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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=PHNlYXJjaD48cGFyYW1zPjxwYXJhbSBuYW1lPSJkYXRlaW4iIHZhbHVlPSJhbGwiIC8+PHBhcmFtIG5hbWU9InN1YmplY3Rsb2dpYyIgdmFsdWU9Im9yIiAvPjxwYXJhbSBuYW1lPSJ0ZXJtc2xvZ2ljIiB2YWx1ZT0ib3IiIC8+PHBhcmFtIG5hbWU9ImxvY2F0aW9uIiB2YWx1ZT0iMCIgLz48L3BhcmFtcz48ZmlsdGVycz48ZmlsdGVyIGZpZWxkPSJpbmRleHRlcm1zIiB2YWx1ZT0iJnF1b3Q7U3VzcGVuZGVkIHN0cnVjdHVyZXMmcXVvdDsiIG9yaWdpbmFsX3ZhbHVlPSImcXVvdDtTdXNwZW5kZWQgc3RydWN0dXJlcyZxdW90OyIgLz48L2ZpbHRlcnM+PHJhbmdlcyAvPjxzb3J0cz48c29ydCBmaWVsZD0icHVibGlzaGVkIiBvcmRlcj0iZGVzYyIgLz48L3NvcnRzPjxwZXJzaXN0cz48cGVyc2lzdCBuYW1lPSJyYW5nZXR5cGUiIHZhbHVlPSJwdWJsaXNoZWRkYXRlIiAvPjwvcGVyc2lzdHM+PC9zZWFyY2g+" rel="self" type="application/rss+xml" />
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    <language>en-us</language>
    <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>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>Dynamic performance analysis of suspended monorail vehicles under various operating conditions</title>
      <link>https://trid.trb.org/View/2587077</link>
      <description><![CDATA[This paper presents the impact of various operating conditions on the dynamic performance of suspended monorail vehicles through simulations with focusing on vehicle speed, curve radius, gradient and crosswind. A multi-body dynamic model of a two-car train is developed by incorporating the effect of track beams under crosswind conditions using a flexible track beam model to construct a wind-vehicle-bridge coupling model. To improve computational efficiency, a parameter batch processing method is used for the numerical simulation. The results show that under curved ramp conditions, the combined effects of centrifugal and gravitational forces lead to reducing the lateral stability as compared to regular curved conditions. In crosswind conditions, increasing wind speed intensifies lateral force. However, the vehicle's vertical stability remains excellent across all conditions due to the high vertical damping of the suspension system. This study supports the application of suspended monorail systems in mountainous regions.]]></description>
      <pubDate>Fri, 24 Oct 2025 16:53:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/2587077</guid>
    </item>
    <item>
      <title>Effectiveness of the Use of Suspended Structures in Seismic Areas</title>
      <link>https://trid.trb.org/View/2407845</link>
      <description><![CDATA[In high-rise construction, suspended structures of buildings and structures for various purposes are widely used, which can be implemented in one way or another. Meanwhile, in the practice of earthquake-resistant construction, there are still no recommendations for the use of these structures in earthquake prone areas due to their lack of knowledge. The article analyzes the existing design proposals for the implementation of suspended structures, including for seismic areas, and presents some results of computational studies of these structures under seismic impact. The analysis of the effectiveness of the using suspended structures in earthquakes was carried out by comparing the natural period of oscillations of buildings and the stresses in the load-bearing elements of the systems. The parameters of the computed models were determined in the SCAD computing complex by the finite elements method. The initial results show that the use of suspended structures can increase the natural period of oscillations of buildings and reduce the seismic load in the elements of the system. It is shown that under certain seismic impacts, additional elements of high-rise buildings’ seismic protection systems should be provided for the considered design solutions, ensuring their stability in case of earthquakes.]]></description>
      <pubDate>Fri, 21 Mar 2025 16:02:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/2407845</guid>
    </item>
    <item>
      <title>Calculation and testing approaches of the kinematic envelope for suspended monorail vehicles</title>
      <link>https://trid.trb.org/View/2213819</link>
      <description><![CDATA[The line-side clearance gauge has a significant influence on the economy and operational safety of suspended monorail transit systems, for which there are currently no relevant specific standards or specifications. The important basis for determining the line-side clearance gauge is the kinematic envelope of the vehicle, while few studies have been conducted on its calculation or testing approaches currently. In this paper, the kinematic envelope calculation formulas are derived for a typical suspended monorail vehicle based on geometry and force analyses, then according to the proposed formulas, the special motion posture of suspended monorail vehicle is revealed and its occurring mechanism is analyzed in detail. Furthermore, a full-scale field test is conducted to verify the derived formulas, which shows the tested motion posture is in good agreement with that analyzed by the formulas. Finally, the effect of key parameters on the kinematic envelope is studied based on the formulas, indicating that appropriately reducing the rotation angle of the bolster can effectively decrease the kinematic envelope without sacrificing ride comfort. These results can be directly used to determine the kinematic envelope, or even as a reference for establishing standards for the line-side clearance gauge of suspended monorail in the future.]]></description>
