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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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    <item>
      <title>Sustainable Stabilization of Expansive Clays with Waste Glass and Polymer for Improved Pavement Subgrades</title>
      <link>https://trid.trb.org/View/2705373</link>
      <description><![CDATA[Expansive clays present significant geotechnical challenges, often damaging structures and road networks, and requiring reliable stabilization techniques. This study investigates the combined use of waste glass and vinyl acetate ethylene (VAE) polymer to stabilize two types of expansive clays (i.e., slightly and highly expansive), offering a potential solution that addresses both environmental and engineering concerns. Fixed glass contents of 10% and 15% were introduced to the highly expansive and slightly expansive clay, respectively, alongside varying polymer contents of 0, 1, 1.5, and 2%. The stabilized clays were subsequently evaluated through a comprehensive series of physicochemical, microstructural, and mechanical tests, including X-ray microCT, X-ray diffraction, X-ray fluorescence, thermogravimetric analysis, standard compaction, unconfined compression strength (UCS), California bearing ratio (CBR), resilient modulus, swelling-shrinkage testing, and soil-water retention curve. The results revealed that treatment with waste glass and an optimum polymer dosage of 1.5% significantly enhanced the UCS, CBR, and resilient modulus for highly expansive clay, increasing from 1.18 to 1.75 MPa, 20% to 31.7%, and 156.05 to 232.91 MPa, respectively. Similarly, for slightly expansive clay, UCS increased from 1.10 to 1.31 MPa, CBR from 18.9% to 30.20%, and resilient modulus from 175.66 to 236.92 MPa. A reduction in the mechanical strength was observed upon increasing the polymer content beyond 1.5%, although a polymer dosage of 2% proved most effective in mitigating swell-shrink behavior.]]></description>
      <pubDate>Fri, 28 Aug 2026 08:34:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/2705373</guid>
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    <item>
      <title>Strength Enhancement of Expansive Clay Using fly Ash-bagasse ash Binder and Basalt Fiber Reinforcement</title>
      <link>https://trid.trb.org/View/2697816</link>
      <description><![CDATA[This study investigates the synergistic effects of binder containing fly ash-bagasse ash and reinforced with basalt fiber (BF) for stabilizing of black cotton (BC) soil. The geotechnical characteristics of BC soil were evaluated. With the addition of the binder and BF, the MDD was increased from 1545 kg/m³ to 1760 kg/m³, while the OMC decreased from 24.5% to 20.10%. The Unconfined compressive strength of BC soil increased from 144.15 kPa to 424.20 kPa after binder treatment and further increased to 976.17 kPa when reinforced with 1.5% BF after 28 days of curing. The 28-day cured CBR of the treated soil improved from 2.65% to 13.62%. Similarly, the split tensile strength of treated soil increased from 48 kPa to 855 kPa. Morphological analysis using XRD and SEM-EDS was performed on the optimally binder-treated reinforced samples. The analysis confirmed improved particle bonding attributed to pozzolanic reactions forming cementitious compounds such as C-S-H, C-A-H, along with fiber reinforcement. The effect of binder on reinforced soil increases the interfacial bond strength between the soil and BF. These findings highlight that the incorporation of the optimized binder with BF provides a sustainable and effective approach for enhancing soil strength.]]></description>
      <pubDate>Tue, 23 Jun 2026 13:51:05 GMT</pubDate>
      <guid>https://trid.trb.org/View/2697816</guid>
    </item>
    <item>
      <title>Assessment of Geopolymer Synthesis Parameters for Strength of Stabilized Fat Clay Using Statistical and Machine Learning Techniques</title>
      <link>https://trid.trb.org/View/2704073</link>
      <description><![CDATA[Calcium-based chemical stabilizers are traditionally used for the stabilization of weak subgrade soils. However, these traditional stabilizers incur significant environmental costs which make them less desirable. As a result, alternative materials based on recycled waste and industrial byproducts are becoming popular. Geopolymers (GP) are a new addition to this list that are gaining traction because of their environmental benefits. GPs improve the soil by precipitation of a polymer gel as a result of mixing an alkaline activator (activator) with an aluminosilicate source (precursor). The effectiveness of GP and the improvement in engineering performance of GP-stabilized soils is contingent on sound GP synthesis parameters. This study investigates the effectiveness of GP-based treatments in improving weak soil and evaluates the significance of various parameters in contributing to the efficacy of GP treatment. As a result, a group of eight GP mixes was designed with a range of values for controlling parameters namely water/solid, activator/precursor, Si/Al and cation/Al ratios. A fat clay was treated by the application of these GP mixes at a dosage of 10% by dry weight. Improvements in mechanical strength were evaluated through unconfined compression strength testing. This was followed by statistical inference on laboratory strength data using analysis of variance (ANOVA) and post hoc tests. Ultimately, parameter importance was quantified by the random forest (RF) regression model. The results indicated that GP-based treatments enhanced the strength of untreated soil. Additionally, GP with higher aluminosilicate content and sufficient activator performed better. Overall, this study provides insight into the relative contribution of various GP synthesis parameters to the performance of GP-stabilized subgrade soils.]]></description>
