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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>Transport Research International Documentation (TRID)</title>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>USE OF BACKWATER IN DESIGNING BRIDGE WATERWAYS</title>
      <link>https://trid.trb.org/View/105466</link>
      <description><![CDATA[HOW IS THE LENGTH OF A BRIDGE OVER A STREAM DETERMINED? THIS QUESTION HAS MANY ANSWERS SINCE BRIDGE ENGINEERS, RESPONSIBLE FOR SUCH DECISIONS, HAVE HAD TO RELY PRINCIPALLY ON PERSONAL OBSERVATION AND EXPERIENCE FOR THE ANSWERS. IN SHORT, NO GENERALLY ACCEPTED METHOD FOR BRIDGE WATERWAY DESIGN HAS EXISTED. A COMPARISON OF THE SMALL NUMBER OF BRIDGE FAILURES TO THE TOTAL NUMBER OF BRIDGES THROUGHOUT THE COUNTRY ATTEST TO THE COMMENDABLE JOB BRIDGE DESIGNERS HAVE PERFORMED WITH THE LIMITED DESIGN TOOLS AVAILABLE. THEIR RECORD IS MOST CERTAINLY IMPRESSIVE. WHAT PROPORTION OF EXISTING BRIDGES ARE UNDER-DESIGNED AND WHAT PROPORTION ARE OVER-DESIGNED FROM THE STANDPOINT OF LENGTH AND CLEARANCE? WITH MANY NEW BRIDGES SCHEDULED TO BE CONSTRUCTED UNDER THE ACCELERATED HIGHWAY PROGRAM, THE ABOVE QUESTION DESERVES SERIOUS THOUGHT FROM THE STANDPOINT OF SAFETY AND ECONOMY. UNDER-DESIGNED BRIDGES USALLY SPEAK FOR THEMSELVES, GIVEN SUFFICIENT TIME. IN THE CASE OF OVER DESIGN, NO RELIABLE STANDARDS EXIST AT THE PRESENT TIME BY WHICH THESE STRUCTURES CAN BE JUDGED IMPARTIALLY. /AUTHOR/]]></description>
      <pubDate>Fri, 16 Sep 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/105466</guid>
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      <title>CURRENT AND FUTURE OPERATIONAL CHALLENGES OF INTERMODALISM</title>
      <link>https://trid.trb.org/View/300159</link>
      <description><![CDATA[Intermodalism has caused changes in the types of ships used to carry containers.  Ships today have capacities of 4,500 TEU (twenty-foot equivalent units).  The bridges and engine rooms have been automated, enabling crew reductions of about 50%.  Containers have evolved from lengths of 20 ft to 35, 40, 45, 48 and even 53 ft.  The standard width of containers was 96 in., but now there are 102-in. wide containers.  The height has increased from 8 ft to 9.5 ft.  The inland rail shipment of containers evolved from the use of piggyback service to double-stack service, or from carrying a maximum of 100 FEU (forty-foot equivalent units) to as many as 280 FEU as an average.  Lower rates to shippers have resulted from economies of scale and improved productivity.  Present and future challenges include labor productivity improvement, establishing a cargo cut-off time for ships, better inbound stowage, channel dredging to accommodate big ships, and on the rail side, greater tunnel and bridge clearance and on-dock or near-dock rail facilities.]]></description>
      <pubDate>Mon, 31 Jul 1989 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/300159</guid>
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    <item>
      <title>HOW HIGH IS THAT BRIDGE AHEAD?</title>
      <link>https://trid.trb.org/View/283448</link>
      <description><![CDATA[The Roadlink system, an on-board computer, keyboard and integration software, is designed to provide long-haul, irregular-route carriers a turn-key operations management system that will maximize the benefits available through Geostar Corporation.  A key advantage of Roadlink is that information will be available to fleet operators in real time, rather than on a call-in basis.  And since hardware and software are provided by Centralink, all troubleshooting can be handled through a single telephone number.  In addition to keeping track of vehicle location, speed, drivers' hours of service and fuel tax records, Roadlink will provide drivers with weather information and up-to-the minute height measurements of upcoming bridges.  Another development at Centralink is an antenna mounting system that ensures an optimal line of sight from a vehicle's Radio Determination Satellite Service (RDSS) antennas to the satellite, regardless of tractor type or configuration.  The Satellite-Linked Instrument Mount (SLIM) resembles a basket-handle type of spoiler, and is mounted as far forward on a tractor as possible.  In addition to housing a vehicle's two RDSS antennas, SLIM can also accommodate CB, cellular phone and TV antennas, and bridge-height sensors.]]></description>
      <pubDate>Wed, 31 Aug 1988 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/283448</guid>
    </item>
    <item>
      <title>PREVENTION OF VEHICLE DAMAGE ON BRIDGES</title>
      <link>https://trid.trb.org/View/203927</link>
      <description><![CDATA[Road authorities have been concerned for many years about increased damage caused to bridges by super-high loads as there are no measures by which such damage can be prevented. Besides large material damage, risks are also caused for road safety and, as collisions against underbridges also jeopardize rail traffic, railway authorities are also worried.  The national roads and waterways administration has set up a group to examine the following matters: (1) proper structure of height-indicator devices with drawings; (2) location of devices in view of the bridge and the height of installation; (3) priority of height-indicator devices; (4) construction and maintenance costs; (5) judicial principles involved in construction and in collision cases; and, (6) any other solutions. Developing various height-indicator devices formed the central part of the group's work requiring knowledge about accidents, earlier experiments and experience.  Other solutions for prevention of collision damage were examined.  (TRRL)]]></description>
