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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>Study on the Influence Law of Tunnel Primary-Support Arch Frame on Rock-Bolt Support Function</title>
      <link>https://trid.trb.org/View/2772593</link>
      <description><![CDATA[This study reviews the development of research on systematic-rock-bolt effectiveness in soil tunnels and clarifies the mechanism of rock-bolt inefficiency. Field statistics show that rock-bolt axial forces in soil tunnels are generally low or even compressive, especially at the arch crown, indicating limited contribution to overall stability. Comparative analysis further suggests a strong correlation between arch-frame support and rock-bolt inefficiency. Numerical simulations and physical model tests were conducted to investigate the influence law and mechanism of arch frames on rock-bolt mechanical behavior. Results show that, compared with the bolt-only scheme, the combined bolt-and-arch-frame scheme reduces bolt axial force by about 90%, and some crown bolts become compressive under shallow-burial conditions. The main mechanism is that the high stiffness of the arch frame restrains surrounding-rock deformation, thereby reducing the relative displacement required to mobilize bolt axial force; under high lateral pressure, the arch-shaped structure also transfers load toward the crown and alters the local stress state. Within the investigated parameter range, the inhibitory effect becomes stronger as the surrounding-rock grade decreases. Although arch frames effectively control surrounding-rock stability in soil tunnels, they weaken bolt performance, with the most pronounced inhibition at the spandrel. Differently from previous studies mainly focused on field observations or single-condition analysis, this paper establishes a multilevel evidence chain for systematic-rock-bolt inefficiency in soil tunnels by combining field statistics, numerical simulation, and physical model tests, thereby providing a new analytical perspective for optimizing combined support systems.]]></description>
      <pubDate>Thu, 03 Sep 2026 09:08:04 GMT</pubDate>
      <guid>https://trid.trb.org/View/2772593</guid>
    </item>
    <item>
      <title>Performance prediction and parametric study of the combined axial-centrifugal compressor</title>
      <link>https://trid.trb.org/View/2696122</link>
      <description><![CDATA[Axial and centrifugal compressors are essential components in gas turbine engines, effectively serving various applications such as aircraft propulsion, marine and land transportation, and power generation. A combined axial-centrifugal compressor stands out as an effective solution, harnessing the advantages of both compressor types. This research delivers a thorough examination of the energy loss correlations associated with these compressors. A carefully selected configuration for the combined compressor is established, leading to the development of a one-dimensional (1D) mean line model. This robust model is employed to accurately predict the performance of the axial, centrifugal, and combined axial-centrifugal compressors. The predictions generated by this model align remarkably well with experimental data from a gas turbine engine operating line. The average discrepancies in pressure ratio and isentropic efficiency predictions for the axial compressor are impressively low at 0.6% and 4.5%, respectively. For the centrifugal compressor, the average differences are also minimal, sitting at 3.4% for pressure ratio and 3.5% for efficiency. Furthermore, the average discrepancy in pressure ratio prediction for the combined compressor reaches just 3.4%. Additionally, the performance curves for the axial, centrifugal, and combined compressors are calculated utilizing the developed model. Finally, an in-depth parametric study is conducted to systematically investigate how various factors such as the solidities of the axial rotor and stator, the axial length of the impeller, and the tip clearance values of the axial rotor and impeller impact the performance of the combined compressor.]]></description>
      <pubDate>Fri, 31 Jul 2026 09:23:51 GMT</pubDate>
      <guid>https://trid.trb.org/View/2696122</guid>
    </item>
    <item>
      <title>Torsional behavior of semi-parallel wire cables under axial tension: An analytical algorithm</title>
      <link>https://trid.trb.org/View/2685133</link>
