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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>
    <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>
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    <item>
      <title>PERFORATED BEAM TEST FOR DETERMINING TENSILE STRENGTH OF ROCK</title>
      <link>https://trid.trb.org/View/121334</link>
      <description><![CDATA[THE PERFORATED BEAM TEST IS INVESTIGATED AS AN ALTERNATIVE METHOD FOR DETERMINING THE TENSILE STRENGTH OF ROCK. A SERIES OF FOUR-POINT BENDING TESTS TO FRACTURE WERE CARRIED OUT WITH LIMESTONE BEAMS HAVING THE SAME OVERALL DIMENSIONS BUT WITH CENTRAL TRANSVERSE HOLES OF VARYING DIAMETER. THE RESULTS ARE INTERPRETED BY TAKING INTO ACCOUNT THE STRESS CONCENTRATION EFFECTS AS FOUND BY THEORY AND PHOTOELASTIC ANALYSIS. IT IS CONCLUDED THAT THIS TYPE OF TEST HAS A NUMBER OF ADVANTAGES OVER OTHER INDIRECT METHODS BUT, AS IN THE LATTER, BECAUSE OF NON-UNIFORM STRESS DISTRIBUTION AT FRACTURE, IT CANNOT FURNISH UNIQUE INFORMATION ON THE TENSILE STRENGTH OF ROCK WITHOUT A DETAILED KNOWLEDGE ON THE STRESS-STRAIN BEHAVIOR OF THE MATERIAL UP TO FRACTURE. /AUTHOR/]]></description>
      <pubDate>Sun, 15 Aug 2004 02:38:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/121334</guid>
    </item>
    <item>
      <title>EVALUATION OF SEISMIC INSTRUMENTS AND BASIC RESEARCH ON SEISMIC WAVE PROPAGATION</title>
      <link>https://trid.trb.org/View/119008</link>
      <description><![CDATA[FACILITIES FOR TESTING SEISMIC INSTRUMENTATION OF INTEREST TO TSL, AFCRL WERE DEVELOPED. A MEASURING PROGRAM, USING DYNAMIC PHOTOVISCOELASTIC METHODS, WAS CONDUCTED WITH THE AIM OF DETERMINING THE COMPLETE RHEO-OPTICAL CHARACTERIZATION OF HYSOL, /A URETHANE RUBBER COMPOUND/. A DATA ANALYSIS CENTER, CAPABLE OF SOPHISTICATED ANALYSIS OF SEISMIC DATA WAS ASSEMBLED. A PRELIMINARY INVESTIGATION OF THE TIME-AND SPACE-STATIONARY STATISTICAL CHARACTERISTICS OF SEISMIC NOISE WAS MADE. THREE COMPLETE SEISMIC INSTRUMENTATION PACKAGES FOR USE IN SEISMIC FIELD STUDIES WERE CONSTRUCTED. SOME FEATURES OF THE SEISMICITY AND THE CRUSTAL STRUCTURE OF NEW ENGLAND WERE INVESTIGATED. PHOTOELASTIC STUDIES OF EARLY STAGES OF THE BRITTLE SHEAR FRACTURE PROCESS WERE CONDUCTED UNDER THE CONDITION OF UNIAXIAL COMPRESSION. ANALYSIS WAS FOCUSED ON INITIAL STAGES OF CRACK GROWTH COALESCENCE WITHIN VARIOUS MODELED ARRAYS OF CRACKS. CRACK GROWTH BEGINS WELL BELOW THE ULTIMATE FRACTURE STRENGTH, AND IT ALSO BEGINS CONSIDERABLY BELOW THE CRACK- GROWTH STRESS PREDICTED BY GRIFFITH THEORY. OF THE POSSIBLE AN ECHELON ARRAYS OF PARALLEL GRIFFITH CRACKS, CERTAIN ARRAYS OPTIMAL FOR EARLY CRACK GROWTH ARE ORIENTED AT ABOUT 45 DEGREES TO THE APPLIED STRESS AXIS, IN CONTRAST TO THE 30 DEGREES ORIENTATION PREDICTED BY GRIFFITH THEORY. CRACK COALESCENCE WAS NOT FOUND TO OCCUR UNTIL DISTINCTLY LATER STAGES OF THE FRACTURE PROCESS. INITIAL STAGES OF CRACK GROWTH ARE CHARACTERIZED BY GROWTH PROCESS. INITIAL STAGES OF CRACK GROWTH ARE CHARACTERIZED BY GROWTH OF FLAWS INTO STABLE POSITION WITH RESPECT TO STRESS REQUIRED TO INITIATE CRACK GROWTH, DESPITE CLOSE PROXIMITY OF NEIGHBORING FLAWS. EMITTED SEISMIC PULSES ACCOMPANY EACH OF THE INITIAL CRACK- GROWTH STAGES, AND APPRECIABLE INCREASES IN APPLIED STRESS ARE REQUIRED TO ENFORCE FURTHER CRACK GROWTH. THESE RESULTS ARE GIVEN SIGNIFICANT SUPPORT BY RECENTLY REPORTED ROCK DEFORMATION STUDIES, AND THEY POSSIBLY EXPLAIN THE OCCURRENCE OF SOME OF THE MICROSEISMIC AND FORESHOCK ACTIVITY OBSERVED IN EARTHQUAKE PHENOMENA. /AUTHOR/]]></description>
      <pubDate>Sun, 15 Aug 2004 02:09:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/119008</guid>
    </item>
    <item>
      <title>PHOTOELASTIC DETERMINATION OF CONTACT STRESSES OF FOUNDATIONS. TECHNICAL NOTES</title>
      <link>https://trid.trb.org/View/481870</link>
