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    <title>Transport Research International Documentation (TRID)</title>
    <link>https://trid.trb.org/</link>
    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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    <language>en-us</language>
    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
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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>Experimental measurements for ship motion responses coupling with fluidized washed kaolin slurry flow under wave actions</title>
      <link>https://trid.trb.org/View/2588034</link>
      <description><![CDATA[Experimental measurements are carried out for ship motion responses coupling with fluidized washed kaolin slurry flow. In the laboratory test, the washed kaolin slurry flow in tanks keeps on suspended states under wave actions. Coupling actions of fluidized washed kaolin slurry flow can generate the significant effect on roll motion responses. The typical anti-rolling behavior can be observed in beam sea, where the variation of roll motion amplitudes with incident periods shows the two-peak characteristics in such cases. With the increase of water contents, the variation tendency of coupling ship roll response deviates more from the results of empty ship. The increased filling depths can increased and decreased the peak values of roll amplitudes around the long-period and short-period ranges, respectively. The influence of fluidized washed kaolin slurry flow on sway motion responses are non-negligible at short-period range; while it is insignificant on heave motion responses. The motivation of this work is providing an experimental verification of the coupling effect between fluidized kaolin slurry and ship motion.]]></description>
      <pubDate>Mon, 27 Apr 2026 15:01:22 GMT</pubDate>
      <guid>https://trid.trb.org/View/2588034</guid>
    </item>
    <item>
      <title>A reliable approach for classifying metakaolin content of high-Performance concrete via machine learning algorithm</title>
      <link>https://trid.trb.org/View/2643531</link>
      <description><![CDATA[Cement production is energy-intensive and emits significant CO₂, making sustainable alternatives essential. Pozzolanic materials, such as fly ash, silica fume, and metakaolin, can partially replace cement, enhancing strength and durability while reducing costs and environmental impact. Metakaolin, derived from calcined kaolin clay, has gained interest in concrete applications. This study introduces a classification method for High-Performance Concrete based on metakaolin-to-cement ratios: Free (0%), Low (0%–20%), and High (20%–50%). Three tree-based classifiers (Decision Tree, Random Forest, and Stochastic Forest) were trained on 80% of 241 samples. Additionally, hybrid models were developed by fine-tuning hyperparameters using Swarm Magnetic, Sea-horse, and Exponential distribution optimizers. Classification performance was evaluated using various metrics, comparative visual plots, and Fourier Amplitude Sensitivity Tests. The Random Forest model optimized with the Swarm Magnetic Optimizer achieved the highest accuracy (95.8%), precision (97.9%), and F1-score (96.5%) across training, validation, and testing phases. These findings highlight the effectiveness of machine learning in optimizing concrete mixture designs and improving classification accuracy.]]></description>
      <pubDate>Mon, 02 Feb 2026 16:31:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/2643531</guid>
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    <item>
      <title>Geotechnical and microscopic behavior of the artificially structured clay induced by metakaolin-based geopolymer</title>
      <link>https://trid.trb.org/View/2618056</link>
      <description><![CDATA[The skeleton structure plays a dominant role in controlling the geotechnical properties of clay. To comprehensively reveal and evaluate this effect, this study proposes a novel artificially structured clay by using the metakaolin-based geopolymer, and systematically investigates its geotechnical and microscopic characteristics. A macrostructure coefficient M is introduced to quantitatively evaluate the skeleton structure behavior of this novel clay. In addition, a detailed comparison is conducted between the proposed structured clay and conventional artificially cement structured clay. The results indicate that the stress–strain relationships of metakaolin-based geopolymer structured clays exhibit typical strain-softening characteristics, and that a higher metakaolin-based geopolymer content