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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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    <item>
      <title>Neural rendering for autonomous driving</title>
      <link>https://trid.trb.org/View/2752082</link>
      <description><![CDATA[This thesis addresses the challenge of building digital twins for autonomous driving: data-driven virtual replicas of real-world scenes that faithfully reproduce sensor observations while remaining editable for counterfactual testing. The first contribution is NeuRAD, a neural simulator that jointly reconstructs camera and lidar data from recorded driving sequences. By explicitly modeling key sensor characteristics, including rolling shutter effects, beam divergence, and non-returning lidar rays, NeuRAD achieves state-of-the-art rendering fidelity across multiple autonomous driving datasets. The second contribution is SplatAD, which replaces the volumetric representation of NeuRAD with 3D Gaussian primitives and purpose-built rasterization algorithms. This yields real-time rendering of both camera and lidar data at competitive fidelity, while reducing training and inference times by an order of magnitude, making large scale simulation substantially more practical. The third contribution is IDSplat, which eliminates the reliance on human-annotated 3D bounding boxes required by both NeuRAD and SplatAD. By combining vision foundation models with classical matching and estimation techniques, IDSplat achieves annotation-free dynamic scene reconstruction that generalizes zero-shot to new datasets. The fourth contribution is a highly parallelizable GPU algorithm for constructing large-scale 3D Voronoi and power diagrams, addressing a key computational bottleneck in mesh-based neural rendering and enabling larger, higher-fidelity scene representations. Finally, the thesis investigates the real-to-sim gap: the discrepancy between how autonomous systems perceive real and rendered sensor data. Through large-scale evaluation, correlations between rendering quality and downstream perception performance are identified, and fine-tuning strategies are developed that improve model robustness to simulation artifacts without compromising real-world performance. Together, these contributions advance the state of neural simulation for autonomous driving, bringing scalable, high-fidelity virtual testing closer to practical deployment]]></description>
      <pubDate>Fri, 07 Aug 2026 08:36:47 GMT</pubDate>
      <guid>https://trid.trb.org/View/2752082</guid>
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    <item>
      <title>An oblique impact test rig for next-generation European bicycle helmet testing standard</title>
      <link>https://trid.trb.org/View/2752024</link>
      <description><![CDATA[This project has developed a highly repeatable oblique impact test rigaligned with the forthcoming European standards. The infrastructure incorporates the new EN 17950 headform, which, in comparison to the Hybrid III counterparts, possesses high biofidelity (in terms of friction of coefficient and moment of inertia) to ensure an accurate physical interaction between the human head and the helmet liner during an impact. To guarantee realistic tribological behaviour, the headform's surface coefficient of friction was rigorously calibrated and verified using a standardized Capstan-based methodology. Utilizing this advanced platform, an empirical evaluation of eight representative bicycle helmets available on the Swedish market was conducted. The selected cohort deliberately encompassed diverse price points and integrated rotational protection technologies. The testing matrix subjected the helmets to oblique impacts against a 45° angled anvil at four specific cranial locations (termed as pXR, pYR, nYR, and pZR) and two initial velocities (6.0 m/s and 7.6 m/s). Impact kinematics were recorded using an embedded 6-degree-of-freedom wireless sensor system. To bridge the gap between external kinematics and internal injury risk, high-fidelity finite element analysis was employed to evaluate tissue-level responses during helmeted impacts, specifically quantifying the maximum principal strain within the brain. The eleven experimental kinematics-based injury metrics and maximum principal strain of the brain are highly dependent on the initial impact velocity and the specific impact location. As anticipated, increasing the impact velocity from 6.0 m/s to 7.6 m/s consistently increased the values of all linear, rotational, and combined injury metrics. The simulations revealed a distinct stratification in protective performance: helmets equipped with rotational protection systems consistently attenuated peak maximum principal strain more effectively than conventional designs across all tested configurations. This project not only resolves a national deficit in safety testing infrastructure but also establishes a robust empirical framework to guide consumer choices, inform future European standardization, and incentivize the helmet industry toward continuous technical advancement, thereby reinforcing Sweden's leading position in traffic injury prevention.]]></description>
