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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>Efficiency and performance of diamond grinding in Texas</title>
      <link>https://trid.trb.org/View/1327231</link>
      <description><![CDATA[The paper presents the results of a study to quantify the deterioration of a diamond ground continuously reinforced concrete pavement (CRCP) surface in terms of macrotexture, skid-resistance, ride quality and pavement noise over time. The influence of site specific features such as traffic speed and load, pre-texturing prior to the grinding operation, lane, wheel path and trafficking direction on the deterioration of the surface properties is investigated. The four surface properties were measured immediately after the grinding operation and at three subsequent time intervals after 4, 9 and 15 months. Panel data analysis incorporating fixed effects is implemented to evaluate the significance of the site specific features on the deterioration of the surface properties. A significant reduction in macro-texture and skid resistance was apparent. An increase in noise was evident soon after grinding. No significant change in roughness was found. The changes in the surface properties appear to be related to traffic over time but do not appear to be influenced by the pre-existing texturing prior to grinding. Additional monitoring of the sections is recommended to better characterize the long-term benefits of diamond grinding as a rehabilitation strategy for CRCP>]]></description>
      <pubDate>Tue, 14 Oct 2014 12:15:04 GMT</pubDate>
      <guid>https://trid.trb.org/View/1327231</guid>
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      <title>Early-Life, Long-Term, and Seasonal Variations in Skid Resistance in Flexible and Rigid Pavements</title>
      <link>https://trid.trb.org/View/881664</link>
      <description><![CDATA[Skidding contributes to up to 35% of wet weather accidents. Increased temperature and surface wear and polishing may affect the available friction and further increase skid-related accidents. Several studies have attempted to examine and quantify these variations mostly with inadequate or inappropriate conclusions. The surface friction of both portland cement concrete (PCC) and asphalt concrete (AC) pavements was measured monthly to determine the influencing factors and quantify the seasonal fluctuation. Skid number (SN) and pertinent data of the Long-Term Pavement Performance program were obtained for both PCC and AC pavements, incorporating all geographic and climatic regions of the United States and Canada, to determine the contributing factors and quantify the long-term and early-life variations of surface friction. Surface friction was shown to fluctuate as a result of ambient or pavement temperature fluctuation at 0.35 British pendulum number per 18°C change in temperature. The effect of prior weather was shown to be insignificant. Following construction, AC and PCC surface friction was shown to increase by 5 SN in about 18 months and 4 SN in about 2½ years. Skid resistance was shown to decrease thereafter at 0.27 SN for AC and at 0.24 SN for PCC pavements per million vehicle passes. Cumulative traffic passes, pavement age, speed, and temperature during the testing and PCC pavement surface texture types were found to be statistically significant for the prediction of long-term surface friction. AC pavement long-term surface friction was shown to be more sensitive, as compared with PCC, to predominant climatic condition.]]></description>
      <pubDate>Thu, 26 Mar 2009 09:05:22 GMT</pubDate>
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      <title>OUT OF THE SKID PAN...</title>
      <link>https://trid.trb.org/View/674880</link>
      <description><![CDATA[Road surface texture plays a vital part in preventing skidding and saving lives, but its science is subtle. For pedestrians, a loss of friction is not normally a problem, except for very smooth surfaces. Selecting and installing a suitable surfacing material is important, and depends on expert design, specifications, and installation supervision. For wheeled vehicles, the road surface texture needs to be defined better, by allowing for both microtexture and macrotexture. Microtexture is the principal component in low-speed friction, and is measured by the polished stone value (PSV) test and, on the road, by the SCRIM, Grip-tester, or pendulum. Macrotexture, also known as 'texture depth', is the principal component of high-speed skid resistance, and contributes to low-speed skid resistance. In both dry and wet weather, the tyre is deformed by the texture, absorbing energy and generating friction. Both microtexture and macrotexture change and become less effective with the passage of time, and need to be monitored to reduce accident risk. The UK road network's high safety is partly due to the skid resistance policy of the Highways Agency (HA), based on work of the former Transport and Road Research Laboratory (TRRL) between 1955 and 1980. The resulting design guidance, and its later updates, are given in Volume 7 of the Design Manual for Roads and Bridges.]]></description>
      <pubDate>Wed, 07 Feb 2001 00:00:00 GMT</pubDate>
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      <title>PAVEMENT TEXTURE AND SKID RESISTANCE MODELS FOR NEW ZEALAND CHIPSEALED PAVEMENTS</title>
      <link>https://trid.trb.org/View/499454</link>
