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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>
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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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    <item>
      <title>Performance Comparison of Abutment and Retaining Wall Drainage Systems</title>
      <link>https://trid.trb.org/View/1507624</link>
      <description><![CDATA[Control of water infiltration and providing adequate drainage are critical to the performance of retaining walls and abutment walls. Current Ohio Department of Transportation (ODOT) practice for drainage of structures specifies the use of a two-foot porous backfill with filter fabric, which has a long performance history. ODOT is seeking alternative drainage systems that are more cost- and time-effective, durable, and at the same time, have comparable or superior drainage capability compared to current practice. A prefabricated composite drainage system (PCDS) is proposed in this research as an alternative structure drainage system. The current state of practice of drainage systems for retaining wall and bridge abutment structures is evaluated through a survey of county agencies in Ohio. Commercially available PCDS products as well as specifications for PCDS used by other state DOTs are also reviewed and synthesized. Laboratory testing and evaluation of select PCDS products are conducted to improve the understanding of their properties. It is found that tested values for some properties of some products do not match those listed by the manufacturers. Recommendations on the selection of proper standard testing methods and suggestions on the selection of factory of safety in design are discussed. Field performance of the PCDS system and the traditional drainage system are evaluated with in situ instruments including piezometers, tiltmeters and flumes. The data analysis suggests that the PCDS has comparable drainage capability to the traditional system. Field observation and feedback from the contractor reveal that installation of PCDS systems are less labor-intensive and more time-effective. Cost analysis from ODOT historical bidding data and the actual cost at the tested sites demonstrates that a PCDS system costs 40% less than the traditional process. Based on the findings, draft specifications were developed to specify the material and construction requirements for a PCDS system.]]></description>
      <pubDate>Mon, 30 Apr 2018 19:22:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/1507624</guid>
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    <item>
      <title>CLOSURE ON BEHAVIOR OF A COLLUVIAL SLOPE</title>
      <link>https://trid.trb.org/View/122578</link>
      <description><![CDATA[SOME INTERESTING POINTS CONCERNING THE DRAINAGE FACILITIES AND MOVEMENT OF GROUNDWATER IN THE SLOPE WERE RAISED BY BANERJEE.  THE STABILIZATION SCHEME WAS DESIGNED ON THE BASIS OF A PRELIMINARY SUBSURFACE INVESTIGATION WHEN IT WAS PLANNED TO CONSTRUCT THE LOWER GALLERY NEAR THE COLLUVIUM-ROCK INTERFACE ABOVE THE SHALE AT ELEVATION 760. HOWEVER, DUE TO PROPERTY RESTRICTIONS, THE LOWER GALLERY IS PARTLY IN SOIL AND PARTLY IN ROCK.  AS MORE DETAILED INFORMATION BECAME AVAILABLE DURING CONSTRUCTION AND INSTALLATION OF FIELD MEASUREMENT DEVICES, IT BECAME CLEAR THAT THE LOWER GALLERY WOULD NOT BE AS USEFUL AS ORIGINALLY ANTICIPATED.  THE RATE OF PORE PRESSURE DISSIPATION DUE TO THE INSTALLATION OF DRAINAGE FACILITIES IN RELATION TO THE RATE OF PROGRESSIVE FAILURE IS THE KEY FACTOR IN PRESERVING THE LONG-TERM STABILITY OF THE SLOPE.  HOWEVER, A SYSTEMATIC ANALYSIS OF THE RATE OF DRAWDOWN WAS NOT POSSIBLE DUE TO THE EXTREMELY HETEROGENEOUS NATURE OF THE COLLUVIUM AND THE RESULTING DIFFICULTY IN ASSESSING SOIL PERMEABILITY. NUMEROUS PIEZOMETER SENSITIVITY TESTS WERE CONDUCTED AND THERE WAS NO REASONABLE CORRELATION BETWEEN ONE PIEZOMETER AND THE NEXT.  