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    <title>Transport Research International Documentation (TRID)</title>
    <link>https://trid.trb.org/</link>
    <atom:link href="https://trid.trb.org/Record/RSS?s=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" 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>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
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    <item>
      <title>Optimisation of gradation based on fractal dimension for large-size graded crushed stone</title>
      <link>https://trid.trb.org/View/2618001</link>
      <description><![CDATA[To improve the mechanical properties of large particle size graded crushed stone mixture and obtain the optimal grading. By using different design methods to obtain the grading of large particle size graded crushed stone, the maximum dry density test, CBR penetration test, static pressure test, and cyclic repeated compaction test were conducted on the large particle size graded crushed stone samples. Finally, fractal theory was introduced to quantitatively calculate the grading of large particle size graded crushed stone, and the fractal dimension of large particle size graded crushed stone was obtained. The relationship between the fractal dimension of large particle size graded crushed stone and density, CBR value, compressive strength, and deformation resistance was analyzed through grey correlation analysis. The experimental results show that large particle size graded crushed stone has better skeleton performance than conventional graded crushed stone; The density, CBR value, compressive strength, and deformation resistance of large-sized graded crushed stone are related to the grading. The skeleton dense grading ratio has stronger mechanical properties compared to the suspended dense grading and skeleton interlocking grading. And the optimal fractal dimension for the optimal configuration should be between 2.59−2.61.]]></description>
      <pubDate>Mon, 09 Feb 2026 13:55:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/2618001</guid>
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    <item>
      <title>Indicated airspeed error due to gradual blocking of pitot tube with drain hole</title>
      <link>https://trid.trb.org/View/1943821</link>
      <description><![CDATA[Problem of pitot tube blocking is persistent because even in the recent past there have been several accidents based on inaccurate information from air speed indicators. This problem was caused by a partial or complete blockage of the total pressure probes. Certain principles of blocking detection are well known. This article describes research into another principle of the gradual blocking detection of the pitot tube with drain holes. Pitot tubes with different blockage ratios were made and tested. A gradual blocking curve was described. The independence of velocity magnitude for the investigated airspeeds was found. This research shows that the drain hole design can be useful for a pitot tube blockage detection. The principle is based on another pitot tube with a larger drain hole area. Airspeed error due to gradual blocking grows faster on the other pitot tube. Gradual blocking of both pitot tubes results in a difference in indicated airspeeds, even at constant speed flight and before full blockage. This airspeed difference can warn a pilot and gives him or her a valuable time to use emergency procedures. © 2022]]></description>
      <pubDate>Mon, 27 Jun 2022 17:19:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/1943821</guid>
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    <item>
      <title>Benchmark study on slamming response of flat-stiffened plates considering fluid-structure interaction</title>
      <link>https://trid.trb.org/View/1858558</link>
      <description><![CDATA[This paper presents a benchmark study on the slamming responses of offshore structures’ flat-stiffened plates. The objective was to compare the fluid-structure interaction (FSI) simulation methodologies, modeling techniques, and established researchers' experiences in predicting slamming pressure. Three research groups employing the most common commercial software packages for numerical FSI simulations (i.e. LS-Dyna ALE, LS-Dyna ICFD, ANSYS CFX, and Star-CCM+/ABAQUS) participated in this study. Wet drop test data on flat-stiffened aluminum plates of light-ship-like bottom structures available in the open literature was utilized for validation of the FSI modeling. A summary of the experimental conditions including the geometry model and material properties, was distributed to the participants prior to their simulations. A parametric study on flat-stiffened steel plates having actual scantlings used in marine installations was performed to investigate the effect of impact velocity and plate rigidity on slamming response. The FE simulation results for the total vertical forces acting on the stiffened plates and their structural responses to those forces, as obtained from the participants, were analyzed and compared. The reliable and accurate predictions of slamming loads using the aforementioned commercial FSI software packages were evaluated. Additionally, equivalent static slamming pressures resulting in the same permanent deflections, as observed from the FSI simulations, were reported and compared with analytical models proposed by the Classification Standards DNV and existing experimental data for calculation of the slamming pressure. The study results showed that the equivalent load model depends on the water impact velocity and plate rigidity; that is, the equivalent static pressure coefficient decreases with an increase in impact velocity, and increases when impacting structures become stiffer.]]></description>