      <pubDate>Mon, 25 Sep 2023 14:46:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2213819</guid>
    </item>
    <item>
      <title>Effect of the combined centre of gravity height on the ride comfort of suspended monorail train under crosswinds</title>
      <link>https://trid.trb.org/View/2225942</link>
      <description><![CDATA[The combined centre of gravity (CCOG) height of a suspended monorail train may have a certain influence on the centrifugal forces acting on the train under crosswinds, and changes in centrifugal forces will further affect the dynamic interactions among the crosswind, the vehicle and the bridge subsystem. To investigate the effect of CCOG height on the dynamic behaviour of the train, this paper proposes an improved wind-vehicle-bridge coupling dynamics model considering the CCOG height for the suspended monorail system, in which the uneven passenger weight distribution is simulated with various vehicle parameters, and the aerodynamic wind forces acting on the running vehicles and bridge are simulated considering the effect of resultant wind yaw angle. The influences of passenger number, wind velocity, and vehicle speed on the dynamic behaviours of suspended monorail trains are also explored. The results indicate that the suspended monorail train has a certain self-balancing ability due to its unique structure type, which causes the lateral responses of the car body to attenuate with the increasing car weight. In addition, it is conservative to not consider the effect of CCOG height in the lateral ride comfort evaluation of the suspended monorail train subject to crosswinds.]]></description>
      <pubDate>Fri, 22 Sep 2023 09:08:17 GMT</pubDate>
      <guid>https://trid.trb.org/View/2225942</guid>
    </item>
    <item>
      <title>Experimental and Numerical Study on the Hydrodynamic Performance of Suspended Curved Breakwaters</title>
      <link>https://trid.trb.org/View/2065641</link>
      <description><![CDATA[The purpose of breakwaters is to protect the ports, beaches, or beach facilities from strong waves and storms, as they help establish calm inside the port and thus achieve safety for ships and ease of operation. This paper presents an experimental and numerical study of unconventional alternatives to the vertical breakwater in order to evaluate the hydrodynamic performance of the proposed models. Two proposed cases for a semi-submerged breakwater were selected in the form of a half-pipe section with an inside diameter of 20 cm and a thickness of 1 cm. Case (a) was of the concave type of semicircular breakwater, while case (b) was of the convex type. Numerical modeling FLOW 3D was used to construct numerous scenarios for numerical simulation of the proposed breakwaters. The obtained results indicates that, when comparing the wave transmission coefficient (Kt) and its reflection coefficient (Kr) with the relative water depth (h/L), the transmission coefficient decreased with the relative height of the wave, while the reflection coefficient was completely reversed. In case (a), Kt was less than in case (b) at a range of 10% to 15%, while Kr in case (a) was bigger than in case (b) at a range of 5% to 10%. When the wave hit the breakwater, it was reflected back as its energy is dissipated in less water depth and its speed decreases as it approaches the port. The velocity of the wave decreases as it approaches the bottom, which means that the wave is affected by the depth of the water, i.e. the lower the water depth, the lower the wave velocity. Case (a) was more efficient and effective in wave dissipation, current velocity, and bed stability than case (b), so it is recommended to use case (a) due to its effi in protecting coastal areas and generating electricity.]]></description>
      <pubDate>Tue, 24 Jan 2023 09:29:34 GMT</pubDate>
      <guid>https://trid.trb.org/View/2065641</guid>
    </item>
    <item>
      <title>Investigation on the Detrimental Wavelength of Track Irregularity for the Suspended Monorail Vehicle System</title>
      <link>https://trid.trb.org/View/1998179</link>
      <description><![CDATA[Track irregularity is a crucial factor influencing the running safety and ride comfort of the suspended monorail-vehicle system. This paper puts an emphasis on the exploration of the detrimental wavelengths of track irregularities for this system. Firstly, the suspended monorail vehicle model with 52 degrees of freedom is modelled by adopting multi-body dynamics theory, where the nonlinear characteristics of tyre and stop structure are considered. Based on the random nature of vehicle-track interactions, the sixth grade track irregularity PSD of U.S. railways is taken as excitation of the driving and guiding wheels in the dynamic computations. Then the characteristic wavelengths are analysed according to the dynamic responses of typical indices of the suspended monorail vehicle by the average smooth periodogram method. On this basis, the coherence theory is employed to emphatically expose the amplitudes-wavelengths relationships between track random irregularities and accelerations of car-body, wheel-rail forces, respectively. Finally, the most sensitive wavelengths of track irregularities can be further determined for the suspended monorail vehicle system. The dynamic results show that the detrimental wavelengths which significantly affect the wheel-rail forces are in the range of 1.5 m and 6~17 m, and those for the car-body accelerations are mainly about 2 m and 6 m. This research offers a reference to the maintenance and management of the suspended monorail vehicle-track system.]]></description>