      <description><![CDATA[The coupled tension-torsion behavior of semi-parallel wire cables (SPWCs) is critical to the construction safety and in-service performance of cables and hangers in long-span bridges. Based on Costello’s elastic theory for wire ropes and Love’s theory for spatial curved rods, this study proposed an analytical model to characterize the coupled tension-torsion behavior of SPWCs and developed a corresponding solution algorithm. The model established the mechanical equilibrium equations for the wires by considering the bending moments, torques, shear forces, and axial forces. Moreover, the model accounted for the dynamic evolution of the helical wires’ lay angle and helix radius throughout the loading process. The reliability of the model was validated against experimental data and finite element (FE) simulation results. The effects of boundary conditions, initial lay angle, and the number of wire layers on the axial mechanical behavior of SPWCs were systematically investigated. The results indicated that the proposed model can accurately predict the elastic response of SPWCs under axial tension, with a mean absolute percentage error below 5% relative to FE and experimental results. Boundary conditions were identified as a dominant factor for the axial mechanical behavior of SPWCs. When torsionally restrained (AUTR), the SPWC’s mechanical behavior was equivalent to that of a solid steel rod, remaining insensitive to the initial lay angle and the number of wire layers. Conversely, under torsionally unrestrained conditions (AUTU), the significant tension-torsion coupling effect led to a nonlinear degradation in the axial stiffness of SPWCs. Compared with the AUTR condition, the SPWC exhibited a 29.2% reduction in its initial effective modulus under the AUTU condition. This degradation was further exacerbated by increased initial lay angle and the number of wire layers. As the initial lay angle was increased from 2° to 4°, the effective modulus of the SPWC was reduced by more than 16%. Expanding the total wire layers from 1 to 15 resulted in a 26.1% reduction in the initial effective modulus of the outermost layer.]]></description>
      <pubDate>Thu, 09 Jul 2026 13:29:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/2685133</guid>
    </item>
    <item>
      <title>Experimental Investigation of Ultrahigh-Performance Concrete for Capacity-Protected Pile Shafts Connecting with Precast Columns</title>
      <link>https://trid.trb.org/View/2617661</link>
      <description><![CDATA[The use of ultrahigh-performance concrete (UHPC) in pile shafts offers a promising solution for addressing challenges in the seismic design of connections between pile shafts and precast concrete columns. In particular, UHPC’s exceptional tensile properties enable the design of pile shafts that maintain capacity protection without requiring excessively large foundation or heavy reinforcement. This study experimentally examines the lateral load behavior of three 1/3-scale precast column-to-pile shaft assemblies, with variations in pile shaft material (normal concrete and UHPC), diameter, and transverse reinforcement spacing. The specimens were subjected to combined axial load and reversed cyclic lateral load. All specimens demonstrated similar lateral stiffness and strength and ultimately failed with maximum drift ratios reaching 8.53% due to flexure-induced damage at the column base. The normal concrete pile shaft showed moderate prying action–induced damage, whereas UHPC pile shafts, irrespective of diameter or reinforcement levels, remained uncracked throughout the tests. The use of UHPC allowed for a 13.3% reduction in pile shaft diameter and a 25% increase in transverse reinforcement spacing while maintaining capacity-protected performance, testifying to its efficiency for seismic connections in precast bridge pier systems.]]></description>
      <pubDate>Wed, 17 Jun 2026 16:14:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/2617661</guid>
    </item>
    <item>
      <title>Round-ended concrete-filled FRP tubes subjected to monotonic axial compression: Experimental study and design-oriented model</title>
      <link>https://trid.trb.org/View/2674436</link>
      <description><![CDATA[Round-ended cross sections, characterized by a rectangular middle segment with two semi-circular ends, are widely adopted in bridge piers due to their superior strong-axis bending resistance and aesthetic appeal. This study addresses a research gap in understanding the axial compressive behavior of round-ended concrete-filled FRP tubes (RE-CFFTs). While extensive research has been conducted on conventional CFFT sections (i.e., circular, square, rectangular, and elliptical sections), RE-CFFTs remain largely unexplored. Round-ended CFFTs can be considered a geometric intermediate between rectangular and elliptical sections, offering improved FRP confinement compared to rectangular CFFTs and superior constructability compared to elliptical CFFTs. A systematic experimental program involving 28 specimens was conducted to investigate the influence of cross-sectional aspect ratio ρ (i.e., the ratio of section length-to-semicircle diameter, ranging from 