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    <title>Transport Research International Documentation (TRID)</title>
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    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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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>Reclamation and Recycling Techniques to achieve Perpetual Pavements Characteristics</title>
      <link>https://trid.trb.org/View/2703795</link>
      <description><![CDATA[This study evaluates Cold In-place Recycling (CIR) for developing sustainable and cost-effective perpetual pavements. As part of the 2022 National Road Research Alliance (NRRA) construction, four test sections were constructed at the MnROAD mainline section to utilize CIR and additionally assess the effects of incorporating rejuvenator in cold recycled asphalt materials. Two sections included bituminous layer over aggregate base, while the other two included bituminous overlay over stabilized full depth reclamation (SFDR) base layer. For two sections, rejuvenator was incorporated to evaluate its impact on the performance of the cold recycled (CR) layer. Laboratory tests conducted after one year of service showed that even though rejuvenator improved binder fatigue resistance, its benefits were less evident at the mixture level, where cracking resistance declined. Perpetual pavement analysis indicated bottom-up cracking potential in all test sections but suggested that reasonable adjustments to overlay or CIR thickness could achieve perpetual behavior. The contrasting outcomes between binder, mixture, and Falling Weight Deflectometer (FWD) testing highlight the need for further research to fully understand the effect of rejuvenator on the CR layer/material behavior. Additional testing, focusing on fatigue, rutting, and low-temperature performance, is recommended to refine rejuvenator use in CIR applications and optimize cold recycling techniques for perpetual pavement construction.]]></description>
      <pubDate>Fri, 15 May 2026 17:15:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/2703795</guid>
    </item>
    <item>
      <title>Microstructural Evolution and In-Situ Deflection Behavior in Curing Cold Recycled Asphalt Mixtures Assessed by X-Ray Microtomography</title>
      <link>https://trid.trb.org/View/2701151</link>
      <description><![CDATA[This study evaluates the microstructural characteristics and mechanical behavior of cold recycled asphalt mixtures (CRAM) stabilized with asphalt emulsion throughout their curing period. A multi-scale experimental framework was employed, combining high-resolution X-ray micro-computed tomography with in-situ falling weight deflectometer (FWD) testing. Field-extracted specimens from four full-depth reclaimed pavement sections were scanned at multiple depths and curing ages to quantify air void (AV) morphology, distribution, and connectivity using deep learning-based digital image processing. Complementary FWD testing, conducted over a 263-day period, enabled the backcalculation of elastic moduli to monitor the progressive stiffness gain of the CRAM layers under field conditions. Results revealed significant heterogeneity in AV distribution, particularly in interface and base zones, which exhibited higher void counts and volumes compared with other layers. Deflection and modulus trends followed a three-phase trajectory: initial low stiffness, intermediate stabilization, and advanced structural gain, with moduli increasing from 300–700 MPa to over 3,000 MPa. The integration of microstructural and mechanical data revealed a strong correlation between AV network refinement and structural performance over time. These findings underscore the importance of curing protocols, compaction quality, and layer interaction in recycled pavement systems. The study demonstrates the value of combining advanced imaging with field testing to support performance-based design, quality control, and long-term durability of cold-recycled asphalt technologies.]]></description>
      <pubDate>Mon, 11 May 2026 12:24:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/2701151</guid>
    </item>
    <item>
      <title>Pavement-ME Rehabilitation Design Protocols for MDOT Implementation</title>
      <link>https://trid.trb.org/View/2696989</link>
