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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>
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    <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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      <link>https://trid.trb.org/</link>
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    <item>
      <title>Measurement of Cement Content and Layer Thickness Variation of Cement-Stabilized Base and Subgrade Using Ground Penetrating Radar</title>
      <link>https://trid.trb.org/View/2681205</link>
      <description><![CDATA[This report presents a comprehensive methodology for evaluating cement content and layer thickness variability in cement-stabilized pavement layers using a nondestructive ground penetrating radar (GPR) technique. The research integrates laboratory calibration and field validation for two widely used stabilization practices: conventional soil-cement stabilization and full-depth reclamation (FDR). Laboratory work involved preparing soil-cement/FDR specimens with varying cement and moisture contents, compacted to field-representative densities. The specimens were tested daily for over an 8-day curing period using dielectric constant and electrical conductivity measurements to track the hydration process. A field GPR survey was conducted at several Georgie Department of Transportation (GDOT) project sites in Albany, Conyers, and Peachtree City, as well as Henry County, using a 2-GHz air-coupled antenna. Dielectric constants were obtained from GPR scans, and electrical conductivity was derived through the Crockford et al. (2021) model. Cement content estimation was performed by matching the field electrical conductivity values to the corresponding laboratory-derived surfaces. The estimated cement content at the soil-cement and FDR sites ranged between 4 and 7 percent. Although some sites showed results consistent with the running average, others exhibited estimated cement contents exceeding or falling below the design mix, indicating non-uniform cement application across the sites. These findings highlight the importance of developing a reliable quality control and quality assurance framework to ensure consistent and verifiable material performance in the field.]]></description>
      <pubDate>Thu, 19 Mar 2026 08:56:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/2681205</guid>
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    <item>
      <title>Deformation Mechanisms of Sulfate–Saline Soil Subgrades in Cold Arid Regions: Thermal Differential Responses in Pavement Structural Layers</title>
      <link>https://trid.trb.org/View/2620548</link>
      <description><![CDATA[To investigate the deformation characteristics of coarse-grained sulfate–saline soil subgrades to the thermal responses of pavement structures in cold arid environments with significant diurnal temperature variations, this study focuses on a highway located in the Tarim Basin in Northwest China. Three test sections (K-I, K-II, and K-III) were constructed, each featuring distinct configurations of pavement base layers. The designs of these sections depend on the characteristics of the pore structure and cement content. Multifactor monitoring of moisture, heat, salt, and mechanics was conducted to evaluate the deformation behavior of the subgrade under varying thermal conditions. Section K-I with the insulated low-cement-dosage skeleton-dense gradation (insulated LC-SDG) base exhibits the smallest daily temperature amplitude of 3.1°C and low thermal sensitivity. Section K-III with the pavement base of high-cement-dosage suspension-dense gradation (HC-SusDG) displays the highest thermal sensitivity, recording an annual temperature amplitude that exceeds that of Section K-II (LC-SDG) and Section K-I by 2.5%–4.0%. This intensifies the phase transition in high-sulfate subgrade soils of Section K-III, where the latent heat released during crystallization slows the temperature decline at the subgrade surface during cooling periods. In Section K-III, pronounced dissolution-crystallization cycles of moisture and salt, coupled with steep thermal gradients, result in excessive moisture-salt accumulation beneath the upper impermeable layer, which is 6.9–15.4 times higher than that in Sections K-II and K-I. Consequently, the subgrade surface experiences a peak soil pressure of 229.6 kPa, cyclic pressure amplitudes of 3.7 kPa, and salt-induced pressure increments of 3.4 kPa in Section K-III. These stresses promote the accumulation of tensile strain, and during the optimal salt heaving period (December–February), the peak reaches only 212.8 × 10⁻⁶ at the subbase of Section K-I. The thermal regulation and cement content-optimization of pavement structures are critical for mitigating the deformation of sulfate–saline soil subgrades in cold arid regions. These findings provide theoretical guidance for enhancing regional pavement design and construction techniques.]]></description>