leads to a stronger macrostructural response, characterized by a more distinct strain-softening relationship and a larger coefficient M. From the microstructural perspective, the metakaolin-based geopolymer structured clays show well-developed cementation and pronounced particle aggregation, confirming that the metakaolin-based geopolymer effectively promotes the formation of a stable skeleton structure. Compared with conventional cement-structured clays, the metakaolin-based geopolymer structured clays exhibit a more distinct skeleton structure, manifested by stronger strain-softening behavior and enhanced macrostructural characteristics. The findings of this study provide a novel and effective approach for investigating the skeleton structure properties of clay, thereby contributing to more accurate design and evaluation in geotechnical engineering applications.]]></description>
      <pubDate>Mon, 29 Dec 2025 09:34:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/2618056</guid>
    </item>
    <item>
      <title>Elucidating the effects of metakaolin-based geopolymer filler on the performance of styrene-butadiene-styrene modified asphalt: Microstructural insights and mechanistic analysis</title>
      <link>https://trid.trb.org/View/2563337</link>
      <description><![CDATA[This study aims to elucidate the effects of metakaolin-based geopolymer (Mk-Geo) filler on the performance of styrene-butadiene-styrene (SBS) modified asphalt and its underlying mechanisms. Mk-Geo asphalt mastics with varying filler-asphalt ratios (F/A = 0.2～1.4) were prepared, and their microstructural properties and physicochemical interactions were characterized using Fourier-transform infrared spectroscopy, thermogravimetric analysis, Brunauer-Emmett-Teller surface area analysis, and X-ray diffraction. The results revealed that Mk-Geo exhibits a multilayer mesoporous plate-like structure, which significantly influences its interaction with asphalt. Dynamic shear rheometer tests demonstrated that Mk-Geo enhances the high-temperature deformation resistance (indicated by an increase in the rutting factor G*/sinδ) and permanent deformation resistance, while also reducing temperature sensitivity. At F/A = 0.8, Mk-Geo promotes SBS phase swelling through surface adsorption, thereby improving the integrity of the three-dimensional network structure. As the F/A increases, the adsorption capacity of asphalt by the mesoporous structure increases, with a characteristic absorption peak of CaCO3 crystalline phase appearing at F/A = 1.4. However, High F/A negatively affects the fatigue performance of asphalt mastic, and premature fatigue damage occurs within the asphalt mastic at high strain levels and high F/A, leading to a reduction in fatigue life. In summary, the Mk-Geo can be applied not only as an adsorbent or modifier in asphalt materials, but also as a filler in asphalt mixtures, and the optimal F/A of 1.2 was obtained by ANOVA and statistical analysis. These findings provide a theoretical foundation for the functional application of geopolymers in asphalt pavement engineering.]]></description>
      <pubDate>Wed, 23 Jul 2025 09:14:31 GMT</pubDate>
      <guid>https://trid.trb.org/View/2563337</guid>
    </item>
    <item>
      <title>Mechanical properties of metakaolin and granulated blast-furnace slag-based roller-compacted geopolymer concrete containing 100% reclaimed asphalt pavement: Optimization and prediction via response surface methodology</title>
      <link>https://trid.trb.org/View/2528928</link>
      <description><![CDATA[The growing volume of Reclaimed Asphalt Pavement (RAP) waste, combined with the environmental impact of high cement production, highlights the urgent need for sustainable solutions. Alternative binders and efficient waste utilization offer promising ways to address these challenges. Unlike traditional concrete, which relies on supplementary cementing materials (SCM) to enhance strength, geopolymer concrete uses aluminosilicate sources (AS) to drive the geopolymerization process. This study explores the mechanical properties of roller-compacted geopolymer concrete (RCGC), focusing on the role of metakaolin (MK), both with and without granulated blast furnace slag (GBFS) as an additive AS. Hydrated lime (HL) was chosen as an alkali activator due to its affordability, availability, and its known effect on accelerating the setting process in geopolymer mixtures. The research examines how variations in sodium hydroxide molarity, HL content, and GBFS ratio influence the strength of RCGC. The results showed that increasing HL content had a negative impact on the mechanical properties, while higher concentrations of GBFS and sodium hydroxide (SH) significantly improved compressive, tensile, and flexural strengths. The optimal mix design, identified using response surface methodology (RSM) with a score of 0.96, consisted of 10M SH, no HL, and 40% GBFS, achieving a maximum 28-day compressive strength of 15.9MPa. Distinct failure modes were observed: MK-based RCGC exhibited mortar failure, while mixes containing 100% GBFS showed aggregate failure, indicating better structural integrity. These findings suggest that RCGC can serve as a sustainable and practical solution for low-volume road applications, offering both enhanced performance and environmental benefits.]]