<rss version="2.0" xmlns:atom="https://www.w3.org/2005/Atom">
  <channel>
    <title>Research in Progress (RIP)</title>
    <link>https://rip.trb.org/</link>
    <atom:link href="https://rip.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
    <description></description>
    <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>Research in Progress (RIP)</title>
      <url>https://rip.trb.org/Images/PageHeader-wTitle-RIP.jpg</url>
      <link>https://rip.trb.org/</link>
    </image>
    <item>
      <title>Statistical Evaluation of Illinois Modified AASHTO T161 Freeze–Thaw Testing Following Laboratory Relocation</title>
      <link>https://rip.trb.org/View/2686616</link>
      <description><![CDATA[A critical way to build high-performing pavements and bridges is to evaluate a mixture’s freeze-thaw performance in the lab to ensure it meets performance parameters. The aim of this project is to calibrate and validate new equipment for freeze-thaw testing at the Illinois Department of Transportation’s (IDOT's) Central Bureau of Materials. Researchers will test aggregate samples using IDOT’s new and existing freeze-thaw equipment, ensuring the new equipment produces consistent and replicable results. They will also create calibration guidelines that will help to establish a repeatable framework when replacing future freeze-thaw testing equipment.]]></description>
      <pubDate>Wed, 01 Apr 2026 09:41:33 GMT</pubDate>
      <guid>https://rip.trb.org/View/2686616</guid>
    </item>
    <item>
      <title>Correlation of Laboratory Three-Wheel Polisher Revolutions with Roadway Accumulated-Traffic to Evaluate Laboratory Polishing of Pavements</title>
      <link>https://rip.trb.org/View/2593938</link>
      <description><![CDATA[Prior to conducting laboratory dynamic friction tests (DFTs), a three-wheel polisher is used to simulate the polishing effect of traffic on asphalt pavements. Limited research has looked at how the number of revolutions completed by a three-wheel polisher correlates with real-world cumulative traffic volume. Establishing correlations between the number of three-wheel polisher revolutions and real-world traffic volume will clarify how aggregate polishing affects pavement friction.]]></description>
      <pubDate>Thu, 28 Aug 2025 11:32:33 GMT</pubDate>
      <guid>https://rip.trb.org/View/2593938</guid>
    </item>
    <item>
      <title>Managing Vehicle-Rail Interface (VRI) Dynamics and Mechanics</title>
      <link>https://rip.trb.org/View/2446878</link>
      <description><![CDATA[The primary purpose of this study is to perform accurate dynamic measurements on a scaled roller rig designed and constructed by Virginia Tech and the Federal Railroad Administration (VT-FRA Roller Rig). The study also aims at determining the effect of naturally generated third-body layer deposits (because of the wear of the wheel and/or roller) on creep or traction forces. The wheel-rail contact forces, also referred to as traction forces, are critical for all aspects of rail dynamics. These forces are quite complex and they have been the subject of several decades of research, both in experiments and modeling. The primary intent of the VT-FRA Roller Rig is to provide an experimental environment for more accurate testing and evaluation of some of the models currently in existence, as well as evaluate new hypothesis and theories that cannot be verified on other roller rigs available worldwide.

The Rig consists of a wheel and roller in a vertical configuration that allows for closely replicating the boundary conditions of railroad wheel-rail contact via actively controlling all the wheel-rail interface degrees of freedom: angle of attack, cant angle, normal load and lateral displacement, including flanging. The Rig has two sophisticated independent drivelines to precisely control the rotational speed of the wheels, and therefore their relative slip or creepage. The Rig benefits from a novel force measurement system, suitable for steel on steel contact, to precisely measure the contact forces and moments at the wheel-rail contact.

Experimental studies will be conducted on the VT – FRA Roller Rig that involved varying the angle of attack, wheel and rail surface lubricity condition (i.e., wet vs. dry rail), and wheel wear, to study their effect on wheel-rail contact mechanics and dynamics. The wheel-rail contact is in between a one-fourth scale AAR-1B locomotive wheel and a roller machined to US-136 rail profile. A quantitative assessment of the creep-creepage measurements, which is an important metric to evaluate the wheel-rail contact mechanics and dynamics, is presented. A MATLAB routine is developed to generate the creep-creepage curves from measurements conducted as part of a broad experimental study. The shape of the contact patch and its pressure distribution have been discussed. An attempt is made to apply the results to full-scale wheels and flat rails. The research results will help in the development of better simulation models for non-Hertzian contact and non-linear creep theories for wheel-rail contact problems that require further research to more accurately represent the wheel-rail interaction.