BANERJEE IS CORRECT THAT IF THE PIEZOMETER HEAD DROP IS SLOWER THAN THE PROGRESSIVE STRENGTH LOSS, INSTABILITY IS POSSIBLE.  FOR THIS REASON, SLOPE INDICATORS WERE INSTALLED TO FOREWARN OF RESULTING MOVEMENT SO THAT REMEDIAL MEASURES COULD BE TAKEN QUICKLY.  NO ESTIMATES WERE MADE REGARDING THE DRAWDOWN AT THE TOE RESULTING FROM THE SAND DRAINS.  A RUNOFF ANALYSIS WAS CONDUCTED TO EVALUATE THE EFFECTS OF PRECIPITATION ON THE STABILITY. REFERENCES: BEHAVIOUR OF A COLLUVIAL SLOPE, E. D'APPOLONIA, R. APLERSTEIN, D. J. D'APPOLONIA, JOURNAL OF SOIL MECHANICS AND FOUNDATIONS DIVISION, PROCEEDINGS OF THE AMERICAN SOCIETY OF CIVIL ENGINEERS, PROCEEDINGS PAPER 5326, JULY 1967.]]></description>
      <pubDate>Sun, 15 Aug 2004 02:44:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/122578</guid>
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    <item>
      <title>MAINE INTERSTATE PROJECT TESTS VERTICAL SAND DRAINS</title>
      <link>https://trid.trb.org/View/122471</link>
      <description><![CDATA[SOILS UNDERLYING THE TIDAL FLATS AND SURROUNDING LAND AREAS OF PORTLAND, MAINE, ARE DEEP, WEAK, COMPRESSIBLE DEPOSITS OF SILT-CLAYS, SOME OF WHICH LOSE STRENGTH SHARPLY WHEN THEY ARE REMOLDED. INTERSTATE 295 HAD TO BE DESIGNED OVER THIS TYPES OF SENSITIVE CLAY. A PLAN WAS DEVELOPED FOR ELABORATE EXPERIMENTAL VERTICAL SAND DRAIN INSTALLATIONS IN THE CRITICAL AREAS. HUNDREDS OF SAND DRAINS WERE INSTALLED AT THE TEST SITES, USING THREE DIFFERENT METHODS: (1) DRIVING WITH A CLOSED-END MANDREL, (2) JETTING AN OPEN-END MANDREL, AND (3) AUGERING. VARIOUS TEST DEVICES WERE INSTALLED IN THE SAND DRAIN AREAS TO PROVIDE INFORMATION THAT WAS NEEDED TO CONTROL FILL PLACEMENT AND EVALUATE DRAIN PERFORMANCE. THE DEVICES INCLUDE SETTLEMENT PLATFORMS, CONVENTIONAL AND VIBRATING-WIRE PIEZOMETERS, SLOPE INDICATORS AND ALIGNMENT STAKES. A HIGH-PRESSURE OIL PIPELINE MUST BE RELOCATED REQUIRING A HIGH EMBANKMENT TO STABILIZE THE FOUNDATION FOR THE PLANNED PIPELINE CROSSING. THE STABILIZATION FILL FOR THE PIPELINE CROSSING IS ABOUT 450 FT LONG, 250 FT WIDE. ONE SECTION OF IT RISES TO ELEVATION PLUS 40. ALL THE SAND DRAINS UNDER THIS FILL WERE FORMED WITH A DRIVEN, CLOSED-END MANDREL. DATA FROM THESE VERTICAL SAND DRAIN TESTS ARE NOW BEING ANALYZED.]]></description>
      <pubDate>Sun, 15 Aug 2004 02:43:35 GMT</pubDate>
      <guid>https://trid.trb.org/View/122471</guid>
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    <item>
      <title>APPLICATION OF AIRPHOTO INTERPRETATION TECHNIQUES</title>
      <link>https://trid.trb.org/View/121292</link>
      <description><![CDATA[A SOIL CLASSIFICATION SYSTEM COMPRISING SEVEN UNITS IS DESCRIBED WITH RESPECT TO: PHYSICAL CHARACTERISTICS OF THE SOIL, SUBSURFACE DRAINAGE CONDITIONS, FROST SUSCEPTIBILITY, SETTLEMENT CHARACTERISTICS, RELIEF, EASE OF EXCAVATION, AND OTHER SIGNIFICANT CHARACTERISTICS. RECONNAISSANCE ENGINEERING SOIL MAPS FOR AN AREA OF ABOUT 4,000 SQ MI, AND HUNDREDS OF MILES OF SOIL STRIP MAPS, HAVE BEEN PREPARED. APPLICATION OF THE PROCEDURE IN SOIL AND MATERIALS STUDIES FOR A SPECIFIC ROUTE STUDY, AND ACCURACY OF THE SOIL MAPPING ARE DESCRIBED. /AUTHOR/]]></description>
      <pubDate>Sun, 15 Aug 2004 02:38:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/121292</guid>
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    <item>
      <title>CONSTRUCTION PORE PRESSURES IN THREE EARTH DAMS</title>
      <link>https://trid.trb.org/View/120418</link>
