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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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      <title>Acoustic Approach to Determining Seabed Substrates Distribution at Mandi Darah Island, Sabah</title>
      <link>https://trid.trb.org/View/1901981</link>
      <description><![CDATA[Marine ecosystems and natural habitat play the important role of the Earth’s life support system. They significantly contribute to economies and food safety and help preserve ecological processes. However, the devastation of the marine ecosystem in Malaysia due to the human factor and climate change is quite alarming. Therefore, spatial marine information, especially on the distribution of seabed substrates and habitat mapping, are of utmost importance for marine ecosystem management and conservation. Traditionally, seabed substrate and habitat mapping were classified based on direct observation techniques such as photography, video, sampling, coring and scuba diving. These techniques are often limited due to water clarity and weather conditions and only suitable for smaller scale surveys. In this study, the authors employed an acoustic approach using the RoxAnn Acoustic Ground Discrimination System (AGDS) with a high-frequency single-beam echo sounder to examine the distribution of seabed substrate at the Mandi Darah Island, Sabah. The acoustic signals recorded by AGDS are translated into hardness and roughness indices which are then used to identify the unique characteristics of the recorded seabed types. The analysis has shown that fifteen types of substrates, ranging from silt to rough/some seagrass, have been identified and classified. The findings demonstrated that the acoustic method was a better alternative for seabed substrate determination than the conventional direct observation techniques in terms of cost and time spent, especially in large scale surveys. The seabed substrate dataset from this study could be used as baseline information for the better management and conservation of the marine ecosystem.]]></description>
      <pubDate>Tue, 25 Jan 2022 09:50:49 GMT</pubDate>
      <guid>https://trid.trb.org/View/1901981</guid>
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    <item>
      <title>Impacts of Channel Reconstruction in the Pilchuck River</title>
      <link>https://trid.trb.org/View/1374107</link>
      <description><![CDATA[A five-year study was performed to compare conditions in the Pilchuck River before and after channel reconstruction associated with rerouting highway SR-2. The study focused on sediment particle-size analyses, benthic macroinvertebrates and fish. Substrates comparable to control areas developed in all portions of the new channel within one year after construction. The available data on invertebrates and fish gave no indication of deterioration in diversity, quantity or size in the reconstructed channel. The report provides recommendations for further improvements in the design of stream channel changes should there be no alternative to their construction.]]></description>
      <pubDate>Sat, 21 Nov 2015 17:31:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/1374107</guid>
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    <item>
      <title>Evaluation Of Waste Concrete Road Materials For Use In Oyster Aquaculture – Field Test</title>
      <link>https://trid.trb.org/View/1360045</link>
      <description><![CDATA[The overall objective of this study was to determine the suitability of recycled concrete aggregate (RCA) from road projects as bottom conditioning material for on-bottom oyster aquaculture in the Chesapeake Bay. During this Phase of the study, the research team placed RCA on test plots in the Chesapeake Bay to evaluate the impact on the benthic community. Miniature oyster reefs were also built to determine potential impacts or disruptions of RCA on the use of traditional harvesting gear. The results of this project showed that 1.) There was no significant difference between substrate type (RCA, oyster shell) on benthic community structure, oyster recruitment, and the abundance and size distribution of key faunal species, demonstrating that RCA, as an alternative material, was generally similar to natural oyster shell with regard to ecosystem services provided, and 2.) RCA makes a suitable substrate for supporting oysters for aquaculture operations but would require a veneer of old shell to be placed on top so as not to introduce additional weight to the catch when using shaft tongs.]]></description>
      <pubDate>Tue, 21 Jul 2015 09:37:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/1360045</guid>
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    <item>
      <title>A Review of the Influences of Road Crossings on Warmwater Fishes in Ouachita Mountain Streams, Ouachita National Forest</title>
      <link>https://trid.trb.org/View/1349035</link>
