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    <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" />
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    <language>en-us</language>
    <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>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
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    <item>
      <title>FIELD STUDY OF PREDEFLECTED STEEL-CONCRETE COMPOSITE BRIDGE</title>
      <link>https://trid.trb.org/View/102895</link>
      <description><![CDATA[TO PERMIT VERIFICATION OF DESIGN PARAMETERS AND ASSUMPTIONS GOVERNING "PREFLEX" BEAMS, FIELD TESTS WERE CONDUCTED ON A SKEWED SIMPLE-SPAN BRIDGE TO DETERMINE THE MAGNITUDE OF INITIAL AND LONG-TERM DEAD LOAD DEFLECTIONS, AND THE EXTENT OF CRACKING (IF ANY) IN THE PRECOMPRESSED CONCRETE. VERTICAL DEFLECTIONS OF THE BEAMS DURING CONTRUCTION AND UNDER SERVICE DEAD LOADS WERE COMPARED WITH THEORETICAL VALUES. ALTHOUGH THE MEASURED DEAD LOAD DEFLECTIONS WERE SLIGHTLY GREATER THAN DESIGN PREDICTIONS, THE STRUCTURE'S SHORT-TERM PERFORMANCE WAS FOUND TO BE SATISFACTORY. SURVEYS ARE TO CONTINUE FOR SIX YEARS SO THAT LONG-TERM DEFLECTION BEHAVIOR CAN BE EVALUATED. /FHWA/]]></description>
      <pubDate>Sat, 28 Jun 2003 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/102895</guid>
    </item>
    <item>
      <title>FIELD TESTING OF AN ORTHOTROPIC BRIDGE</title>
      <link>https://trid.trb.org/View/32118</link>
      <description><![CDATA[Field measurements of static live-load strains and deflections of an 88-ft 4-in. simple-span orthotropic- plate-deck bridge are compared with a theoretical analysis that represents the structure as a planar grid.  Design values based upon the AISC design manual are evaluated. Test results show that the planar-grid analysis method is a reliable analytical tool for predicting stresses and deflections.  Design procedures based upon the AISC manual give correct stress values at critical locations on the structure.  However, the design estimate of plate deflection is conservative. /FHWA/]]></description>
      <pubDate>Sat, 29 Mar 2003 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/32118</guid>
    </item>
    <item>
      <title>SIGN STRUCTURES UNDER WATCH</title>
      <link>https://trid.trb.org/View/576385</link>
      <description><![CDATA[Recent failures of traffic sign structures have caused states to strengthen their inspection procedures and develop sign structure management programs.  Many agencies have had to examine the question of responsibility for sign evaluation, inspection, and maintenance and in most cases, this task falls to the agency's bridge and structure section.  A sign-structure management program should include an inventory, inspection report, and maintenance program.  Each of these program components is addressed along with a description of the three main types of sign structures:  simple span structures, cantilever structures, and bridge-supported structures.  The article explains that the inspection of sign structures involves traffic control, access, inspection techniques, and reporting. On high-traffic, high-speed highways, the traffic control effort can be as challenging as the actual structure inspection.  Often inspectors must wait to close lanes to reach the structure in need of inspection.  It is emphasized that sign structures should be inspected by trained professionals who have an understanding of the load path through the structure and the particular types of defects which have been found or could be expected on these structures.  The article describes visual examination of structures, reporting systems for the inspection, and conversion of the data from the inspection into the basis for a maintenance program.]]></description>