></description>
      <pubDate>Thu, 01 May 2025 09:37:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/2528928</guid>
    </item>
    <item>
      <title>Rheology and Aging Resistance of Asphalt Modified with Calcined Kaolin</title>
      <link>https://trid.trb.org/View/2480296</link>
      <description><![CDATA[This study aimed to explore the potential of calcined kaolin (CK) as an asphalt modifier. CK at 5%, 10%, 15%, and 20% by asphalt weight was blended in asphalt binder at a high temperature, followed by aging treatments using a rolling thin film oven (RTFOT) and a pressure aging vessel (PAV). Changes in rutting, fatigue, temperature susceptibility, and aging resistance of the modified asphalt were tracked. The composition and structure of CK were analyzed using X-ray diffraction (XRD) and backscattered electron imaging-particle size (BSD-PS). Rheological studies of the modified asphalt were conducted using rotational viscosity, frequency sweep, multiple stress creep recovery (MSCR), and linear amplitude sweep (LAS) tests. The effects of CK on bitumen after thermo-oxidative aging performance decay were evaluated using aging indexes of physical indicators, complex modulus, and the phase angle. With the addition of CK, significant enhancement to stiffness was observed in the low- to mid-frequency range in the asphalt master curves, indicating that the impact of CK was mainly within the medium- to high-temperature range. The MSCR test results showed that the Jnr₃.₂ value for CK-modified asphalt accounts for 62% to 71% of virgin asphalt, indicating high rutting performance. The Cole–Cole diagram revealed different degrees of slope deviation toward the storage modulus axis for the storage and loss modulus curves after adding CK, suggesting an improvement in the asphalt’s elastic properties. The CK asphalt binder exhibited higher R-values (152% to 181% of the virgin asphalt for R₀.₁ in the MSCR test) and fatigue cycle times (118% to 155% of the virgin asphalt for Nf in the LAS test) than those of virgin asphalt. Aging indexes and the Fourier-transform infrared spectroscopy (FTIR) test results indicated that CK can delay oxygen diffusion and the volatilization of lighter components. In conclusion, the results demonstrate that CK can effectively serve as a modifier to improve the mechanical and aging properties of asphalt binders.]]></description>
      <pubDate>Wed, 26 Feb 2025 09:10:34 GMT</pubDate>
      <guid>https://trid.trb.org/View/2480296</guid>
    </item>
    <item>
      <title>Engineering Properties of Treated Clay by Kaolin–Rice Husk Ash Geopolymer Activated with Sodium Hydroxide Solution</title>
      <link>https://trid.trb.org/View/2437715</link>
      <description><![CDATA[Thailand’s highway development project and expansion of the main road are currently being built or planned. The development of stabilizing techniques in soils with various agents has been adopted since the early days due to the insufficient availability of local materials and their unsatisfactory engineering properties. Rice husk ash’s (RHA) partial replacement of geopolymers in road-based applications received less attention. This study examines the engineering properties of clay (C) treated by kaolin–rice husk ash geopolymer (K-RHAGP). The ordinary clay is activated by sodium hydroxide solution. The appropriate proportion of kaolin:rice husk ash (K:RHA) of 70:30 stimulated by a sodium hydroxide solution of 8 molars exhibits the highest unconfined compressive strength (qₙ). Clay is treated by kaolin–rice husk ash geopolymer (K-RHAGP) with various ratios of C:K-RHAGP by weights of 90:10, 80:20, 70:30, 60:40, and 50:50. The results showed that the optimal C:K-RHAGP proportion of treated clay is 70:30, which yielded the highest qₙ at 7 days under curing temperatures of 70 °C and 50 °C, resulting in values of 9352 and 4557 kN/m², respectively. The highest split tensile strength under 70 °C and 50 °C curing temperatures was 1182 and 576 kN/m², respectively. The relationship between the modulus of elasticity at 50% strength, E₅₀, and qₙ is expressed as E₅₀ = 4.531qₙ. After wet and dry processes, the samples with the C:K-RHAGP ratio of 70:30 exhibit the highest strengths of 2445.89, 1670.55, and 1218.68 kN/m² for 3, 9, and 12 wet–dry cycles corresponding to the lowest weight loss. The C:K-RHAGP weight loss of 70:30 in cycles 1 to 12 was 1.5 to 7.2%. The authors believe that the proposed K-RHAGP stabilization could be used as an effective replacement for cement-based soil stabilization in road-based construction.]]></description>
