reducing the temperature through the girder maximized bending moment and support reactions, while unaltered temperature through the girder maximized individual bearing loads. Thus, it is uncertain whether constant temperature through girder should be included.]]></description>
      <pubDate>Tue, 29 Aug 2017 10:09:35 GMT</pubDate>
      <guid>https://trid.trb.org/View/1479844</guid>
    </item>
    <item>
      <title>Field Evaluation of Hybrid-Composite Girder Bridges in Missouri</title>
      <link>https://trid.trb.org/View/1320886</link>
      <description><![CDATA[Three hybrid composite beam (HCB) bridges were recently constructed in Missouri, USA. HCB is an innovative idea that incorporates traditional construction materials (steel and concrete) with fiber reinforced polymer (FRP) composites in such a manner to optimize the performance of the beam constituents. The HCB consists of self-consolidating concrete (SCC) poured in classical arch shape and tied at the ends by conventional prestressing strands. The concrete and steel are tucked inside durable fiberglass shell and the voids are filled with polyiso foam. An integrated study was implemented on the three bridges to investigate the HCB in-service behavior. The study included quality control/quality assurance (QC/QA) testing program. As a part of this research study, an innovative infrared (IR) thermal imaging approach was developed to detect the voids in the concrete arch section during its casting. The approach is found to be an ideal solution for QC/QA of the concrete arch concrete placement. A series of load tests on the bridges together with meticulous theoretical and numerical analyses were executed. The first finite element analysis (FEA) for a HCB bridge superstructure was accomplished. The analysis was used to provide better understanding for the girder behavior and to emphasize the areas that need more examination. Based on the FEA results the existing flexural design methodology and assumptions were tested. The methodology was found unable to detect the maximum compressive stress in the concrete arch, and the strain compatibility assumption was found invalid. However, the experimental measurements along with the mathematical calculations indicate that the HCB owns abundant nominal bending and shear strength to withstand the expected loads during its lifetime. A modified methodology that is based on the same assumptions as the existing one was produced. The methodology was found to achieve significant enhancement in predicting the stresses under the service loads. The durability of the HCB was tested through subjecting the composite shell to different aging regimes. The testing results indicate that the HCB possesses excellent durability in relation to the expected weathering exposure in Missouri. Longer exposure regimes are currently being examined to verify these results.]]></description>
      <pubDate>Tue, 26 Aug 2014 11:00:21 GMT</pubDate>
      <guid>https://trid.trb.org/View/1320886</guid>
    </item>
    <item>
      <title>Temperature Effects on a Box-Girder Integral-Abutment Bridge</title>
      <link>https://trid.trb.org/View/1309410</link>
      <description><![CDATA[As part of a study to quantify temperature effects on integral-abutment box-girder bridges, field instrumentation was monitored continuously for one year on a bridge near Sacramento, California. Thermocouples were installed throughout the deck as well as over the height of the superstructure. Temperature changes were used to obtain maximum and minimum average temperatures as well as positive and negative thermal gradients. These values were compared with recommended respective temperature ranges. Strain changes at various locations were obtained by driving trucks along five load paths. These data, along with strain changes resulting from daily temperature variations, were used to validate a finite-element model using solid elements for the superstructure and springs at the abutments, in order to replicate the partial fixity of the bridge. The validated finite-element model was used to evaluate the effects that the partial fixity and temperature gradients have on the temperature stress for a typical integral-abutment bridge.]]></description>
      <pubDate>Tue, 10 Jun 2014 13:18:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/1309410</guid>
    </item>
    <item>
      <title>Relaxation of cyclic temperature loads on concrete bridge superstructures</title>
      <link>https://trid.trb.org/View/1194641</link>
      <description><![CDATA[All bridges are subjected to cycles of heating and cooling both summer and winter.  For a continuous bridge, heating of the superstructure tends to cause upward curvature resulting in stress effects because the superstructure must remain compatible with its supports.  For both continuous and simply supported bridges, there is another less important stress effect caused by the shape of the temperature distributions which naturally occur within the superstructure. These stresses are referred to as internal compatibility stresses.  A temperature distribution imposed on a bridge superstructure is considered to be a temperature load.  In this thesis, a series of temperature loads derived from field data are imposed on mt henry bridge in Perth, Western Australia, in a computer model which examines their effect as a stress relaxation analysis. The field data is simplified to enable generalisations to be made about the relationship of temperature and stress, and the effect of these simplifications is shown to be fairly minor.  The sensitivity of the analysis to material properties and the range of error of measured data is examined. It is demonstrated that, subject to certain qualifications, the analysis can be applied to most concrete bridges.  The actual method of analysis is then outlined and the outcomes are examined.]]></description>
      <pubDate>Fri, 24 Aug 2012 13:59:22 GMT</pubDate>
      <guid>https://trid.trb.org/View/1194641</guid>
    </item>
    <item>
      <title>Cracking in large-sized long-span prestressed concrete AASHTO girders</title>
