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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>Fatigue damage model for precast bridge piers reinforced with high-strength rebar</title>
      <link>https://trid.trb.org/View/2772345</link>
      <description><![CDATA[Although extensive research has been conducted on the seismic performance of precast piers, there is limited focus on fatigue damage due to long-duration earthquakes. To address this gap, this article tests the fatigue performance of precast bridge piers fortified with high-strength rebar. The results reveal that the fatigue strength of the pier did not witness substantial degradation until the loading drift reached the yield drift. Beyond the yield drift, a more significant fatigue loading drift led to more extensive damage during the first loop and a shorter fatigue lifespan. Notably, the fatigue lifespan dropped sharply when cyclic displacement amplitude exceeded twice the yield displacement. Based on experimental data, a fatigue strength degradation model is proposed, using the first loop’s peak lateral strength as the coefficient and the cycle count as the base. In addition, the establishment of the cumulative fatigue damage model provides a means to gauge the damage in bridge piers. The findings provide valuable insights for the design and assessment of precast bridge piers under long-duration earthquakes, enhancing the understanding of seismic behaviour and fatigue damage in piers strengthened with high-strength rebar.]]></description>
      <pubDate>Thu, 08 Oct 2026 17:03:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/2772345</guid>
    </item>
    <item>
      <title>Dynamic monitoring of sleeper strain and ballasted support condition based on embedded fiber-reinforced polymer–optical fiber sensing rebar</title>
      <link>https://trid.trb.org/View/2705623</link>
      <description><![CDATA[Ballasted track structures face fatigue, cracking, and settlement risks over time, making long-term health monitoring essential, but traditional patch-type sensors are unsuitable due to exposure issues. To overcome this limitation, this research proposes an embedded fiber-reinforced polymer optical-fiber (FRP-OF) composite strain sensor based on Fiber Bragg Grating (FBG). The FRP-OF sensing rebar was customized to sleeper dimensions, embedding optical fibers with inscribed positioning gratings within a composite matrix of glass fibers and resin. By embedding the sensor inside the concrete sleeper and real-time, stable monitoring of strain responses under dynamic load was achieved. Compared with traditional patch-type strain sensor, the embedded FRP-OF sensing rebar exhibits superior recognition capability and stability. Field test results further showed that the sensing rebar could not only clearly identify the tamping operations during the maintenance process, but also effectively reflect and infer the variations in ballast support stiffness. Simulation analysis indicated that the sleeper embedded with the sensor effectively captured the influence of train load, speed variation, and ballast support conditions on the monitoring results. In particular, under hanging defect condition, the simulation successfully showed the phenomenon of strain concentration and the enhanced response at the defect location, validating the reliability of the FRP-OF sensing rebar in detecting abnormal ballast support conditions.]]></description>
      <pubDate>Tue, 08 Sep 2026 11:41:44 GMT</pubDate>
      <guid>https://trid.trb.org/View/2705623</guid>
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    <item>
      <title>CREATE Year1 Dataset for Combining Structural and Cathodic Protection with Titanium Alloy Bars [supporting dataset]</title>
      <link>https://trid.trb.org/View/2742394</link>
      <description><![CDATA[This data archive is for the Year 1 CREATE Project with support from BIL UTC under Grant No. 69A3552348330. The archive centralizes salient experimental measurements, metadata, and outputs generated by the research team. It includes: (1) Electrochemical data:  high-resolution images of specimens and test conditions, polarization, bulk resistivity, and open-circuit half-cell potential measurements from multiple specimen types. (2) Structural data: high-resolution images of specimens, material test results, pullout specimen force-deformation responses, beam specimen strain measurements and load-deformation responses. (3) Supporting documentation: detailed scaled drawings of specimens and instrument configurations, data dictionaries, and README files for reproducibility. Data are organized in a standardized directory structure with descriptive naming conventions, and file formats suitable for long-term accessibility, reuse, and future modeling efforts. All datasets are backed up securely and accompanied by descriptive metadata to ensure transparency, traceability, and compliance with CREATE archive standards.]]></description>
      <pubDate>Mon, 24 Aug 2026 08:44:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/2742394</guid>
    </item>
    <item>
      <title>Preventing Corrosion of Steel in Road Infrastructure</title>