1.0 to 3.0 with an interval of 0.5) and FRP tube thickness on their axial compressive performance. It was found that all the RE-CFFT specimens failed by FRP hoop rupture located in or near the semicircular region of the cross-section, with the concrete core showing major diagonal cracks. The maximum hoop strain of RE-CFFTs was generally found at the semicircle midpoints or the connection portions of the semicircles and flat segments of the cross section. The aspect ratio ρ significantly affected the compressive stress-strain response and the hoop rupture strain of round-ended CFFTs. Within the ranges of the examined parameters, specimens with aspect ratio ρ ≤ 1.5 exhibited typical bilinear ascending curves, while those with ρ ≥ 2.0 displayed a descending second branch (i.e., softening behavior), potentially followed by rehardening. Both the peak stress and ultimate axial strain of confined concrete decreased progressively with increasing ρ. When the aspect ratio ρ ≥ 2.5, the strength enhancement ratio approached 1.0, suggesting empirically that a maximum aspect ratio ρ of 2.0 could serve as the threshold for strength enhancement in RE-CFFTs. Finally, a new design-oriented model was proposed to predict the axial stress-strain responses of RE-CFFTs, incorporating parameters considering the effective confinement area and the sectional aspect ratio. Validation against experimental data demonstrated the accurate prediction of the proposed model for key parameters including peak stress, ultimate strain, and overall curve profiles.]]></description>
      <pubDate>Wed, 17 Jun 2026 12:23:21 GMT</pubDate>
      <guid>https://trid.trb.org/View/2674436</guid>
    </item>
    <item>
      <title>Flexural performance of limestone calcined clay cement (LC³) concrete bridge piers under axial-lateral loading and chloride-induced corrosion</title>
      <link>https://trid.trb.org/View/2674489</link>
      <description><![CDATA[This paper presents the experimental results of limestone calcined clay cement (LC³) concrete bridge piers under axial-lateral loading and chloride wet-dry cycles. Accelerated corrosion test of sixteen specimens was performed under chloride exposure and wet-dry cycles combined with various axial loads, corrosion ratios, concrete types, concrete grades and reinforcement ratios. The flexural performance of three specimens with corrosion ratios of 0 %, 5 %, and 10 %, respectively, was evaluated through three-point bending tests. A theoretical model was proposed to predict the flexural properties of corroded bridge piers and validated by experimental data. Results revealed that increasing axial loads reduced corrosion ratio from 6.8 % to 2.8 % through mitigating cracks and chloride ingress. LC³ concrete piers exhibited localized corrosion and lower corrosion degree compared with ordinary Portland cement concrete piers. Flexural tests demonstrated that corrosion ratios of 5 % and 10 % reduced the ultimate flexural resistance by 11.5 % and 27.2 %, respectively, and decreased the ductility by 13.4 % and 22.8 %, respectively. Theoretical analysis demonstrated that there was a critical corrosion ratio of 10 %, after which higher corrosion ratios caused significantly higher adverse effect. Axial loading is beneficial for reducing the adverse corrosion effect especially for those with high corrosion ratios. The findings highlight the durability of LC³ concrete in corrosive environments and provide insights into resilient, low-carbon marine infrastructure.]]></description>
      <pubDate>Wed, 17 Jun 2026 12:23:21 GMT</pubDate>
      <guid>https://trid.trb.org/View/2674489</guid>
    </item>
    <item>
      <title>Scaling effect of large size RC columns under rockfall impact loading: Influence of gravity and axial load</title>
      <link>https://trid.trb.org/View/2680202</link>
      <description><![CDATA[To address the safety of large-size reinforced concrete (RC) columns in mountainous bridges subjected to rockfall impact, this study develops three-dimensional finite element (FE) models to investigate the scaling effect on the impact response of RC columns under the combined action of gravity and axial load. A series of numerical models with different scale factors (λ) and axial compression ratios (n) are established. Comparative analyses are conducted in terms of displacement, impact force, reaction force, and internal force evolution, thereby clarifying how the impact response evolves with scale factors under combined gravity-axial loading. The results show that including gravity significantly reduces the peak displacement of large-size RC columns (with a maximum reduction of approximately 12.8%) and weakens the displacement scaling effect. A pronounced coupling between axial load and scale factor is observed: at low axial compression ratios, axial