      <pubDate>Thu, 21 May 2026 09:09:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/2704073</guid>
    </item>
    <item>
      <title>Laboratory and field assessment of gypsum-modified aluminosilicate blends for expansive clay stabilization</title>
      <link>https://trid.trb.org/View/2647965</link>
      <description><![CDATA[Expansive clays pose significant challenges in civil engineering due to their high shrink–swell potential, which can compromise stability and cause structural damage. This study adopts a phased approach to develop effective stabilizer blends by integrating gypsum into industrial by-products, such as fly ash and slag, to enhance the durability of smectite-rich clay. In the first phase, gypsum-free blends were formulated to investigate the combined effects of additives and determine the optimal stabilizer content. The best-performing mix was then tested in a field implementation phase to validate its performance under real-world conditions. In the later phase, gypsum was incorporated and evaluated under wetting–drying (W–D) cycles to simulate environmental moisture fluctuations. The gypsum content was limited to avoid excessive sulfate reactions, particularly ettringite formation. An integrated framework, including strength testing, chemical assessment, and mineralogical analysis, was applied to unmodified, gypsum-modified, and gypsum-modified samples subjected to W–D cycling. Chemical treatment significantly improved strength, increasing the unconfined compressive strength (0.31 MPa) of untreated soil by about 6–8 times, with Class C fly ash and slag providing the best performance. The gypsum-modified blend retained ∼54 % of its initial strength after five W–D cycles, demonstrating improved resistance to moisture-induced deterioration. Mineralogical analyses indicated transformations such as smectite modification, ettringite formation, and calcite precipitation. These findings underscore gypsum’s role in enhancing the performance of expansive soils with moisture fluctuations and contribute to advancing stabilization strategies for resilient transportation infrastructure.]]></description>
      <pubDate>Tue, 24 Mar 2026 09:09:08 GMT</pubDate>
      <guid>https://trid.trb.org/View/2647965</guid>
    </item>
    <item>
      <title>Insights into the Influence of Environmental Stressors on Expansive Subgrades Stabilized with Different Calcium-Based Stabilizers for Resilient Transportation Infrastructure</title>
      <link>https://trid.trb.org/View/2681411</link>
      <description><![CDATA[Although chemical stabilization is well practiced in dealing with expansive soils, these soils’ endurance to extreme weather events is still questionable because of potential alterations in microstructure and degradation of stabilization products. This study, therefore, investigates how moisture and temperature variations affect the structure and engineering behavior of chemically stabilized expansive clay. A series of unconfined compressive strength tests were conducted before and after freezing–thawing (FT) and wetting–drying (WD) conditioning on high-plasticity clay stabilized with cement or hydrated lime, with lime sludge as a co-additive. Cement treatment resulted in a higher initial strength (3.1 MPa) compared with hydrated lime treatment (1.3 MPa), primarily as a result of the rapid formation of binding gels through cement hydration. However, environmental conditioning and post-conditioning testing protocols significantly affected the void ratio and saturation levels of specimens, yielding different strength values for both cement and lime treatments. Cement-treated specimens experienced a strength reduction under both FT and WD conditions, with a more pronounced decrease after WD. However, lime-treated specimens exhibited an interesting trend of getting weakened after FT but becoming stronger after WD. These differences are mainly attributed to variations in the evolution of void ratio and saturation levels during the respective conditioning and post-conditioning phases. To further confirm these links, data from the experiments was fed into a random forest regression model to identify key factors influencing the engineering performance. Sensitivity analysis showed the degree of saturation (0.53) to be marginally more influential than the void ratio (0.47) in determining the strength, aligning with the experimental findings.]]></description>
      <pubDate>Fri, 20 Mar 2026 08:38:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/2681411</guid>
    </item>