      <link>https://trid.trb.org/View/2727681</link>
      <description><![CDATA[Steel is a versatile construction material having very high strength to weight ratio and recyclability and widely used in infrastructure projects including highway projects. Not with standing versatility of steel use, durability of steel structures and reinforced/prestressed concrete structures is a big challenge due to the single reason of corrosion of steel. The overall impact of corrosion of steel is reduction of useful life of structures, increased cost of repair/ rehabilitation/retrofitting apart from various indirect losses like disruption to traffic. Undertaking repair/rehabilitation/ retrofitting is, at times, more challenging than original construction spanning from conceptualization to design and actual execution. Corrosion of steel can be minimized/delayed though not prevented in a variety of ways. Applicability of particular treatment depends upon several factors. For a given situation, more than one method may also be used. The process also covers all phases of project cycle starting from planning to design, detailing, construction and asset management. Due diligence should be exercised to select the appropriate treatment considering site vulnerability, strategic importance of the structure, anticipated life & sensitivity of the product and life cycle costing. Asset management is a key requirement in every case. For example, periodic cleaning and painting of structural steel elements helps extending useful life of the bridge/structure. Same principle applies to reinforced/ prestressed concrete elements too. Considering the enormity of the situation, all the stakeholders must rise to the occasion to minimize corrosion of steel in bridges and structures.]]></description>
      <pubDate>Tue, 21 Jul 2026 09:49:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/2727681</guid>
    </item>
    <item>
      <title>Thermoplastic Composite Rebar Durability and Mechanical Testing</title>
      <link>https://trid.trb.org/View/2724672</link>
      <description><![CDATA[This research investigated the viability of novel glass-fiber reinforced thermoplastic (TP) composite rebars, manufactured using a continuous forming process, as a potential field-bendable and corrosion-proof alternative to conventional steel and commercial glass-fiber reinforced thermoset (TS) rebars. The study focused on TP composites using polybutylene terephthalate (PBT), polyamide-12 (PA12), and polypropylene (PP), evaluating their physical, mechanical, and thermal properties based on industry standards (ACI, AASHTO, ASTM). TP bars were manufactured using a continuous forming process. Baseline characterization identified GF+PBT composites as the most promising, performing comparably to TS rebars, though results indicated a need for improved matrix consolidation. Durability was assessed via immersion in high-pH alkaline solutions (pH 12.6-13.0) at elevated temperatures (up to 80°C). Unlike TS rebars which showed minimal degradation, the GF+PBT bars exhibited significant strength loss and matrix degradation, linked to high moisture uptake. This highlights a critical need for improved matrix chemical resistance and lower void content. Overall, GF+PBT rebars show significant promise but require further optimization in processing and matrix formulation to improve chemical resistance.]]></description>
      <pubDate>Tue, 14 Jul 2026 13:34:59 GMT</pubDate>
      <guid>https://trid.trb.org/View/2724672</guid>
    </item>
    <item>
      <title>Anchorage performance of large-diameter high-strength steel bar grouted corrugated duct connections: Experimental study, numerical simulation, and reliability analysis</title>
      <link>https://trid.trb.org/View/2684534</link>
      <description><![CDATA[The grouted corrugated duct connection (GCDC) is a widely adopted technique for connecting column-cap beam and column-foundation joints in prefabricated bridge construction. The incorporation of large-diameter high-strength steel bars (LD-HSSB) in GCDC systems can significantly reduce the number of required connections, thereby enhancing construction efficiency. To investigate the anchorage performance of LD-HSSB (nominal diameter 32 mm, yield strength 600 MPa) embedded in GCDC, a series of pull-out tests were conducted. The tests focused on two key parameters: the bar anchorage length (la) and the duct-to-bar diameter ratio (D/d), where D denotes the inner diameter of the GCDC and d represents the bar diameter. The results indicate that anchorage length is the predominant factor governing both the failure mode and bond behavior. The ultimate anchorage force (Fu) increases with la up to approximately 15d, beyond which it tends to stabilize, whereas la exerts only a minor influence on the initial bond stiffness. Among the three tested D/d ratios (2.34, 3.00, and 3.56), the optimal anchorage performance was observed at D/d = 3.00. A rib-scale refined finite element model (FEM) was developed and validated against the experimental results. Extended parametric analyses were subsequently performed, encompassing both the tested parameters and grout strength, to gain a more comprehensive understanding of the anchorage mechanism in GCDC. Based on the experimental and numerical findings, an empirical equation for predicting the average bond strength was proposed, and the rational design anchorage length was determined through reliability-based analysis.]]></description>