      <pubDate>Fri, 05 Sep 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/576385</guid>
    </item>
    <item>
      <title>DURABILITY PERFORMANCES OF ALABAMA BRIDGE COMPONENTS AND SUBCOMPONENTS</title>
      <link>https://trid.trb.org/View/576342</link>
      <description><![CDATA[To gain a better understanding of how highway bridges in Alabama are performing in the area of durability/longevity, a review of the historical bridge records of the Alabama Department of Transportation was performed.  Because of the large number of bridges, it was decided to select the subset of old bridges that were replaced during the 1980-1993 period to evaluate their durability performance.  Based on an analysis of this data subset, the most structurally deficient major component was the deck, followed by the substructure.  The superstructure performed best.  The worst performing subcomponents were the wearing surface, deck structure, curbs, expansion joints, abutment wings, and abutment backwall.  The best performing subcomponents were drains, rivet/bolt/weld connections, and piers or bents.  The major reason for decks to fail functionally was the deck geometry.  However, the structural condition of decks at the time of functional obsolescence was also near failure.  The data indicated that simple span construction was superior to continuous span construction for enhancing durability.  Simple spans excelled in performance in every component and subcomponent except for the curbs, columns of the bents or piers, and the alignment of members.]]></description>
      <pubDate>Tue, 12 Aug 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/576342</guid>
    </item>
    <item>
      <title>RELIABILITY BASED BRIDGE INSPECTION</title>
      <link>https://trid.trb.org/View/483077</link>
      <description><![CDATA[A time-dependent reliability-based inspection procedure was developed to accurately determine the time interval between subsequent bridge inspections.  Through the use of the reliability index and numerical methods, a formula was developed and applied to simple span reinforced concrete T-beam bridges. Two factors were applied to the calculated resistance of the structure.  The first factor was applied to account for environmental conditions which cause material deterioration and subsequent strength reduction.  The second factor was developed in order to incorporate other forms of deterioration not directly related to environmental conditions, but equally as important in obtaining accurate assessments of structural resistance.  These additional indications of deterioration are observed during routine bridge inspections and recorded in the form of superstructure ratings.  Files from the NBI (National Bridge Inventory) containing Florida bridge inspection data were obtained and analyzed.  Application of a time-dependent reliability-based inspection procedure allows equipment and personnel, which may be tied up in unnecessary inspections, to be released resulting in a more efficient use of DOT (Department of Transportation) resources.]]></description>
      <pubDate>Tue, 20 May 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/483077</guid>