      <description><![CDATA[This study delivers a Michigan-specific mechanistic-empirical framework for rehabilitation pavement design by locally calibrating Pavement ME Design (PMED) V2.6 across all major Michigan Department of Transportation (MDOT) rehabilitation fixes, including asphalt over asphalt/concrete/rubblized concrete/crushed asphalt, and concrete over asphalt/concrete. Using 14 field projects, falling weight deflectometer (FWD), ground penetrating radar (GPR), lightweight deflectometer (LWD), and field cores data were evaluated. The PMED materials inputs were established for existing aggregate base, sand subbase, pavements, crushed asphalt, rubblized concrete, and ASCRL asphalt mix. Calibration employed 336 pavement sections (308 asphalt, 28 concrete) and included fatigue cracking (top/bottom), rutting, transverse cracking (thermal + reflective), faulting, and IRI. Bootstrapping and reliability analyses produced revised local coefficients and standard-error equations that reduce bias relative to national defaults. Validation against AASHTO 93 showed calibrated PMED overlay thicknesses typically within ±1 to ±1.5 inches, aligning mechanistic predictions with current practice while improving sensitivity to materials, climate, and distress interactions. The PMED limitations were identified for some rehabilitation fix types, leading to recommended alternate layer inputs or modeling approaches. Sensitivity analyses also defined PMED input constraints, including minimum hot mix asphalt (HMA) overlay thicknesses of 3.5 inches over existing HMA and 4.5 inches over existing concrete pavements. Key outcomes include statewide layer modulus guidance, rehab-specific performance threshold recommendations, adoption of rehabilitation Level 2 inputs for HMA over HMA, and recommended design reliability levels to effectively integrate mechanistic-empirical rehabilitation design into MDOT standard practice.]]></description>
      <pubDate>Tue, 05 May 2026 10:18:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/2696989</guid>
    </item>
    <item>
      <title>Validation of Load-Deflection Linearity in Pavements Using Deflection Bowl Parameters</title>
      <link>https://trid.trb.org/View/2685704</link>
      <description><![CDATA[The present study evaluated the load–deflection linearity of pavements incorporating emulsion treated base layers using field deflection data. Seven pavement test sections constructed with different base layer compositions, including conventional granular base and emulsion treated base layers with varying emulsion content and reclaimed asphalt pavement incorporation, were investigated. Surface deflections were measured using a falling weight deflectometer under five impact load levels ranging from 30 kN to 70 kN. Deflection bowl parameters were used to estimate the contributions of the base, subbase and subgrade. Linear regression analysis showed strong linear relationships between load and deflection parameters, with coefficients of determination greater than 0.90 for all sections. Layer elastic moduli were estimated using back calculation and were observed to remain approximately constant within the investigated load range, with standard deviations less than 10% of the mean values. The results indicated that the pavement layers behaved elastically under the applied loading conditions. Deflections measured in sections with emulsion treated base layers were lower than those in the conventional base section, indicating improved stiffness. The findings confirm that linear normalization of deflection data can be reliably applied for structural evaluation within the load range of 30 kN to 70 kN.]]></description>
      <pubDate>Wed, 29 Apr 2026 17:05:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/2685704</guid>
    </item>
    <item>
      <title>Modelling of Deflection Basin Parameters of Asphalt Pavements Using Artificial Neural Networks and Adaptive Neuro-Fuzzy Inference Systems</title>
      <link>https://trid.trb.org/View/2579840</link>
      <description><![CDATA[Non-destructive testing equipment, such as the Falling Weight Deflectometer, offers crucial evaluations of the structural state of the road and enhances pavement management systems. Various approaches based on pavement surface deflection measured using Falling weight deflectometers are widely used around the world for assessing structural stability. The backcalculation of pavement layer moduli has been a widely recognized approach for assessing the structural adequacy of the pavement. However, consistently performing these tests at the network level is laborious, and the subsequent interpretation of the data requires technical expertise, a great deal of time, finance, and other resources. Because of this structural component of roadways, decisions when choosing between maintenance and repair are often neglected. This study uses a variety of structural, functional, environmental, and subgrade soil properties as input parameters to develop a trusted relationship for the estimation of seven different deflection basin parameters such as surface curvature index, Base Curvature Index, Base Damage Index, Area Under Pavement Profile, Deflection Ratio, Shape factors F1 and F2. An effective model was developed using artificial intelligence-based soft computing techniques; Artificial Neural Networks (ANN) and Adaptive Neuro-fuzzy Inference Systems (ANFIS) to predict the output deflection basin parameters from the input variables. The data to train, test and validate the model were gathered through field trials. To achieve the above goal, several models based on ANN and ANFIS were trained by changing number of hidden layers, the neurons in the layer and number of membership functions. Prediction efficiency of the model is assessed based on its root mean square error and the coefficient of determination value.]]></description>