      <pubDate>Tue, 30 Jun 2026 10:21:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/2684534</guid>
    </item>
    <item>
      <title>Steel reinforced CA-UHPC one-way slabs: Experimental study, numerical simulation, and bridge deck application</title>
      <link>https://trid.trb.org/View/2677743</link>
      <description><![CDATA[Incorporating coarse aggregate (CA) into ultra-high performance concrete (UHPC) to produce CA-UHPC provides a cost-effective material alternative for bridge deck construction. This study investigates the structural behavior of CA-UHPC one-way slabs, motivated by the reinforcement design requirements of a real bridge deck. A series of flexural tests were conducted to examine the influence of reinforcement schemes on structural performance. As the tensile reinforcement ratio increased from 0.42 % to 8.06 %, the slab failure mode transitioned from under-reinforced to balanced-reinforced and finally to over-reinforced. The flexural capacity and ductility of the balanced-reinforced slab improved steadily owing to the synergistic work of steel fibers and rebars in the tensile region, whereas the ductility of the over-reinforced slab decreased due to premature concrete crushing before steel yielding. A refined finite element (FE) model was developed for numerical validation, incorporating a concrete damage plasticity (CDP) formulation for CA-UHPC and a user-defined cohesive element to simulate the bond stress-slip relationship at the rebar-concrete interface. Specifically, a tensile cracking law was employed in the CDP model to describe the post-cracking softening behavior of the CA-UHPC material. The model accurately reproduced the ductile flexural response observed in the tests. Parametric analysis further evaluated the effects of rebar diameter, CA-UHPC tensile strength, and fracture energy. Based on the experimental study, an optimal reinforcement ratio was recommended and subsequently adopted in the real bridge deck design.]]></description>
      <pubDate>Wed, 17 Jun 2026 12:23:21 GMT</pubDate>
      <guid>https://trid.trb.org/View/2677743</guid>
    </item>
    <item>
      <title>Development of Pipe Pile to Bent Cap Connection for ALDOT Bridges</title>
      <link>https://trid.trb.org/View/2698486</link>
      <description><![CDATA[Steel pipe piles are a promising alternative to traditional H-piles and drilled shafts for ALDOT bridge substructures because they can achieve high force and moment capacity and enable more efficient construction. However, current guidance on steel pipe pile–to–reinforced concrete bent cap connections is limited, and practices among state DOTs vary widely in embedment length, connection detailing, and assumed fixity. This project was undertaken to develop and evaluate practical, code-compliant connection details that can support consistent design assumptions and potential standardization. An extensive survey of state DOTs regarding their steel pipe pile use and pipe pile–to–bent cap connection detailing practices was first conducted. Based on the survey results, an experimental program was designed to quantify the lateral-load behavior of large-diameter steel pipe pile–to– bent cap connections representative of common DOT practices. Five full-scale connection configurations were tested under repeated lateral loading with three rebar-based systems (headed, hooked, and straight bars) utilizing shallow embedment of 1 ft, and two mechanical anchorage systems (headed stud and annular ring) utilizing deeper embedments of 2–3 ft. For the rebar-based configurations, concrete plug depth was governed by reinforcement development/anchorage demands, while the mechanical anchorage configurations were evaluated with reduced plug depths. All configurations sustained the maximum applied loads without failure; all tests were terminated due to equipment limits rather than specimen capacity. The mechanical anchorage systems exhibited higher stiffness than the shallow rebar systems by about 2 times. The rebar-based systems exceeded their calculated nominal flexural strengths by at least 1.8 times. Embedment lengths on the order of one-third of the pile diameter provided a reasonable moment transfer, indicating that idealized “pinned” assumptions may not be applicable for hollow pipe piles. This report provides comparative experimental data and an implementation appendix (Appendix C) that supports selection and detailing of steel pipe pile–to–bent cap connections for ALDOT bridges. The findings further establish a foundation for future research to refine and optimize the design methodology of favorable connection configurations and further extend the methodology to pile-cap connections.]]></description>
      <pubDate>Tue, 12 May 2026 09:47:05 GMT</pubDate>
      <guid>https://trid.trb.org/View/2698486</guid>
    </item>
    <item>