      <link>https://trid.trb.org/View/1168678</link>
      <description><![CDATA[An investigation was conducted to study a cracking problem associated with the production of large-sized long span prestressed concrete AASHTO girders. During the production of these girders in the prestressing plant, vertical cracks often develop near the mid-third of the span after the girders have been cured overnight on the casting bed and before the prestressing strands are detensioned.  The cracks would extend across the top flange of the girder transversely and penetrate vertically down through the girder web, reaching toward the bottom flange.  The objective of the investigation was to identify the cause(s) of the problem, and to develop and recommend its remedies.  The research included a national survey of prestressed concrete producers to assess the status of the problem, a literature review of relevant issues, a series of laboratory and field studies to determine the condition of concrete and tendon force during the curing period, and an analysis of the girder under restrained thermal contraction.  The most probable cause of the cracking problem was due to restrained thermal contraction of the entire casting system (ie the girders with the linking tendons) during the cooling period after the overnight steam or heat curing.  The potential for cracking the girder may be minimised by increasing the total length of the exposed tendons outside the girders, or by reducing the cooling period and thus minimizing the temperature reduction as much as possible.  The cracks caused by the restrained thermal contraction are closed immediately as soon as prestressing tendons are detensioned.  Given an  adequate supply of moisture, the cracks will heal and the concrete will virtually regain its full strength.]]></description>
      <pubDate>Thu, 23 Aug 2012 19:51:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/1168678</guid>
    </item>
    <item>
      <title>Thermal Movements of Continuous Concrete and Steel Structures</title>
      <link>https://trid.trb.org/View/849668</link>
      <description><![CDATA[In an effort to avoid the problems caused by expansion devices, Tennessee bridges in recent years have been designed and built with provision for expansion only at the abutments.  This practice has produced considerable cost savings and caused no serious problems; as a result the practice has been extended to bridges with longer and longer lengths.  It was a decision relative to the design and construction of a 2,700-ft. long prestressed concrete bridge on State Route 137 over the Holston River at Long Island at Kingsport, Tennessee, that led to the research project described in this paper.  The bridge consists of (1) prestressed, precast concrete box girders, (2) prestressed, precast concrete sub-decking, and (3) cast-in-place concrete deck which acts monolithically with the girders and the sub-deck.  Also, diaphragms are cast on top of each pier to fill the gap between ends of the girders.  These diaphragms are tied to the piers by 1-in. diameter, smooth bar dowels.  Reinforcing steel in the deck is continuous over the piers.  Thus, the bridge supports applied loads by acting as a continuous structure.  There were two primary objectives to the bridge research: (1) to assess the adequacy of the bridge, as designed and built, to function in an adequate manner and (2) to gain a better understanding of the complex relationship which exists between ambient temperature, temperature distribution through the superstructure, stresses in both the deck and the piers, and longitudinal movement of the bridge.]]></description>
      <pubDate>Mon, 25 Feb 2008 14:36:40 GMT</pubDate>
      <guid>https://trid.trb.org/View/849668</guid>
    </item>
    <item>
      <title>DYNAMICS OF SEISMIC POUNDING AT EXPANSION JOINTS OF CONCRETE BRIDGES</title>
      <link>https://trid.trb.org/View/487646</link>
      <description><![CDATA[Motivated by a need to understand the effects of earthquake-induced pounding at thermal expansion joints of concrete bridges, the first part of this paper deals with collinear impact between concrete rods of the same cross section but different lengths.  It is shown that the coefficient of restitution between rods depends only on the length ratio and the damping ratio of the rod material and that the duration of impact is equal to the fundamental period of axial vibration of the shorter rod.  These results are then used in the second part of this paper to formulate a realistic yet simple analysis of seismic pounding in concrete bridges.  In determining a suitable value of the coefficient of restitution, use is made of the strong-motion data recorded on a concrete bridge that experienced significant pounding during recent California earthquakes.  It is shown that seismic pounding generally reduces the column forces, that large impact forces generated in the superstructure are not transmitted to the bridge columns and foundations, and that pounding does not increase the longitudinal separation at the hinges.]]></description>
      <pubDate>Sat, 01 Aug 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/487646</guid>
    </item>
    <item>
      <title>THE DESIGN OF INTEGRAL CONCRETE BRIDGES</title>
      <link>https://trid.trb.org/View/372693</link>
      <description><![CDATA[This article, which is a practitioner's approach to the design of integral bridges, reviews the history of its development, discusses its various aspects, and notes that the structural continuity typical of integral bridges alter the distribution of secondary effects (shrinkage, creep, thermal gradients, etc.), the lateral and longitudinal loads applied to superstructures, and superimposed dead and live loads.  This continuity induces secondary effects due to the generation of passive pressures in the abutment backfill.  It is pointed out that the design of integral bridges should be simplified and standardized by following 3 steps: the basic bridge details should be crafted to minimize secondary effects (by following certain steps here listed); the application range for such bridges should be limited until initial design standards have been proven; the continuity connections at abutments and over the piers should be standardized for the established application ranges.]]></description>