      <description><![CDATA[The contact stress distribution underneath foundations under operating loads is important for a realistic estimation of settlements.  A series of model tests using a photoelastic model of a rigid foundation resting on sand were conducted at Queen's University, Belfast, Northern Ireland, to determine contact stresses underneath a rigid foundation.  Models were tested for centrally and eccentrically applied loads at different load levels. It was found that the stress distribution for central loading was bell shaped, with zero corner stresses for small and nonzero contact stresses for higher loads.  For eccentrically loaded foundations, the stress distribution was again bell shaped, whereby the effective width of the foundation was reduced.  The photoelastic method was found a valuable tool for analyzing this nonlinear contact problem.]]></description>
      <pubDate>Fri, 04 Apr 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/481870</guid>
    </item>
    <item>
      <title>EFFECTS OF SPECIMEN LENGTH ON LABORATORY BEHAVIOR OF SEALANTS</title>
      <link>https://trid.trb.org/View/110060</link>
      <description><![CDATA[TO PROVIDE THE MAXIMUM DEGREE OF PREDICTABILITY OF A PRODUCT, THE LABORATORY TESTING ENVIRONMENT SHOULD APPROACH SERVICE CONDITIONS AS CLOSELY AS PRACTICABLE. CURRENT PRACTICE IN THE TESTING OF SEALANTS IS TO USE A 2-IN. LONG SPECIMEN. HOWEVER, A SEALANT IN USE MAY BE AS LONG AS 40 FT. SPECIMEN LENGTHS OF 2, 4, AND 6 IN. ARE USED TO SHOW VARIATION IN TEST RESULTS WITH LENGTH. ASSUMING THE SEALANT TO BE A PERFECTLY ELASTIC MATERIAL, STRESSES IN THE SEALANT ARE COMPUTED MATHEMATICALLY. EXPERIMENTAL VALUES OF SPECIMENS WITH END NECKDOWN ARE USED. VALUES OF MODULUS AND ULTIMATE STRAIN ARE MEASURED. A QUALITATIVE EVALUATION OF THE SEALANT STRESSES IS SHOWN BY PHOTOELASTIC PICTURES. /AUTHOR/]]></description>
      <pubDate>Mon, 12 Dec 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/110060</guid>
    </item>
    <item>
      <title>DISCUSSION OF BODY-FORCE STRESSES IN GRAVITY STRUCTURES</title>
      <link>https://trid.trb.org/View/127321</link>
      <description><![CDATA[THE AUTHORS PRESENTED USEFUL RESULTS OF EXPERIMENTS ON THE DETERMINATION OF STRESS IN GRAVITY STRUCTURES USING PHOTOELASTIC ANALYSIS. HOWEVER, CERTAIN FEATURES OF THE ANALYSIS DESCRIBED CAST DOUBT ON THE VALIDITY OF THE ANALYTICAL RESULTS. AMONG THESE ARE: (1) THE RESULTS FOR STRESS DISTRIBUTION GIVEN BY AN EQUATION ARE ESSENTIALLY SIMILAR TO THOSE GIVEN BY LEVY, HOWEVER, THE LINEARITY OF THE RESULTING STRESS DISTRIBUTION DOES NOT RESULT FROM LEVY'S ANALYSIS, BUT IS ONE OF HIS INITIAL ASSUMPTIONS, (2) THE STRESS FUNCTION DEFINED MAY BE VALID FOR PLANE STRESS, OR FOR INCOMPRESSIBLE MATERIALS UNDER PLANE STRAIN CONDITIONS, HOWEVER, THE STRESS FUNCTION DOES NOT APPEAR GENERALLY COMPLETE FOR MATERIALS WITH POISSON'S RATIO LESS THAN 1/2 AND PLANE STRAIN CONDITIONS. THE STRESS FUNCTION SHOULD INCLUDE A TERM INCORPORATING POISSON'S RATIO. FIGURES ARE PRESENTED ON THE DISTRIBUTION OF VERTICAL NORMAL STRESS AND A COMPARISON OF ANALYTICAL AND EXPERIMENTAL DETERMINATION OF PRINCIPAL STRESS ON UPSTREAM FACE OF ELASTIC EARTH DAM. IT IS SUGGESTED THAT THE AUTHORS MAY WISH TO RECONSIDER THEIR CONCLUSIONS CONCERNING THE CURRENT STATE OF ANALYTICAL THEORY, AND THE APPLICABILITY OF EXISTING THEORY TO THE SOLUTION F PRACTICAL PROBLEMS. REFERENCES: BODY-FORCE STRESSES IN GRAVITY STRUCTURES, ROWLAND RICHARDS, JR. AND WERNER E. SCHMID, ASCE (PROC. PAPER 5749), JANUARY, 1968.]]></description>
      <pubDate>Thu, 29 Sep 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/127321</guid>
    </item>
    <item>
      <title>A PHOTOELASTIC - MODEL STUDY OF STRESS DISTRIBUTION AND ROCK FRACTURE AROUND MINING EXCAVATIONS</title>
      <link>https://trid.trb.org/View/124002</link>