      <title>Experimental Investigation of Development Length Required for Large Diameter Headed Reinforcing Bars in Tension</title>
      <link>https://trid.trb.org/View/2696134</link>
      <description><![CDATA[The study presented in this report was to investigate the anchorage capacities of No. 14 and No. 18 headed bars, including the influence of the embedment length, concrete strength, head size, parallel tie reinforcement, and bar group on the anchorage strength, and evaluate the applicability of the development length requirements for No. 11 or smaller headed bars in ACI 318-19 and the 10th Edition of AASHTO LRFD Bridge Design Specifications to larger diameter bars. Thirteen bar anchorage tests were conducted. Eleven of these had single bars and two had double side-by-side bars. Heads with net bearing areas of 4Ab and 9Ab, were considered. The target compressive strengths of the concrete used were 4,000, 6,000, and 8,000 psi. The specimens had bar embedment lengths equal to 70% or 100% of the minimum according to ACI 318-19. The test results show that the anchorage failure of a headed bar is normally initiated by concrete breakout but eventually governed by bar pullout when the bearing strength of the concrete at the T head has been weakened by the opening of breakout cracks. The bar force at which concrete breakout occurs is approximately proportional to the square of the embedment length, rather than the embedment length to the power of 1.5 as specified in ACI 318 for embedded anchor bolts. After the occurrence of breakout cracks, parallel tie reinforcement can play a significant role in providing the necessary anchorage capacity. The specimens that satisfied the development length formula in ACI 318-19 performed satisfactorily. Two specimens that satisfied the AASHTO formula and had a head size of 9Ab had anchorage failures. This indicates that the AASHTO formula over-estimates the influence of the head size. The unified formula in AASHTO considers only the bond strength and the bearing resistance at the T head, and does not explicitly account for concrete breakout. It can be perceived that if anchorage failure is initiated by concrete breakout, the size of the T head will not have a significant influence on the anchorage resistance, as supported by the data in this study and other prior studies on smaller diameter bars, which have shown that the use of a head size greater than 4Ab will not necessarily improve the anchorage capacity and the benefit is small at best. Even though the ACI formula appears to be safe for the large-diameter bars, it is more conservative for No. 18 bars than No. 14 bars, probably due to the fact that the development length is proportional to the bar diameter to the power of 1.5. A rational method has been proposed in this study to determine the development lengths for headed bars and the required parallel tie reinforcement. It is based on the anchor bolt provisions in ACI 318, which have been improved to account for the influence of the bar embedment length and the contribution of the parallel tie reinforcement in an accurate and rational manner.]]></description>
      <pubDate>Mon, 04 May 2026 11:19:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/2696134</guid>
    </item>
    <item>
      <title>Corrosion Resistance of Using Very High Strength Steel Reinforcing Bars in Reinforced Concrete Beams– An Experimental and Analytical Approach</title>
      <link>https://trid.trb.org/View/2694443</link>
      <description><![CDATA[Project Description: Advancements in manufacturing methods and the growing demand for high-strength materials in reinforced concrete have led to the development of steel reinforcing bars with strengths exceeding 100 ksi. These ultra-high-strength bars hold significant promise for bridge construction, as they could extend feasible span lengths beyond those achievable with conventional reinforcement while still meeting strength and serviceability requirements. Their use can also reduce girder depth, leading to material savings and lower overall construction costs. However, successful implementation requires addressing key concerns regarding serviceability and durability. Critical factors include corrosion resistance, structural behavior, and ductility of beams reinforced with these high-strength bars. 
The primary objective of the proposed work is to investigate the durability (corrosion resistance) and serviceability of concrete girders reinforced with very high-strength reinforcement, by testing bond-slip relationship between corroded and non-corroded steel rebars and concrete. 12 medium-span (8 in x 12 in x 10 ft) concrete beams will be cast and tested for strength and ductility. Six of the 12 beams will be subjected to accelerated corrosion. Under controlled conditions, the research team will test the strength and ductility characteristics of the beams reinforced with these bars. 
By addressing the performance of very high-strength reinforcing bars in reinforced concrete girders and their behavior under corrosive conditions, this project advances the application of durable, next-generation materials for transportation infrastructure.