      <description><![CDATA[Several studies have measured the influence of road crossings on fish movement and on fish communities within the Ouachita National Forest. In an initial study, passage of more than a hundred darters through a baffled pipe and over a grouted rip-rap ramp was documented over nine weeks. A broader study of fish movements associated with nine crossings ranging from natural-bottomed fords to piped crossings showed that natural ford and box culverts allowed unrestricted fish passage, but other designs were associated with reduced passage or none at all. Six piped crossings were examined in more detail including three that were modified in an attempt to improve fish passage. Fish were less likely to move across reaches with these low-water bridges compared to nearby natural reaches without low-water bridges. Average species richness was higher for fish communities downstream of the crossings compared to upstream (12.5 versus 6.3). Two rip-rapped low-water crossings were the only ones where upstream fish passage was detected. In a study of leopard darters, only one individual was detected moving downstream through a low-water crossing and none were found moving upstream. In an extensive study of twenty-one randomly selected low-water crossings, species richness was greater downstream versus upstream (9.4 versus 7.1, respectively). Total abundance (total number of all individuals of all species) was also significantly lower in the combined upstream reaches versus the combined downstream reaches. New box culvert installations indicated limited success in upstream passage, though detection of marked fish was quite low. Watershed-scale road and crossing densities were not significantly related to diversity and abundance of warmwater fishes or smallmouth bass density and biomass. Another study looking strictly at the effects of low-water crossings on stream geomorphology found stream widening upstream, stream incision downstream and changes in substrates when compared to a representative reach without a crossing. Work continues in designing, constructing and monitoring crossings that will pass fish]]></description>
      <pubDate>Tue, 28 Apr 2015 15:09:35 GMT</pubDate>
      <guid>https://trid.trb.org/View/1349035</guid>
    </item>
    <item>
      <title>Managing Invasive Species Risks for Bridge Pontoons Stored in Estuaries</title>
      <link>https://trid.trb.org/View/1347674</link>
      <description><![CDATA[WSDOT (Washington State Department of Transportation) has developed and maintains several floating bridges. These floating bridges resemble vessels and require long lead times and specialized construction techniques for pontoon construction. In 2007, WSDOT identified the need to develop pontoons in preparation for potential catastrophic failure of the SR 520 Bridge that spans Lake Washington between Seattle and its eastern suburbs. This planning and construction effort will result in the development of 33 pontoons, enough to replace nearly 1.5 miles of 4-lane bridge supported by pontoons. While concurrent planning efforts are preparing to replace the bridge, there is projected to be a potential gap between the date when pontoons are built and when they are needed to support construction of the new bridge. This temporal gap may necessitate inwater storage of pontoons. The pontoons are being built in a casting basin approximately 250 nautical miles from their ultimate destination, and storage is planned to occur in the Grays Harbor estuary near the fabrication site. Before pontoons can be deployed in the freshwater Lake Washington, it is assumed they will be outfitted with bridge superstructure at a marine pier in Puget Sound. Hull fouling is expected to occur during moorage in Grays Harbor. Several species of non-indigenous species are known or suspected to occur in Grays Harbor that have not yet been detected in Puget Sound, creating a risk that nonindigenous species could be transported to Puget Sound as a component of the hull fouling community that develops on pontoons. Species of concern include colonial tunicates and European green crab. Pontoons for the Hood Canal floating bridge were stored in Port Gamble Bay for approximately twenty years before they were outfitted with bridge superstructure and incorporated into partial replacement of that bridge. Scuba investigations of those pontoons in 2009 suggested that substantial and diverse hull fouling communities can develop on pontoons that are not substantially diminished by pontoon transport. To address concerns about hull fouling communities and the potential risk of transporting non-indigenous species between Grays Harbor estuary and Puget Sound, WSDOT developed a two-pronged strategy for managing invasive species risk. WSDOT would either limit moorage to brief durations so hull fouling communities are limited and represent a low risk for harboring non-indigenous species, or pontoons that developed hull fouling communities would be cleaned using underwater equipment to scrape the hull. To help inform these strategies WSDOT deployed a field investigation to assess the rate of development of hull fouling communities on pontoons. Four concrete plates were deployed in Grays Harbor in the vicinity of the future pontoon moorage site in October 2010. These plates were deployed at two depths representing the near waterline and near bottom depths of the pontoons during moorage. Concrete plates are retrieved and inspected every 3 months to assess the settlement and establishment of organisms on the substrate. Results of this field assessment are then used to identify moorage durations that may require hull cleaning prior to transport to Puget Sound to limit the risk of transporting non-indigenous species.]]></description>