      <description><![CDATA[A THREE-DIMENSIONAL PHOTOELASTIC-MODEL STUDY OF TWO HORIZONTAL MINING EXCAVATIONS WITH A CENTRAL PILLAR IS DESCRIBED. DETAILS OF EXPERIMENTAL TECHNIQUES ARE GIVEN AND STRESS DISTRIBUTIONS, ROCK-FRACTURE INITIATION ZONES AND THE DIRECTIONS OF SUBSEQUENT FRACTURE PROPAGATION AROUND THESE EXCAVATIONS ARE DETERMINED. IT IS SHOWN THAT THE TECHNIQUES ADOPTED FOR THIS INVESTIGATION OFFER REALISTIC MEANS FOR COMPARATIVE DESIGN STUDIES OF BEST SHAPE AND LAYOUT OF MINING EXCAVATIONS. /AUTHOR/]]></description>
      <pubDate>Thu, 05 May 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/124002</guid>
    </item>
    <item>
      <title>THEORETICAL AND EXPERIMENTAL STUDY OF HIGHWAY SKEW SLAB- BRIDGES</title>
      <link>https://trid.trb.org/View/98035</link>
      <description><![CDATA[FINITE DIFFERENCE EQUATIONS FOR A SYSTEM OF OBLIQUE COORDINATES WERE DEVELOPED TO ANALYSE STRESSES IN SKEWED PLATES BY COMPUTERS. THE ANALYSIS IS SUITABLE FOR ANY SKEW ANGLE AND ANY RATIO OF LENGTH TO WIDTH. LABORATORY PHOTO- STRESS STUDIES OF THREE SCALE MODELS WERE CARRIED OUT IN CONJUNCTION WITH THE MATHEMATICAL STUDY. THE RESULTS INDICATE THAT QUALITATIVELY, THE ANALYSIS REPRODUCES THE GENERAL BEHAVIOR OF SKEWED PLATES. THE AUTHORS ARE CONTINUING THE RESEARCH TO INVESTIGATE THE CASE OF A PLATE HAVING A RIGID BEAM ALONG ITS FREE EDGE CORRESPONDING TO A BRIDGE HAVING CURBS. /CGRA/]]></description>
      <pubDate>Mon, 24 Jan 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/98035</guid>
    </item>
    <item>
      <title>A PHOTOELASTIC INVESTIGATION OF ANCHORAGE BEARING STRESSES</title>
      <link>https://trid.trb.org/View/211468</link>
      <description><![CDATA[This investigation focuses on a number of features which have hitherto been less researched but which have been found to be critical in the behaviour and failure mechanism of anchorage zones.  These include the mode of load transfer, the proximity of the anchorage unit to the surface plane and the critical role of the high sub-surface shear in the immediate vicinity of the anchorage unit.  The results show the significant advantages of the embedded anchorage over the corresponding external unit and the critical dependence of the surface stresses upon the proximity of the anchorage unit.  In a typical multi-anchorage endblock, the behaviour of adjacent units is found to be sensibly independent. (Author/TRRL)]]></description>
      <pubDate>Sun, 30 Jun 1985 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/211468</guid>
    </item>
    <item>
      <title>PHOTOELASTIC ANALYSIS OF DIRECT SHEAR TESTS FOR GRANULAR MATERIALS</title>
      <link>https://trid.trb.org/View/203588</link>
      <description><![CDATA[This paper describes tests performed in a direct shear box on an optically sensitive model granular material consisting of particles of crushed glass.  The use of polarized light allows determination of principal stress trajectories inside the mass of particles, and on the shear plane in particular. The corresponding displacement increments field was measured by means of stereophotogrammetry.  Test results were compared with theoretical solutions based on rigid-plastic and elastic models for the sheared material.  It is shown that close agreement is obtained when plastic solution or classical Coulomb's sliding hypothesis is assumed.  (TRRL)]]></description>
      <pubDate>Mon, 30 Jul 1984 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/203588</guid>
    </item>
    <item>
      <title>PHOTOELASTIC MODEL STUDIES FOR AN EXPERIMENTAL SEGMENTAL BRIDGE</title>
      <link>https://trid.trb.org/View/185753</link>