      <description><![CDATA[HIGH CONSTRUCTION PORE PRESSURES DEVELOPED IN TWO OF THE THREE DAMS BUILT WITH THE SAME TYPE OF RESIDUAL SOIL UNDER SIMILAR CONDITIONS. THE DEVELOPMENT OF PORE PRESSURE IS DUE TO THE COMBINED EFFECT OF MANY FACTORS-MOISTURE CONTENT, SOIL GRADATION, DEGREE OF COMPACTION, RATE OF CONSTRUCTION, AND DRAINAGE FEATURES IN A DAM. IN A FILL OF THE RESIDUAL SOIL STUDIED WHICH HAS HIGH NATURAL MOISTURE CONTENT, OVER- COMPACTION MAY INDUCE HIGH PORE PRESSURE, IF THE SOIL CONTAINS LESS THAN 30 PER CENT MINUS 200-SIEVE SIZES, ITS FILL IS NOT LIKELY TO DEVELOP HIGH PORE PRESSURE, THE DRAINAGE SYSTEM IN THE FILL WOULD NOT BE EFFECTIVE IN REDUCING PORE PRESSURE IF THE RATE OF CONSTRUCTION IS HIGH. THE DEVELOPMENT OF TEMPORARILY HIGH CONSTRUCTION PORE PRESSURE IN AN EARTH DAM PRESENTS A MAJOR PROBLEM IN DESIGN FROM THE VIEW POINTS OF SAFETY AND ECONOMY WHICH MAY OFTEN REQUIRE AN UNCONVENTIONAL METHOD OF SOLUTION. /AUTHOR/]]></description>
      <pubDate>Sun, 15 Aug 2004 02:35:21 GMT</pubDate>
      <guid>https://trid.trb.org/View/120418</guid>
    </item>
    <item>
      <title>HYDRAULIC BEHAVIOR OF GEOTEXTILE FILTERS IN THE FIELD</title>
      <link>https://trid.trb.org/View/541277</link>
      <description><![CDATA[Filters are often used to prevent particles from migrating into a drainage system, while simultaneously evacuating excess water from soils.  The water must percolate through the soil and then the filter before entering the system.  Therefore, a filter must be selected that will restrain the piping of migrating particles while simultaneously permitting water discharge.  The advantages of using geotextile filters in drainage are the following: geotextiles act as a filter to allow water entry but prevent migration of fine soil particles into drainage, geotextiles effectively increase the inlet of the drainage system, and geotextiles reduce hydraulic gradients near drain tubes. Geotextile filters also have important advantages over mineral filters:  they are easier and less costly to install, and they allow easier quality control.  This article, which is the eighth installment of this journal's filtration series, applies the hydraulic principals discussed in previous series articles to three varied case histories involving geotextile filters: subsurface agricultural drainage systems in Ormstown, Canada; municipal roadway drainage in LaSalle, Montreal, Canada; and coastal erosion protection in Miami Beach, Florida.  After 3-30 years of service, geotextile filters were found to be efficient in retaining soil particles without restricting water flow.]]></description>
      <pubDate>Mon, 30 Nov 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/541277</guid>
    </item>
    <item>
      <title>HOUSTON ROLLS OUT STREET WORK</title>
      <link>https://trid.trb.org/View/635737</link>
      <description><![CDATA[After nearly 20 years of debate and an affirmative action lawsuit, the Houston Metropolitan Transit Authority has begun a $215-million city street reconstruction.  Contractors will replace asphalt with concrete on 34 mi (55 km) of downtown and midtown streets.  The project will provide narrower streets, wider sidewalks, and new bus stop shelters and information kiosks.  The work, which began June 17, 1998, will be awarded in 57 contracts, providing more opportunities to smaller contractors, and will take 5 years to complete.  The project includes some unusual features such as streets that drain away from the curbs.  The outer lanes of downtown streets will feature an inverted crown to divert stormwater into two 64-ft-long (19.8-m) concrete trench drains covered with 9-in (23-cm) grates in the middle of the lane.]]></description>
      <pubDate>Thu, 03 Sep 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/635737</guid>
    </item>
    <item>
      <title>A GEOCOMPOSITE CHANNELS EL NINO'S FURY</title>
      <link>https://trid.trb.org/View/487601</link>