pre-compression provides a beneficial preloading effect, whereas the large size combined with the high axial compression ratios tends to trigger P-δ instability, which amplifies the displacement scaling effect and reduces the system stability margin. Compared with the evident scaling effects on the secondary peak impact force and the reaction force, the peak impact force exhibits relatively low sensitivity to scale factor and axial load within the investigated parameter range. Mechanistic analyses indicate that the increased proportion of additional bending moments is a key contributor to the intensified displacement scaling effect in large-size columns. Moreover, the increase in impact kinetic energy with size is not synchronized with that in quasi-static energy absorption capacity, leading to more stringent dynamic demands for large-size columns. On this basis, predictive formulas for the scaling effects of peak displacement and impact force are established.]]></description>
      <pubDate>Wed, 17 Jun 2026 12:23:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/2680202</guid>
    </item>
    <item>
      <title>Research on axial friction forces induced by automobile double roller tripod joints</title>
      <link>https://trid.trb.org/View/2701168</link>
      <description><![CDATA[The double roller tripod joint (DRTJ) will generate two axial friction forces during the operation, namely the generated axial force (GAF) and the plunging resistant force (PRF). The GAF will cause “Shudder” of the vehicle, and the PRF will cause “Idle booming” of the vehicle. The NVH (Noise, Vibration and Harshness) problem caused by the two axial friction forces is particularly prominent in new energy vehicles. In order to study the influence of the operating conditions on the axial friction forces, a test bench for testing the axial friction forces of the DRTJ is established, and the testing methods for the GAF and the PRF of the DRTJ are proposed. The relationship between the axial friction forces and the joint bending angle, the transmitted torque, and the rotation speed is tested and analyzed. In order to predict the axial friction forces more effectively, a multi-body dynamics model of the DRTJ is proposed. The validity of the multi-body dynamics model is verified by the test, and the influence of the structure parameters of the DRTJ on the axial friction forces is subsequently analyzed using the multi-body dynamics model. Taking the structural parameters as design parameters, an effective method of optimizing the axial friction forces by optimizing the contact stress between the outer rollers and the raceways is proposed based on the finite element analysis method and the response surface method. The research results indicate that the axial friction forces can be reduced effectively using the proposed optimization method, which can provide an important reference for the design optimization of the DRTJ.]]></description>
      <pubDate>Wed, 20 May 2026 09:10:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/2701168</guid>
    </item>
    <item>
      <title>Load transfer mechanism and interaction evolution in pile-soil system to high-frequency axial load: Centrifuge modelling and numerical analysis</title>
      <link>https://trid.trb.org/View/2652810</link>
      <description><![CDATA[The dynamic interaction between pile and saturated soil governs pile settlement in soft soil foundation, which is strictly controlled in high-speed railways. However, the underlying mechanisms governing the transformation of dynamic load within the pile-soil system and their evolution over time remain inadequately understood. Therefore, conventional design methods that rely solely on static pile capacity and neglect dynamic interaction effects are inapplicable. In this study, a series of centrifuge modelling tests were conducted using a self-developed dynamic loading device and an instrumented model pile. The setup adequately satisfied the similitude requirements for intensified loading frequency and stress wave propagation along pile. Various static and dynamic loads were applied to the pile embedded in saturated silty soil, with frequencies reaching 360 Hz and cycles up to 5 × 105. Complementary numerical analyses were also performed to elucidate the mechanisms of dynamic pile-soil interaction. Experimental and numerical results demonstrate that stress waves propagated from the pile shaft into the surrounding soil in the form of Mach cone, driven by the differences in wave velocities between pile and soil. Moreover, soil vibration attenuated with increasing distance from the pile, a trend predictable using Bornitz’s approach even under loading frequencies as high as 360 Hz. The evolution of pore water pressure and the corresponding redistribution of axial force along the pile reveal