]]></description>
      <pubDate>Thu, 23 Apr 2026 18:10:34 GMT</pubDate>
      <guid>https://trid.trb.org/View/2694443</guid>
    </item>
    <item>
      <title>Feasibility of Engineered Cementitious Composites (ECC) as Joint Material for Accelerated Bridge Construction (ABC)</title>
      <link>https://trid.trb.org/View/2694442</link>
      <description><![CDATA[Advancements in manufacturing methods and the growing demand for high-strength materials in reinforced concrete have led to the development of steel reinforcing bars with strengths exceeding 100 ksi. These ultra-high-strength bars hold significant promise for bridge construction, as they could extend feasible span lengths beyond those achievable with conventional reinforcement while still meeting strength and serviceability requirements. Their use can also reduce girder depth, leading to material savings and lower overall construction costs. However, successful implementation requires addressing key concerns regarding serviceability and durability. Critical factors include corrosion resistance, structural behavior, and ductility of beams reinforced with these high-strength bars. 
The primary objective of the proposed work is to investigate the durability (corrosion resistance) and serviceability of concrete girders reinforced with very high-strength reinforcement, by testing bond-slip relationship between corroded and non-corroded steel rebars and concrete. 12 medium-span (8 in x 12 in x 10 ft) concrete beams will be cast and tested for strength and ductility. Six of the 12 beams will be subjected to accelerated corrosion. Under controlled conditions, the research team will test the strength and ductility characteristics of the beams reinforced with these bars. 
This study directly supports the mission of the Center for Healthy and Durable Transportation (CHDT), a University Transportation Center (UTC), whose primary research focus is enhancing the durability and service life of transportation infrastructure through innovative construction materials and techniques. By addressing the performance of very high-strength reinforcing bars in reinforced concrete girders and their behavior under corrosive conditions, this project advances the application of durable, next-generation materials for transportation infrastructure.

]]></description>
      <pubDate>Tue, 21 Apr 2026 13:16:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/2694442</guid>
    </item>
    <item>
      <title>Performance of Epoxy-Coated Steel in Continuously Reinforced Concrete Pavement</title>
      <link>https://trid.trb.org/View/2680618</link>
      <description><![CDATA[Sections of Interstate 35 in Noble and Logan Counties of Oklahoma were recently reconstructed. The reconstruction involved replacing the existing pavement with continuously reinforced concrete pavement. On both projects, northbound lanes were reinforced with epoxy-coated steel and southbound lanes were reinforced with uncoated steel. This side-by-side construction provides an excellent opportunity for comparing the performance of pavement constructed with epoxy-coated reinforcement to pavement constructed with uncoated reinforcement. The investigation described herein included a complete crack survey on both projects, installation of half-cell sites and gauge points, construction of laboratory specimens, and comparison of measured crack spacings and widths to calculated values. Results of the crack survey indicate that average crack spacing is stabilizing between 4 and 6 ft. Average crack spacing on pavements constructed with coated steel is less than on pavements constructed with uncoated steel, but the difference is small. Initial half-cell readings indicate little or no corrosion activity on either the coated or uncoated steel. Comparison of laboratory specimens constructed with coated and uncoated steel reveals no significant difference in terms of stiffness, force required to cause cracking, or average crack width. On the basis of the results of this investigation, it is concluded that performance early in the life of a continuously reinforced concrete pavement is not significantly affected by the use of epoxy-coated reinforcing steel. However, if the reinforcement begins to corrode, the coated steel should have a significant advantage. It is recommended that crack surveys and half-cell measurements be performed on a regular basis to assess long-term effects.]]></description>
      <pubDate>Sat, 04 Apr 2026 17:15:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/2680618</guid>
    </item>
    <item>
      <title>Evaluation of Potential Uses for a Hand Held Portable X-ray Fluorescence Spectrometer</title>
      <link>https://trid.trb.org/View/2636021</link>
      <description><![CDATA[One of the renewal projects under the Second Strategic Highway Research Program (SHRP 2) explored the potential for broad use of portable spectroscopic devices to fingerprint construction materials commonly used in transportation infrastructure. One of the instruments identified as having potential was a portable X-ray Fluorescence (XRF) instrument. In addition to the uses identified by the research project, there are some potential Iowa specific applications that are explored in this report. Testing was done on carbonate aggregates and stainless-steel reinforcement. The conclusions are: 1. The handheld XRF was quick and easy to operate compared to the laboratory XRF. A technician with a few hours of training could perform tests on a wide variety of materials such as soils, rock, paint, plastics, and metals. 2. The handheld XRF with the metals library does very well at identifying the metal type. The flexibility to add additional element limits and metal types to the library is a useful feature for use on specialty alloys. 3. Once the handheld XRF was calibrated for carbonate aggregates, it was fairly accurate and repeatable on prepared samples of rock and powder. Curved or rough surfaces appeared to reduce the accuracy and repeatability. 4. The XRF fingerprint matching algorithm was unable to consistently match pebbles from the same sample. An enhanced algorithm using the full spectrum might produce better results. Some sample preparation might also improve the accuracy.]]></description>