      <pubDate>Tue, 15 Oct 2024 16:14:47 GMT</pubDate>
      <guid>https://trid.trb.org/View/2437715</guid>
    </item>
    <item>
      <title>Effect of kaolin and sepiolite on fume emissions of rubber modified asphalt</title>
      <link>https://trid.trb.org/View/2335888</link>
      <description><![CDATA[During the process of high temperature mixing, crumb rubber modified asphalt will release fumes, causing potential threat to human health and the environment. To reduce the harmful fumes released during the production of rubber modified asphalt (RA), a high-performance and environmentally friendly rubber modified asphalt (K/S-RA) was prepared by adding kaolin and sepiolite as composite modifier. The improvement of the composite modifier on road performance and its inhibitory effect on the fume emissions of rubber modified asphalt were studied, and the fume suppression mechanism and synergistic effect of the two modifiers were discussed. The results showed that the kaolin and sepiolite composite increased the rutting factor and fatigue factor of rubber modified asphalt, thus improving anti-deformation ability and decreasing it fatigue resistance. The results of Gas chromatography-mass spectrometry (GC-MS) showed that compared with conventional rubber modified asphalt, the concentration of VOCs in K/S-RA was reduced by 42.26%, and the H₂S was reduced by 65.28%. Thermogravimetric Analysis and Differential Scanning Calorimetry (TG-DSC) and Brunner-Emmet-Teller (BET) results showed that kaolin and sepiolite had a synergistic effect of heat insulation and adsorption on the fume suppression of rubber modified asphalt.]]></description>
      <pubDate>Fri, 15 Mar 2024 16:35:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2335888</guid>
    </item>
    <item>
      <title>Incorporating metakaolin in paving blocks: effect on physical and mechanical properties</title>
      <link>https://trid.trb.org/View/2310570</link>
      <description><![CDATA[This article investigated the influence of the incorporation of metakaolin in paving blocks. Two methods of incorporation were conducted in two factories. The first method consisted of addition with 10, 15, 20, 25, and 30% metakaolin in relation to the amount of cement, and the second one analysed the partial replacement of cement in the contents of 4, 8, and 10%. The results showed that in mixtures with replacement, the metakaolin did not show improvements in all properties. In contrast, in cases with addition, the compressive strength improved, and absorption was reduced. In both methods, the abrasion resistance did not change with the incorporation of metakaolin. Finally, the addition of 10% proved to be sufficient for application in paving blocks.]]></description>
      <pubDate>Mon, 26 Feb 2024 11:53:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/2310570</guid>
    </item>
    <item>
      <title>Early performance and bonding mechanism of metakaolin (MK)- ground granulated blast furnace slag (GGBS) based geopolymer road repair mortar</title>
      <link>https://trid.trb.org/View/2310605</link>
      <description><![CDATA[Metakaolin (MK) and ground granulated blast furnace slag (GGBS) based geopolymers have been utilised as materials for concrete road repair. However, their early-stage performance and bonding mechanism as rapid repairs are not well understood. This research investigated the workability, early strength development and bonding mechanism of geopolymer repair mortars with different GGBS contents. The reaction kinetics and reaction products of the geopolymer repairs were analyzed through reaction heat evolution and FTIR, and the microstructure of the bonding interface was examined using BSE-EDS. Results showed that geopolymer repair mortars with higher GGBS content exhibited shorter setting times, higher flowability, and higher compressive strength. Geopolymers demonstrated a one-dimensional rod-shaped nucleation pattern during hardening, and the crystallization rate decreased with GGBS addition. GGBS increased the formation of C-A-S-H gels and accelerated the geopolymerization process. However, excessive GGBS reduced bond strength due to the introduction of microcracks. A GGBS content of 60 wt.% is recommended in this investigation. The study also revealed that the cement substrate could absorb alkali activator, leading to the formation of high-Ca gels and strengthening the interface.]]></description>