      <description><![CDATA[The excessive rain of El Nino served as a "trial by water" for a recently completed drainage system in Orange County, California's Eastern Transportation Corridor, a new toll road project.  The challenge was magnified by southern California's unique hydrology, in which half of the region's annual precipitation can fall during a single severe winter storm.  Because the nearby mountains have little absorption capacity, low-lying areas are at risk of flash flooding.  The final drainage plan called for 2 mi (3 km) of new flood-control channels, designed to handle 100-year flow rates of up to 16,371 cu ft/sec (464 cu m/sec). With an October 1997 deadline and the beginning of the rainy season looming, construction of the channels began in June 1997. The need for speed was the main reason that the contractor chose a geocomposite instead of a traditional crushed-gravel backdrain. The geocomposite was also a good solution for relieving hydrostatic pressure along the steep channel walls where gravel could not be used.  After excavation, crews laid the drainage membrane on the exposed soil of both the inclines and the base. They installed rebar on top of it, then poured concrete to a depth of 12-14 in (305-356 mm).  Despite some of the fiercest storms and heaviest precipitation in this century, the new flood-control channels appear sufficient for their load.]]></description>
      <pubDate>Tue, 28 Jul 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/487601</guid>
    </item>
    <item>
      <title>DAMAGES TO WASTEWATER SYSTEMS (1995 HYOGOKEN NANBU EARTHQUAKE)</title>
      <link>https://trid.trb.org/View/477840</link>
      <description><![CDATA[A total of 102 sewage treatment plants were in operation when sewerage systems in Hyogo, Kyoto and Osaka Prefectures received the devastating impacts of the 1995 Hyogoken Nanbu Earthquake. Of the total, 43 plants were damaged by the earthquake.  In particular, 8 plants in Hyogo Prefecture were heavily damaged and were forced to suspend, wholly or partially, their operation.  As for pumping stations, 56 facilities were damaged. Sewer systems were damaged at about 1,600 locations according to visual inspection on roads or through manholes.  Detailed study revealed that the total length of damage was approximately 162 km.  Compared to known earthquake damage, the displacement of joints, cracks and similar damage were observed more frequently, while the relief or subsidence of sewers due to soil liquefaction was less extensive.  In addition, significant damage was observed in branch sewers, laterals and drainage facilities.]]></description>
      <pubDate>Fri, 24 Apr 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/477840</guid>
    </item>
    <item>
      <title>CITY CALLS MOTHER NATURE'S BLUFF WITH LANDSLIDE PROJECT</title>
      <link>https://trid.trb.org/View/469145</link>
      <description><![CDATA[When a landslide destroyed five San Clemente homes and sent them tumbling onto a highway and railroad track in Dana Point, California, the tiny seaside community lead a 2-year effort to rebuild and strengthen the collapsed bluff and to reopen the road.  This article reports that the erosion control effort was a combination of projects that included:  rebuilding the collapsed bluff and strengthening it with large tie-back anchors; applying a shotcrete surface to further strengthen the bluff; installing a drainage system in the bluff face; utilizing a latex mold of rock, sculpted concrete surfaces, stain and landscaped groundcover to hide the construction and replicate the bluff's natural face; working with local, state, and federal agencies and a private group to permit and finance the project; and keeping residents informed of details and progress of restoration through open houses and newletters.  The $3.5 million bluff restoration was funded via state, federal, and private dollars.]]></description>
      <pubDate>Tue, 23 Dec 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/469145</guid>
    </item>
    <item>
      <title>SUBSURFACE DRAINAGE SYSTEMS IN ROADWAY CONSTRUCTION</title>
      <link>https://trid.trb.org/View/474468</link>