      <pubDate>Tue, 31 Mar 2015 08:53:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/1347674</guid>
    </item>
    <item>
      <title>Evaluation Of Waste Concrete Road Materials For Use In Oyster Aquaculture – Field Test</title>
      <link>https://trid.trb.org/View/1345499</link>
      <description><![CDATA[The overall objective of this study was to determine the suitability of recycled concrete aggregate (RCA) from road projects as bottom conditioning material for on-bottom oyster aquaculture in the Chesapeake Bay. During this Phase of the study, the research team placed RCA on test plots in the Chesapeake Bay to evaluate the impact on the benthic community. Miniature oyster reefs were also built to determine potential impacts or disruptions of RCA on the use of traditional harvesting gear. The results of this project showed that (1) There was no significant difference between substrate type (RCA, oyster shell) on benthic community structure, oyster recruitment, and the abundance and size distribution of key faunal species, demonstrating that RCA, as an alternative material, was generally similar to natural oyster shell with regard to ecosystem services provided, and (2) RCA makes a suitable substrate for supporting oysters for aquaculture operations but would require a veneer of old shell to be placed on top so as not to introduce additional weight to the catch when using shaft tongs.]]></description>
      <pubDate>Thu, 12 Mar 2015 07:53:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/1345499</guid>
    </item>
    <item>
      <title>Evaluation of Repair Techniques When Bonding Repair Materials to Forty-Year Old Concrete Substrate</title>
      <link>https://trid.trb.org/View/1243819</link>
      <description><![CDATA[Three types of surface preparation methods were tested with two different repair materials on forty-year old concrete taken from a deteriorated bridge bent. In addition, bonding agents were applied to determine if they would increase bonding strength. Mechanical hammering was used on all surfaces prior to specific surface conditioning methods combined with bonding agents so that the method could be evaluated on how well micro-cracking was removed. Failure within the substrate was categorized as the most important determination of satisfactory performance. Bond strengths, surface roughness and modulus of elasticity were also measured and used as ways to evaluate surface conditioning methods, bonding agent usefulness and repair material performance. The results of this research show that mechanical hammering without further surface conditioning results in lower bond strengths and higher percentages of failures at the repair/substrate interface. No conclusion could be made as to what surface conditioning method is ideal; high-pressure water-jetting however performed consistently. Surfaces with a scrubbed grout coating of the same material properties as the repair mix experienced the highest percentage of failures within the substrate material.]]></description>
      <pubDate>Tue, 19 Feb 2013 15:03:29 GMT</pubDate>
      <guid>https://trid.trb.org/View/1243819</guid>
    </item>
    <item>
      <title>Culvert Roughness Elements for Native Utah Fish Passage: Phase II</title>
      <link>https://trid.trb.org/View/1147974</link>
      <description><![CDATA[Native fishes have become an increasingly important concern when designing fish passable culverts. Many operational culverts constrict waterways which increase velocities and prevent upstream passage of small fish species. The current method to ensure fish passage is to match the average cross sectional velocity to the sustained swim speed of the fish. This study investigates the passage rates of leatherside chub (Lepidomeda aliciae) and speckled dace (Rhinichthys osculus) at three sites (an arch culvert with substrate bottom, box culvert with bare bottom, and a stream section with no culvert) located on Salina Creek near Salina, UT. It was found that fish were able to pass through all of the sites. However, fish were able to take advantage of the habitat within the culvert that had a substrate bottom more effectively than within the culvert that had no substrate within the barrel. This was reflected in population density estimates at each of the three test sites for each species. It was also found that the substrate at the arch culvert and stream sites scaled with the fish measured in this study. The D50 and D84 were 44 and 205 mm at the arch culvert site and 26 and 126 mm at the stream site. The average fish length was 76 mm for the chub and 64 mm for the dace. It is believed that placing substrate that scales with fish length within the culvert will provide enough velocity heterogeneity to allow the fish to successfully pass.]]></description>