    <item>
      <title>Micro-to-Macro Insights into Durability of Stabilized Soils Exposed to Wetting-Drying Cycles  </title>
      <link>https://trid.trb.org/View/2646953</link>
      <description><![CDATA[Roads built on problematic soils like expansive and soft clays often fail prematurely due to issues like heaving, cracking, and rutting. Low-strength, high-compressibility, and moisture sensitivity of these soils, primarily driven by the reactive nature of clay minerals, are the underlying causes for this. Stabilizing such problematic soils with cementitious binders is a common practice. Soils are often subjected to severe Wetting-Drying (W-D) cycles due to extreme weather events like flooding during monsoons and heat waves during summers and the long-term durability of stabilized soils under these stresses remains a critical concern. Often, failure in the system due to these W-D cycles is progressive in nature, starting from the generation of micro-cracks that eventually propagate into fully developed fractures within the soil mass. Also, the pore structure and pore connectivity alter significantly during this process, and manifest into the overall strength and performance deterioration. The evolution of the pore network, number of cracks, and their morphological features, like the length, width, and connectivity, are extremely important to understand the longevity and durability of stabilized soils to ensure safety of the transportation infrastructure. With this objective, this project aims to investigate the micro-to-macro scale damage progression in stabilized soils subjected to the W-D durability cycles. The study will be conducted on soft soil (low-plasticity clay) with two different stabilizers, namely Portland limestone cement and lime. Modification to the workability and strength characteristics of the stabilized soils will be quantified through laboratory tests, including Atterberg limits, Proctor compaction, and Unconfined Compressive Strength (UCS) tests, and the optimum dosages of the stabilizers will be determined. Durability assessment of the stabilized soils with optimum dosages will be evaluated for 0, 2, 4, 8, and 12 W-D cycles following the ASTM D559 & AASHTO T135 testing protocols with different specimen sizes. Mass loss, volumetric strain, and UCS values post-durability cycles will be recorded from different specimen sizes and compared to evaluate the effects of specimen size on the durability evaluation. This data will be beneficial for simplifying and advancing the durability testing protocols. Additionally, advanced X-ray micro-Computed Tomography (μCT) will be used to visualize and quantify internal microstructural changes, such as pore connectivity and crack morphology evolution, in miniature soil specimens. Image analysis algorithms may be developed for the robust and accurate quantification of the microstructure. Finally, correlations will be developed between the total porosity, number of cracks, crack length, crack width, and the UCS values of soil for various durability cycles. These correlations are expected to aid in the realistic prediction of the long-term performance of stabilized soils. Micro-perspectives and insights from this project will be crucial for developing more resistant and durabletransportation infrastructure in regions with problematic soils.]]></description>
      <pubDate>Mon, 12 Jan 2026 15:59:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/2646953</guid>
    </item>
    <item>
      <title>Valorization of waste tire textile fibers for durability enhancement of expansive clay stabilized with calcium carbide residue and water treatment sludge</title>
      <link>https://trid.trb.org/View/2622299</link>
      <description><![CDATA[Chemical soil stabilization often leads to excessive brittleness and stiffness due to alterations in the soil’s composition, highlighting the necessity of reinforcement to enhance mechanical performance. This study evaluates the effect of waste tire textile fibers (WTTFs) as reinforcement in swelling soils stabilized with calcium carbide residue (CCR) and water treatment sludge (WTS) by examining their mechanical behavior and durability under freeze–thaw cycles (FTCs). Specimens were prepared using an optimal proportion of 25 % CCR and 10 % WTS as a partial replacement for CCR, along with varying WTTF contents of up to 2 %. Following curing periods of 7, 28, and 56 days, the samples were subjected to up to 12 FTCs. Their durability and strength were assessed through a series of tests and microstructural analyses. Findings revealed that incorporating WTTF significantly improved the ductility, compressive strength, tensile strength, stiffness, as well as failure strain of the treated samples. Specifically, at the optimum WTTF content of 1.5 %, the treated soil achieved a UCS of 9000 kPa, an ITS of 1370 kPa, and a UPV of 2500 m/s. Moreover, fiber inclusion enhanced freeze–thaw durability, markedly reducing strength loss over multiple cycles. At 1.5 % WTTF content, the average strength loss after 12 FTCs was limited to 16 %, compared to 58 % for the untreated soil and 33 % for optimally CCR-WTS-treated soil. Furthermore, WTTF reinforcement effectively controlled the swelling potential. Microstructural analysis revealed strong bonding between WTTF and cementitious gels, forming an integrated matrix that improved structural integrity under harsh climatic conditions.]]></description>