      <pubDate>Thu, 28 Jun 1984 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/203927</guid>
    </item>
    <item>
      <title>LIFT SYSTEM FOR RAISING CONTINUOUS CONCRETE BRIDGES</title>
      <link>https://trid.trb.org/View/202075</link>
      <description><![CDATA[Due to road resurfacing a significant number of highway bridges throughout the nation violate underneath clearance requirements.  A bridge lifting/monitoring system was developed as one solution to this problem.  The system was designed to uniformly raise continuous 4-span/4-girder reinforced concrete deck/girder bridges.  Detailed descriptions of the lift system components along with the systems capabilities, and lift procedure are presented.]]></description>
      <pubDate>Fri, 30 Mar 1984 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/202075</guid>
    </item>
    <item>
      <title>600-TON PILES SUPPORT WEST SEATTLE FREEWAY BRIDGE</title>
      <link>https://trid.trb.org/View/196941</link>
      <description><![CDATA[Sixty 600-ton design load capacity steel pipe piles support a six-lane segmented concrete box girder main span crossing over the West Waterway in Seattle, Washington. The high level balanced cantilever bridge has a clearance of 140 feet overwater and spans 290 feet on each side of the main columns.  This is part of the $150 million, 5,700-foot-long, elevated structure for the West Seattle Freeway Bridge Replacement Project presently under construction.  The 600-ton design load and the 1,200-ton earthquake loading comprise one of the heaviest individual pile loads supporting a highway bridge structure in the United States.  The 600-ton capacity was verified during the design stage by a state-of-the-art testing program. A 36-inch diameter pipe pile was selected by the design engineer as being the most cost-effective pile foundation. The pile test program provided the information necessary for development of pile installation specifications.  Test pile driving records are believed to have assisted the contractors in preparing their bids, resulting in the overall project costs to be below the Engineer's estimate.]]></description>
      <pubDate>Fri, 30 Mar 1984 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/196941</guid>
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    <item>
      <title>DAMAGE TO LOW BRIDGES. BRIDGE HEIGHT GAUGES</title>
      <link>https://trid.trb.org/View/192294</link>
      <description><![CDATA[Since the early 1970's an increasing hazard has developed due to road vehicles or their loads striking and damaging bridges over roads.  This report covers the trials of different height gauges.  Present legislation, publicity, experience at other sites, various types of protection and other information available are reviewed to provide the background to the problem.  Six bridge sites were chosen to carry out tests on an automatic system using infra red detectors to activate diversion signs, a soft visual system using light conspicuous flaps hanging from a gantry, and a multiple message system designed to control high and overheight vehicles at arch bridges with limited headroom. The three systems were evaluated as to their effectiveness. No system was found totally effective even when used to supplement standard signing.  The main recommendations of the report are to co-ordinate methods of ranking bridges in terms of risk to allow an assessment of all protective measures on a cost effective basis.  (TRRL)]]></description>
      <pubDate>Mon, 30 Jan 1984 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/192294</guid>
    </item>
    <item>
      <title>A SURVEY AMONG LORRY DRIVERS ABOUT THE STRIKING OF LOW BRIDGES</title>
      <link>https://trid.trb.org/View/172792</link>
      <description><![CDATA[An interview survey of 497 drivers of high vehicles was conducted in 1978. Lorry drivers' knowledge of the overall height of the vehicle plus any load being carried at the time was compared with actual height measurements. Although 95 per cent of drivers interviewed claimed to know the height of their vehicle, only 185 drivers were accurate to within 3 in either side of the correct height and 73 were underestimating their vehicles' height by more than 3 in. Lorry drivers' knowledge of road signs relating to low bridges was also investigated. Seventy-two per cent of lorry drivers were fully or acceptably correct in their understanding of the road sign "headroom at hazard ahead", but only 31 per cent were correct in their understanding of the road sign "available width of headroom at hazard". Drivers were asked what they did when they had to cope with low bridges and some details of accidents involving low bridges were recorded. In addition drivers' opinions were obtained about a number of suggested ways of reducing the incidence of low bridge strikes by lorries. An infra-red detector system which indicates when a vehicle exceeds the signed height was the most favoured among the lorry drivers.  Sixty-eight per cent of the drivers interviewed thought that this system would work best. Other methods such as gongs across the road, lanes marked under bridges, words painted on the road and rumble areas were all considerably less popular.  (Author/TRRL)]]></description>