      <pubDate>Wed, 22 Aug 2012 15:37:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/1147974</guid>
    </item>
    <item>
      <title>Culvert Roughness Elements for Native Utah Fish Passage: Phase I</title>
      <link>https://trid.trb.org/View/1105037</link>
      <description><![CDATA[Laboratory flume testing of native Utah non-salmonid fish was performed to observe how they use altered flow around obstacles to swim upstream. Three experimental setups included a bare Plexiglas flume, vertical cylinders, and natural substrate placed in the flume. It was found that substrate provides the most refuge for upstream swimming fish. Field tested results of these experimental findings in Phase II will allow engineers to take advantage of reduced velocity zones in retrofitted culvert design.]]></description>
      <pubDate>Tue, 28 Jun 2011 16:22:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/1105037</guid>
    </item>
    <item>
      <title>Effect of Filtering on Texture Assessment of Concrete Surfaces</title>
      <link>https://trid.trb.org/View/917626</link>
      <description><![CDATA[This article describes how the bond strength of the interface between concrete layers cast at different times is important to ensure the monolithic behavior of reinforced concrete (RC) composite members. The surface roughness of the concrete substrate has a significant influence on the interface strength. The authors developed two methodologies to assess the texture profile of the substrate surface; have proved that numerical parameters can be used to classify its roughness; and showed that some of these correlate well with the interface strength, both in shear and in tension. Because roughness and waviness parameters are obtained from the primary profile using a filter, the selection of the latter has a significant effect on the results. This paper describes a study performed to analyze this effect and to assess if filtering is a necessary step. It was concluded that filtering can be avoided and the surface texture can be characterized only with primary parameters.]]></description>
      <pubDate>Sun, 30 May 2010 07:44:12 GMT</pubDate>
      <guid>https://trid.trb.org/View/917626</guid>
    </item>
    <item>
      <title>Preliminary Study of Scour in Bottomless Culverts</title>
      <link>https://trid.trb.org/View/804158</link>
      <description><![CDATA[Many traditional culvert designs develop into fish barriers due to excessive channel degradation.  Increased concern for and interest in better facilitating fish migration or passage through culverts have fostered alternative culvert designs.  Such culvert designs include "buried-invert" and "bottomless" culverts.  The goal of buried-invert and bottomless culvert designs is to minimize discontinuity between the adjacent natural channel reaches by, in most cases, installing a culvert of sufficient size as to span the entire channel width.  The large culverts minimize the discontinuities in channel width and flow velocities between the culvert and the adjacent channel reaches.  The buried-invert or bottomless culvert geometries also help natural sediment transport processes.  Bottomless culvert research, to date, has primarily focused on fish passage; there is a limited understanding of the hydraulic characteristics of bottomless and buried-invert culverts.]]></description>
      <pubDate>Wed, 21 Mar 2007 15:20:38 GMT</pubDate>
      <guid>https://trid.trb.org/View/804158</guid>
    </item>
    <item>
      <title>Soil Mix and Plant Materials for Washington Bridge</title>
      <link>https://trid.trb.org/View/804155</link>
      <description><![CDATA[Stress resistant plants and lightweight growing substrate mixtures were developed for use on roofs for environmental, economic, and aesthetic benefits as greenroofs.  The goal of this study was to evaluate different greenroof plant and substrate combinations to determine if extensive greenroof technology could be modified for low-cost reduced-maintenance bridge and roadside planters designed for the Rhode Island Department of Transportation (RIDOT). Ten plant taxa: "Allium schoenoprasum" L., "Delosperma aberdeenense" (L.) Bolus., "Drosanthemum hispidum" (L.) Schwant., "Jovibarba hirta" (L.) Opiz. 'Emerald Spring' (Syn. "Sempervivum hirta" L.), "Orostachys iwarenge" Hara. (Syn. "Orostachys boehmeri" Makino; "Sedum boehmeri" L.), "Sedum hispanicum" L. 'Immergraunch', "Sedum japonicum" Sieb., "Sedum spurium" Bieb. 'John Creech', "Sempervivum" L. var. Specialty Blend, and "Talinum calycinum" Engelm., and three growing substrate mixtures suitable for greenroofs: Growing Substrate 1 (GS1; 10% field soil, 10% compost, and 80% Hydrocks™), Growing Substrate 2 (GS2; 20% compost and 80% Norlite), and Growing Substrate 3 (GS3: 40% field soil, 20% compost, and 40% Hydrocks™) were evaluated in mesocosms for use in concrete planters for bridge-top plantings.  