]]></description>
      <pubDate>Tue, 29 Oct 2024 15:30:15 GMT</pubDate>
      <guid>https://rip.trb.org/View/2446878</guid>
    </item>
    <item>
      <title>Michigan Cone Penetrometer Test Calibration</title>
      <link>https://rip.trb.org/View/2143711</link>
      <description><![CDATA[The Michigan Department of Transportation (MDOT) purchased Cone Penetration Test (CPT) equipment in 2019 to better define the geotechnical conditions at project sites.
To date, MDOT has used the CPT on 12 sites including the M-66 Monroe Creek Crossing. One year of CPT data has been
collected on projects that were also drilled using traditional techniques. A total of 50-55 CPT soundings exists alongside
traditional soil borings with visual descriptions and blow counts. Some grain size distribution and other lab tests have been
conducted from the soil boring samples. MDOT has graphed some of the data on published soil type behavior charts to note
preliminary correlations. However, more statistical comparison is needed to calibrate the Michigan CPT test and identify
procedures that should be followed to produce and interpret Michigan soil data reliably. In addition, MDOT could benefit from a
standardized procedure that stores data in the Data Interchange for Geotechnical and Geoenvironmental Specialists (DIGGS)
data storage format and provides automated output that assists with risk-based design. Further identifying site variability may
help with appropriate site characterization and design savings.]]></description>
      <pubDate>Mon, 27 Mar 2023 12:01:25 GMT</pubDate>
      <guid>https://rip.trb.org/View/2143711</guid>
    </item>
    <item>
      <title>Continuous Friction Measurement (SCRIM) to Support Implementation of Improved Pavement Management Systems</title>
      <link>https://rip.trb.org/View/2062417</link>
      <description><![CDATA[This research involves advance use of Sideway-Force Coefficient Routine Investigation Machine (SCRIM) through demonstration projects and implementation support for improved pavement management systems.]]></description>
      <pubDate>Tue, 15 Nov 2022 16:17:39 GMT</pubDate>
      <guid>https://rip.trb.org/View/2062417</guid>
    </item>
    <item>
      <title>	NEXTGEN Concrete - Tests of the Future: Thermal Profile</title>
      <link>https://rip.trb.org/View/1986939</link>
      <description><![CDATA[The objectives of this project are the following: (1) Evaluate the performance of the Calmetrix F-Cal 8100 device for this analysis; (2) Develop the materials and dimensional specifications for a testing apparatus assembled from available off-the-shelf items; (3) Develop a temperature profile analysis protocol or recommend commercially available software; (4) Develop an FDOT calibration/baseline mix recipe for use by all in a “comparative” approach. The heat generation profile of a proposed mix compared to the baseline mix. (5) Develop preliminary threshold for mass concrete exclusion based on the results of the developed analysis protocol]]></description>
      <pubDate>Wed, 29 Jun 2022 15:07:06 GMT</pubDate>
      <guid>https://rip.trb.org/View/1986939</guid>
    </item>
    <item>
      <title>NEXTGEN Concrete - Tests of the Future: Shrinkage</title>
      <link>https://rip.trb.org/View/1976255</link>
      <description><![CDATA[The objectives of this project are the following: 
(1) Design and fabricate the most advantageous test apparatus that will accommodate concrete with #57 while adapting to AASHTO T334. 
(2) Define the dimensions and specifications for the new test apparatus. 
(3) Create the resulting Florida Test Method. 
(4) Use the new apparatus to assess Florida Department of Transportation (FDOT) approved mix designs over the spectrum of shrinkage risk. 
(5) Develop a shrinkage profile analysis protocol or recommend commercially available software. 
(6) Develop an FDOT calibration/baseline mix recipe for use by all in a “comparative” approach and the shrinkage profile of a proposed mix compared to the baseline mix. 