      <pubDate>Fri, 07 Aug 2026 08:35:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/2752024</guid>
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    <item>
      <title>Verification methods for robust driver assist system performance, VERDAS</title>
      <link>https://trid.trb.org/View/2752020</link>
      <description><![CDATA[The goal of the project was to support significantly improved road safety for automated vehicles by developing physical and virtual verification methods for the efficient development of Driver assistance systems to take care of a larger part of all accident scenarios and that the safety function performance should be robust in real-world accident scenarios. The background to the project was that even if retrospective studies show reduction of seriously injured and killed it still shows limitations despite many years of development of Driver assistance systems and verification methods e.g. in Euro NCAP. Euro NCAP has identified those limitations in Vision 2030 and the first introduction of verification methods for robust Driver assistance systems will be introduced in Euro NCAP rating 2026. To enable the verification of a larger number of all accident scenarios, virtual testing is required to complement physical testing. The rating will include a wider range of real-world accident test scenarios and robustness layers with e.g. traffic environments and other road users. This project had a specific focus on accident scenarios with vulnerable road users. The project decided in the beginning of the project to narrow the focus to Pedestrian scenarios with Straight Crossing Path (SCP) accident scenarios. The purpose of this research project was to support Euro NCAP with proposals of robustness physical and virtual test methods for Driver assistance systems for Euro NCAP 2026. The test methods are based on deep analysis of field data to take care of a larger part of all accident scenarios.]]></description>
      <pubDate>Fri, 07 Aug 2026 08:35:35 GMT</pubDate>
      <guid>https://trid.trb.org/View/2752020</guid>
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    <item>
      <title>ABS-effektivitet på cyklar för säkrare och tryggare cykling : framtagning av en provmatris</title>
      <link>https://trid.trb.org/View/2666543</link>
      <description><![CDATA[Cyclists are a vulnerable group in traffic, where single accidents account for a significant proportion of accidents, and slippery surfaces are often a common contributing factor. Information about whether and how cyclists braked before losing-of-control (LoC) is often missing. To better understand LoC situations, new naturalistic data are needed that capture the cyclist's behavior a few seconds before the accident. For motorcycles, anti-lock braking system (ABS) is already mandatory within the EU, and several studies have shown that the ABS technology reduces both the number of accidents and the accident severity. For bicycles and e-bikes, however, only few studies exist. Injuries caused by front-wheel-lock, over-the-handlebar accidents, and panic braking on slippery surfaces indicate that ABS could improve traffic safety. The project aims, first, to investigate the potential of ABS for bicycles, particularly e-bikes, since the BikeModel study found that e-bikes increase cyclists' average cycling speed by 7-31 percent and overall cycling speed by about 3.6 km/h compared to regular bicycles. Moreover, an e-bike is approximately 6-10 kg heavier than a standard bicycle, with a total weight of around 20-25 kg for a typical e-bike model. Combined, higher speed and greater weight mean that more braking force is required to achieve the same deceleration as on a regular pedal bicycle. The second aim of the project is to propose a testing strategy that can be used to systematically evaluate ABS technology. Based on the discussions during the workshop the author proposes a stepwise test strategy with three levels: basic tests on asphalt and gravel, intermediate-level tests involving panic braking on slippery surfaces, and advanced scenarios including evasive maneuvers and downhill braking.]]></description>
      <pubDate>Thu, 05 Feb 2026 08:33:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/2666543</guid>
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    <item>
      <title>Measurements of wear and resuspension from individual vehicles : WeaRS</title>
      <link>https://trid.trb.org/View/2666536</link>