    </item>
    <item>
      <title>EXAMINATION OF BRIDGE LIVE LOAD MODEL IN KOREA</title>
      <link>https://trid.trb.org/View/483078</link>
      <description><![CDATA[Recently it has been reported in many countries, including Korea, that bridges have been seriously damaged due to the increasing volume of overloaded vehicles.  Since the safety of bridges is highly related to the design load level and extreme effects induced by traffic loads during their lifetime, it is important to determine the design live load to properly represent the load effect of the current truck traffic.  The live load depends on many parameters of truck and traffic characteristics.  The objective of this study was to calculate the maximum effect of truck loadings based on the survey data collected, and to evaluate the current live load model in Korean Bridge Design Code.  Several citation data were collected and two cases were considered: single truck and two trucks on the bridge.  The maximum live load effects for simple span and two equal continuous span bridges were calculated.  As a result of this study, the effect of live load models in the current design code is relatively low at very short spans and medium spans (about 40-50m).  Also, results show similar trends as the new live load model in AASHTO.]]></description>
      <pubDate>Tue, 20 May 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/483078</guid>
    </item>
    <item>
      <title>DYNAMIC BEHAVIOR OF SIMPLE-SPAN HIGHWAY BRIDGES</title>
      <link>https://trid.trb.org/View/105409</link>
      <description><![CDATA[RESULTS ARE PRESENTED OF AN ANALYTICAL STUDY OF THE DYNAMIC BEHAVIOR OF SIMPLE-SPAN HIGHWAY BRIDGES TRAVERSED BY HEAVY VEHICLES. THE FACTORS CONSIDERED INCLUDE THE SPEED OF THE VEHICLE, THE SPACING OF THE VEHICLE AXLES, THE DYNAMIC CONDITIONS OF THE BRIDGE AND THE VEHICLE AS THE VEHICLE ENTERS ON THE SPAN, AND THE UNEVENNESS OF THE BRIDGE SURFACE. REPRESENTATIVE BRIDGES AND VEHICLES WERE UTILIZED AND THE EFFECTS OF THE PARAMETERS ENUMERATED OBSERVED BY VARYING ONE PARAMETER AT A TIME. THE BRIDGES CONSIDERED ARE OF THE HIGHBEAM TYPE WITH SPAN LENGTHS IN THE RANGE BETWEEN 20 AND 78 FT. THIS TYPE OF BRIDGE CONSISTS OF A SERIES OF STEEL GIRDERS AND A REINFORCED CONCRETE SLAB. IN THE MARJORITY OF SOLUTIONS THE VEHICLE IS REPRESENTED AS A TWO- AXLE LOADING. THE MAGNITUDE OF THE MAXIMUM DYNAMIC EFFECTS IN A BRIDGE INCREASE WITH INCREASING VEHICLE SPEED. BY VARYING THE AXLE SPACING WHILE KEEPING ALL OTHER VARIABLES CONSTANT, IT WAS FOUND THAT A QUASI-RESONANCE CONDITION IS DEVELOPED WHEN THE TIME INTERVAL BETWEEN THE APPLICATION OF TWO AXLES OVER A POINT IS EQUAL TO THE FUNDAMENTAL NATURAL PERIOD OF VIBRATION OF THE BRIDGE. IF THE BRIDGE IS ALREADY IN A STATE OF OSCILLATION WHEN THE VEHICLE ENTERS THE SPAN, THE DYNAMIC EFFECTS PRODUCED BY THE VEHICLE DEPENDS ON THE TIMINING OF ITS ENTRY WITH THE OSCILLATION OF THE BRIDGE. THE INFLUENCE OF THE INITIAL VEHICLE OSCILLATION WAS INVESTIGATED BY CONSIDERING BOTH A BOUNCING AND A PITCHING MOTION FOR THE VEHICLE. THE MAGNITUDE OF THE RESULTING DYNAMIC EFFECTS WERE FOUND TO INCREASE ALMOST LINEARLY WITH THE AMPLITUDE OF THE INITIAL OSCILLATION CONSIDERED. RESULTS SHOW THAT ROADWAY UNEVENNESS MAY BE A SOURCE OF LARGE DYNAMIC EFFECTS IN HIGHWAY BRIDGES.]]></description>
      <pubDate>Fri, 09 Dec 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/105409</guid>
    </item>
    <item>
      <title>VIBRATION MEASUREMENTS ON SIMPLE-SPAN BRIDGES</title>