(7) Set preliminary threshold for bridge deck concrete exclusion based on the results of the developed analysis protocol.]]></description>
      <pubDate>Fri, 03 Jun 2022 10:32:17 GMT</pubDate>
      <guid>https://rip.trb.org/View/1976255</guid>
    </item>
    <item>
      <title>Evaluations of FHWA Research &amp; Technology Program Projects. Evaluation of the Asphalt Binder Quality Tester (TFPE-01)</title>
      <link>https://rip.trb.org/View/1957072</link>
      <description><![CDATA[The FHWA Research and Technology (R&T) Evaluation Program seeks to assess and communicate the benefits of FHWA's R&T efforts; ensure that the organization is expending public resources efficiently and effectively; and build evidence to shape and improve policymaking. Beginning in 2019, FHWA requested that the Transportation Research Board be directly involved in managing evaluations of selected projects. 
The asphalt binder quality test (ABQT) is a rapid testing device that measures deflection and recovery in a sample of asphalt binder and then estimates the performance grade of the binder sample. Binder quality is an important component of asphalt quality, affecting the quality and performance of asphalt pavement. Compared with most existing binder testing equipment, the ABQT is smaller, requires less calibration, and uses smaller sample volumes, making it more portable and easier to use. The ABQT has the potential to provide test results more rapidly at a project site or in a state testing laboratory. This could allow for an increased number of samples tested, which can help State DOTs and project managers better detect out-of-specification binder before it is paved. 
For project TFPE-01, "Asphalt Binder Quality Tester", RTI International was tasked to evaluate the process by which ABQT research was selected and conducted. The effort also included an evaluation of activities to promote the adoption of ABQT by state departments of transportation along with an assessment of barriers to adoption of the ABQT by public- and private-sector entities. A quantitative estimate of the potential benefits of the ABQT was also developed.]]></description>
      <pubDate>Fri, 27 May 2022 12:41:07 GMT</pubDate>
      <guid>https://rip.trb.org/View/1957072</guid>
    </item>
    <item>
      <title>SPR-4623:  Improved Light Weight Deflectometer Test (LWD) and Analysis</title>
      <link>https://rip.trb.org/View/1898768</link>
      <description><![CDATA[This project aims to establish a specialized testing program for the determination of maximum LWD deflection criteria in lieu of field test sections. The deliverables are: (1) Laboratory LWD equipment, which will be integrated into the Indiana Department of Transportation (INDOT) Division of Research & Development (R&D) specialized testing program; (2) a manual of standard procedures for operating and calibrating the laboratory LWD equipment; and (3) an addendum to the manual of laboratory LWD standard operation and calibration procedures that specifies standard procedures for the interpretation and analysis of laboratory LWD test data.
]]></description>
      <pubDate>Mon, 20 Dec 2021 15:14:45 GMT</pubDate>
      <guid>https://rip.trb.org/View/1898768</guid>
    </item>
    <item>
      <title>A Multiple Camera System to Determine the Absolute Volume of Soil Specimens During Dynamic Triaxial Testing (yr 1)</title>
      <link>https://rip.trb.org/View/1868764</link>
      <description><![CDATA[Triaxial tests have been widely used to evaluate stress-strain behavior for geomaterials. In the past few decades, several methods have been developed to measure the volume changes of unsaturated soil specimens during triaxial tests. Literature review indicates that all existing methods can only measure relative soil volume and it remains a major challenge for researchers to measure the absolute volume changes of soil specimens during dynamic triaxial testing. The research will develop a computer vision/photogrammetry-based multiple camera system for measuring the absolute volume change for soil specimen during dynamic triaxial testing. Methodology will be developed to analyze the videos taken from multiple cameras by combining deep-learning techniques and modern close-range photogrammetry. Three-dimensional models of the soil specimen with high accuracy will be constructed using the videos and will be compared and validated using different methods. Post-processing algorithms will be developed to automatically calculate the absolute volume, titling, eccentricity, as well as localized displacement/strains at any arbitrary locations. This method for 3D reconstruction will provide us a non-contact, high accuracy, low cost, and easy-to-operate tool for absolute volume measurements for soil specimen during dynamic triaxial testing.]]></description>
      <pubDate>Tue, 27 Jul 2021 18:19:37 GMT</pubDate>
      <guid>https://rip.trb.org/View/1868764</guid>
    </item>
    <item>
      <title>Synthesis of Information Related to Highway Practices. Topic 53-18. Moisture Measurement for Pavement Foundations and Slopes</title>
      <link>https://rip.trb.org/View/1853032</link>
      <description><![CDATA[Accurate and timely moisture measurement of soils, aggregates, and recycled materials is critical to properly compacting these materials. There are numerous methods for measuring the moisture content of the soil; some are laboratory-based, and some are done in-situ. The objective of this synthesis is to document state department of transportation (DOT) practices for field and laboratory moisture measurement for pavement foundations and slopes.