      <pubDate>Mon, 12 Feb 2024 10:31:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/2310605</guid>
    </item>
    <item>
      <title>Experimental Study and Prediction of Water Retention Curves of an Unsaturated Kaolin</title>
      <link>https://trid.trb.org/View/2334635</link>
      <description><![CDATA[In this research, soil water retention curves (SWRCs) of compacted kaolin at different dry unit weights were measured using experimental techniques of filter paper and pressure plate. The results show that the water retention behavior of kaolin is independent of the type of measurement method, and the initial dry unit weight of the sample is the most significant factor governing the SWRCs. In other words, the preparation of the samples with different water contents in the filter paper method and the possible resulting changes in the soil fabric do not substantially affect the water retention behavior of kaolin. An existing model was adopted for predicting the behavior of these curves under different dry unit weights. Investigation of the results indicates that the performance of this model is suitable for predicting the SWRCs of samples with nearly identical initial dry unit weights. In contrast, it is inappropriate for samples with wide ranges of dry unit weights. Finally, an alternative method was presented in selecting the model parameters to modify the model predictions of SWRCs. Furthermore, since the behavior of SWRCs is similar to the curves of the low-pass Butterworth filter, this function was used to simulate the SWRCs and gave good agreement with the experimental results.]]></description>
      <pubDate>Fri, 09 Feb 2024 13:42:06 GMT</pubDate>
      <guid>https://trid.trb.org/View/2334635</guid>
    </item>
    <item>
      <title>Design optimization and performance evaluation of metakaolin-based geopolymer filled porous (semi-flexible) asphalt mixture</title>
      <link>https://trid.trb.org/View/2263018</link>
      <description><![CDATA[This study was conducted to enhance the mixture design proportions and performance of metakaolin based geopolymer (MKG) filled porous asphalt concrete (MKGAC) mixture. The optimum dosage contents of various admixtures, namely fly ash, fine sand, expansion agent, and coupling agent, were determined based on the laboratory evaluation of the mechanical, shrinkage, and fluidity properties of the modified MKG. Additionally, scanning electron microscope (SEM), energy spectra, X-ray diffraction (XRD), and surface free energy measurements were also conducted to characterize the morphological structure and interfacial bonding of the basic (unmodified) and modified MKGAC. In the study, the solid content of the basic MKG was varied within a range of 26%–32%, with 30% determined as the optimum content for maximizing workability and performance characteristics, namely fluidity, shrinkage resistance, low-temperature cracking resistance, moisture resistance, high-temperature stability, and fatigue-crack resistance potential. Based on the high-temperature stability, fatigue, low-temperature cracking, and moisture resistance evaluations, 30% fly ash, 40% fine sand, 6% HCSA expansive agent, and 1.25% KH550 coupling agent were recommended as the optimum admixture contents for modifying and maximizing the performance of MKGAC. The SEM, energy spectra, and XRD analyses, on the other hand, showed that the microstructure and morphological compositions of the geopolymer (MKG) were uniformly consistent after modification with the admixtures. Lastly, it was also quantitatively observed that the interfacial energy between the geopolymer and asphalt-binder matrix increased after adding the admixtures, indicating an enhancement in the adhesive bond strength between the geopolymer (MKG) and the asphalt-binder matrix.]]></description>
      <pubDate>Tue, 07 Nov 2023 16:01:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/2263018</guid>
    </item>
    <item>
      <title>Preparation and rheological performance analysis of volcanic ash and metakaolin based geopolymer grouting materials</title>
      <link>https://trid.trb.org/View/2167175</link>