      <pubDate>Mon, 05 Jan 2026 09:52:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/2622299</guid>
    </item>
    <item>
      <title>Materials for PVR Short Course and Training</title>
      <link>https://trid.trb.org/View/2582268</link>
      <description><![CDATA[The materials for the Project 5-6048-03 short course and training include a presentation that goes over the basics of the Potential Vertical Rise (PVR) method (Appendix A). The presentation is based on the work compiled over the course of 5-6048-03. Notes are included in the presentation for the instructors based on the recommendations from the research team, providing guidance on the aspects that should be emphasized. Appendix B includes a guidance manual outlining the typical steps for calculation of the PVR. Finally, Appendix C includes the main changes to current standard, Tex-124-E, outlining the revised steps used to calculate PVR as well as notes on recommendations by the research team.]]></description>
      <pubDate>Sat, 08 Nov 2025 17:39:34 GMT</pubDate>
      <guid>https://trid.trb.org/View/2582268</guid>
    </item>
    <item>
      <title>Expert System Design Guide for Lower Classification Roads over High PI Clays</title>
      <link>https://trid.trb.org/View/2572366</link>
      <description><![CDATA[The focus of this report is the process with which an expert system was developed to improve the design procedures of low-volume roads over expansive clayey soils. The guide combines numerical and engineering analyses with heuristic information about the site to recommend best design and construction practices. Numerical analysis is performed to predict longitudinal cracking distress, which was reported by a district survey throughout Texas to be one of the most prevailing distresses. Other common distresses are studied. Traditional and new remediation methods are proposed to address the problem of premature failure of low-volume roads on high-PI clays. Finally cost and benefit analysis are added to the design guide framework to complete the computer program and to accomplish the objectives of this project.]]></description>
      <pubDate>Tue, 16 Sep 2025 12:00:44 GMT</pubDate>
      <guid>https://trid.trb.org/View/2572366</guid>
    </item>
    <item>
      <title>Impact of Moisture Variation on Strength and Deformation of Clays</title>
      <link>https://trid.trb.org/View/2572365</link>
      <description><![CDATA[This research project was focused on low-volume roads over expansive clayey soils in Texas. In spite of the over conservative pavement designs recommended and widely used in Texas for roads in high PI clay areas, these pavements often fail prematurely. It is imperative to improve the design and laboratory procedures to address expansive subsoil conditions and then design pavements accordingly to extend the life expectancy of these roads. The intent of this research project was to cultivate the vital features of strategies for improving low-volume flexible pavement design and thus improving the overall low-volume road performance. These include: 1) Identify the most significant soil parameters directly related to the performance of these types of roads; 2) Propose practical laboratory test methods and analyzing models to address the problem of premature failure of low-volume roads on high PI expansive subgrade; 3) Qualify and quantify current remediation procedures, climatic effects and road condition assessment (both successful and unsuccessful) used to mitigate the shrink-swell problems; and 4) Develop a user-friendly expert system design tool to guide the designers through the process for more realistic designs and rehabilitations. This document provides information about the first two items. Static compaction in one lift was found to be the most practical procedure. The variations in modulus and shrinkage/expansion strains with moisture under a number of different moisture conditioning procedures were evaluated. For each moisture conditioning process, models were developed to estimate the variations in the modulus and shrinkage/expansion strains with moisture. Finally the fit parameters of those models were correlated to the index properties of the clays so that they can be readily used in practice. The developed models in this research project were implemented in the assessment of the pavement performance in Research Report 5430-2.]]></description>
      <pubDate>Tue, 16 Sep 2025 12:00:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2572365</guid>
    </item>
    <item>
      <title>An Experimental Based Approach to Estimate the Overall Modulus/CBR of Geocomposite-Reinforced Subgrades and Use of the Austroads Design Chart</title>
      <link>https://trid.trb.org/View/2559560</link>