      <pubDate>Sat, 14 Jan 2023 17:11:59 GMT</pubDate>
      <guid>https://trid.trb.org/View/1998179</guid>
    </item>
    <item>
      <title>Quantitative Composition of Drag Forces on Suspended Pipelines from Submarine Landslides</title>
      <link>https://trid.trb.org/View/1891728</link>
      <description><![CDATA[The impact forces of submarine landslides (i.e., non-Newtonian fluids) on oil and gas pipelines, especially the most dangerous drag force, are of great significance in the design of deep-water pipelines. The drag force is composed of two parts: the pressure drag force and the frictional drag force. However, previous studies have not quantified their proportion and magnitude, and thus it is highly difficult to analyze their evolution characteristics and mechanisms in detail. In this paper, a methodology to quantitatively obtain the pressure and frictional drag forces of submarine landslide-ambient water–pipeline interaction using computational fluid dynamics (CFD) is first proposed. Second, under four typical Reynolds number conditions, homogeneous fluidized submarine landslides impacting suspended pipelines applied by two boundary conditions (i.e., free slip and no-slip wall boundary conditions on the pipeline surface) are systematically simulated, respectively. Third, the quantitative relationship between the total, pressure, and frictional drag force coefficients is established, and the variation of their characteristic values with changing Reynolds number is analyzed. Finally, the evolutionary mechanism of the frictional drag force is explained by the change in the tangential stress of the landslide in the boundary layer on the pipeline surface, and the variation mechanism of the pressure drag force with changing Reynolds number is elucidated by the boundary layer separation, streamline evolution, and distributed pressure variation around the pipeline, which provides a theoretical basis for submarine pipeline design.]]></description>
      <pubDate>Wed, 01 Dec 2021 09:36:13 GMT</pubDate>
      <guid>https://trid.trb.org/View/1891728</guid>
    </item>
    <item>
      <title>Parameter Identification of Main Cables of Cable Suspension Structures Based on Vibration Monitoring of Cable: Methodology and Experimental Verification</title>
      <link>https://trid.trb.org/View/1765436</link>
      <description><![CDATA[This paper focus on parameter identification of the main cables of cable suspension structures. Based on the dynamic stiffness theory, an inverse analysis characteristic function (IAC function) for identifying the main cable parameters (such as cable tension, moment of inertia, cable length, and mass per unit length) is established. This function allows for the consideration of cable flexural rigidity, sag, inclination, and additional lumped masses sustained by the suspender. The effects of the cable tension and moment of inertia on the IAC function are investigated via a numerical method. On this basis, a method for identifying the two parameters based on the peak-ridges of the IAC function is proposed. The method comprehensively utilizes measured multimode frequencies. It is unnecessary to determine the fundamental frequency and frequency order. A 20-m real cable test with suspended lumped masses is conducted to verify the correctness of the proposed methods. With the increase in the weight of suspended lumped masses, the advantages of the proposed method are more obvious. For operational cable tension less than 50% of the cable breaking tension, the cable moment of inertia is less affected by suspended lumped masses.]]></description>
      <pubDate>Fri, 21 May 2021 10:57:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/1765436</guid>
    </item>
    <item>
      <title>Researches on the resonance of a new type of suspended monorail vehicle-bridge coupling system based on modal analysis and rigid-flexible coupling dynamics</title>
      <link>https://trid.trb.org/View/1757134</link>
      <description><![CDATA[This paper introduces a new type of suspended monorail developed in China with the advantages of both German and Japanese monorails. The FE (finite element) model of the bridge is built in Ansys and coupled with the multibody dynamic model of the vehicle in the UM (Universal Machine). software. FIALA formula is used to construct the tire model. Then, the vehicle-bridge coupling system of the new type suspended monorail is set up and simulated with Park method. The result of the modal analysis and vehicle-bridge coupling simulation draw the same conclusion that the span of the stiffeners could result in the resonance of the vehicle system, which is due to the coupling of the frequencies of the natural modes of the car body and bogie with that for vehicle passing through stiffeners. Through the multibody dynamic simulation of the vehicle-bridge coupling system, the modes of the bridge at the frequencies of 5–10, 15–25 and 30–40 Hz are easily excited when the vehicle passes through the bridge. The three constraint modes and free modes of the bridge are similar in these frequency ranges.]]></description>