      <pubDate>Tue, 22 Dec 1981 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/172792</guid>
    </item>
    <item>
      <title>AN ERGONOMICS APPROACH TO THE PROBLEMS OF HIGH VEHICLES STRIKING LOW BRIDGES</title>
      <link>https://trid.trb.org/View/159722</link>
      <description><![CDATA[The incidence of high vehicles striking low bridges has increased considerably since about 1970.  Now, between 400-500 such accidents occur every year.  This study investigated two possible reasons for the accidents.  These were drivers' knowledge of theeir vehicle heights, and drivers' understanding of the low bridge warning signs. Drivers' opinions of ways of preventing the accidents were also obtained.  Only 12% of drivers were correct in their estimate of their vehicle height and 27% were within 3 in (76 mm) of the correct height.  The majority of drivers made estimates which erred on the "safe" side.  21% of drivers did not understand the road sign that shows "headroom at hazard ahead".  The ways of preventing high vehicles striking low bridges most popular with the drivers were those which provided them with information which was most directly relevant, i.e, whether or not the vehicle would get safely under the bridge.  (Author) (TRRL) completion of the inner ring road and the north east and north west radial roads is particularly important.]]></description>
      <pubDate>Fri, 06 Feb 1981 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/159722</guid>
    </item>
    <item>
      <title>THE ANGERED BRIDGE, GOTHENBURG</title>
      <link>https://trid.trb.org/View/153817</link>
      <description><![CDATA[In order to relieve the recently constructed Tingstad tunnel, a ring road is being constructed around Gothenburg. On the northern section, angered bridge connects the residential areas to the north-east with three industrial estates.  The bridge is 930 M long with a maximum span of 129 M, has a width of 16.95 M with three traffic lanes and separate pedestrian and cycle lanes.  It has a 3% gradient rising to the east.  The maximum clearance for shipping is 50 M.  The invitation to tender specified that the bridge should be slender and should not dominate the landscape. The successful tender for a prestressed concrete structure came to skr. 28.1 million.  Foundation conditions are variable, maximum depth to rock being 70 M.  This is overlain by 40 M moraine, 10-20 M gravel and up to 20 M clay.  Piling was difficult due to blocky moraine deposits; there are 160 piles per pier foundation.  Some piles needed 10000 blows to set.  Average length of pile is 38 M. Abutments are founded on rock.  The superstructure consists of box girders.  There are hinges between piers 3-4 and 5-6. The superstructure was constructed by cantilevering out from the piers. (TRRL)]]></description>
      <pubDate>Wed, 19 Nov 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/153817</guid>
    </item>
    <item>
      <title>CONSTRUCTION OF THE NAVIGATION SPANS OF THE RIO NITEROI BRIDGE, BRAZIL</title>
      <link>https://trid.trb.org/View/141091</link>
      <description><![CDATA[The paper describes the fabrication, assembly and erection of the large steel box girders forming the navigation spans of the Rio Niteroi Bridge.  The centre span of 300 M is the largest girder span in the world.  The twin box girder cross-section carries six lanes of traffic on a steel orthotropic deck topped with 60 mm of surfacing.  The all-welded box girders were assembled at the site at ground level at an assembly area which had a water frontage enabling large girder sections to be floated to the navigation channels in the centre of Guanabara Bay.  The largest sections thus transported were the side spans, each 292 M long and weighing 2250 t.  The side spans were landed on temporary ring girders surrounding the pier bases.  The jacking up of the side spans was the second heaviest bridge jacking operation in the world and was carried out twice. The 176 M section for the centre of the bridge, weighing 3400 t, was used initially as a pontoon for carrying the side spans; it was then lifted up from water level some 67 M by jacking up tension members hanging from the already erected steelwork.  The smaller link spans, each 44 M long, were lifted from the water using conventional blocks and tackle.  The paper discusses the shop and site welding of the 13100 t of steel in the spans, some 8000 t of which was grade 55e to BS 4360.  The effects of the erection scheme on the design of the permanent works are also described, including the stress-relieving effects of the scheme on the welded steelwork. /TRRL/]]></description>
      <pubDate>Sat, 29 Sep 1979 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/141091</guid>
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