      <link>https://trid.trb.org/View/105470</link>
      <description><![CDATA[RESULTS ARE PRESENTED OF FIELD MEASUREMENTS OF DYNAMIC DEFLECTIONS OF SIMPLE-SPAN BRIDGES DUE TO THE PASSAGE OF A HEAVY VEHICLE. DATA ARE PRESENTED FOR FIVE BRIDGES OF TYPICAL DESIGN. NO STRAIN MEASUREMENTS ARE PRESENTED, AND THE DISCUSSION IS LIMITED TO A CONSIDERATION OF MIDSPAN DEFLECTIONS. TYPICAL DYNAMIC DEFLECTION RECORDS ARE SHOWN FOR THE FIVE BRIDGES TESTED. THE MAXIMUM OBSERVED AMPLITUDES OF VIBRATION FOR THE TEST BRIDGES VARY FROM 18 TO 40 PERCENT OF THE MAXIMUM STATIC DEFLECTION. THESE AMPLITUDES ARE CONSIDERABLY GREATER THAN WOULD BE PRODUCED BY A THEORETICAL SMOOTHLY RUNNING LOAD. THE FREQUENCIES OF THE OBSERVED VIBRATION WHILE THE LOAD IS ON THE SPAN IS GENERALLY NOT THE NATURAL FREQUENCY OF THE STRUCTURE BUT IS APPARANTLY RELATED TO THE NATURAL FREQUENCY OF THE VEHICLE ON ITS SUSPENSION SYSTEM. EXPERIMENTS WITH A VEHICLE IN WHICH THE SPRINGS HAD BEEN BLOCKED OUT OF ACTION INDICATE THAT CONSIDERABLY LARGER VIBRATIONS OCCUR IN THIS CASE THAN IN THE CASE OF A COMPLETELY SPRUNG VEHICLE. IT IS CONCLUDED THAT ONE OF THE MOST-IMPORTANT FACTORS WHICH INFLUENCE THE VIBRATION OF BRIDGES IS THE DYNAMIC CHARACTERISTICS OF THE VEHICLE ITSELF. ANOTHER IMPORTANT FACTOR IS THE CONDITION OF THE ROADWAY SURFACE ON THE APPROACHES, WHICH MAY CAUSE A VIBRATION OF THE VEHICLE MASS ON ITS SUSPENSION SYSTEM AS IT ENTERS THE SPAN. ALSO REPORTED ARE EXPERIMENTS WITH A VERTICAL ACCELEROMETER WHICH MAY BE USED TO MEASURE VIBRATIONS WITHOUT REFERENCE TO A FIXED POINT. THE USE OF AN ACCELEROMETER IS SHOWN TO BE A SATISFACTORY METHOD FOR MEASURING THE FREE VIBRATION OF A BRIDGE. /AUTHOR/]]></description>
      <pubDate>Fri, 09 Dec 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/105470</guid>
    </item>
    <item>
      <title>VIBRATION AND DEFLECTION OF ROLLED-BEAM AND PLATE-GIRDER BRIDGES</title>
      <link>https://trid.trb.org/View/105473</link>
      <description><![CDATA[OBSERVATIONS ARE REPORTED ON THE VIBRATION AND DEFLECTION CHARACTERISTICS ON AN EIGHT-SPAN PLATE GIRDER BRIDGE CONSISTING OF FIVE SIMPLE SPANS AND THREE SPANS OF CONTINUOUS BEAM DESIGN, AND A CONTINUATION OF THE VIBRATION AND DEFLECTION STUDIES ON THE FENNVILLE BRIDGE, WHICH WAS PREVIOUSLY REPORTED. THE LATTER BRIDGE CONSISTS OF SIX SIMPLE SPANS OF ROLLED BEAM CONSTRUCTION WITH CONCRETE DECKING. ONE OF THESE SPANS WAS BUILT WITH COMPOSITE CONSTRUCTION. THREE TYPES OF LOADING WERE USED--NORMAL COMMERCIAL TRUCK TRAFFIC WITH A MINIMUM OF CONTROL, CONTROLLED TESTING WITH TWO-AXLE TRUCKS, AND CONTROLLED TESTING WITH A SPECIAL THREE-AXLE TRUCK WITH AXLE SPACING IDENTICAL TO THAT FOR H20-S16 BRIDGE LOADING. OBSERVATIONS ARE REPORTED ON THE FREQUENCY OF VIBRATION, THE AMPLITUDE AND DURATION OF VIBRATION, AND THE DEFLECTION FOR THESE SPANS UNDER SIMILAR LOADING CONDITIONS. THE LATERAL DISTRIBUTION OF THE VIBRATION AND DEFLECTION AMONG THE LONGITUDINAL BEAMS IS SHOWN FOR SEVERAL ROLLED BEAM SPANS. A METHOD IS PRESENTED FOR CALCULATING THE NATURAL FREQUENCY OF A HIGHWAY SPAN WHICH CHECKS THE OBSERVATIONS WITHIN APPROXIMATELY THREE PERCENT. THE OCCURRENCE OF APPRECIABLE VIBRATION IS CORRELATED WITH THE TYPE, GROSS WEIGHT, AXLE SPACING, AND SPEED OF THE VEHICLE CAUSING VIBRATION. OTHER FACTORS INFLUENCING VIBRATION ARE DISCUSSED - FOR EXAMPLE, THE EFFECT OF VEHICLE SEQUENCE ON VIBRATIONS AND THE EFFECT OF INDUCED IMPACT. THE DIFFERENCES IN BEHAVIOR OF THE VARIOUS SPANS ARE CORRELATED WITH PRESENT DESIGN CRITERIA, THAT IS, DESIGN LIVE LOAD PLUS IMPACT DEFLECTION AND DEPTH TO SPAN LENGTH RATIOS. /AUTHOR/]]></description>