      <description><![CDATA[It is well known that particles in air affect both climate and health. Due to more stringent regulations of exhaust emissions, more efficient engines and more hybrid and electric vehicles in the vehicle fleet, the exhaust-related particle emissions from road traffic have steadily decreased. Conversely, the emissions of wear particles from tires, brakes, and roadway as well as resuspension of road dust, today unregulated, is increasing in pace with a growing vehicle fleet. Quantitative data on non-exhaust emissions (NEE) is scarce. In this project a novel method was develop and tested for measuring and characterising the emissions of resuspension/wear particles from individual vehicles in real-world traffic. Measurements were conducted at the VTI road simulator, at a test track and in real traffic. The estimated emissions were characterised with respect to vehicle weight, speed, and road dust load and its characteristics, as well as compared to emissions resulting from the NORTRIP emission model.]]></description>
      <pubDate>Thu, 05 Feb 2026 08:33:29 GMT</pubDate>
      <guid>https://trid.trb.org/View/2666536</guid>
    </item>
    <item>
      <title>Self-driving bikes for more realistic development and testing of systems for bike safety, part 2</title>
      <link>https://trid.trb.org/View/2666513</link>
      <description><![CDATA[The goal of this project has been to develop self-driving bikes that will be used for validating safety functions for manual and self-driving vehicles. The bikes are intended to be used in tests together with vehicles and will be designed to behave as realistically as possible with the ability to wiggle, curve taking, and having a realistic roll angle in these maneuvers. Test drives with a dummy have been performed at Asta Zero and at the airfield in Vårgårda. More information at https://sites.google.com/view/autobikes/project-overview.]]></description>
      <pubDate>Thu, 05 Feb 2026 08:33:03 GMT</pubDate>
      <guid>https://trid.trb.org/View/2666513</guid>
    </item>
    <item>
      <title>Dynamic shear rheometer for rheological investigation of bitumen in road applications : the impact of measurement technique</title>
      <link>https://trid.trb.org/View/2666494</link>
      <description><![CDATA[The rheological properties of bituminous binders tested with a dynamic shear rheometer (DSR) as a function of loading time and temperature can more accurately represent real road situations with rising traffic loads and densities combined with climatic change. This method is more effective than traditional methods such as measuring the softening point and penetration. Complex shear modulus and phase angle which describe the materials' viscoelastic response at a given frequency and temperature can be measured using a DSR following European standard EN 14770. Even though EN 14770 primarily describes the preparation and conditioning of specimens, various steps in the DSR testing setup result in nonconformity. Therefore, an investigation was conducted to review several areas of test method practices and the underlying impact on results. Data from round-robin tests on bitumen types 20/30 in 2018 and polymer-modified bitumen 45/80-55 in 2019 and 2020, as well as from laboratory experiments on neat bitumen and modified bitumen with wax, SBS, and filler were analysed. The variability in testing conditions and how the testing conditions may affect the measures, as well as the precision of the test technique, are statistically examined. After that, a two-level, three-factor experimental design was used to investigate the effects of the oven setting temperature (HT), bonding temperature (BT) to the rheometer, and trimming state of the specimen on outcomes. Finally, DSR and conventional tests were used to examine the stiffening impact of the fillers when added to bitumen (mastics).]]></description>
      <pubDate>Thu, 05 Feb 2026 08:32:44 GMT</pubDate>
      <guid>https://trid.trb.org/View/2666494</guid>
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    <item>
      <title>Relating Binder Parameters to Asphalt Mixture Cracking Tests in the Laboratory</title>
      <link>https://trid.trb.org/View/2635619</link>
      <description><![CDATA[Since the inception of the Performance-Graded (PG) asphalt binder specification, G*sin delta has been used as an intermediate temperature parameter intended to be related to fatigue cracking distress. Cracking can be load related and non-load related, so it is important to understand how asphalt binder properties can relate to both types of cracking distress in mixtures. Although G*sin delta seems to have value when characterizing the stiffness of an aged binder, it mostly misses the relaxation component important to asphalt binders as they age and become more brittle. To address this, an experiment was designed with the hypothesis that mixtures made with asphalt binder having worse relaxation properties will have poorer laboratory cracking performance when tested at an equistiffness temperature than mixtures made with asphalt binder having better relaxation properties. Mixture specimens were tested to evaluate stiffness and cracking performance. Results from the cracking tests were related to current and proposed parameters for use in the PG asphalt binder specification. Findings from the experiment indicate that cracking is not easily defined by one test or test condition. When temperature is removed as a factor, the IDEAL-CT test appears to capture relaxation as indicated by asphalt binder properties.]]></description>