      <pubDate>Tue, 17 Feb 2026 13:12:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/2620548</guid>
    </item>
    <item>
      <title>The freeze-thaw deformation and inter-layer interface contact characteristics of toughened cement stabilized macadam: an experimental study based on the high-speed railway subgrade</title>
      <link>https://trid.trb.org/View/2630915</link>
      <description><![CDATA[The research involved replacing fine particles with solid waste rubber powder to prepare the toughened cement stabilized macadam/TCSM. Based on vertical full-scale model tests of frost heave and thaw settlement, vertical stress transmission tests between layers, and inter-layer interface adhesion effect evaluation tests, the freeze-thaw deformation and inter-layer interface contact characteristics of TCSM were discussed. The results indicated: 1) Under test conditions where cement and rubber powder were added simultaneously, the TCSM could effectively eliminate thaw settlement deformation, with frost heave deformation reduced from 2.53mm to 0.26mm, a decrease of 90.4%. The hydration and adhesion of cement, combined with the elastic filling of rubber powder, played a positive role in resisting volume deformation caused by ice-water phase transitions. 2) The contact area between the TCSM and the surface of the sub-grade fill material was more extensive than that of cement stabilized macadam under the same conditions, exhibited better stress diffusion behaviour. Under low stress conditions, stress diffusion effects were pronounced, while under high stress conditions, stress concentration continued to increase. 3) Under identical micro-deformation conditions, the fixed interface bending load-bearing capacity was 4 times that of a free interface for the composite inter-layer structure, and a calculation method for the interface adhesion contact coefficient/IBC was provided. The TCSM shown the better inter-layer adhesion effect when combined with SBS/rubber powder blended modified asphalt mixture, with an index value of 3.9 under small deformation conditions of 0.2mm, approaching the ideal fixed state. The research could understand the freeze-thaw deformation characteristics and its contact state with the upper and lower layers for TCSM, which was crucial for enhancing the toughness of the subgrade surface layer.]]></description>
      <pubDate>Mon, 22 Dec 2025 17:03:49 GMT</pubDate>
      <guid>https://trid.trb.org/View/2630915</guid>
    </item>
    <item>
      <title>Resilient Modulus Characteristics of Cement-Treated Recycled Concrete Aggregates</title>
      <link>https://trid.trb.org/View/2562211</link>
      <description><![CDATA[The construction and demolition activities have been increasing drastically due to the rapid expansion of new infrastructure generating enormous volumes of concrete waste. The generated concrete wastes are typically dumped into the landfills resulting in numerous negative environmental impacts. Recycled concrete aggregates (RCA) processed into different sizes of aggregates can be employed in the construction of pavement base and subbase layers, enabling to lower the demand for virgin aggregates. In this study, unbound RCA is found to meet the particle-size distribution, and Los Angeles abrasion in accordance with various road standards such as Indian Road Congress (IRC) and the American Association of State Highway and Transportation Officials (AASTHO) for pavement base/subbase layer materials. This study investigates the resilient modulus characteristics of cement-treated (3%, 5%, and 7% cement content by weight of dry aggregates) RCA for base/subbase layer applications. Resilient modulus tests are performed under varying stress levels and cement contents to evaluate the material’s behavior under cyclic loading conditions. The results showed an increase in the resilient modulus values with increasing cement content. For the treated samples considered in the study, 7% cement-treated RCA showed maximum resilient modulus value (676 MPa) at 7 days of curing. Additionally, the impact of longer curing time on resilient modulus characteristics is investigated, and it is found that resilient modulus values are typically enhanced with increasing curing period. Overall, the findings of the study suggest that RCA can be a sustainable alternative to virgin aggregates, which offers potential benefits in terms of sustainability and conservation of natural resources.]]></description>
      <pubDate>Thu, 21 Aug 2025 09:19:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/2562211</guid>
    </item>
    <item>
      <title>Influence of Cement and Emulsion Content on the Mechanical Response of Cold Recycled Mixtures</title>
      <link>https://trid.trb.org/View/2582062</link>