      <description><![CDATA[The soft subgrade imposes problems on geotechnical/pavement engineers when designing road pavements and construction platforms, as its modulus and bearing capacity do not meet the requirements to support the design load. The issues are more challenging when the soft subgrade consists of expansive clays that are widely spread in Queensland, Australia. The subgrade replacement, lime treatment, and a thicker granular cover over the subgrade are widely used to treat soft and expansive subgrades. However, these subgrade treatment methods impose numerous environmental and financial concerns as they use depleting natural resources producing dust and greenhouse gases. Therefore, the research on construction and demolition waste has suggested using recycled concrete aggregates (RCA) and recycled asphalt pavement (RAP) as natural gravel replacements, Further, ongoing research is investigating the use of waste such as fly ash, incinerated ash, and slug to treat the soft and expansive subgrades.]]></description>
      <pubDate>Thu, 21 Aug 2025 09:19:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/2559560</guid>
    </item>
    <item>
      <title>Pavement Roughness on Expansive Clays</title>
      <link>https://trid.trb.org/View/2561669</link>
      <description><![CDATA[The patterns of pavement roughness caused by expansive clays are due largely to the underlying patterns of cracks in the subgrade soil mass. The cracks will be closer together when the soil is more active and when the climatic wetting and drying cycles have greater influence. The cracking patterns in the soil and the consequent roughness patterns are not uniform but must be characterized as a spectrum of crack spacings and wavelengths with their corresponding amplitudes. Pavement roughness was measured by the GM Profilometer on 23 pavement sections in Texas. Two methods are used to obtain the amplitude versus wavelength spectra that characterize the roughness patterns: the Fast Fourier Transform (FFT) method and the "bump counter" direct method. The two spectra are not the same nor are they expected to be. The FFT method is adopted for characterizing the roughness patterns because of its greater consistency. However, a correspondence is found between the two spectra. As a matter of convenience, the spectra are plotted as amplitude versus frequency, which is the number of wavelengths per unit length. The graphs of amplitude versus frequency were fitted by a power law equation with two constants, c and n, which are found to be correlated with each other. Unique values of c and n characterize the roughness pattern of each pavement and these, in turn, are found to depend upon the composite flexural stiffness of the pavement, time, climatic measures, and several physico-chemical soil properties. Four soil properties are found to be necessary to predict the roughness spectra: (a) cation exchange capacity which is an indicator of the kind of mineral that is present, (b) percent clay which shows how much clay is present in the subgrade soil, (c) exchange sodium percentage which is partly an indication of the geological environment in which the clay was deposited and partly an indication of how erodable and dispersive the soil is, and (d) the plasticity index which is a measure of the moisture reactivity of the soil. The dominant wavelengths in each of the roughness patterns are determined together with cumulative distributions of wavelengths and amplitudes for each of the pavement sections studied. Probability density functions for wavelengths are developed from these data. A method for using these wavelength probabilities and the corresponding amplitude spectral equation is developed to calculate the amount of level-up material that must be placed on the pavement to achieve a smooth ride. A method of computing the amount of material that can be removed by heater-planing and milling operating is also shown. An equation for the loss of serviceability index with time is developed and several examples are presented showing how the serviceability loss depends upon soil and pavement properties. The equation for serviceability index loss constitutes a design equation for pavements on expansive soils.]]></description>
      <pubDate>Mon, 21 Jul 2025 16:19:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/2561669</guid>
    </item>
    <item>
      <title>Investigation of Swelling Clay Soils in Subgrades of SH 6 and SH 21</title>
      <link>https://trid.trb.org/View/2549176</link>
      <description><![CDATA[In the Bryan District, SH 6 and SH 21 are experiencing severe pavement distortion in several locations causing an exceptionally rough ride. Routine site investigation prior to construction did not reveal underlying soil conditions that could produce the kinds of pavement distresses that appeared relatively soon after pavement construction was completed. These 2 areas were investigated using innovative, state-of-the-art field and laboratory testing techniques to determine the origin(s) of the pavement distresses manifested at the surface and to determine what could be done to alleviate the existing pavement surface problems or what site investigation techniques should be employed in the future to circumvent the recurrence of these types of problems. Specific objectives of the research study were to conduct detailed site investigations using state-of-the-art techniques, analyze data to isolate cause(s) of the pavement distress, suggest alternatives to stabilize the swelling soils, recommend site investigation techniques to identify similar problem soil profiles in future construction sites, and develop treatments to stabilize such soils and, thus, minimize pavement distress. Findings indicated the swells were not caused by lime stabilization of sulfate bearing soils but were the result of surface water flowing through deep cracks or permeable soil layers to highly plastic expansive clays. Recommended remedial actions to reduce subsequent swelling and site investigation procedures to detect potential problems during the construction process are given.]]></description>