Information for this study was gathered through a literature review, a survey of state DOTs, and follow-up interviews with selected DOTs. Case examples of three state DOTs provide additional information on practices for moisture measurement.

Claudia Zapata and Saleh Alothman, Arizona State University, collected and synthesized the information and wrote the report. The members of the topic panel are acknowledged on page iv. This synthesis is an immediately useful document that records practices that were acceptable within the limitations of the knowledge available at the time of its preparation. As progress in research and practice continues, new knowledge will be added to that now at hand.]]></description>
      <pubDate>Mon, 17 May 2021 22:39:40 GMT</pubDate>
      <guid>https://rip.trb.org/View/1853032</guid>
    </item>
    <item>
      <title>RES2019-12: Utilization of Accelerated Pavement Tester (APT) for New Materials and Pavement Structure Research</title>
      <link>https://rip.trb.org/View/1851959</link>
      <description><![CDATA[Accelerated pavement test (APT) is defined as the controlled application of a prototype wheel loading at the
appropriate load to the full-scale pavement structure, which is used to determine the structural responses and 
performance of the pavement in a short period. Inverted pavement is an unconventional type of flexible pavement 
structure. In this pavement structure, an unbound aggregate base (UAB) with a low initial modulus is layered
between two stiffer layers, an asphalt concrete layer (AC) and a cement-treated base layer (CTB). This project
presents two rounds of APT tests on full-scale inverted pavements. In the first-round APT, a comparison study on 
the rutting performance between the conventional and inverted pavement structures was presented. In addition, 
the inverted pavements with different thicknesses of UAB and CTB were studied. Significant permanent 
deflections were observed in all three pavement lanes after 100k passes of APT. Based on the measured 
deformation, the inverted pavement structure outperformed the conventional pavement in terms of the final surface 
deformation. And the inverted pavement with a thicker CTB layer had a better performance than the inverted 
pavement with a thicker UAB layer. Based on the overall pavement conditions, the inverted pavement can be 
regarded as an alternative to the conventional flexible pavement, and asphalt mixture layer thickness can be 
reduced during construction. In the second round of APT, the effect of geogrids in the inverted pavement was 
investigated. The polypropylene geogrids were installed in the full-scale inverted pavements and different 
locations of geogrids were discussed as well. After 150k passes of APT, the rutting performance was compared 
and studied. The results show that the geogrids could improve the rutting resistance of the inverted pavement, but 
the effect of geogrids depended on the location in the UAB layer. In this study, the geogrids placed at the upper 
1/3 upper layer of UAB displayed the best rutting performance among the three pavement lanes due to its constraint 
for the aggregates. However, when the geogrids were installed at the 2/3 thickness of the UAB, the rutting 
performance of the inverted pavement structure became worse since its position experienced little tension and 
could not take effect. Therefore, the location of geogrids plays a vital role in improving the rutting resistance of 
the inverted pavement.]]></description>
      <pubDate>Tue, 11 May 2021 17:00:50 GMT</pubDate>
      <guid>https://rip.trb.org/View/1851959</guid>
    </item>
    <item>
      <title>Development of an Automated and Rapid Conditioning and Testing Device for Cracking and Rutting</title>
      <link>https://rip.trb.org/View/1749082</link>
      <description><![CDATA[State highway agencies (SHAs) are currently facing multiple challenges. Three such challenges involve addressing (a) the asphalt pavement cracking and rutting distresses that cost taxpayers billions of dollars annually, (b) the loss of the workforce and the skills associated with the workforce, and (c) laboratory safety concerns to prevent worker injury. Many SHAs are addressing the cracking and rutting problems by implementing a balanced mix design method to design durable mixes. However, the lack of workforce and workforce skills hinder such efforts. Additionally, primary safety concern in the laboratory is preventing worker injury often associated with the hot asphalt, large masonry saws, high-force testing machines, and toxic chemicals typically found in an asphalt material testing lab. Automation of certain processes can alleviate all these safety concerns by reducing the number of employees exposed to the different hazards. The automated robotic device developed in this project attempts to address these issues. The device is named asphalt mixture automated testing system with zero intervention (AMAZE).  