distinct pile-soil interaction responses under different loading amplitudes: (1) Under low-amplitude loads (CLR ≤ 0.3), pore water pressure accumulation was negligible, shaft resistance carried most of the pile-head load without significant degradation, and base resistance remained minimal; (2) Under moderate loads (0.4 ≤ CLR ≤ 0.5), pore pressure accumulated noticeably, shaft resistance gradually degraded, axial force was transmitted to deeper pile segments, and base resistance increased but remained below its ultimate threshold; (3) Under high-amplitude loads (CLR ≥ 0.6), buildup of pore water pressure was most pronounced, shaft resistance degradation was substantial, base resistance increased significantly compared with moderate load levels, and deformation of the soil beneath the pile tip accumulated rapidly. Ultimately, these micromechanical processes led to distinct macro-scale settlement behaviours, i.e., stable, metastable, and unstable developments, which can be consistently explained by the evolving dynamic pile-soil interaction.]]></description>
      <pubDate>Tue, 21 Apr 2026 14:30:17 GMT</pubDate>
      <guid>https://trid.trb.org/View/2652810</guid>
    </item>
    <item>
      <title>Instability of the middle partition in deep shafts of tunnels in water-rich strata: A case study of Tianshan Shengli Tunnel No.1-1 shaft</title>
      <link>https://trid.trb.org/View/2689876</link>
      <description><![CDATA[The middle partition is crucial structure in the ventilation shaft of a transportation tunnel, and it is also a weak point in the overall stability of a deep tunnel shaft. However, there is a lack of research reports on the instability of middle partition in deep shafts in water-rich strata. Based on the No. 1-1 shaft of the Tianshan Shengli Tunnel, currently the world’s longest operational expressway tunnel. Theoretical analysis and on-site measurement methods were adopted to conduct research on the instability and failure of middle partition in shafts. The results of both methods with numerical calculations were compared. It was indicated that the main cause of the instability of the middle partition is unbalanced water level on both sides. The larger the tunnel shaft diameter, the more unfavourable the bearing stability of the middle partition. The midspan displacements and bending moments of the middle partition increase with increasing water level difference load, and the values increase with higher axial loads. Furthermore, the midspan displacements and bending moments of the middle partition decrease with the increase of section parameters and increase with the increase of tunnel shaft diameter. However, they are not significantly affected by the change of concrete strength grade and reinforcement diameter. The water level difference between the one side of the middle partition led to a three-phase trend of “rapid growth, slow growth, decline” in middle partition displacement, and they all had the characteristics of the closer to the water level. The theoretical solution is better matched with the results of on-site measurements and numerical calculations, which can reflect the instability and failure of the middle partition. On-site measurements also confirmed the cause of the instability and failure of the middle partition. The axial load threshold for instability and failure is 0.03 MPa, and the water level difference load threshold is 10 kN/m. Research results can provide a reference for the design and construction of middle partition in tunnel shaft in water-rich stratas.]]></description>
      <pubDate>Mon, 13 Apr 2026 09:37:44 GMT</pubDate>
      <guid>https://trid.trb.org/View/2689876</guid>
    </item>
    <item>
      <title>A theoretical approach for axial compressive analysis of helical piles supporting offshore jacket structures</title>
      <link>https://trid.trb.org/View/2673905</link>
      <description><![CDATA[Helical piles are extensively employed to support offshore jacket structures and withstand lateral loads through a push-pull mechanism. Nevertheless, there is still a dearth of research on their compressive capacity associated with settlement, especially for multi-helix piles. This limitation impedes the advancement of response-based design methodologies. To address this gap, this study presents a comprehensive unified theoretical framework for analyzing the axial compressive response of multi-helix piles associated with both individual bearing mode and cylindrical shear mode. The analysis framework is based on two key components: (1) a multi-fictitious soil pile model that model effectively integrating the two distinct bearing mechanisms, and (2) a semi-analytical solution for helical pile response derived using the transfer matrix method. Validation against several reported cases demonstrates that the proposed method provides a reliable tool for predicting the axial compressive behavior of helical piles across diverse scenarios, ensuring its applicability to practical engineering design. Furthermore, parametric studies offer valuable insights into the factors influencing pile response and provide practical guidelines for optimizing helix spacing design. This study contributes to advancing the understanding of helical pile behavior and supports the development of more efficient and reliable design methodologies for offshore helical piles.]]></description>