      <pubDate>Wed, 25 Jun 2025 14:47:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/2549176</guid>
    </item>
    <item>
      <title>Characterization of the Swelling Clay Parameter Used in the Pavement Design System</title>
      <link>https://trid.trb.org/View/2521862</link>
      <description><![CDATA[The purpose of this study was to quantify the swelling clay parameter used in the systems approach to pavement design. The quantification of the parameter was to be made using data from standard laboratory soils tests and actual concrete pavements. The pavement sections used in the research were chosen so that only the soil properties of the subgrade varied. To insure that the subgrade soils were different, statistical tests were performed. The quantification of the parameter involved three steps. First, the Present Serviceability Indexes were computed from the average slope variances of the pavement sections at various times. With the PSI versus time data, the swelling clay parameter was characterized using the Serviceability Loss Function. Using the calculated values for the swelling clay parameter and various soil properties, the parameter was quantified. The quantification was made using both single and multiple regression analyses. A design equation for use in the Pavement Design System is presented. It expresses the swelling clay parameter in terms of the plastic, liquid, shrinkage, and linear shrinkage limits.]]></description>
      <pubDate>Sun, 16 Mar 2025 18:13:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/2521862</guid>
    </item>
    <item>
      <title>Realistic Testing Protocols for Evaluating and Promoting Sustainable Technologies for Stabilizing Highly Expansive Clay Soils</title>
      <link>https://trid.trb.org/View/2509295</link>
      <description><![CDATA[Most subgrade soils in Region 6 are problematic because they consist of expansive soils and weak cohesive soils. Much of the observed damage occurring to pavements and other geotechnical assets is directly linked to the shrink-swell characteristics of these highly plastic soils. Extreme weather causes further problems associated with treated bases and subgrades creating hazardous conditions, premature failures, and reduced performance/service life. This research will explore possible ways to enhance the durability of stabilized geomaterials using innovative next-generation materials including: geopolymers, enzymes, acid-based additives, and other non-calcium-based stabilizers. This study will develop realistic laboratory evaluation techniques for documenting the benefits of these non-traditional stabilizers for both soil stabilization and full depth reclamation purposes. The treatments that perform well in the laboratory will be implemented, where possible, in the field in on-going DOT projects. Additionally, a comparison will be made to traditional stabilizers and a cost-benefit analysis performed to document both financial and environmental saving from the new treatments. 
The case for this research is based on the fact that the only successful widely used traditional stabilizers for Region 6 expansive soils continue to be either lime or cement. These treatments have a solid record and decades of performance history, but non-standard stabilizers continue to be developed, and if successful, could address many of the current environmental concerns as well as the potential secondary issues relating to calcium-based stabilizers such as sulfate heave. These non-standard stabilizers could also offer cost-effective alternatives to the traditional stabilizers, but only if they are shown to be effective long-term. This project will develop realistic laboratory testing procedures which mimic field conditions and develop testing guidelines and criteria that can be used to demonstrate the performance of non-standard stabilizers with site-specific materials. The following tasks will be pursued. Task 1: Literature search; Task 2: Identify applications where non-standard stabilizer should be considered; Task 3: Identify commercially available non-standard stabilizers; Task 4: Develop lab testing protocols and procedures; Task 5: Perform case study testing; Task 6: Develop qualification testing guidelines and acceptance criteria; Task 7: Recommend test sections.

]]></description>
      <pubDate>Thu, 13 Feb 2025 15:11:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/2509295</guid>
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