The device comprises four main components: (a) an air void measurement unit, (b) a temperature conditioning unit, (c) a material testing unit, and (d) a robotic arm. Furthermore, AMAZE can automatically perform different tests to measure four essential properties of asphalt mixtures: (a) air voids, (b) indirect tensile strength, (c) Ideal cracking tolerance index, and (d) Ideal rutting tolerance index. A comparisons of test results measured by AMAZE versus laboratory technicians was made in terms of air voids, cracking tolerance index (CTIndex), and rutting tolerance index (RTIndex), respectively. The asphalt mixture properties measured by AMAZE are comparable to those measured by laboratory technicians. The outcomes of this research project are the AMAZE device and a step-by-step implementation plan for DOT.]]></description>
      <pubDate>Wed, 04 Nov 2020 11:27:44 GMT</pubDate>
      <guid>https://rip.trb.org/View/1749082</guid>
    </item>
    <item>
      <title>Development of In-Situ Cyclic Borehole Shear Soil Test Device</title>
      <link>https://rip.trb.org/View/1664454</link>
      <description><![CDATA[In this project, a Cyclic Borehole Shear Test (CBST) device was developed to enable rapid in situ measurement of cyclic behavior and monotonic shear strength properties of the soil. The CBST is unique in its ability to measure the parameters in the soil’s natural setting, under cyclic loading, and in a matter of minutes whereas present laboratory techniques can take several weeks. By testing the soil in situ, the device saves time and money, while reducing effects of soil sample disturbance which can significantly affect laboratory test results. Based on the results of several field testing trials, numerous refinements and modifications were made to the system that included the physical testing apparatus inserted into the borehole, the electronic and pneumatic measurement and control system, and the software control program. Comparisons of the field CBST results to those of conventional laboratory cyclic direct simple shear tests demonstrated that the device can measure meaningful cyclic behavior of soils in situ. Further research will be pursued to more rigorously relate the measured displacements to shear strains in the soil surrounding the borehole, and to explore applications of the device to in situ measurement of the liquefaction behavior of soils. With further research, the device has the potential to fundamentally transform the presently empirical techniques used in practice for assessment of soil liquefaction resistance into a more mechanistic physics-based framework. 

The final report is available. ]]></description>
      <pubDate>Mon, 04 Nov 2019 21:02:36 GMT</pubDate>
      <guid>https://rip.trb.org/View/1664454</guid>
    </item>
    <item>
      <title>In-situ Scour Testing Device</title>
      <link>https://rip.trb.org/View/1358562</link>
      <description><![CDATA[The objective of this research is to prove or disprove the viability of such an in-situ scour testing device for use as a foundation design aid by the highway engineering community. The field device for the proposed study could consist of a water jet directed vertically downward into the soils that are to support the bridge pier foundations.  The jet would be calibrated through physical model testing and computer simulation to produce the predicted scour depth in a sand-bed channel for the design hydraulic conditions and proposed pier geometry.  The water jet would be run until equilibrium conditions are reached in the resulting scour hole, or until some maximum period of time has elapsed (such as the expected cumulative time the foundation will be exposed to the design discharge over the life of the bridge).  The in-situ soils would thereby be exposed to the energy necessary to develop the scour depth, as predicted by the currently used equation. Any equilibrium or maximum scour depth resulting from a field test that is less than the predicted depth for a sand-bed channel would be attributable to the erosion-resistant characteristics of the in-situ soils. It is envisioned that this scour-testing device would be used for foundation analysis and design in a manner similar to present-day soil borings in that several tests would be conducted across the channel and floodplain area to be occupied by a proposed new or replacement bridge.  The scour hole information resulting from the field test(s) would be used, in conjunction with the subsurface soil boring information, to adjust the design scour depth predicted by the equations for sand-bed channels, as appropriate, for the actual soil conditions at the bridge site. The Turner-Fairbanks Highway Research Center (TFHRC) Hydraulics Laboratory will collaborate on this proposed research and will provide Lab capabilities and technical assistance.]]></description>
      <pubDate>Tue, 23 Jun 2015 01:02:32 GMT</pubDate>
      <guid>https://rip.trb.org/View/1358562</guid>
    </item>
  </channel>
</rss>