      <pubDate>Tue, 28 Apr 2026 16:55:33 GMT</pubDate>
      <guid>https://trid.trb.org/View/2579840</guid>
    </item>
    <item>
      <title>Performance Assessment of Premix Carpet for Low-Volume Roads</title>
      <link>https://trid.trb.org/View/2579838</link>
      <description><![CDATA[The paper presents the performance of premix carpet for low-volume roads in terms of structural capacity and functional properties. The structural capacity was evaluated using falling weight deflectometer (FWD). International roughness index (IRI) was used as a measure of the functional property. A total of 26 sections with a total road length of 110 km were selected for the study. At each test location, pavement composition was determined by excavating test pit along the edge of the shoulder. Subsequently, FWD test was conducted. Deflections were measured at 8 radial distances, ranging from 0 to 1500 mm. Deflection values ranged between 475 and 1129 μm below the loading plate and 30–224 μm at radial distance of 1500 mm. Using deflection readings, structural number (SN) and deflection bowl parameters including surface curvature index (SCI), base damage index (BDI), base curvature index (BCI) and AREA were calculated. Then, IRI was measured using Roughometer III device. IRI progression with time indicated that for a trigger value of 4.62 m/km, premix carpet roads would require maintenance after 41 months of service life. In addition, a good correlation between the deflection bowl parameters and IRI was observed. So, the limits of IRI were used to propose the recommended range of deflection bowl parameters. It was found that when the values of SCI, BDI and BCI increase to more than 313, 152 and 58, respectively, or AREA and SN reduce to less than 447 and 17, respectively, the pavement exhibits poor condition and would require rehabilitation.]]></description>
      <pubDate>Tue, 28 Apr 2026 16:55:33 GMT</pubDate>
      <guid>https://trid.trb.org/View/2579838</guid>
    </item>
    <item>
      <title>Forensic Investigation of Sections</title>
      <link>https://trid.trb.org/View/2187218</link>
      <description><![CDATA[The Ohio Strategic Highway Research Project (SHRP) Test Road, constructed on U.S. 23 about 25 miles (40 km) north of Columbus, Ohio, consists of forty test sections in the SHRP SPS-1, SPS-2, SPS-8, and SPS-9 experiments. During the summer of 2002, after the appearance of localized distress in Section 390103, a forensic study of this and Sections 390108, 390109, and 390110 in the SPS-1 (Asphalt Concrete) experiment was completed through a series of destructive and non-destructive tests. Distress surveys were conducted on these four sections in accordance with SHRP-P-338 "Distress Identification Manual for the Long-Term Pavement Performance Project." Non-destructive testing included Falling Weight Deflectometer (FWD), transverse profiling, and Dynamic Cone Penetration tests (DCP). Trenches were excavated at locations with various levels of distress to measure transverse layer profiles, and to obtain material samples for laboratory testing. Collected data was analyzed to determine the causes of localized distresses. The investigation revealed substantial variability in stiffness and high levels of moisture in the subgrade soil at all four pavement sections. These trends indicate that the severity of distress in Sections 390108, 390109, and 390110 would soon be similar to those in Section 390103 if the sections were left open to traffic. Despite the use of various base materials and the presence of edge drains in Sections 390108, 390109 and 390110, higher than anticipated levels of subgrade soil moisture reaching saturation were present in all four pavement sections. Excessive moisture was determined to be the underlying cause of rutting and cracking. While edge drains probably removed some moisture infiltrating down from the pavement surface, they provided little relief from moisture migrating up through the subgrade.]]></description>
      <pubDate>Mon, 27 Apr 2026 15:01:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/2187218</guid>
    </item>
    <item>
      <title>Testing and Microcracking Assessment of Cement-Treated Full-Depth Reclamation</title>
      <link>https://trid.trb.org/View/2695843</link>