      <description><![CDATA[Robust models are required by pavement asset managers to predict the change in friction of the network with time in order to optimise maintenance activities.  Models are also required by the pavement designer so that friction characteristics of different surface treatments can be compared.  A major step in standardising skid resistance measurement was undertaken by the PIARC Technical Committee on Surface Characteristics through the International Experiment to Compare and Harmonise Texture and Skid Resistance Measurement in 1995.  The overall objectives of the experiment were to compare the many different measuring methods used around the world and to develop relationships for converting results produced by the different devices to a common scale, the International Friction Index (IFI).  As a result, international standardisation and harmonisation is now possible, leading to the development of predictive models.  To be useful for pavement management purposes, these models must predict the change of friction with time and the friction requirements for different traffic conditions.  Proposed models for use on New Zealand chipseals are discussed in this paper.  These models have been derived from previously published information and New Zealand specific research programmes. (a) For the covering entry of this conference, please see IRRD 895316.]]></description>
      <pubDate>Tue, 06 Apr 1999 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/499454</guid>
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    <item>
      <title>NORMALIZED PERCENT SKID GRADIENT ALGORITHM FOR COMPUTING THE SPEED DEPENDENCE OF SKID NUMBER, COMPUTER PROGRAM DOCUMENTATION</title>
      <link>https://trid.trb.org/View/84671</link>
      <description><![CDATA[The normalized percent skid gradient program addresses the problem of assessing the change of skid number with respect to speed.  The program uses skid number, measured at a single speed, in conjunction with a pavement texture measurement as the basis for determining skid numbers at various other speeds.  Thus the program provides field personnel, who are responsible for collecting and maintaining inventories of skid number data, a means of reducing skid resistance testing from measurements at two or more speeds to testing at a single speed and collection of a pavement texture measurement.  The specific function of the program is to provide skid number estimates at up to three additional speeds based on skid information at one speed together with a texture measurement. At present this is set up for bituminous pavements surveyed during the course of this study.  In order to generalize the program's capability to other bases of pavement friction data and texture measurements, a number of supporting capabilities for data reduction, regression and correlation analyses, including evaluation of texture descriptors from profile data are available to the user.  /FHWA/]]></description>
      <pubDate>Sat, 26 May 1979 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/84671</guid>
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      <title>ASPHALT SURFACINGS WITH MODIFIED TEXTURE</title>
      <link>https://trid.trb.org/View/72861</link>
      <description><![CDATA[This report contains the results of the work carried out by the working Committee B9; Asphalt Surfacings with Modified Texture.  Most of the research done by the working committee was concentrated on actual test sections of highways in the Netherlands.  Three types of asphalt mixes were studied under traffic, namely hot rolled asphalt with precoated chippings (according to the English procedure), the so called open asphalt, normally used as a binder course and thirdly the most promising new development, porous asphalt having approximately 20% voids.  The working committee came to the following conclusions and recommendations: (1) the dressing of fine dense asphalt with precoated chippings of 12-15 mm can produce good results only with very careful workmanship under favourable conditions.  (2) porous asphalt (high pervious open-textured asphalt) can be used for reducing the thickness of the film of water on the road surface and for achieving good skidding resistance at high speeds.  The low-speed skidding resistance of this material would have to be further improved.  (3) as a provisional measure, short-term improvement of the surface properties of bituminous mixes can be achieved by the use of open-textured asphalt.  This was already common practice with the Rijkswaterstaat, because construction in stages was applied. (4) in course of time it may be possible to develop a mix composition that can be applied directly to the roadbase & can be characterized as "coarse asphalt".  The open-textured asphalt with a composition conforming to the 1972 specifications for road-building materials can already perform such a function, though its service life is often less than that of dense coarse-graded asphalt (5 to 10 years).  (5) more research into the applicability of plant mix seals under Netherlands conditions will have to be carried out. /TRRL/]]></description>
      <pubDate>Wed, 28 Jun 1978 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/72861</guid>
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    <item>
      <title>TYRE/ROAD SURFACE INTERACTION</title>
      <link>https://trid.trb.org/View/67055</link>