      <pubDate>Mon, 28 Dec 2020 10:13:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/1757134</guid>
    </item>
    <item>
      <title>Field measurement of the dynamic responses of a suspended monorail train–bridge system</title>
      <link>https://trid.trb.org/View/1727434</link>
      <description><![CDATA[This work presents an integrated and large-scale field measurement of the dynamic responses of a suspended monorail train–bridge system, which is rarely reported. This experimental train uses a high-capacity lithium battery for the operation. The maximum running speed of the train is up to 60 km/h. The experimental line was constructed on a full-scale steel bridge composed of a straight section, curved sections with different horizontal radiuses and a slope section of 60‰. First, the train–bridge dynamic responses under different conditions are extracted based on the field test. Then, the car-body accelerations under different train speeds and bridge sections are analysed in detail, and the running stability of the vehicle is assessed by adopting the Sperling index. By comparing the dynamic responses of the train–straight bridge interaction and the train–curved bridge interaction, some significant discrepancies and interesting phenomena could be found. Subsequently, based on the test data, the vertical rotation angles of the beam end and the dynamic amplification factors of the bridge displacements under different vehicle speeds and bridge sections are obtained, and then the vibration levels of the bridge under different conditions are evaluated. Finally, by analysing the frequency spectra of the dynamic responses, the dominant frequencies of the acceleration signals of this monorail vehicle and bridge subsystems are revealed; in addition, the sensitive wavelengths that influence the running stability of the vehicle are found. These measurement results may provide valuable guidance for the design of the suspended monorail system and numerical model validation.]]></description>
      <pubDate>Thu, 10 Sep 2020 09:50:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/1727434</guid>
    </item>
    <item>
      <title>Simulating the Role of Axial Flow in Stay Cable Vibrations via a Perforated Wake Splitter Plate</title>
      <link>https://trid.trb.org/View/1554469</link>
      <description><![CDATA[Cable-stayed bridges have become progressively popular since 1955, mainly because of their modest requirement on ground anchorage condition, efficient use of structural material, higher stiffness, and economy compared to suspension bridges. The inclined and/or yawed orientation of bridge stay cables results in the formation of secondary axial flow on the leeward side of cable surface, which is believed to be one of the contributing factors exciting some unique wind-induced cable vibration phenomena. To clarify the role of axial flow in triggering aerodynamic instability of stay cables, a numerical study has been conducted to indirectly examine the axial flow effect via a perforated splitter plate placed along the central line of a circular cylinder wake. Results show that the presence of a perforated wake splitter plate would play a similar role as the axial flow in affecting the strength of von Kármán vortex shedding. Reductions on the fluctuating amplitude of the instantaneous lift and drag, as well as the mean drag, are also observed, which would ultimately affect the aerodynamic response of the studied cylinder.]]></description>
      <pubDate>Mon, 15 Oct 2018 09:39:06 GMT</pubDate>
      <guid>https://trid.trb.org/View/1554469</guid>
    </item>
    <item>
      <title>Wind Tunnel Test Study on Pipeline Suspension Bridge via Aeroelastic Model with π Connection</title>
      <link>https://trid.trb.org/View/1549759</link>
      <description><![CDATA[Pipeline suspension bridges are narrow and wind sensitive. There is a lack of research on the mechanical performance of pipeline suspension bridges under wind load, especially under the action of gorge wind. This paper studies the aerodynamic stability of the typical pipeline suspension bridge under the action of wind load by conducting a wind tunnel test of a full-bridge aeroelastic model. Setting a π connection to replace and simulate the core beam stiffness avoids the impact of the core beam on the flow pattern of wind, making the wind-induced dynamic response results obtained from the test more like the practical situation. The results of the measurements of the model dynamical characteristics indicate that the structural dynamic characteristics of the full-bridge aeroelastic model is similar to that of the prototype. The test results show that under various operating conditions, the typical pipeline suspension bridge in the paper has sufficient aerodynamic stability in both a boundary-layer wind field and a turbulent flow field. Under various testing conditions and wind speeds, no flutter, galloping, or other aerodynamic instabilities occur, and no lateral deformation, divergent torsion, or other static instabilities occur. There are no clear vortex-induced vibrations in the lateral, vertical, and torsional directions of the model main beam.]]></description>