      <pubDate>Tue, 20 Jan 2026 11:16:31 GMT</pubDate>
      <guid>https://trid.trb.org/View/2635619</guid>
    </item>
    <item>
      <title>Evaluating the Effectiveness of Geosynthetics in Reinforced Asphalt Overlays Under Different Temperature Conditions</title>
      <link>https://trid.trb.org/View/2635355</link>
      <description><![CDATA[Reflective cracking in Hot-Mix Asphalt (HMA) overlays is a common problem caused by traffic and thermal loads. These loads lead to bending, shear stresses, and increased brittleness at lower temperatures, resulting in significant maintenance costs. Geosynthetic interlayers have proven effective in delaying reflective cracking by redirecting crack propagation horizontally and dissipating energy. A laboratory test method employing the Crack Widening Device that was developed at Ecole de Technologie Superieurs (ETS) to assess geosynthetic crack resistance and differentiate load-displacement curves among various reinforced bituminous interfaces was used in this research work. The study aimed to evaluate the influence of temperature and geosynthetic placement on asphalt interfaces using bi-layer bituminous specimens with geotextile or geo-composite, compared to reference specimens. Consistent application of hot mix to both layers simulated real working conditions. Temperature significantly impacts geosynthetic effectiveness. At around 40°C, reduced asphalt viscosity can cause delamination, while at -20°C, brittleness induces contraction. At moderate room temperature (25 ± 2°C), Paving Fabric (PF) showed superior performance, with better energy dissipation and stiffness retention compared to geo-composite and control specimens. Geosynthetics placed one-third from the bottom yielded the best results, particularly with PF.]]></description>
      <pubDate>Tue, 20 Jan 2026 11:16:31 GMT</pubDate>
      <guid>https://trid.trb.org/View/2635355</guid>
    </item>
    <item>
      <title>Enhanced Acceptance Testing of Recovered Asphalt Binder for the Betterment of the Road Building Industry</title>
      <link>https://trid.trb.org/View/2619130</link>
      <description><![CDATA[Sensitive and reproducible tests for measuring rheological and failure parameters of asphalt binders are indispensable for selecting superior performing materials in road construction, ultimately securing a high level of sustainability. Two remarkably successful approaches involve the use of the Double-Edge-Notched Tension (DENT) and the Extended Bending beam Rheometer (EBBR) test methods to measure material properties that are influenced by flow characteristics. In Ontario, binders are evaluated based on their Limiting Low Temperature Performance Grade (LLTPG) and grade loss from the EBBR test, as well as their critical Crack Tip Opening Displacement (CTOD) determined by using the DENT test. Although the implementation of these tests has doubled and tripled projected service lives. for newly constructed pavements, they require a significant amount of extracted and recovered binder and take considerable time and effort to complete. Therefore, this study explores the potential of more practical methods using the Dynamic Shear Rheometer (DSR). Results show that limiting phase angle temperatures, T (30deg) and T (45deg), and their difference, DeltaT(cdelta), can be used as alternatives to EBBR and DENT properties. correlations with field performance are expected to improve when binders are properly conditioned prior to testing to account for both structural equilibration and oil exudation phenomena.]]></description>
      <pubDate>Tue, 20 Jan 2026 11:16:31 GMT</pubDate>
      <guid>https://trid.trb.org/View/2619130</guid>
    </item>
    <item>
      <title>Erfassung der subjektiven Sicherheit von ungeschützten Verkehrsteilnehmern. Erstellung eines Leitfadens</title>
      <link>https://trid.trb.org/View/2603391</link>
      <description><![CDATA[Der Mangel an Grundlagenforschung in Bezug auf das Thema "Subjektive Sicherheit von Radfahrenden" soll behoben und der Fachwelt ein oder mehrere geprüfte Erhebungsinstrumente zur Verfügung gestellt werden. Auf Basis der Erkenntnisse soll in zukünftigen Forschungsprojekten die subjektive Sicherheit von Radfahrerinnen und Radfahrern nach heutigem Wissensstand möglichst reliabel und valide erfasst werden können. Ziel ist die Ergänzung der bisherigen Arbeiten im Rahmen des Forschungsprojekts  82.778/2021 (siehe 01912150) und die Einbeziehung von  Expertinnen und Experten zum Thema im Rahmen von Workshops. Es sollen Erhebungsinstrumente zur subjektiven Sicherheit für Forschungs- und Feldstudien entwickelt und gegebenenfalls optimiert werden und es soll ein BASt-Leitfaden mit dem Stand des Wissens, Empfehlungen zur Erhebung der subjektiven Sicherheit von Radfahrenden und mit den Erhebungsinstrumenten zusammengestellt werden. ABSTRACT IN ENGLISH: The research project aims to address the lack of basic research on the topic of ‘subjective safety of cyclists’ and to provide experts with one or more tested survey instruments. Based on the findings, future research projects should be able to measure the subjective safety of cyclists as reliably and validly as possible according to the current state of knowledge. The aim is to supplement the work carried out to date as part of the research project 82.778/2021 (see 01912150), and the involvement of experts. A guide is to be compiled containing the current state of knowledge, recommendations for surveying the subjective safety of cyclists and the survey instruments.]]></description>