      <description><![CDATA[The installation of subsurface drainage systems has been a common practice in roadway construction for many years.  Until recently, however, the ability to inspect and report on the condition of these systems once they are in place has been limited.  The use of a high-tech, closed-circuit video monitoring system for the inspection of subsurface drainage systems has been developed and utilized with a high degree of success.  The use of this system is beneficial for maintenance and rehabilitation of existing systems and as a quality control measure for new highway systems.  In an ongoing project for FHWA, video monitoring has identified crushed mainline drainage pipes in new systems that have yet to be open to traffic.  All of the components of this monitoring system can be easily operated by one person in the field.  Substantial cost savings can be realized by accurately identifying the specific areas that need repair rather than assuming that an entire system needs to be replaced in highway rehabilitation projects. Results from use of this new technology to date are presented here.]]></description>
      <pubDate>Mon, 08 Dec 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/474468</guid>
    </item>
    <item>
      <title>STABILIZATION OF EXISTING SUBGRADES TO IMPROVE CONSTRUCTIBILITY DURING INTERSTATE PAVEMENT RECONSTRUCTION</title>
      <link>https://trid.trb.org/View/474206</link>
      <description><![CDATA[This synthesis will be of interest to state department of transportation (DOT) construction, geotechnical, materials, and pavement system design engineers, engineering geologists, and research engineers, and others concerned with the constructibility of new pavements over existing subgrades.  The synthesis describes current practice for the stabilization of existing subgrades to improve constructibility during interstate pavement reconstruction.  It presents information regarding the methods available to evaluate and improve subgrade conditions for the purpose of meeting the constructibility requirements of a reconstruction project.  This report of the Transportation Research Board presents data obtained from a review of the literature and a survey of the state DOTs.  The synthesis reports on:  subgrade evaluation methods including sampling, laboratory, and in-situ test methods, as well as assessment of existing drainage systems; constructibility factors such as existing and proposed pavement types, available equipment, and cost effectiveness of various subgrade stabilization techniques; methods of subgrade improvement including mechanical and chemical stabilization, use of recycled and waste materials, the use of geosynthetics in reinforcement and drainage applications; and construction methods with an emphasis on innovative approaches such as novel sequencing of construction traffic, use of lightweight equipment, and robotics.  In addition, several case histories describing applicable pavement reconstruction projects are presented.  Finally, suggestions to possibly improve the practice and the identification of research needs are also presented.]]></description>
      <pubDate>Tue, 02 Dec 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/474206</guid>
    </item>
    <item>
      <title>EFFECTIVENESS OF HIGHWAY-DRAINAGE SYSTEMS IN PREVENTING CONTAMINATION OF GROUND WATER BY ROAD SALT, ROUTE 25, SOUTHEASTERN MASSACHUSETTS--DESCRIPTION OF STUDY AREA, DATA COLLECTION PROGRAMS, AND METHODOLOGY</title>
      <link>https://trid.trb.org/View/471464</link>
      <description><![CDATA[Four test sites along a 7-mile (11-kilometer) section of Route 25 in southeastern Massachusetts, each representing a specific highway-drainage system, were instrumented to determine the effectiveness of the drainage systems in preventing contamination of ground water by road salt.  One of the systems discharges highway runoff onsite through local drainpipes.  The other systems use trunkline drainpipes through which runoff from highway surfaces, shoulders, and median strips is diverted and discharged into either a local stream or a coastal waterway. Route 25 was completed and opened to traffic in the summer of 1987.  