      <description><![CDATA[Full-depth reclamation (FDR) has gained increasing recognition as an efficient and cost-effective pavement rehabilitation method by recycling up to 100% of existing materials on-site, with Portland cement-stabilized FDR (FDR–PC) providing enhanced structural integrity. A comprehensive understanding of the mechanical properties of FDR–PC is essential to optimize its design and improve implementation efficiency. This study investigated the mechanical characteristics of FDR–PC, the interrelationships among various tests, and assessed the use of microcracking on constructed accelerated pavement test sections. Tests conducted included compressive strength (CS), flexural strength, elastic modulus, and shrinkage behavior in the laboratory, and deflection testing using a falling weight deflectometer. Four constructed FDR–PC pavement sections, including 3.25% and 5.5% cement content (by weight), both with and without induced microcracking, were built to study the shrinkage concerns observed during practice associated with FDR–PC. In addition, the influence of the microcracking technique was evaluated. The findings include: (1) a correlation factor of 1.46 to account for specimen-size effects in FDR–PC CS testing; (2) a slower loading rate than that specified in ASTM C469 may be more appropriate for characterizing FDR–PC; (3) the American Concrete Institute-based modulus predictions tend to overestimate FDR–PC stiffness; (4) the American Association of State Highway and Transportation Officials model provided the most accurate 7-day modulus of rupture (MoR) estimates; (5) length change test results were influenced by density and cement content; (6) strong correlations were observed among all evaluated mechanical properties; and (7) microcracked mixtures gained stiffness over time, with greater initial reduction in the lower-stiffness FDR–PC and significant stiffness recovery in the high-stiffness FDR–PC.]]></description>
      <pubDate>Mon, 27 Apr 2026 15:00:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/2695843</guid>
    </item>
    <item>
      <title>Measuring Long-Term Performance of Unbonded Concrete Overlay Pavement in Florida</title>
      <link>https://trid.trb.org/View/2663265</link>
      <description><![CDATA[Concrete overlays have gained more attention due to their ability to extend the service life of deteriorated pavements and provide a smooth riding surface. This study focused on investigating the long-term performance of unbonded concrete overlay pavements in terms of structural performance, cracking performance, faulting performance, and smoothness (IRI) by utilizing the falling weight deflectometer (FWD) and laser crack measurement system (LCMS). The field data was collected over the last thirty-five years on an unbonded concrete overlay testing road on US-1 between Daytona Beach and Titusville. The test road was constructed by Florida Department of Transportation (FDOT) in 1988. A total of 3.06 km of concrete overlay was included in a 12.9 km milling and resurfacing project for a deteriorated asphalt pavement. The concrete overlay test sections were divided into three groups based on design thickness. Each group had subsections with three joint spacing levels and two dowel bar configurations (standard 30.5-cm spacing and wheel path only). It was found that the studied experimental concrete overlay sections outlived the design life with only minor repair and rehabilitation requirements after 35 years of service with more than 2.95 million truck passes. Thicker concrete overlay slabs provided better overall performance. Shorter slab lengths mitigated slab cracking. The slabs with dowels in the wheel path configurations could not provide comparable performance to the slabs with standard dowel bar configuration. A five-point rating scale was employed to assess long-term pavement performance with various design configurations. A multiple regression analysis was performed to identify significant pavement design parameters that affect pavement performance in terms of structural capacity, corner deflection, load transfer efficiency (LTE), cracking, international roughness index (IRI), and faulting. The findings from this study can support the development of comprehensive concrete overlay design approaches in Florida.]]></description>
      <pubDate>Mon, 27 Apr 2026 15:00:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/2663265</guid>
    </item>
    <item>
      <title>Backcalculated Dynamic Modulus Master Curve from the Time Histories of Falling Weight Deflectometer Surface Deflections</title>
      <link>https://trid.trb.org/View/2691785</link>
      <description><![CDATA[Accurate structural evaluation of flexible pavements is important for cost-efficient maintenance and rehabilitation (M&R) strategies. Traditional back-calculation methods based on Falling Weight Deflectometer (FWD) data assume elastic behavior, overlooking the viscoelastic nature of asphalt materials and subsequently leading to inaccuracies. This study introduces a mechanistic-based back-calculation technique to estimate the dynamic modulus (E*) master curve directly from FWD time-history data. By integrating layered elastic theory with viscoelastic principles, the proposed method first determines the relaxation modulus, E(t), using Differential-Time Fourier Transform (DTFT) analysis. This time-domain response is then converted into the frequency domain to construct the E* master curve. Validation against laboratory-measured dynamic modulus values from field-cored specimens demonstrates that the proposed technique generates highly accurate E* master curves for all asphalt layers. Moreover, the findings highlighted the importance of accurate pavement structural information, such as layer thickness and Poisson’s ratio, for achieving reliable E* master curve.]]></description>