      <pubDate>Fri, 05 Oct 2018 17:16:29 GMT</pubDate>
      <guid>https://trid.trb.org/View/1549759</guid>
    </item>
    <item>
      <title>Reimagining Transportation - Base Case Calculations on Flying Aerial Tram System</title>
      <link>https://trid.trb.org/View/1494508</link>
      <description><![CDATA[Rapid and significant changes are emerging in the automobile industry including the prominence of electric cars, self-driving vehicles, and significant reductions in personal car ownership; for which current infrastructure and public transit are less than optimal. This paper presents base case calculations on a low-cost high-performance "flying train" infrastructure using a 1.5 inch (38 mm) zipline-type guideway offering a synergy with these emergences. Base case calculations identify system viability, lane capacities exceeding four lanes of an interstate highway, and topics requiring further development. These topics include: a) airfoil-type vehicle shapes and modes of operation to attain lift-to-drag ratios of at least 4.0 and up to 12.0, b) operational logistics to attain capacities with spacing as low as two vehicle/train lengths, and c) a method to periodically relieve guideway (zipline) tension due to the additive nature of drag forces of sequential vehicles on the guideway. Base case approaches are presented to allow continuous guideway cables that are unobstructed for about 90% of their circumferences and zero-lead-time vehicle-controlled switching with linear motor guideways; these are fourth and fifth topics for advancement. In an aerial-tram configuration with linear motors pulling the vehicle along a stationary zipline-type guideway, it is possible to convert a significant portion of the vehicle drag to lift. This "free" lift is proportional to velocity squared and suggests that flying train configurations are a natural/synergistic evolution of guideway transit systems operating at velocities greater than about 180 mph (290 km/h).]]></description>
      <pubDate>Thu, 25 Jan 2018 09:35:13 GMT</pubDate>
      <guid>https://trid.trb.org/View/1494508</guid>
    </item>
    <item>
      <title>Finite Element Analysis of Cable-Stayed Strands’ Failure Due to Fire</title>
      <link>https://trid.trb.org/View/1373944</link>
      <description><![CDATA[The failure of one structural element may lead to the failure of the other structural components where ultimately result in the collapse of the large sections or the entire structure. The progressive collapse of the structures have been mainly investigated for buildings. However, cable failure in cable-stayed bridges may cause catastrophic consequences due to the progressive collapse. This is also crucial in part given the importance of bridge infrastructure in transporting people and the goods across the country and the key role that they play in contributing towards the nation’s economy. In design process of the cable-stayed bridges, the possibility that the loss of one cable might be leading to the collapse of the entire structure is often overlooked. This is particularly due to the structural redundancy considerations and the high safety factors in design of the structural components for these bridges. In this paper, the effects of a hypothetical fire and the thermal gradient propagation along a pre-stressed cable is studied using non-linear finite element modeling and analyses. For this purpose, the possible fire intensities and durations are studied in order to determine their effects on the strength losses in pre-stressed cables using finite element method. Results of this research could be used as basis for investigation of structural failure of cable-stayed/suspended systems.]]></description>
      <pubDate>Tue, 24 Nov 2015 09:27:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/1373944</guid>
    </item>
    <item>
      <title>Bring It Down Slowly: Controlled Demolition of a Deteriorated Suspended-Concrete Ceiling above an Active Urban Highway</title>
      <link>https://trid.trb.org/View/1350910</link>
      <description><![CDATA[The John B. Hynes Veterans Memorial Convention Center (Hynes) in Boston, Massachusetts, spans over the Massachusetts Turnpike (Turnpike), which carries eight lanes of traffic to and from the heart of the city. A 4 in. thick suspended reinforced-concrete-ceiling slab constructed in the early 1960s comprised a total of 42,000 sq ft (weighing about 1,000 tons) and separated the underside of the Hynes from the Prudential Center Tunnel (Tunnel) below. The owner, the Massachusetts Convention Center Authority, maintained the slab and performed regular maintenance, rehabilitation, and repairs. Over a 50 yr life, the slab deteriorated due to corroding reinforcement, and had effectively reached the end of its useful life. Removal, however, required construction sequencing that worked around limited nightly lane closures and limited weekend tunnel shutdowns. This paper discusses how the team effectively managed limited roadway access and tight working conditions to prepare the slab for removal, the controlled-demolition approach, and challenges encountered throughout the project.]]></description>
      <pubDate>Wed, 29 Apr 2015 09:07:29 GMT</pubDate>
      <guid>https://trid.trb.org/View/1350910</guid>
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