      <description><![CDATA[The current study investigates the influence of cement and emulsion dosage on the evolution of the volumetric and mechanical properties of cold recycled mixtures. Four mixtures with varying emulsion and cement dosages were prepared, having different emulsion-to-cement (E/C) ratios. The volumetric and mechanical properties were monitored at 3, 7, and 14?days of curing. The mechanical properties were measured through a repeated haversine compression test at different temperatures (10°C, 20°C, 30°C, and 40°C) and frequencies (25, 20, 10, 5, 2, 1, 0.5, 0.2, 0.1, and 0.01?Hz). It was seen that mixtures with a 1% increase in cement dosage influences the mechanical properties substantially more than a 1% increase in emulsion content. The viscoelastic response of the mixtures was evaluated using master curve and relaxation spectrum. Mixtures with lower E/C ratios showed higher dynamic modulus over the considered frequency range, particularly at initial curing days. The storage modulus is primarily influenced by cement dosage, whereas the loss modulus is affected by both the cement and emulsion contents. The influence of emulsion on the mixture was observed through the loss modulus master curve and relaxation characteristics. Based on the observation of moisture loss and air void variation over different curing periods, it is concluded that curing not only leads to the depletion of moisture but also facilitates volume changes as a result of cement hydration. Overall, as curing progresses, there is an increase in air voids; however, emulsion breaking and cement hydration enhance the mechanical response.]]></description>
      <pubDate>Fri, 25 Jul 2025 11:31:29 GMT</pubDate>
      <guid>https://trid.trb.org/View/2582062</guid>
    </item>
    <item>
      <title>Utilizing Dielectric Constant and Electrical Conductivity to Estimate Cement Content in Stabilized Subgrade Soils</title>
      <link>https://trid.trb.org/View/2543897</link>
      <description><![CDATA[Cement stabilization is a standard method used to strengthen fine-grained soils that are locally available and prepare them for pavement construction. Flexible pavements over cement-stabilized soils commonly experience mild reflective cracking originating from the shrinkage cracks on top of the stabilized layer. The severity of this form of reflective cracking is correlated to inadequate soil–cement construction practices which include thin stabilized layers, low compaction, deviations in cement content from the mix design, and rapid moisture loss. Consequently, these construction issues can significantly reduce the flexible pavement strength and overall life cycle. In this study, a non-destructive quality assurance method using a ground penetrating radar (GPR) and percometer was developed to capture stabilized soil’s inconsistent cement content and hydration rates. A predictive model derived from laboratory testing was created based on the distinct hydration rates, dielectric constants, and electrical conductivities associated with different water and cement contents. Laboratory testing shows that GPR can detect these inconsistencies in cement-stabilized layers within the first seven days after construction through non-destructive testing.]]></description>
      <pubDate>Wed, 21 May 2025 09:52:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/2543897</guid>
    </item>
    <item>
      <title>Performance Evaluation of Cement Modified Asphalt Rubber Binder through Optimizing Aging Indexes</title>
      <link>https://trid.trb.org/View/2534671</link>
      <description><![CDATA[With increasing heavy traffic loads and expanding transportation networks, the engineering quality of asphalt pavements must be continuously improved. Previous research has shown that waste tire rubber and cement can enhance the overall properties of asphalt binders and mixtures. However, the performance evaluation of cement and rubber-modified asphalt binders, especially in terms of aging characteristics, remains unclear. This study investigates the appropriate aging index to evaluate the modification effects of combining cement and rubber in asphalt binders using thermal oxygen aging tests. A series of chemical and rheological tests, including Fourier Transform Infrared (FTIR) Spectroscopy, Dynamic Shear Rheology (DSR), softening point, and penetration, were conducted. Various aging indexes were compared through orthogonal optimization analysis. Results indicated that cement content up to 2.5% enhances the high-temperature stability and hardness of CRMA binders, with a 6.7% increase in softening point and a 4.7% decrease in penetration. However, excessive cement content (above 2.5%) leads to particle agglomeration, reducing penetration by 21% and accelerating aging degradation. Rheological analysis showed that thermal oxidative aging and moderate cement content improve high-temperature deformation resistance. Among the developed aging indexes, the rutting factor index (RFI) exhibited the lowest variance, confirming its reliability for evaluating modification effects. This study provides crucial insights for optimizing aging indicators and improving the durability of asphalt binders.]]></description>