      <pubDate>Mon, 26 Jul 2021 15:47:06 GMT</pubDate>
      <guid>https://trid.trb.org/View/1858558</guid>
    </item>
    <item>
      <title>Formation mechanism of static pressure circumferential double-peak distribution in a centrifugal compressor under the action of downstream boundary</title>
      <link>https://trid.trb.org/View/1854781</link>
      <description><![CDATA[In the centrifugal compressor applied in the automobile turbochargers, the asymmetric structure of volute causes the non-uniform flow field in the impeller and compressor stall. The non-uniformity of the flow field in the compressor can be reflected by the casing-wall static pressure distribution. In this study, by removing the volute and directly imposing different simplified static pressure boundary conditions at the diffuser outlet, the formation mechanism of casing-wall static pressure circumferential double-peak distribution of the compressor is explored. It is found that the mass flow rate is redistributed at the impeller outlet due to local high static pressure induced by the volute tongue, which results in the formation of two airflow regions with high velocity in the diffuser, ultimately leading to the static pressure circumferential double-peak distribution in the diffuser and the impeller. Noted that because of the existence of the blades, the airflow regions with high and low velocity formed in the diffuser are locked within a limited range of one or more widths of the blade passage. When the number of blades in the compressor is large, the static pressure can appear as multi-peak distribution in the circumferential direction. Moreover, the result of the mass flow rate redistribution at the impeller outlet is determined by the static pressure distribution characteristics at the diffuser outlet.]]></description>
      <pubDate>Wed, 30 Jun 2021 11:58:44 GMT</pubDate>
      <guid>https://trid.trb.org/View/1854781</guid>
    </item>
    <item>
      <title>Numerical study of effects of geometric parameters on the flow and cavitation characteristics inside conical nozzle of autonomous underwater vehicles</title>
      <link>https://trid.trb.org/View/1712571</link>
      <description><![CDATA[The geometric parameters (ratio of orifice’s length to diameter, conical angle, and inner-wall roughness) of conical nozzle are investigated via computational fluid dynamic method to reveal the effect on the flow and cavitation characteristics. The variation of geometric parameters affects the distribution of the static pressure and the drag force, which in turn affects the mass flow rate at the outlet. The results indicate that the conical angle plays a dominant role in effecting the flow and cavitation characteristics. The higher the intensity of cavitation, the more notable the effect of geometric parameters on cavitation characteristics.]]></description>
      <pubDate>Tue, 23 Feb 2021 10:25:21 GMT</pubDate>
      <guid>https://trid.trb.org/View/1712571</guid>
    </item>
    <item>
      <title>Effects of Seat and Sitter Dimensions on Pressure Distribution in Automotive Seats</title>
      <link>https://trid.trb.org/View/1462686</link>
      <description><![CDATA[Seat fit is characterized by the spatial relationship between the seat and the vehicle occupant’s body. Seat surface pressure distribution is one of the best available quantitative measures of this relationship. However, the relationships between sitter attributes, pressure, and seat fit have not been well established. The objective of this study is to model seat pressure distribution as a function of the dimensions of the seat and the occupant’s body. A laboratory study was conducted using 12 production driver seats from passenger vehicles and light trucks. Thirty-eight men and women sat in each seat in a driving mockup. Seat surface pressure distribution was measured on the seatback and cushion. Relevant anthropometric dimensions were recorded for each participant and standardized dimensions based on SAE J2732 (2008) were acquired for each test seat. Regression models were effective in predicting characteristics of pressure distribution from the anthropometric variables and SAE J2732 dimensions. The resulting models may be useful to evaluate virtual fit simulations of the interaction between the seat and sitter.       ]]></description>
      <pubDate>Thu, 20 Feb 2020 09:30:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/1462686</guid>
    </item>
    <item>
      <title>Analysis of Steel Strip Reinforced Thermoplastic Pipe under Internal Pressure</title>
      <link>https://trid.trb.org/View/1498913</link>
      <description><![CDATA[Based on the three-dimensional (3D) elasticity theory, this paper presents the mechanical properties of steel strip reinforced thermoplastic, cross-section view of such pipe plastic-steel-plastic (PSP) under internal pressure. The steel strip reinforced PSP pipe consists of four layers. Mises yield criterion is introduced to predict the damage of the pipe on layer 2. Further a 3D finite element model is established in ABAQUS to compare with the theoretical model and the result shows good agreement with each other in terms of hoop stress and axial stress, which means the proposed elastic model is feasible and can be applied and updated to study the elasto-plastic properties of steel strip reinforced PSP pipe in future research, and serve as a guide to the forthcoming experiments.]]></description>