      <pubDate>Wed, 24 Sep 2025 08:54:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/2603391</guid>
    </item>
    <item>
      <title>Jämförande provning flisighetsindex och LT-index : svensk ringanalys 2022</title>
      <link>https://trid.trb.org/View/2598666</link>
      <description><![CDATA[This comparative testing of the Flakiness index (SS-EN 933-3. and Shape index (SS-EN 933-4. was initiated by the Swedish Association for Test Methods of Road Materials and Pavements. The purpose was to study variations between laboratories, obtain precision data from this interlaboratory comparison, and examine the impact of variations, for example, in equipment and execution. The analysis was conducted by the participants in the spring of 2022. The 49 participants received two materials each in the respective sizes 8/11 mm and 16/32 mm. The results are reported as averages, standard deviations, counts, counts outside two standard deviations from the mean, and precision data in the form of repeatability and reproducibility. Outliers have been assessed based on "two standard deviations" and more statistically according to Mandel's, Grubbs', and Cochran's tests. Results as averages and standard deviations are minimally affected with or without outliers, therefore all results have been included in the calculations. Most variations in equipment and handling do not result in significant differences except for whether the sieves are shaken by hand or machine. Machine shaking is also done in almost all cases with circular sieves. Machine shaking results in approximately 0,5 percentage points higher results, which rounded off can give an increase of one unit (1 percentage point).]]></description>
      <pubDate>Fri, 12 Sep 2025 10:19:51 GMT</pubDate>
      <guid>https://trid.trb.org/View/2598666</guid>
    </item>
    <item>
      <title>Pensieve perception : uncertainty, language, and novel views for autonomous driving</title>
      <link>https://trid.trb.org/View/2598611</link>
      <description><![CDATA[Autonomous driving stands as one of the most complex challenges in artificial intelligence and robotics. These systems are expected to provide safe and efficient navigation across diverse and dynamic environments. This thesis addresses critical obstacles in the development of autonomous driving technologies by focusing on three primary areas: uncertainty estimation in object detection, reduction of annotation requirements through self-supervised learning, and the creation of scalable, realistic simulations via neural rendering. First, we introduce a novel framework for uncertainty estimation in object detection, leveraging the Random Finite Set formalism to provide a principled approach for training and evaluating probabilistic object detectors. This framework enables practitioners to better understand the capabilities and limitations of object detectors, and effectively design and deploy safer and more reliable systems. Second, we present LidarCLIP, a self-supervised learning method designed to bridge the gap between lidar point clouds and language understanding. By aligning lidar data with the CLIP embedding space through image-point cloud pairs, LidarCLIP learns semantic scene understanding without the need for costly human annotations. This approach has the potential to significantly reduce the dependency on labeled data, accelerating the development and deployment of autonomous driving systems. Last, we develop NeuRAD and SplatAD, advanced neural rendering techniques for joint camera and lidar simulation. NeuRAD offers a state-of-the-art neural simulator that facilitates scalable and sensor-realistic closed-loop simulations, while SplatAD enhances this capability by improving both visual quality and computational efficiency. These methods pave the way for scalable validation and testing of autonomous driving systems in diverse and rare scenarios, facilitating comprehensive safety assessments. Collectively, this thesis addresses existing challenges in autonomous driving and opens up new avenues for future research in building safe and reliable autonomous driving systems at scale.]]></description>
      <pubDate>Fri, 12 Sep 2025 10:19:03 GMT</pubDate>
      <guid>https://trid.trb.org/View/2598611</guid>
    </item>
    <item>
      <title>Entwicklung und Erprobung von Testszenarien zur KI-basierten Beurteilung von Fahrverhalten unter psychoaktivem Substanzeinfluss</title>
      <link>https://trid.trb.org/View/2582443</link>