      <pubDate>Fri, 09 Dec 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/105473</guid>
    </item>
    <item>
      <title>GRAPHS FOR THE DIRECT SHEAR DESIGN OF PRESTRESSED CONCRETE MEMBERS</title>
      <link>https://trid.trb.org/View/105589</link>
      <description><![CDATA[A PRACTICAL DESIGN AID IS PRESENTED FOR STANDARD PRE- STRESSED CONCRETE MEMBERS PERMITTING ANY EXACT AND COMPLETE GRAPHICAL SHEAR DESIGN FOR ANY UNIFORMLY LOADED SIMPLE SPAN. THE GRAPHS OUTLINE VISUALLY THE SHEAR STEEL REQUIRED BY THE ACI BUILDING CODE SHEAR STEEL EQUATIONS. THE COMPUTER PROGRAM DEVELOPED TO EXECUTE THE CALCULATIONS AND DRAW THE GRAPHS IS GENERAL AND CAN BE APPLIED TO ANY PRESTRESSED MEMBER. /PCIJ/]]></description>
      <pubDate>Fri, 11 Nov 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/105589</guid>
    </item>
    <item>
      <title>RESPONSE OF HORIZONTALLY CURVED BRIDGE TO MOVING LOAD</title>
      <link>https://trid.trb.org/View/105480</link>
      <description><![CDATA[A METHOD OF ANALYSIS OF THE DYNAMIC RESPONSE OF A HORIZONTALLY CURVED SIMPLE-SPAN BRIDGE IS PRESENTED SUBJECTED TO A SMOOTHLY MOVING MASS LOAD. THE METHODS OF ANALYSIS FOR VIBRATION OF BRIDGES ON STRAIGHT ALIGNMENT INVOLVING MOVING MASS LOADS ARE REVIEWED. SOLUTION OF THE PRESENT PROBLEM THROUGH THE USE OF THE METHOD OF UNDETERMINED COEFFICIENTS IS DEMONSTRATED. A PARAMETRIC STUDY IS MADE OF THE EFFECTS OF HORIZONTAL CURVATURE, RIGIDITY RATIO, SPEED PARAMETER, WEIGHT RATIO AND FREQUENCY RATIO ON THE RESPONSE OF THE BRIDGE TO FLEXURAL AND TORSIONAL VIBRATIONS. THE EFFECTS OF THE FIRST' THREE PARAMETERS ON THE RESPONSE WITH THE MOVING MASS LOAD ARE NEARLY THE SAME AS THOSE WITH A CONSTANT MOVING FORCE, WHILE THOSE OF THE LATTER TWO PARAMETERS ARE ESSENTIALLY THE SAME AS THAT OF A STRAIGHT BRIDGE. /AUTHOR/]]></description>
      <pubDate>Fri, 04 Nov 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/105480</guid>
    </item>
    <item>
      <title>DYNAMIC TESTS ON A ROLLED-BEAM COMPOSITE SIMPLE SPAN BRIDGE</title>
      <link>https://trid.trb.org/View/101723</link>
      <description><![CDATA[THE REPORT DESCRIBES FIELD STUDIES CONDUCTED COOPERATIVELY BY THE STATE AND THE /THEN/ PHYSICAL RESEARCH DIVISION OF THE BUREAU OF PUBLIC ROADS. THE PRIMARY OBJECTIVE WAS TO MEASURE ACTUAL DYNAMIC AMPLIFICATION OF STRAIN AND DEFLECTION IN A TYPICAL SIMPLE SPAN COMPOSITE I-BEAM STRUCTURE AND TO COMPARE THE EXPERIMENTAL RESULTS WITH COMPUTED THEORETICAL AND DESIGN VALUES. STRAIN AND DEFLECTION GAGES WERE LOCATED AT CRITICAL POINTS ON THE BRIDGE. ACCURATELY WEIGHED AND MEASURED TEST VEHICLES WERE THEN DRIVEN ACROSS THE BRIDGE OVER A WIDE RANGE OF CONTROLLED SPEEDS AND LATERAL LANE POSITIONS WHILE DYNAMIC RESPONSES WERE BEING RECORDED. OF SIGNIFICANCE WERE THE HIGH AMPLIFICATIONS OF STRAIN AND DEFLECTION OBSERVED WHEN THE TEST VEHICLES PASSED THROUGH A DEPRESSION CREATED IN THE ROADWAY APPROACH TO THE SIMPLE SPAN THEREBY MEASURING THE ADVERSE EFFECT OF POOR MAINTENANCE ON SIMPLE SPAN APPROACHES. COMPARATIVELY HIGH STRAIN VALUES NOTED IN GENERAL ON THIS STRUCTURE MARK THE FINDINGS AS ESPECIALLY SIGNIFICANT FOR USE IN FUTURE STUDIES CORRELATING THE DYNAMIC RESPONSE OF SIMILAR STRUCTURES. THE FACT THAT TWO TEST VEHICLES OF WIDELY DIVERGENT CHARACTERISTICS WERE USED ON THIS STUDY ADDS MORE DEPTH TO THE STUDY. COMPARISONS OF THEORETICAL AND EXPERIMENTAL VALUES UNDER TWO MODES OF LOADING ARE MADE AND THE GOOD COMPARISONS IN EACH CASE LEND ADDED VALIDITY TO THE FINDINGS . /AUTHOR/]]></description>