      <pubDate>Thu, 24 Apr 2025 09:30:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/2534671</guid>
    </item>
    <item>
      <title>Experimental elucidation of temperature and loading rate effects on the shear behavior of cement-emulsified asphalt mortar</title>
      <link>https://trid.trb.org/View/2493582</link>
      <description><![CDATA[The shear behavior of cement emulsified asphalt (CA) mortar is of importance for ensuring resilience against horizontal stresses induced by high train velocities, particularly on steep inclines, declines, or off-tracking situations where complex stress states involve principal stress planes and interactions of normal and horizontal forces. The objective of this study was to investigate the shear stress-strain characteristics of CA mortar under varying asphalt-to-cement (A/C) ratios (0.5, 0.7, 0.9), temperatures (5°C, 25°C, 50°C), and loading rates (0.5, 5, 50 mm/min). This approach facilitated the elucidation of shear strength, shear modulus, and fracture energy. The findings indicate that temperature and loading rate have a significant impact on the shear behavior of CA mortar. The shear strength exhibited an increase with higher loading rates and a decrease with rising temperatures across all asphalt-to-cement (A/C) ratios. Specifically, an increase of up to 40 % in shear strength was observed when the loading rate was increased from 0.5 to 5.0 mm/min at 5°C, while a decrease of approximately 1.47 MPa per °C increase in temperature was noted. As the A/C ratio increased from 0.5 to 0.7, a decrease in shear strength was observed, with a range of 30–41 % at the 45° angle. The results demonstrated that lower A/C ratios yielded higher shear modulus at all temperatures, with an increase of up to 44 % observed when the A/C ratio decreased from 0.7 to 0.5. Additionally, significant interaction effects were observed, indicating that the positive effect of increased loading rate on shear strength was amplified under warmer conditions due to the interaction between temperature and loading rate. Similarly, the interaction between temperature and A/C ratio influenced shear modulus and fracture energy, underscoring the intricate, nonlinear interdependencies among these factors. Fracture energy decreased with increasing A/C ratio and temperature, decreasing by 9.67 J/m² per °C increase, while it increased with higher loading rates. The maximum fracture energy was observed at 5 °C with an A/C ratio of 0.5. The ANOVA at a 5 % significance level confirmed that temperature, loading rate, and A/C ratio, as well as their interactions, significantly influenced the shear properties of CA mortar. These findings highlight the necessity of considering the combined effects of temperature, loading rate, and A/C ratio in CA mortar design and predictive models.]]></description>
      <pubDate>Tue, 04 Mar 2025 15:11:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/2493582</guid>
    </item>
    <item>
      <title>Fatigue characteristics of cement-stabilized steel slag base course for asphalt pavement structure considering different paving methods</title>
      <link>https://trid.trb.org/View/2487657</link>
      <description><![CDATA[This study investigates different on-site paving methods for the base course, establishing a model using the computational programme GAMES based on the elastic layered system theory. The impact of the number of paving layers, paving thickness and the bonding condition at interfaces between sub-layers on the fatigue characteristics of the asphalt pavement structure with the cement-stabilized steel slag (CSS) base course is investigated. Furthermore, this study explores the impact of factors such as forming method, curing time and cement content on the fatigue characteristics of the CSS mixtures through laboratory indirect tensile test. The results indicate that the impact of the bonding conditions at paving interfaces between sub-layers due to layered paving on the tensile stress at the bottom of the CSS base course is much greater than that of the asphalt surface course. The tensile stress at the bottom of the CSS base course increases first and then decreases as the paving interface moves from top to bottom, indicating the existence of the most unfavourable paving interface. It is recommended to use vibration compaction method for forming the CSS base course to reduce the paving interface, thereby enhancing the fatigue resistance of the pavement structure.]]></description>
      <pubDate>Mon, 10 Feb 2025 17:11:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/2487657</guid>
    </item>
    <item>
      <title>Cold asphalt mix with emulsion and 100% rap: Compaction energy and influence of emulsion and cement content</title>
      <link>https://trid.trb.org/View/2454434</link>