      <pubDate>Wed, 02 Jun 1993 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/372693</guid>
    </item>
    <item>
      <title>SESSION 5: ANALYSIS AND DESIGN II. SECOND INTERNATIONAL CONFERENCE ON SHORT AND MEDIUM SPAN BRIDGES: AUGUST 17-21, 1986, OTTAWA, ONTARIO, CANADA: PROCEEDINGS VOLUMES 1 AND 2</title>
      <link>https://trid.trb.org/View/291052</link>
      <description><![CDATA[Papers presented at session 5 were as follows: finite element modelling of stiffened steel box girders (el aghoury,m); new development of the finite strip method for bridge deck analysis (cusen,ar); geometry and design of bridge piers (green,r); thermal interaction between continously welded rail and elevated transit guideways (grouni,hn); Anchorage zone simulation using the finite element method (grondin,r); thermal effects on composite box girder bridges during construction (branco,fa); rail-structure interactions for short span railway and transit bridges (magued,mh); 3-d analysis of free vibration of truss bridges (aida,t); warping torsion and its significance in the design of concrete box girder bridges (waldron,p); aseismic design of a skewed multi-span highway bridge (harvey,di).  For the covering abstract of the conference see IRRD 291033.  (TRRL)]]></description>
      <pubDate>Tue, 31 Jan 1989 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/291052</guid>
    </item>
    <item>
      <title>SESSION 4B: RESEARCH AND DEVELOPMENT. SECOND INTERNATIONAL CONFERENCE ON SHORT AND MEDIUM SPAN BRIDGES: AUGUST 17-21, 1986, OTTAWA, ONTARIO, CANADA: PROCEEDINGS VOLUMES 1 AND 2</title>
      <link>https://trid.trb.org/View/291051</link>
      <description><![CDATA[Papers presented at session 4b were as follows: effects of time-dependent concrete properties on prestress losses (shiu,kn); nonlinear temperature distributions in bridges at different locations in the USA (potgieter,ic); fatigue strength of prestressed concrete girder bridges (al-zaid,rz); development of short span bridges or viaducts without expansion joints (suruga,t); experimental and analytical load distribution behaviour of glued laminated timber deck bridges (wipf,tj); response of multi-support highway bridge to spatial variation of ground motions (loh,ch); problems with coupling joints of prestressing tendons in continuous post-tensioned concrete bridges (seible,f); using strong-motion earthquake records to examine the seismic response of highway bridges (wilson,jc); cost-effective, short-span bridge systems : a selection concept and an optimization procedure (mafi,m); structural reliability of plate girder with secular decrease of high-strength bolt pretension (nishimura,a). For the covering abstract of the conference see IRRD 291033.  (TRRL)]]></description>
      <pubDate>Tue, 31 Jan 1989 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/291051</guid>
    </item>
    <item>
      <title>THERMAL STRESS ANALYSIS OF CONCRETE BRIDGE SUPERSTRUCTURES</title>
      <link>https://trid.trb.org/View/53650</link>
      <description><![CDATA[Only mean temperature changes are generally considered in the design of concrete bridge superstructures.  Because of daily changes in both ambient temperature and intensity of solar radiation, temperature differentials also exist in concrete superstructures.  These temperature differentials induce stresses throughout the depth of concrete structures, which are generally not included in current design procedures.  This paper describes the heat transfer processes that occur between the atmosphere and a concrete superstructure and also the climatic conditions necessary for the development of temperature differentials during both summer and winter temperature-time analyses, computed by using a one-dimensional heat flow analysis, indicate that the distribution of temperature throughout the depth of a superstructure is nonlinear and is a function of superstructure depth.  Stresses associated with the nonlinear temperature gradients are described.  These stresses can be several times those due to live load, specially in continuous systems.  The stresses predicted from the idealized distributions are compared to those obtained by using the heat flow analysis.  The results indicate that the idealized distributions have limited design value.  Simple empirical design expressions are developed for both thermal stresses and curvature.  These are based on typical climiatic data for summer and winter conditions and can be applied to a variety of cross-sectional superstructure geometries.  An example of the stresses induced by thermal loading on a two-span box-girder superstructure is given.  /Author/]]></description>
      <pubDate>Wed, 28 Sep 1977 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/53650</guid>
    </item>
    <item>
      <title>THERMAL STRESSES IN CONCRETE BRIDGE SUPERSTRUCTURES UNDER SUMMER CONDITIONS</title>
      <link>https://trid.trb.org/View/35763</link>
      <description><![CDATA[Current design practice for deep concrete bridge superstructures generally ignores the influence of the diurnal heating cycle on the flexural response of members and instead, considers mean temperature effects. A 1-demensional heat-flow analysis is used to study the flexural deformations and stresses that are developed in deep concrete sections as a result of a typical summer heating cycle. Both nonlinear temperature and stress distributions are observed, and nonlinearity increases with member depth. An analysis of 2 typical continous concrete structures indicates stresses exceeding those associated with live load and amounting to 40 percent of the allowable area possible for concrete structures having a depth of more than 4 ft (1.22 m).]]></description>
      <pubDate>Fri, 14 May 1976 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/35763</guid>
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