      <pubDate>Mon, 20 Apr 2026 09:22:54 GMT</pubDate>
      <guid>https://trid.trb.org/View/2691785</guid>
    </item>
    <item>
      <title>SPR-5031: Developing INDOT Road Crack Image Datasets for Advanced Analytics Research</title>
      <link>https://trid.trb.org/View/2691526</link>
      <description><![CDATA[The Indiana Department of Transportation (INDOT) requires a comprehensive, annotated crack image dataset from falling weight deflectometer (FWD) testing to enable advanced analytics for pavement management. This project delivers systematically labeled crack images to correlate with structural deflection data, and standardized annotation protocol. Dataset enables automated crack detection, enhanced structural assessment capabilities, and data-driven pavement management decisions while leveraging existing image archives cost-effectively through annotators.]]></description>
      <pubDate>Wed, 06 May 2026 14:55:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/2691526</guid>
    </item>
    <item>
      <title>Utilizing Grasspaver-Geocell as a Recycled Reinforcement Material in Flexible Pavement Base Layers: A Field Investigation</title>
      <link>https://trid.trb.org/View/2651475</link>
      <description><![CDATA[Geosynthetic materials, predominantly made from virgin synthetic polymers like high-density polyethylene (HDPE), are widely used to enhance pavement performance. However, growing environmental concerns surrounding plastic waste accumulation and pollution necessitate sustainable alternatives. This study investigates the application of the grasspaver-geocell, a recyclable geosynthetic material produced from HDPE waste, to address the problems of plastic waste and advance sustainable civil infrastructure. The investigation involved constructing three full-scale pavement sections in Dholera, Gujarat, India, including one reinforced with grasspaver-geocells, another with virgin HDPE-based geocells, and an unreinforced section. All sections comprised three layers, i.e., a lime-treated subgrade (6% lime), a subbase, and a base layer. The reinforcement materials (grasspaver-geocell and geocell) were placed within the base course. Plate load testing and falling weight deflectometer analysis were performed on all sections. Results indicate that the grasspaver-geocell reinforced section achieved a 40% higher load-bearing capacity, a 34% reduction in subgrade stress, and a 40%–60% improvement in the modulus of subgrade reaction compared to the unreinforced section. However, compared to the geocell-reinforced section, the grasspaver-geocell exhibited a 13% lower load-bearing capacity, 14% higher subgrade stress, 15% lower modulus of subgrade reaction, and 30% higher strain value at cell wall due to differences in height, seam strength, and surface texture. Despite these disparities, grasspaver-geocell reinforcement still demonstrated notable performance improvements over weak subgrades. The modulus improvement factor was 1.79 for the grasspaver-geocell and 1.98 for geocell-reinforced sections. Also, the annual greenhouse gas emissions ratio for the grasspaver-geocell reinforced sections was 46% lower than the unreinforced section and 2% lower than the geocell-reinforced section. The outcomes highlight the potential of grasspaver-geocell reinforcement as a viable and sustainable alternative for enhancing pavement performance on weak subgrades.]]></description>
      <pubDate>Tue, 31 Mar 2026 16:35:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/2651475</guid>
    </item>
    <item>
      <title>Research on connection stiffness and load transfer performance of precast assembled pavement panels</title>
      <link>https://trid.trb.org/View/2651542</link>
      <description><![CDATA[Prefabricated pavement systems provide a novel approach for rapid construction of airport pavement. It is worth further research on the connection stiffness and load transfer performance of prefabricated pavements with limited connection points. Currently, there is a lack of research on full-scale plate testing and dynamic load analysis in the assessment of joint stiffness and load transfer capacity for such pavements. Based on the design of prefabricated pavement panels at Guangzhou Baiyun International Airport, this paper conducted a falling weight deflectometer (FWD) test on a full-scale pavement model. The deflection at the bottom of prefabricated panels was measured, and the load transfer coefficients were calculated. By finite element simulations of transient dynamics and static mechanics, a comparative analysis of testing and finite element simulating results under static and dynamic loads was carried out. By introducing a connection stiffness coefficient, it was found that the relationship between the connection stiffness coefficient and the load transfer coefficient of deflection followed an “S”-shaped curve, and two formulas were fitted for simplified calculation of the load transfer coefficient in prefabricated pavements. Based on equivalent calculations of joint stiffness and comparisons with the test results, it was suggested that load transfer through connecting steel bars to the surrounding area did not follow a linear pattern. Additionally, even without panel connections, a load transfer coefficient of 20% to 30% can be achieved relying solely on the monolithic base layer, and this value was independent of the modulus of reaction at the base. The research contributes to the design of joint stiffness and the calculation of load transfer coefficients in prefabricated pavements, thereby ensuring their practical engineering applications.]]></description>