Plant area, plant height, growing substrate water content, temperature, nutrition, and weediness were used for comparison.  "A. schoenoprasum D. aberdeenense, D. hispidum, S. hispanicum 'Immergraunch', S. japonicum" were replaced due to winter injury or lodged stems.  These five taxa were replaced with "Allium senescens" (Schrad.) Reg. var. glaucum., "Hylotelephium cyaneum" (Rudolph) H. Ohba. (Syn. "Sedum cyanum" Rudolph) 'Rose Carpet', "Sedum kamtschaticum" Fisch. 'Weihenstephaner Gold', "Sedum lineare' Thumb. 'Golden Teardrop', and "Sedum stenopetalum" Pursh.  Plants growing in GS2 or GS3 had similar area and height increases and water content, while those growing in GS1 yielded the least increases over two growing seasons.  GS2 had less weed growth, greater porosity, and higher nutrient levels than GS3.]]></description>
      <pubDate>Wed, 21 Mar 2007 15:20:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/804155</guid>
    </item>
    <item>
      <title>EVALUATION OF PROTECTIVE COATINGS SYSTEMS FOR BUOYS</title>
      <link>https://trid.trb.org/View/69981</link>
      <description><![CDATA[Thirty-one premium antifouling marine coatings systems have been examined to determine their extended service life potential for steel, aluminum, and plastic buoys. Complete systems of substrate, pretreatments, primers, anticorrosive midcoats, and antifouling topcoats containing various toxicants are included in the program. Eight of the 31 systems are carried over from a previous study (Report No. CG-D-74-75 of March 21, 1975) and have been examined after 77 months of static immersion in seawater near Daytona Beach, Florida. The performance of seven systems is noteworthy, particularly that of the Vinyl-High Rosin Type 121/63 and the elastomeric sheet with organotin toxicant. Performance of the Standard Vinyl Rosin Type 121 in the specification system and over self-cured and post cured zinc silicates with a high build vinyl are slightly poorer but are still rated excellent. The remaining systems are epoxy/epoxy-coal tar and a vinyl rosin containing an organotin fluoride toxicant.]]></description>
      <pubDate>Mon, 19 Aug 2002 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/69981</guid>
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    <item>
      <title>MAPPING OF SUBTIDAL AND INTERTIDAL HABITAT RESOURCES: HOOD CANAL FLOATING BRIDGE, WASHINGTON</title>
      <link>https://trid.trb.org/View/718770</link>
      <description><![CDATA[The Washington State Department of Transportation is planning to repair and replace portions of the Hood Canal Bridge.  To minimize construction impacts, it is important to spatially evaluate the location of biological resources, such as eelgrass (Zostera marina), geoduck clams (Panopea abrupta), and rockfish (Sebastes spp.), near the bridge, particularly at the eastern and western termini, and associated construction sites.  An underwater mapping effort was conducted during January 2001, during a season noted for dieback of eelgrass and senescence, whereas CASI imagery was collected during the summer of 2000 when eelgrass cover was at a maximum.  Although the two methods produced some minor differences in the eelgrass patch margins, the vast majority of the areas overlapped along the eastern terminus where both methods were employed.  Hence, the resulting maps for both the eastern and western termini should be considered accurate delineations of eelgrass (cover type and geopositional accuracy).  At both the eastern and western termini, close to the bridge, a general lack of eelgrass continuity was noted.  However, continuous beds were mapped on both sides at varying distances from the bridge.  The merged intertidal-subtidal eelgrass maps are the result of one of the first integrated mapping efforts of nearshore eelgrass in the Northwest.  The spatially referenced data collected on substrate type, fish, and macroinvertebrates will allow examination of habitat usage in the future near the eastern and western termini of the bridge.]]></description>
      <pubDate>Tue, 16 Jul 2002 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/718770</guid>
    </item>
    <item>
      <title>AN EVALUATION OF SILICON ON SAPPHIRE TECHNOLOGY</title>
      <link>https://trid.trb.org/View/42513</link>
      <description><![CDATA[Silicon on sapphire is a recent microelectronic circuit technology originally devised to eliminate the drawbacks of conventional junction isolation. It has since developed into a high performance MOS-type integrated circuit family. In this report a description of this logic family is given, including such topics as manufacturing processes, device physics, and performance of commercial circuits. The report concludes with an overall evaluation of this technology. (Author)]]></description>
      <pubDate>Sat, 13 Jul 2002 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/42513</guid>
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