      <description><![CDATA[The Pennsylvania Department of Transportation designed an experimental segmental bridge which was constructed at the Pennsylvania Transportation Research Facility at The Pennsylvania State University.  To supplement the data obtained from field testing the bridge and from laboratory testing of segments, a photoelastic model study was conducted.  The objectives of the photoelastic model studies were to determine the stress distribution in segments in the area between the diagonal tendon termination points and to show that the scattered light photoelastic technique can be used for complex three-dimensional problems.  A 1/15 scale model of a segment was studied using the scattered light technique.  The model was cast from a photoelastic epoxy and did not include steel reinforcing.  Cantilever flanges were not included, but ducts for diagonal tendons were cast into the model.  A steel loading frame was designed to apply stresses to the model.  The model was investigated using a scattered light polariscope.  Stresses were determined in regions away from the influence of the diagonal tendons and in the regions surrounding the diagonal tendons.  The scattered light photoelastic technique was successfully used to determine the stresses present within these regions of the web.  Stress concentrations developed by the anchored diagonal tendons were found to be localized and not of extreme magnitudes.  A major limitation of the scattered light technique was seen in the rotation of the principal stress axes in the region near the diagonal tendon. Overall, the scattered light technique was shown to have advantages over the alternative frozen stress approach. (FHWA)]]></description>
      <pubDate>Thu, 30 Jun 1983 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/185753</guid>
    </item>
    <item>
      <title>A 3-D PHOTOELASTIC MODEL INVESTIGATION OF THE Y-JUNCTION OF THE CITY CIRCLE AND CLIFTON HILL TUNNELS</title>
      <link>https://trid.trb.org/View/171013</link>
      <description><![CDATA[The distribution of stresses around the y- junction of two tunnels of the Melbourne underground rail loop was investigated using three- dimensional photoelastic models. The results are compared with those obtained from two- dimensional photoelastic models and from two- dimensional analytical solutions.  A novel room- temperature method of three- dimensional photoelastic modelling called the "residual creep method" was used, in addition to the conventional "frozen stress" method.  This new method allowed the use of heterogeneous materials, so that a concrete pillar at the y- junction could be simulated, and the results compared with those from the homogeneous frozen stress model (A). (TRRL)]]></description>
      <pubDate>Tue, 30 Mar 1982 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/171013</guid>
    </item>
    <item>
      <title>SHEAR DEVICES FOR DETERMINING DYNAMIC SOIL PROPERTIES</title>
      <link>https://trid.trb.org/View/78917</link>
      <description><![CDATA[This paper examines the state of the specimen in some of the more popular shearing devices used for dynamic (as well as for static) soil testing.  The conditions prevailing in the hollow cylinders used by Ishihara, Lade, and Sherif are briefly discussed and compared; the importance of the proper ratio between height and thickness and height and mean diameter is emphasized.  A relatively detailed study of the simple shear devices of the Roscoe type and of the NGI type is made; both being extensively used in cyclic strength research.  The results of a three-dimensional photoelastic study based on the frozen stress technique are presented and compared to those obtained from published finite element analyses.  They show that the claim regarding the uniformity of the shearing stresses on the central plane in the NGI device is totally unwarranted; the conditions being slightly more acceptable in the Roscoe device.  Recommendations are made regarding the conditions to be satisfied by testing machines to avoid undersirable end effects. /Author/]]></description>