      <pubDate>Sat, 01 Oct 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/101723</guid>
    </item>
    <item>
      <title>COMPUTER PROGRAM FOR ANALYSIS AND DESIGN OF SIMPLE-SPAN PRECAST PRESTRESSED HIGHWAY OR RAILWAY BRIDGES</title>
      <link>https://trid.trb.org/View/105475</link>
      <description><![CDATA[THE COMPUTER PROGRAM APPLIES TO EITHER HIGHWAY OR RAILROAD BRIDGES WITH VARIOUS TYPES OF PRESTRESSED UNITS ON SIMPLE SPANS, EITHER WITH OR WITHOUT A COMPOSITE DECK. BASED ON CONVENTIONAL DESIGN PROCEDURES, THE PROGRAM MECHANIZES ALL THE ROUTINE CALCULATIONS AND PROVIDES A SIZEABLE REDUCTION IN DESIGN TIME AND COST. THIS IS ONE OF A SERIES OF COMPUTER PROGRAMS BEING DEVELOPED BY THE PORTLAND CEMENT ASSOCIATION. THIS PROGRAM IS WRITTEN IN FORTRAN IV LANGUAGE FOR THE IBM 1130 COMPUTER. OUTPUT MAY BE BY A 1132 PRINTER OR A CONSOLE PRINTER. /AUTHOR/]]></description>
      <pubDate>Fri, 30 Sep 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/105475</guid>
    </item>
    <item>
      <title>FUNCTIONAL RELATIONSHIPS BETWEEN ACTUAL TRUCK AND AASHO DESIGN LOADINGS FOR SIMPLE SPAN BRIDGES</title>
      <link>https://trid.trb.org/View/102912</link>
      <description><![CDATA[THE MAXIMUM MOMENT AND SHEAR FORCE ARE USED AS A MEASURE OF OVERLOAD FOR SIMPLE SPAN BRIDGES. OVERLOAD FRACTIONS ARE DEFINED. THESE ARE RATIOS WHICH INDICATE THE AMOUNTS BY WHICH THE MAXIMUM DESIGN MOMENTS AND SHEARS /DEAD PLUS LIVE LOAD/ ARE CHANGED WHEN TRUCKS OF VARIOUS CONFIGURATIONS AND LOAD LIMITS CROSS SIMPLE SPAN BRIDGES. THE DESIGN LIVE LOADS CONSIDERED ARE THE AASHO H AND HS LOADING SCHEMES. FUNCTIONAL RELATIONSHIPS WHICH ALLOW THE SYSTEMATIC CALCULATION OF OVERLOAD ARE PRESENTED. THE CONCEPT OF CRITICAL SPAN LENGTH IS UTILIZED. THE EFFECTS OF TRUCKS ON THE MAGNITUDES OF MOMENTS AND SHEARS ARE GENERALIZED BY THE USE OF CERTAIN TRUCK PARAMETERS. /AUTHOR/]]></description>
      <pubDate>Tue, 23 Aug 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/102912</guid>
    </item>
    <item>
      <title>FORCED VIBRATION OF CONTINUOUS HIGHWAY BRIDGES</title>
      <link>https://trid.trb.org/View/105403</link>
      <description><![CDATA[A CORRELATION IS PRESENTED OF FORCED VIBRATION THEORY WITH DYNAMIC IMPACT TESTS FOR THREE CONTINUOUS HIGHWAY BRIDGES AND A SIMPLE SPAN HIGHWAY BRIDGE. THE EXPERIMENTAL IMPACT WAS DETERMINED AT THE CENTERLINE OF THE SINGLE SPAN HIGHWAY BRIDGE AND IN THE OUTER AND INNER SPANS AND AT THE INTERIOR SUPPORTS FOR THE THREE TYPES OF CONTINUOUS FOUR-SPAN HIGHWAY BRIDGES. THE EFFECT OF THE VEHICLE IS ASSUMED TO BE AN OSCILLATING FORCING FUNCTION WHOSE FREQUENCY IS THE FREQUENCY OF AXLE REPETITION AND WHOSE FORCE IS THE OSCILLATING LOAD EFFECT OF A CONSTANT FORCE TRAVERSING A BEAM. THE CORRELATION OF THE THEORETICAL AND EXPERIMENTAL IMPACT INDICATES THAT THE SIMPLIFICATIONS MADE IN THE EFFECT OF THE VEHICLES ARE JUSTIFIED FOR THE BRIDGES TESTED AND THE EXPERIMENTAL VEHICLE VELOCITIES USED. THESE RESULTS SHOW QUALITATIVELY THAT THE AMOUNT OF IMPACT IS A FUNCTION OF THE RATIO OF THE FREQUENCY OF AXLE REPETITION TO THE LOADED NATURAL FREQUENCY OF THE STRUCTURE. /AUTHOR/]]></description>
      <pubDate>Fri, 05 Aug 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/105403</guid>
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