      <pubDate>Fri, 22 Jun 2018 16:40:40 GMT</pubDate>
      <guid>https://trid.trb.org/View/1498913</guid>
    </item>
    <item>
      <title>Effects of low Reynolds number on flow stability of a transonic compressor</title>
      <link>https://trid.trb.org/View/1344874</link>
      <description><![CDATA[As the aircraft cruising at high altitude over 20,000 m with subsonic speed, the Reynolds number in terms of the compressor blade becomes very low and the compressor performance decreases dramatically due to separation of boundary layer and secondary-flow. The main objective in this paper is to understand the physical mechanism by which Reynolds number affects the compressor stable range. In this paper, a series of steady and unsteady numerical simulations were carried out for a transonic compressor rotor under several conditions, which corresponded to the operations at sea level, and at high altitude. Detailed analyses of the flow visualization have exposed the different flow topologies of the complicated secondary flow. It was found that the transonic axial-flow compressor rotor used in current investigation was prone to tip stall behavior, and the complex flow mechanisms which occur near the blade tip are found to be the key factors for the limited flow stability both under high Reynolds number and low Reynolds number. Under high Reynolds number, the tip flow field was dominated by the low momentum zones generated by the interaction between tip leakage flow and incoming flow, and with the decrease of Reynolds number, the tip leakage flow was weakened and the low-momentum fluid due to the surface boundary layer separation and radial transport of low-energy fluid was dominant in the tip flow.]]></description>
      <pubDate>Fri, 20 Mar 2015 15:21:05 GMT</pubDate>
      <guid>https://trid.trb.org/View/1344874</guid>
    </item>
    <item>
      <title>GPS-Based Pitot-Static Calibration Method Using Global Output-Error Optimization</title>
      <link>https://trid.trb.org/View/917285</link>
      <description><![CDATA[Pressure-based airspeed and altitude measurements for aircraft typically require calibration of the installed system to account for pressure sensing errors such as those due to local flow field effects. In some cases, calibration is used to meet requirements such as those specified in Federal Aviation Regulation Part 25. Several methods are used for in-flight pitot-static calibration including tower fly-by, pacer aircraft, and trailing cone methods. In the 1990 s, the introduction of satellite-based positioning systems to the civilian market enabled new inflight calibration methods based on accurate ground speed measurements provided by Global Positioning Systems (GPS). Use of GPS for airspeed calibration has many advantages such as accuracy, ease of portability (e.g. hand-held) and the flexibility of operating in airspace without the limitations of test range boundaries or ground telemetry support. The current research was motivated by the need for a rapid and statistically accurate method for in-flight calibration of pitot-static systems for remotely piloted, dynamically-scaled research aircraft. Current calibration methods were deemed not practical for this application because of confined test range size and limited flight time available for each sortie. A method was developed that uses high data rate measurements of static and total pressure, and GPSbased ground speed measurements to compute the pressure errors over a range of airspeed. The novel application of this approach is the use of system identification methods that rapidly compute optimal pressure error models with defined confidence intervals in nearreal time. This method has been demonstrated in flight tests and has shown 2- bounds of approximately 0.2 kts with an order of magnitude reduction in test time over other methods. As part of this experiment, a unique database of wind measurements was acquired concurrently with the flight experiments, for the purpose of experimental validation of the optimization method. This paper describes the GPS-based pitot-static calibration method developed for the AirSTAR research test-bed operated as part of the Integrated Resilient Aircraft Controls (IRAC) project in the NASA Aviation Safety Program (AvSP). A description of the method will be provided and results from recent flight tests will be shown to illustrate the performance and advantages of this approach. Discussion of maneuver requirements and data reduction will be included as well as potential applications.]]></description>
      <pubDate>Mon, 24 May 2010 14:08:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/917285</guid>
    </item>
    <item>
      <title>Non-Linear Static Analysis of Aircraft Tire Subjected to Inflation Pressure and Ground Contact Loads Using Finite Element Analysis</title>
      <link>https://trid.trb.org/View/864118</link>
      <description><![CDATA[The pneumatic tire has been an integral part of transportation almost since its inception, yet it remains a product whose characteristics are not easily predictable or comprehensible by conventional engineering techniques. This thesis is an attempt to provide a numerical model for predicting the ground contact pressure pattern between an aircraft tire and road under static condition.]]></description>
      <pubDate>Thu, 17 Jul 2008 09:24:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/864118</guid>
    </item>
    <item>
      <title>Radiated Noise from Small Centrifugal Fans</title>
      <link>https://trid.trb.org/View/813662</link>