      <description><![CDATA[Zur Erfassung und Beurteilung der Leistungsfähigkeit von Fahrer/-innen ist die experimentelle Überprüfung im Realverkehr der Goldstandard. Untersuchungen zur Fahrleistung unter psychoaktivem Substanzeinfluss von Alkohol, Medikamenten oder Drogen finden vornehmlich auf Testgeländen statt, auf denen mittels instrumentierter Messfahrzeuge verkehrssicherheitsrelevante Fahrvariablen registriert werden. Die Fahrleistungsbewertung muss ganzheitlich erfolgen, sodass ein Profil aus zahlreichen Leistungsparametern geschaffen wird, das alle verschiedenen Ebenen des Fahrverhaltens abbildet (globale Fahrleistungsratings, teilautomatisierte Registrierung und Klassifikation von Fahrfehlern, automatisierte Berechnung einschlägiger taktischer und operationaler Fahrparameter). Eine besondere Herausforderung spielt die Festlegung, ab wann eine Abweichung von einer sogenannten Normalfahrt als verkehrssicherheitsrelevant einzustufen ist. Ziel des Projektes ist die Entwicklung von Verkehrsszenarien (Testszenarien), mit denen sich erste Leistungseinbußen beim Fahren unter psychoaktivem Substanzeinfluss, die mit einem Verkehrssicherheitsrisiko einhergehen, KI-basiert auf der Basis fahrdynamischer Daten ermitteln lassen. Die Verkehrsszenarien sind zu erproben und ihre Anschlussfähigkeit auf weitere Fragestellungen ist sicherzustellen. ABSTRACT IN ENGLISH: Experimental testing in real traffic is the gold standard for recording and assessing driver performance. Studies on driving performance under the influence of psychoactive substances such as alcohol, medication or drugs are primarily conducted on test tracks, where driving variables relevant to road safety are recorded using instrumented test vehicles. Driving performance must be assessed holistically so that a profile can be created from numerous performance parameters that reflects all the different levels of driving behaviour. The aim of the project is to develop traffic scenarios (test scenarios) that can be used to determine initial performance impairments when driving under the influence of psychoactive substances, which pose a risk to road safety, using AI and based on driving dynamics data. The traffic scenarios are to be tested and their applicability to other issues is to be ensured.]]></description>
      <pubDate>Mon, 22 Sep 2025 03:21:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/2582443</guid>
    </item>
    <item>
      <title>Experience with inflatable friction rock bolts on the Cross River Rail project</title>
      <link>https://trid.trb.org/View/2563091</link>
      <description><![CDATA[Friction rock bolts offer a significant advantage over grouted bolts in that they do not require grouting and thus provide immediate ground support upon installation. Inflatable friction bolts were developed around 40 years ago, with various versions of this type of bolt now offered by several manufacturers. The bolt is unique in that it is expanded with high pressure water during installation. This expansion generates the shear strength of the frictional interface with the rock. Pull testing was performed on inflatable friction bolts both prior to and during construction of the Cross River Rail project in Brisbane, which commenced construction in early 2020 with tunnelling completed at the end of 2021. Bolts for initial  site trials were partially sleeved such that only a short length of bolt was  inflated. This detail allowed the frictional interface between the bolt shaft and borehole wall to be tested to relatively high shear stresses, and thus allowed measurement of the ultimate geotechnical bond capacity. The test methodology also involved measurement of the axial displacement of the bolt relative to the applied load. This permitted bond shear stiffness to be assessed. The test methodology also involved measurement of the axial displacement of the bolt relative to the applied load. This permitted bond shear stiffness to be assessed. This is a parameter utilised in numerical analysis and design of tunnel support and relates to the rate of load transfer between the rock bolt and surrounding rock mass. Both pre-production and production pull tests were completed in rock mass types including Neranleigh Fernvale Group, Brisbane Tuff and Aspley Formation bedrock. The measured bond strength values confirmed design assumptions that were based on a comprehensive literature review. The results allowed the contractor to proceed with procurement of the plant and materials needed to install the bolts with the confidence that they were an appropriate ground support element for the anticipated ground conditions. Advantages and limitations of this type of bolt are discussed, together with durability considerations, installation methods, production rates, construction challenges, test methods, and back-analysis of key design parameters.]]></description>
      <pubDate>Tue, 10 Jun 2025 14:50:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/2563091</guid>
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