      <pubDate>Mon, 02 Mar 2026 16:12:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/2636021</guid>
    </item>
    <item>
      <title>Development of Design Recommendations for Noncontact Hooked Bar Lap Splices for Large Reinforcing Bars</title>
      <link>https://trid.trb.org/View/2671993</link>
      <description><![CDATA[On wide bridges, precast concrete pier caps are often constructed in multiple segments and connected on site because of transportation or construction limitations. When these segments are connected through closure joints, contractors use lap splices of straight reinforcing bars. However, the splice lengths of large (e.g., No. 11) straight bars must be very long to develop the yield strength of the bars. The cost of long splices may offset the benefit of using precast concrete. To reduce splice lengths, bridge designers use hooked bars in noncontact lap splices, presuming that hooked bars allow for shorter splice lengths. The use of noncontact splices avoids conflicts during fit-up in the field. However, neither substantial design guidance nor studies of the behavior of hooked bar lap splices in large concrete elements exists to justify this design philosophy. To develop design guidance for noncontact hooked bar lap splices, 73 large-scale beam-splice specimens were tested to simulate the closure connection between precast pieces. The bond and anchorage parameters of the noncontact hooked bar lap splices varied, including parameters such as the splice spacing, concrete compressive strength, cover depth, casting position, number of spliced reinforcement layers, hook shape, splice length, number of bundled bars, number of lap splices, amount of transverse reinforcement, and dosage of steel fibers. In addition, nonlinear finite element analyses were conducted to investigate the force transfer mechanism in noncontact hooked lap bar splices and predict splice strength over a wider range of splice configurations than tested in the laboratory. Results indicated that noncontact hooked bar lap splices without transverse reinforcement (e.g., ties) can fail because the eccentricity between lapped bars causes “hook side bulging,” a tension failure concentrated at the hooked ends closest to the sides of a beam. In contrast, splices with transverse reinforcement experienced failure modes such as side-face blowout and concrete crushing. Noncontact hooked bar lap splices had weaker splice strengths than contact splices. Nevertheless, hooked bars are an effective means of reducing required splice lengths. On average, the use of steel fibers and increases in lap length, concrete compressive strength, cover, amount of transverse reinforcement, or the number of lap splices allowed for greater stress to be developed in spliced bars. All else being equal, an increase in either bar size or the number of spliced reinforcement layers decreased the stress that could be developed in the spliced bars. A design equation was developed for the minimum required lap length of hooked bars, which uniformly characterizes the influence of the variables over the ranges explored in this study. To enable immediate implementation of the design equation in practice, design examples and proposed code language were also prepared for incorporation into relevant standards.]]></description>
      <pubDate>Sat, 28 Feb 2026 17:17:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/2671993</guid>
    </item>
    <item>
      <title>Mechanical degradation of naturally corroded rebars from a 45-year-old bridge slab: 3D quantification of section loss and a new corrosion damage indicator</title>
      <link>https://trid.trb.org/View/2670428</link>
      <description><![CDATA[Corrosion of reinforcing steel is a principal cause of degradation and strength loss in reinforced concrete (RC) structures, particularly those exposed to aggressive environmental conditions over extended service periods. This study investigates the residual mechanical performance of fifty-seven naturally corroded rebars extracted from a 45-year-old bridge deck. Based on chloride exposure records and damage inspection, corrosion initiation was estimated to have occurred approximately 24 years after construction. A simplified three-dimensional reconstruction method was developed to capture local cross-sectional loss and pit depth at the fracture zone. The resulting geometric indicators were then correlated with the tensile properties—yield strength, ultimate strength, and elongation—to assess the mechanical degradation due to corrosion. Among the tested parameters, a combined index incorporating maximum pit depth and residual cross-sectional area exhibited the strongest and most consistent correlation with mechanical strength, effectively reducing the data scatter typical of single-parameter models. The proposed empirical relationships provide a practical approach for estimating the residual tensile capacity of corroded reinforcement, thereby supporting quantitative durability assessment and service-life prediction of long-term RC bridge structures.]]></description>
      <pubDate>Mon, 23 Feb 2026 11:24:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/2670428</guid>
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