      <pubDate>Tue, 31 Mar 2026 10:13:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/2651542</guid>
    </item>
    <item>
      <title>Performance Evaluation of Cell-Filled Concrete Pavements in Rural Roads of Odisha</title>
      <link>https://trid.trb.org/View/2678105</link>
      <description><![CDATA[Rural roads constitute one of the largest road networks in India. The choice of construction materials and technologies for these roads can significantly impact their carbon footprint. India's rural roads have implemented several new pavement technologies to reduce the carbon footprint without compromising performance. Cell-Filled Concrete Pavements (CFCP) are one such new technology, which consists of plastic cells filled with cement concrete. This technology eliminates the need for contraction, construction, and other types of joints, thereby reducing costs and the need for maintenance. Past studies on CFCP in India have mainly focused on the structural aspects without giving due importance to overall performance. This study investigated the structural and functional performance of twelve sections of CFCP in Odisha. Further, laboratory investigations were conducted on the material obtained from the field. The concrete core study indicated that porosity was relatively higher, resulting in reduced ultrasonic pulse velocity and in-situ compressive strength, as estimated by a rebound hammer. The condition survey indicated that edge breaking, raveling, and rutting were predominant distresses, which need special attention. Furthermore, Falling Weight Deflectometer (FWD) studies have highlighted the importance of a strong base layer and higher field dry density in the subgrade layer for improved structural performance. Based on the findings, the study recommends a cross-section of CFCP with edge restraint and low-slump (< 40 mm) concrete for enhanced performance.]]></description>
      <pubDate>Mon, 30 Mar 2026 08:55:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/2678105</guid>
    </item>
    <item>
      <title>Sensitivity of Initial//Seed Moduli for Overlay Design of Flexible Pavement</title>
      <link>https://trid.trb.org/View/2678110</link>
      <description><![CDATA[The initial selection of elastic modulus (E) value ranges for pavement layers has a significant influence on the performance of back-calculation software, such as KGP BACK, which is commonly used in India. These initial E values not only affect the accuracy of back-calculated results but also have a direct impact on the determination of overlay thickness in pavement rehabilitation design. This paper investigates the relationship between the selected range of E values and the resulting overlay thickness, with a specific focus on how variations in initial modulus values affect back-calculation outcomes. It is noteworthy that IRC:115-2014 could also include guidance on the use of Deflection Basin Parameters (DBPs) for Falling Weight Deflectometer (FWD) analysis of different types of flexible pavement. To ensure reliable analysis, the range of E values shall be selected such that the difference between the measured deflections (FWD) and the theoretical deflections (calculated using IITPAVE software) is minimized. This is achieved by minimizing the sum of squared differences or more effectively, by minimizing the Root Mean Square Error (RMSE) between measured and calculated deflections. The IITPAVE software has been used to compute theoretical surface deflections at sensor positions corresponding to FWD geophone locations, assuming a single-wheel load of 40 kN and a loading plate diameter of 300 mm. A case study was carried out by varying the E value ranges of pavement layers, and the corresponding surface deflections and overlay thicknesses were determined and analyzed. The results reveal that overlay thickness varies from 80 mm to 135 mm, depending on the initial E values used. This variability underscores the importance of selecting appropriate E value ranges and suggests a potential need for revising the overlay thickness determination approach within FWD-based structural evaluations. IRC:81 and similar method proposed in Austroads Part 5 may be followed.]]></description>
      <pubDate>Mon, 30 Mar 2026 08:55:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/2678110</guid>
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