      <pubDate>Wed, 25 Mar 2026 11:44:51 GMT</pubDate>
      <guid>https://trid.trb.org/View/2673905</guid>
    </item>
    <item>
      <title>Energy-based criteria for assessment of box girder highway bridges subjected to pier loss against progressive collapse</title>
      <link>https://trid.trb.org/View/2648194</link>
      <description><![CDATA[This study introduces energy-based failure criteria for reinforced concrete bridge piers aimed at evaluating the progressive collapse potential of box girder highway bridges. A real-world bridge located in Tehran, is employed as a representative case study. To broaden the applicability of the findings, variations in the bridge’s geometric and structural parameters are incorporated to reflect a range of typical highway bridge configurations. Two principal energy-based criteria are established: the limit state energy, corresponding to the pier’s ultimate load-bearing capacity, and the failure energy, which serves as a sufficient criterion for assessing progressive collapse susceptibility. A total of 15 finite element models were developed for the investigation; 13 of which were single-pier models representing monolithic joint, span-by-span, and balanced cantilever systems with varying span lengths, used to establish the energy-based criteria. The remaining two models were three-span bridge systems utilized to validate the criteria and examine the progressive collapse potential of the full bridge configurations under instantaneous pier removal scenarios. The results demonstrate that piers in monolithic systems exhibit superior energy dissipation compared to those in span-by-span systems, which in turn outperform balanced cantilever systems. Additionally, shorter spans consistently showed better energy dissipation than longer spans. However, in the full bridge models subjected to pier removal scenarios, monolithic bridge configurations show greater susceptibility to progressive collapse, while span-by-span systems display a higher capacity to prevent collapse propagation. In these models, the failure criteria were only exceeded by the collapsed piers, highlighting the reliability and predictive accuracy of the criterion.]]></description>
      <pubDate>Tue, 24 Mar 2026 09:09:08 GMT</pubDate>
      <guid>https://trid.trb.org/View/2648194</guid>
    </item>
    <item>
      <title>Analytical method considering P-Δ effect and soil densification effect of vertical load for the effect of asymmetric scour on pile lateral capacity in sand under combined loads</title>
      <link>https://trid.trb.org/View/2644044</link>
      <description><![CDATA[Scour reduces the lateral bearing capacity of pile foundations. However, scour is asymmetrical in reality, and ignoring this fact may lead to discrepancies between the pile foundation bearing capacity obtained and the actual bearing capacity. Under combined loads conditions, vertical loads not only produce P-Δ effect, but also alter the stiffness of the soil around the piles, resulting in soil densification and affecting the lateral bearing capacity of the piles. This paper modifies the ultimate soil resistance based on the asymmetric scour model and introduces a couple loading factor KVH to account for the soil densification effect caused by vertical load, thereby obtaining a modified p-y curve. Based on stress analysis, the differential equation of pile deflection is constructed, and a method is proposed to analyze the effect of asymmetric scour and combined loads coupling on the lateral bearing capacity of pile. The accuracy of the proposed analytical method is verified through existing research cases. Finally, this paper analyzes the influence of asymmetric scour on lateral bearing capacity, as well as the effects of asymmetric scour and combined loads on the P-Δ effect and soil consolidation effect. The results indicate that, compared with other scour parameters, passive scour depth has the greatest impact on the lateral bearing capacity of pile foundations. Asymmetric scour affects the P-Δ effect by influencing the lateral displacement of piles, while its impact on soil densification effect is achieved by influencing the ultimate soil resistance.]]></description>
      <pubDate>Fri, 13 Mar 2026 08:46:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/2644044</guid>