Road salt was first applied to the highway in the winter of 1987-88.  The study area is on a thick outwash plain composed primarily of sand and gravel.  Watertable depths range from 15 to 60 ft (4.6 to 18.3 m) below land surface at the four test sites.  Ground-water flow is in a general southerly direction, approximately perpendicular to the highway.  Streamflow in the study area is controlled primarily by ground-water discharge. Background concentrations of dissolved chloride, sodium, and calcium--the primary constituents of road salt--are similar in ground water and surface water and range from 5 to 20, 5 to 10, and 1 to 5 milligrams per liter, respectively.  Data-collection programs were developed for monitoring the application of road salt to the highway, the quantity of road-salt water entering the ground water, diverted through the highway-drainage systems, and entering a local stream.  The Massachusetts Highway Department monitored road salt applied to the highway and reported these data to the U.S. Geological Survey.  The U.S. Geological Survey designed and operated the ground-water, highway-drainage, and surface-water data-collection programs.  A road-salt budget will be calculated for each test site so that the effectiveness of the different highway-drainage systems in preventing contamination of ground water by road salt can be determined.]]></description>
      <pubDate>Wed, 26 Nov 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/471464</guid>
    </item>
    <item>
      <title>URBAN DRAINAGE DESIGN MANUAL: HYDRAULIC ENGINEERING CIRCULAR NO. 22</title>
      <link>https://trid.trb.org/View/573519</link>
      <description><![CDATA[This circular provides a comprehensive and practical guide for the design of storm drainage systems associated with transportation facilities.  Design guidance is provided for the design of storm drainage systems which collect, convey, and discharge stormwater flowing within and along the highway right-of-way.  Methods and procedures are given for the hydraulic design of storm drainage systems.  Design methods are presented for evaluating rainfall and runoff magnitude, pavement drainage, gutter flow, inlet design, median and roadside ditch flow, structure design, and storm drain piping.  Procedures for the design of retention facilities and stormwater pump stations are also presented, along with a review of urban water quality practices.  A summary of related public domain computer programs is also provided.]]></description>
      <pubDate>Tue, 16 Sep 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/573519</guid>
    </item>
    <item>
      <title>BOTTOM OUTLET FOR SEWERS</title>
      <link>https://trid.trb.org/View/576384</link>
      <description><![CDATA[The bottom opening is a standard structure in storm sewers, provided the approach flow is supercritical.  Based on extended experimentation and by using the governing flow equations, the hydraulic characteristics of bottom openings were derived. These include the approach reach, the end depth ratio, the average discharge coefficient, the tailwater depth, and the hydraulic loss across the outlet.  Further, velocity distributions in the outlet zone are discussed.  The results of this study reveal that the approach Froude number has a significant effect on the flow mechanism.  General expressions are derived for the lower and upper nappes of the flow across the bottom opening, and a hydraulic design procedure is described.  A generalized streamwise coordinate is also introduced that allows description of supercritical sewer flow. It is demonstrated that the excess discharge to the treatment station under design discharge is within the requirements of European standards.]]></description>
      <pubDate>Wed, 20 Aug 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/576384</guid>
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