      <description><![CDATA[This study investigated the possibility of using volcanic ash and metakaolin (MK) to prepare road grouting materials. The effects of different contents of MK and water glass(WG) on the mechanical properties, setting time and rheological properties of the materials were investigated separately. The materials science testing methods were also used to observe the reaction mechanism of the geopolymer products. The test results showed that the compressive strength increased with the content of MK and SS. The average flow curve of geopolymer grouts fitted the Bingham model. The multilayer lamellar microstructure of MK increases the rheological parameters of the pastes. While the WG suspends VA and MK particles, which reduces the rheological parameters of the pastes. It can be concluded from the results of microscopic experiments that the MK reduces side reactions as well as sodium by-products, while WG produces more silica-aluminate filling the voids which enhances the compressive strength.]]></description>
      <pubDate>Sun, 15 Oct 2023 17:36:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/2167175</guid>
    </item>
    <item>
      <title>Effects of Liquid Polymers on the Strength and Freezing-Thawing Properties of Bentonite and Kaolin Clays: A Comparative Study for Cold Climates</title>
      <link>https://trid.trb.org/View/2201218</link>
      <description><![CDATA[Clay soils can exhibit swelling and settlement behaviour when interacted with water. The clays located in road infrastructure can damage the road pavement and cause cracks because of swelling and/or settlement of clays. The freezing-thawing processes of clay soils can increase the damages of pavement. Additionally, the strength losses can occur. Weak soils can be improved using various soil improvement techniques with or without additives. In this study, liquid polymers (polyurethane, epoxy resin, and styrene acrylic) were combined with clays in various amounts (5 wt.%, 10 wt.%, 15 wt.%, and 20 wt.%) to improve the strength and investigate the freezing-thawing behaviour of high-plasticity bentonite and low-plasticity kaolin clay. Unconfined compression tests and freezing-thawing cycles were performed on the samples with additives that were cured for 1 and 7 days. As a result, it was observed that polyurethane, epoxy resin, and styrene acrylic additives had positive effects on both the unconfined compressive and the post freezing-thawing unconfined compressive strengths of low and high plasticity clays in cold climates.]]></description>
      <pubDate>Mon, 24 Jul 2023 16:37:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/2201218</guid>
    </item>
    <item>
      <title>Laboratory study of metakaolin and microsilica effect on the performance of high-strength concrete containing Forta fibers</title>
      <link>https://trid.trb.org/View/2205266</link>
      <description><![CDATA[The present study aims to produce high-strength fiber concrete containing microsilica and metakaolin. Eight concrete mixing samples have been defined. The samples include the control concrete with ordinary Portland cement, replacing 10 percent of the weight of cement with microsilica. The amount of microsilica was kept constant in the next six designs. Three samples with the addition of Forta fibers at the rate of 0.2, 0.5, and 0.8 percent. Finally three samples with 0.5% Forta fibers and 8, 10 and 12% metakaolin were subjected to compressive, tensile and elastic modulus tests at the ages of 7 and 28 days. The addition of Forta fibers and the replacement of microsilica and metakaolin in concrete reduced the slump of concrete up to 5 cm. The highest compressive strength, tensile strength and elastic modulus at the age of 28 days of design 8 (concrete containing 10% microsilica, 0.5% Forte fibers and 12% metakaolin) are respectively equal to 73.6 MPa, 5.55 MPa and 37.49 MPa with The increase was 19.43%, 32.77% and 15.21% compared to control concrete without pozzolan and additives. Also, the relationship between compressive and tensile strength were presented. In total, all samples containing microsilica and fibers had a favorable effect on the resistance properties of concrete compared to the control design. The constant concern of bridge engineers, especially concrete bridges, is the production of concrete with high-strength and very low permeability in the face of their surroundings. Therefore, the result of this research can be a significant contribution to improving the quality of concrete used in bridge constructions.]]></description>
      <pubDate>Fri, 21 Jul 2023 09:18:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/2205266</guid>
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