      <description><![CDATA[The present work aims at determining the conditions for the compaction of cold recycled mixtures with emulsion and 100% RAP. Additionally, the influence of the emulsion and cement on the final properties of the recycled mixtures has been investigated. To achieve these purposes, reclaimed asphalt material coming from the milling of a distressed pavement was mixed with different proportions of water, asphalt emulsion and cement. The mixtures were compacted by a gyratory compactor. As a result of the investigation, it is recommended to apply a compaction energy level of 100 gyrations for specimens 100 mm diameter and 60 mm height, and an energy of 200 gyrations for specimens 100 mm diameter and 100 mm height. As for the mechanical properties of the mixtures, the laboratory tests showed that the presence of cement contributes to improving the sensitivity to water attack, the resistance to permanent deformations, the stiffness modulus and the fatigue life of the mixtures.]]></description>
      <pubDate>Wed, 11 Dec 2024 10:39:05 GMT</pubDate>
      <guid>https://trid.trb.org/View/2454434</guid>
    </item>
    <item>
      <title>Dynamic Shear Strength Characteristics of EPS Lightweight Soil</title>
      <link>https://trid.trb.org/View/2452720</link>
      <description><![CDATA[This study examines the dynamic shear strength properties of expanded polystyrene lightweight soil (EPS LWS) samples through dynamic triaxial tests, focusing on the effects of EPS bead content, cement concentration, and confining pressure. The results indicate that increasing the cement content positively correlates with the dynamic strength of EPS LWS due to the formation of reticulate cement hydrates that bond soil particles. When the cement content is below 10%, EPS beads have minimal impact on dynamic shear strength. However, at cement contents of 15% or higher, increasing EPS bead content reduces dynamic strength because the low-strength EPS beads break under these conditions. Elastic deformation in EPS LWS remains stable, with elastic strain increasing as EPS particle content and confining pressure rise. This highlights the significant impact of these factors on elastic strain, which is crucial for achieving the desired density and strength in engineering applications. The nonlinear behavior under dynamic stress and strain, showing strain hardening at critical levels. Higher EPS content reduces the dynamic stress required for bearing capacity due to decreased stiffness. Additionally, the dynamic elastic modulus increases with cyclic loading frequency, while higher confining pressure enhances hoop stress effects, requiring more dynamic stress to achieve the same strain. This study provides insights into the dynamic shear strength properties of EPS LWS, emphasizing the critical roles of cement content, EPS bead content, and confining pressure in influencing its performance in engineering applications.]]></description>
      <pubDate>Tue, 19 Nov 2024 14:38:09 GMT</pubDate>
      <guid>https://trid.trb.org/View/2452720</guid>
    </item>
    <item>
      <title>Low-Cement Concrete Mixture for Bridge Decks and Rails</title>
      <link>https://trid.trb.org/View/2394461</link>
      <description><![CDATA[Right after construction, drying shrinkage of restrained concrete bridge decks and rails causes early-age cracking, insertion of water and chemicals, and corrosion of reinforcing steel that eventually leads to delamination and spalling of concrete. The main objective of this research is to control early-age shrinkage cracking by reducing cementitious material content in bridge deck and rail concrete mixtures. Several reduced cementitious materials concrete (RCMC) mixtures were developed by optimizing aggregate particle packing and conducting overall performance evaluation. This evaluation was carried out in three phases. The first phase investigated the feasibility of new RCMC mixtures by testing workability, compressive strength, and chloride penetrability when cementitious materials content is reduced by 50, 100, and 150 lbs per cubic yard compared to the standard bridge deck concrete mixture of Nebraska. The second phase investigated fresh properties (slump and air content), early-stage properties (setting time and heat of hydration), mechanical properties (compressive strength, modulus of rupture, modulus of elasticity, shear strength, slant shear strength, and bond strength), durability properties (freeze and thaw resistance, and chloride resistivity), and shrinkage properties (free and restrained shrinkage). The third phase investigated the batching, mixing, handling, pumpability, and finishing of the RCMC mixtures by casting mockup deck panels using ready mixed concrete. All the developed RCMC mixtures have demonstrated a comparable performance to the standard mixture while having a reduced cementitious materials content, which is expected to reduce production cost and carbon footprint due to the lower cement content.]]></description>
      <pubDate>Mon, 24 Jun 2024 09:26:17 GMT</pubDate>
      <guid>https://trid.trb.org/View/2394461</guid>
    </item>
    <item>
      <title>Research on Rapid Curing Technology of Lime-Flyash-Cement Stabilized Macadam</title>