    </item>
    <item>
      <title>An experimental investigation on the ultimate strength of leg mating units under axial load</title>
      <link>https://trid.trb.org/View/2637895</link>
      <description><![CDATA[Leg Mating Units (LMUs) are critical components in offshore platform installations, which serves to absorb impact energy and ensure stable load transfer during the mating process between topside modules and substructures. However, their structural performance under extreme axial loads remains a key concern for engineering reliability. This study investigates the ultimate strength and failure mechanisms of LMUs in offshore platforms under axial loading, aiming to address the challenges of high costs and implementation difficulties associated with full-scale testing. By combining nonlinear finite element simulations in ABAQUS with 1:5 scaled physical experiments, the research systematically analyzes the ultimate bearing capacity, deformation patterns, and stress distribution of LMU rubber stacks. The results indicate that the rubber stack undergoes significant compression under the maximum enforced displacement, and the compression volume of the lower rubber layer increases significantly compared with the upper layer. The stress peak of the steel structure is much lower than the yield strength of the material, which verifies the reliability of the structure design. The scaling test method established in this study provides an economical and effective technical method for evaluating the structural performance of large LMUs.]]></description>
      <pubDate>Tue, 10 Mar 2026 09:55:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2637895</guid>
    </item>
    <item>
      <title>Performance Testing of GRS Test Piers Constructed with Florida Aggregates – Axial Load Deformation Relationships</title>
      <link>https://trid.trb.org/View/2663599</link>
      <description><![CDATA[A series of full-scale axial load-deformation tests on instrumented GRS piers were conducted using materials approved for use in Florida. The piers were designed and constructed following the FHWA and FDOT guidelines for dimensional ratio of height/width = 2, compacted backfill of poorly graded No. 57, well graded RCA-GAB, and a LWA (as a trial experiment), reinforced with biaxial and uniaxial woven polypropylene geosynthetics with a minimum of 4,800 lbs/ft strength spaced 8 inches apart, and confined with 86 lbs segmental facing blocks. The primary objectives were to investigate the behavior of GRS composites specific to Florida design practice, provide accurate stress-strain data for design purposes and evaluate the GRS composite structure axial and horizontal strains under service pressure. Large diameter triaxial tests were performed are appropriate for testing well graded materials. The analysis of triaxial results showed the influence of triaxial specimen on shear strength properties of well-graded RCA-GAB. Conducting triaxial tests on 6-inch diameter specimens led to an increase in the friction angle by 11.4° and 8.5° for peak and residual states, respectively, compared to 4-inch specimens. All GRS piers tested met the FHWA service limit criteria for GRS-IBS satisfactorily. At applied vertical g pressure of 4 ksf (FHWA recommended dead plus live load, with load factors =1), the vertical strain for all GRS piers was below 1%, with lateral strain below 0.51%. The applied vertical pressure needed to achieve 1% vertical strain ranged from 4.1 ksf to 19 ksf for all piers, while the pressure required to reach 2% lateral strain varied from 11 ksf to 32 ksf. Comparison of experimental data with FHWA design methods for GRS-IBS showed that the FHWA ultimate capacity equation consistently underestimated the measured vertical capacity of piers constructed with open graded-No 57 and well graded RCA-GAB backfills when the residual friction angle from large diameter triaxial tests are used. The FHWA equation for lateral displacement accurately predicted the lateral displacement of the facing walls during loading. The assumption of zero volume change was found to hold only below the applied vertical pressure of 4 ksf. The results of the load-deformation tests provide 7 additional values to the dataset of FHWA bearing capacity bias with which new resistance factors were calculated following the AASHTO strength I load combination and using the First Order Second Moment (FOSM) method. For deal to dead + live load ratio of 0.37, resistance factors were calculated to be 0.57, 0.53, 0.44, and 0.37 for reliability indices of 2.33, 2.5, 3.0, ad 3.5, respectively.]]></description>
      <pubDate>Fri, 20 Feb 2026 08:49:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/2663599</guid>
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