      <pubDate>Thu, 12 Oct 1978 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/78917</guid>
    </item>
    <item>
      <title>STRESSES IN SHALLOW ELLIPTICAL TUNNEL</title>
      <link>https://trid.trb.org/View/66603</link>
      <description><![CDATA[A simple 3-dimensional photoelastic model test was devised that would yield data which is compatible with previously reported unlined elliptical tunnel under line loading.  The details are outlined of the three-dimensional photoelastic stress freezing tests that were performed on lightly loaded models in a controlled circulation oven.  The studies found that under the action of a concentrated surface load, only a relatively small region of the upper portion of the tunnel is subject to high tensile hoop stresses while the compression hoop stresses are distributed more uniformly with their maximum values at about 45 deg. on both sides of the vertical semi axis.  In addition to obvious differences because of the attenuation of the concentrated load effect away from the point of load application, the distribution of hoop stresses in the section directly under the loading was also shown to differ significantly.  It is concluded that the stress distribution found from a 2-dimensional physical or numericalmodel under an assumed line loading, can only give a coarse approximation of the true effect of a concentrated point load.]]></description>
      <pubDate>Tue, 15 Mar 1977 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/66603</guid>
    </item>
    <item>
      <title>CRACKING OF FRESH CONCRETE AS RELATED TO REINFORCEMENT</title>
      <link>https://trid.trb.org/View/33958</link>
      <description><![CDATA[The research reported here was undertaken to quantify the effect of depth of cover and two other variables, concrete slump and reinforcement bar size, on the tendency to produce the subsidence cracks over the reinforcement that lead to corrosion of the reinforcement in concrete bridge decks.  A photoelastic study was also undertaken to determine the magnitudes of the tensile stresses above the reinforcement as a function of depth of cover.  Finally, a corrosion study was carried out to verify that subsidence cracking over the reinforcement leads to corrosion of the reinforcement in the presence of deicing salts.  The conclusions from this study were: depth of cover significantly affects subsidence cracking, corrosion potentials are significantly higher for cracked concrete, and tensile stresses over reinforcing bars due to body stresses in fresh concrete increase sharply with decreasing cover.]]></description>
      <pubDate>Wed, 05 Nov 1975 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/33958</guid>
    </item>
    <item>
      <title>PHOTOELASTIC STUDY OF WAVE PROPAGATION AROUND EMBEDDED STRUCTURAL ELEMENTS</title>
      <link>https://trid.trb.org/View/140035</link>
      <description><![CDATA[Photoelastic methods have been used extensively it recent years to determine stress distributions associated with a propagating stress wave.  In this paper a series of studies are described which have been conducted to determine stresses in the free field of a two-dimensional plate and of the boundaries of embedded structural elements in the plate during passage of a stress wave.  Both explosives and traveling air shocks were used to generate the stress waves. Results for circular holes and rigid circular inclusions are presented and compared with equivalent static stresses based on the free field conditions.  Important conclusions are drawn regarding dynamic stress concentration factors. /Author/]]></description>
      <pubDate>Thu, 16 Jan 1975 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/140035</guid>
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