      <description><![CDATA[This paper describes how noise that radiated from small centrifugal fans of the same size but of different designs were measured in a semianechoic chamber. These measurements were conducted with the fans that generated different static pressures and flow velocities at the discharge. Analyses of results from the sound power levels of the noise radiated by the fans, and the corresponding static pressure and flow velocities measured at the discharge are presented in the paper. The objective of the paper is to relate fan design and operating conditions to radiated noise levels and thereby developing guidelines for the operation conditions and designs of quiet small centrifugal fans.]]></description>
      <pubDate>Thu, 26 Jul 2007 09:55:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/813662</guid>
    </item>
    <item>
      <title>Response of Conventional Steel Stud Wall Systems under Static and Dynamic Pressure</title>
      <link>https://trid.trb.org/View/766924</link>
      <description><![CDATA[This research effort focuses on the evaluation of existing design standards for cold-formed steel stud walls and the development of retrofit wall systems. Full-scale wall systems are tested under uniform static pressure using a vacuum chamber. The resistance functions obtained are used to model the dynamic behavior of the walls and to predict performance under blast conditions. This paper focuses on defining the static resistance of nonload-bearing steel stud walls with slip track connections and their performance under external explosions. Simple modifications to existing design practice have significantly improved the blast performance of the steel stud walls. Maximum blast resistance is achieved by using steel angles connected to the studs and anchored to the floor and ceiling. The static and dynamic performances of five full-scale steel stud wall systems are presented in this paper.]]></description>
      <pubDate>Fri, 02 Dec 2005 11:48:13 GMT</pubDate>
      <guid>https://trid.trb.org/View/766924</guid>
    </item>
    <item>
      <title>PREDICTION OF SEVERE EYE INJURIES IN AUTOMOBILE ACCIDENTS: STATIC AND DYNAMIC RUPTURE PRESSURE OF THE EYE</title>
      <link>https://trid.trb.org/View/748465</link>
      <description><![CDATA[The purpose of this paper is to determine the static and dynamic rupture pressures of 20 human and 20 porcine eyes.  This study found the static test results show an average rupture pressure for porcine eyes of 1.00 + or - 0.18 MPa while the average rupture pressure for human eyes was 0.36 + or - 0.20 MPa.  For dynamic loading, the average porcine rupture pressure was 1.64 + or - 0.32 MPa, and the average rupture pressure for human eyes was 0.91 + or - 0.29.  Significant differences are found between average rupture pressures from all four groups of tests (p = 0.01). A risk function has been developed and predicts a 50% risk of globe rupture at 1.02 MPa, 1.66 MPa, 0.35 MPa and 0.90 MPa internal pressure for porcine static, porcine dynamic, human static, and human dynamic loading conditions, respectively.]]></description>
      <pubDate>Fri, 14 Jan 2005 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/748465</guid>
    </item>
    <item>
      <title>SELECTED CAR SEAT STUDIES DEALING WITH STATIC PRESSURE DISTRIBUTION. IN: HUMAN FACTORS IN DRIVING AND TELEMATICS, AND SEATING COMFORT</title>
      <link>https://trid.trb.org/View/706239</link>
      <description><![CDATA[The static pressure distribution has been established by the automotive seating industry as criteria against which to evaluate automotive seats.  This paper describes a study that is based on six separate investigations that provide specific recommendations concerning the system setup, subject selection, and protocol execution.  The study showed that results are affected by the presence of pressure mats. That means that survey evaluations and static pressure distribution evaluations must be separated.]]></description>
      <pubDate>Tue, 24 Aug 2004 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/706239</guid>
    </item>
    <item>
      <title>EFFECT OF COMPACTION METHOD ON STABILITY AND SWELL PRESSURE OF SOILS</title>
      <link>https://trid.trb.org/View/122593</link>
      <description><![CDATA[TEST DATA ARE PRESENTED FOR TWO SOILS, A SILTY CLAY AND A SANDY CLAY, COMPARING THE STABILITIES AT VARIOUS WATER CONTENTS AND DENSITIES OF PARTIALLY SATURATED SAMPLES COMPACTED BY IMPACT METHODS, STATIC PRESSURE, AND KNEADING ACTION. THE STABILITIES OF SAMPLES PREPARED BY THESE THREE METHODS AND SOAKED TO NEAR SATURATION AT CONSTANT DENSITY ARE ALSO COMPARED. A POSSIBLE EXPLANATION FOR THE DIFFERENT EFFECTS OF THE COMPACTION METHODS IS SUGGESTED AND SOME OF THE DIFFICULTIES OF PREPARING SATURATED SAMPLES IN THE LABORATORY ARE DISCUSSED. DATA ARE ALSO PRESENTED COMPARING THE DEFORMATION CHARACTERISTICS IN TRIAXIAL-COMPRESSION TESTS OF SILTY-CLAY SPECIMENS PREPARED BY IMPACT, STATIC, AND KNEADING COMPACTION IN THE LABORATORY WITH THOSE OF THE SAME SOIL COMPACTED BY SHEEPSFOOT AND RUBBER-TIRED ROLLERS IN THE FIELD. A COMPARISON IS ALSO MADE OF THE STABILITY AND SWELL PRESSURES DEVELOPED AT VARIOUS DENSITIES FOR SAMPLES OF A SANDY CLAY COMPACTED BY KNEADING AND STATIC METHODS AND SUBSEQUENTLY SATURATED BY EXUDATION OF MOISTURE UNDER STATIC LOAD. THE GREAT DIFFERENCE IN TEST RESULTS OBTAINED IS ILLUSTRATED. /AUTHOR/]]></description>
      <pubDate>Sun, 15 Aug 2004 02:44:05 GMT</pubDate>
      <guid>https://trid.trb.org/View/122593</guid>
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