      <link>https://trid.trb.org/View/2203468</link>
      <description><![CDATA[In order to solve the problem of long curing time and long construction time of projects, the early strength of lime and fly-ash stabilized macadam can be increased by applying the proper amount of cement. First, compressive strength, cleavage strength and compression rebound modulus of lime-fly ash-cement stabilized macadam are tested systematically applying standard curing (T: 20±2°C, RH: ≥95%) and high-temperature curing (T: 60±2°C, RH:≥95). Secondly, a relationship curve between strength and curing age is found by applying four different regression models. Thirdly, strength gain relationship between high temperature curing and standard curing is achieved. So, the 180-day strength by standard curing can be determined from the strength cured by high temperature curing. Fourthly, the microstructure of samples is observed and analyzed systematically by applying electron microscope scanning. By the way of high temperature curing, not only can the microstructure of it be improved, but also the curing time can be shortened. Therefore, design parameters and major control index of ratio design for the lime-fly ash-cement stabilized macadam base course construction can be confirmed rapidly.]]></description>
      <pubDate>Mon, 17 Jun 2024 14:45:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/2203468</guid>
    </item>
    <item>
      <title>Revised Curing Practices for NDOT Bridge Decks to Minimize Restrained Shrinkage Cracks</title>
      <link>https://trid.trb.org/View/2387169</link>
      <description><![CDATA[Due to their high cement content and low water-to-cement ratio, cast-in-place concrete bridge decks are particularly susceptible to early-age cracking. This is often exacerbated by the shrinkage of the concrete when constrained by supporting girders. Such cracks can lead to significant issues, such as rebar corrosion and delamination, posing a primary concern for the Nebraska Department of Transportation (NDOT). Recognizing this challenge, recent and ongoing research initiatives at NDOT, including projects SPR-FY22(001)1 and SPR-P1 (19)
M0832, as well as ongoing studies at NDOT Materials & Research (M&R), have identified promising strategies to mitigate this issue. These strategies include internal curing, reduction in cementitious material content, and the use of innovative admixtures (e.g., E5® Internal Cure admixture), all aimed at reducing shrinkage-related cracking in bridge decks. The previous projects exemplifies a successful approach for reducing free and restrained shrinkage strains in concrete bridge decks by reducing cementitious material content by 50, 100, and 150 lbs per cubic yard and optimizing aggregate gradation. This approach is expected to significantly lower the likelihood of shrinkage cracking in concrete bridge decks. Despite the progress in reducing concrete shrinkage, there remains a gap in understanding regarding the feasibility of shortened curing durations when using lower-shrinkage mixtures.
]]></description>
      <pubDate>Tue, 04 Jun 2024 12:04:49 GMT</pubDate>
      <guid>https://trid.trb.org/View/2387169</guid>
    </item>
    <item>
      <title>Impact of cement content in cement bound materials on the reflection cracking performance of asphalt pavements</title>
      <link>https://trid.trb.org/View/2378408</link>
      <description><![CDATA[This study investigates the impact of cement contents in cement bound material (CBM) on asphalt pavement reflection cracking, considering two levels: 4.5 % (CBM1) and 5.4 % (CBM2). Mechanical properties of CBMs, including elastic modulus, rupture modulus, and thermal expansion, were evaluated. Simultaneously, properties of asphalt pavement layers (wearing course and base course) underwent assessment through dynamic modulus, flow number, and overlay tests. Resilient modulus tests were conducted for subbase and subgrade layers. Laboratory test outcomes served as inputs for a AASHTOWare Pavement ME Design program. The results indicated that despite CBM2's higher elastic modulus and rupture modulus, CBM1 outperformed in pavement design. Based on the outcomes from pavement design program CBM1 exhibited lower total transverse cracking (400.19 m/km) compared to CBM2 (403.38 m/km) after 6 years of service. The higher cement content in CBM2 was identified as a potential contributor to increased cracking, attributed to shrinkage during cement hydration process. Moreover, the higher cement content showed a higher coefficient of thermal expansion (CTE), where CBM1 displayed a CTE of 70 µm/°C, while CBM2 material had a CTE of 40 µm/°C. These findings emphasize the intricate relationship between cement content in CBM and pavement performance, crucial for effective design considerations.]]></description>
      <pubDate>Mon, 13 May 2024 16:32:08 GMT</pubDate>
      <guid>https://trid.trb.org/View/2378408</guid>
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