      <description><![CDATA[Skid resistance, the change in wet skid resistance with speed, tyre abrasion, tyre to road noise and riding comfort are all facets of tyre/road interaction which are either dominated, or very greatly influenced, by the texture of the road surface.  The long-established concepts of microtexture and macrotexture have been further investigated.  New techniques for the study of aggregate microtexture by means of the scanning electron microscope have been initiated.  A new theory to account for the drainage characteristics of road surface macrotexture has also been formulated, together with a new method for determining these drainage characteristics by outflow meter and relating outflow time to the friction versus speed relationship; a new method of mix design for the formulation of a range of high friction dense asphalts (these have been manufactured and sold under the name 'delugrip") and pavement concretes, incorporating the findings of the above studies, has been developed.  The paper outlines the main features of some of these studies and gives reference to others, relating them to further studies which have been carried out and to alternative methods of test and design which exist in this field of investigation. Results from surfacings which have been manufactured and laid in accordance with the principles presented are given. /TRRL/]]></description>
      <pubDate>Sat, 02 Jul 1977 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/67055</guid>
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    <item>
      <title>CALIFORNIA SKID RESISTANCE STUDIES</title>
      <link>https://trid.trb.org/View/135671</link>
      <description><![CDATA[A correlation between skid test values and surface texture measurements was attempted.  The Modified Sand Patch test exhibited poor correlation and poor repeatability.  The Outflow Meter test exhibited fair-to-good correlation with high-speed skid numbers on PCC pavements, and this test showed good to excellent repeatability.  Further testing and evaluation is recommended in order to establish Outflow Meter requirements for the surface texture of new PCC pavements.  None of the texture measuring methods correlated with Skid Number Gradients.  Coefficient of friction measurements were taken for the entire width of PCC traffic lanes.  The coefficient of friction on the wheel tracks was found to be substantially lower than that for the rest of the lane width, indicating that localized polishing of the traffic lanes in the wheel tracks is a typical occurrence on PCC pavements.  The rightmost (truck) lanes are subjected to a greater polishing action on the wheel tracks than the wheel tracks in the adjacent lanes.  A small-scale laboratory wear-and-polishing device proved to be unsuccessful.  Before-and-after studies of a pavement overlaid with calcinced bauxite chip seal showed a dramatic increase in skid numbers, but no significant change in the accident frequency. /FHWA/]]></description>
      <pubDate>Thu, 05 Sep 1974 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/135671</guid>
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    <item>
      <title>METHODS OF TEXTURING NEW CONCRETE ROAD SURFACES TO PROVIDE ADEQUATE SKIDDING RESISTANCE</title>
      <link>https://trid.trb.org/View/100866</link>
      <description><![CDATA[THE DEVELOPMENT OF VARIOUS METHODS FOR TEXTURING THE FRESH SURFACE OF HIGH SPEED CONCRETE ROADS IS DISCUSSED. THE PERFORMANCE IS REVIEWED OF VARIOUS ROADS INCLUDING THOSE TEXTURED BY THE TYPE OF WIRE BROOM SPECIFIED IN THE CURRENT MINISTRY OF TRANSPORT SPECIFICATION FOR ROAD AND BRIDGE WORKS. THE RATE OF WEAR AND THE SKIDDING RESISTANCE OF SLOW AND FAST LANE SURFACES ARE EXAMINED. AN EXAMINATION IS ALSO MADE OF THE EFFECT OF THE INITIAL TEXTURE IMPOSED ON THE RATE OF CHANGE IN SKIDDING RESISTANCE WITH INCREASE IN SPEED. RECOMMENDATIONS ARE MADE FOR FUTURE WORK TO CONTINUE THE DEVELOPMENT OF VARIOUS METHODS OF TEXTURING. /RRL/A/]]></description>
      <pubDate>Mon, 10 May 1971 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/100866</guid>
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      <title>ROAD SURFACE TEXTURE AND THE CHANGE IN SKIDDING RESISTANCE WITH SPEED</title>
      <link>https://trid.trb.org/View/98765</link>
      <description><![CDATA[PAST WORK HAS INDICATED THAT ON WET ROADS THE RATE OF DECREASE OF SKIDDING RESISTANCE WITH SPEED IS LARGELY DEPENDENT ON THE COARSENESS OF THE ROAD SURFACE TEXTURE. ON SMOOTH, FINE-GRAINED SURFACES THE COEFFICIENT DECREASES RAPIDLY WITH SPEED, BUT ON COARSE-TEXTURED SURFACES THE DECREASE IS MUCH LESS RAPID. TESTS HAVE NOW BEEN CARRIED OUT TO EXAMINE MORE CLOSELY THE WAY IN WHICH COEFFICIENTS DECREASE WITH SPEED UP TO 80 MILE/H AND TO ATTEMPT TO FIND A QUANTITATIVE MEASURE OF SURFACE TEXTURE WHICH WILL INDICATE THE RATE OF FALL IN COEFFICIENT WITH SPEED. TWO TECHNIQUES OF MEASURING TEXTURE HAVE BEEN EXAMINED: THE 'SAND-PATCH' METHOD FROM WHICH A MEASURE OF 'TEXTURE DEPTH' CAN BE OBTAINED, AND A NEW STEREOPHOTOGRAMMETRIC TECHNIQUE WHICH RECORDS THE SURFACE PROFILE. A STATISTICAL CORRELATION HAS BEEN OBTAINED BETWEEN THE PERCENTAGE DECREASE IN COEFFICIENT BETWEEN 30 AND 80 MILE/H AND THE TEXTURE DEPTH, WHICH MEASURES THE COARSENESS OF TEXTURE. RECOMMENDATIONS FOR TEXTURE-DEPTH REQUIREMENTS FOR FAST ROADS ARE GIVEN: TO RESTRICT THE DECREASE TO LESS THAN ABOUT 25 PER CENT, A TEXTURE DEPTH OF MORE THAN 0.025 IN APPEARS NECESSARY. A BETTER CORRELATION WITH PERCENTAGE DECREASE IN COEFFICIENT IS OBTAINED BY A MEASURE OF THE SURFACE PROFILE (THE 'PROFILE RATIO') WHICH TAKES INTO ACCOUNT THE SHAPE OF PROJECTIONS IN THE SURFACE. /AUTHOR/]]></description>
      <pubDate>Mon, 22 Jun 1970 00:00:00 GMT</pubDate>
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