Download or read book Results of Tests to Determine the Feasibility of Stabilizing Soils Containing Gypsum with Lime and Cement written by United States. Army. Corps of Engineers. Ohio River Division Laboratories and published by . This book was released on 1964 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Results of Tests to Determine the Feasibility of Stabilizing Soils Containing Gypsum with Lime and Cement written by OHIO RIVER DIV LABS CINCINNATI. and published by . This book was released on 1964 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of the tests reported herein was to evaluate the effectiveness of lime and cement to stabilize a soil containing an appreciable percentage of calcium sulphate, commonly referred to as gypsum. Soil used for the tests was obtained from Perrin Air Force Base, Texas; this soil contains gypsum in its natural state. Conventional laboratory soil tests were used for the determination of the physical properties of the natural soil and to determine what, if any, strength gain or property change resulted when varying percentages of hydrated lime or cement were added to the soil and the mixture allowed to cure for different periods of time. This report contains the results of the laboratory tests conducted, pertinent conclusions, and recommendations as to the test procedures for determining the applicability of using lime or cement to stabilize unusual or so-called 'contaminated' soils. (Author).
Download or read book Technical Abstract Bulletin written by and published by . This book was released on 1967 with total page 752 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Highway Research in Progress written by and published by . This book was released on 1967 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government wide Index to Federal Research Development Reports written by and published by . This book was released on 1966 with total page 1576 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book U S Government Research Development Reports written by and published by . This book was released on 1966 with total page 1304 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Impact of Gypsum Bearing Water on Soil Subgrades Stabilized with Lime Or Portland Cement written by Douglas Mohn and published by . This book was released on 2015 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: Use of calcium based stabilizes to enhance clay's engineering properties is a common practice in road subgrade improvement. The addition of a calcium based stabilizer increases the calcium content of the soil to reduce the diffuse double layer by cation exchange and leads to flocculation and agglomeration of the clay microstructure. The addition of calcium hydroxide (Ca(OH)2) allows cementitious hydrates to form, via pozzolanic reactions, that increase soil strength. Problems can arise when sulfate and alumina are readily available within the natural state of the soil. Reactions can occur that produces the ettringite mineral that can facilitate sulfate induced heave depending on the amount formed. Although sulfate induced heave is caused by ettringite, ettringite is not a direct correlation to heave. Meaning, the presence of ettringite does not automatically indicate swell since ettringite is a necessary component that increases the strength of cement. Ettringite is only problematic when formation occurs after the mineral consumes all available void space. When this occurs, the ettringite mineral will exert and outward pressure from within the soil and cause heaving of the soil. The ultimate goal of this research was to determine if sulfate concentration in water can contribute to, or even cause, sulfate induced heave. There were four tasks identified to achieve this goal: 1) obtain soil samples from areas of concern, 2) subject soil to mechanical and chemical characterization, 3) chemically stabilize soils and subject to swell test, and 4) asses dominant or limiting factor(s) associated with heave by comparison of pre and post characterization.Results demonstrated that pure kaolinite stabilized with 4% lime will swell excessively when subjected to water. Lime and cement stabilization proved successful when swell was below the set threshold of acceptable swell of 1.5%, as set by ODOT Supplemental 1120. Excessive swell was experienced by a high sulfate (SO4) soil that tested positive for gypsum when stabilized with either lime or cement. Cement stabilization of the high SO4 soil exhibited maximum swell being reached three times faster and a higher unconfined compression failure strength than lime stabilization of the same soil. The saturated gypsum water subjected to the stabilized soil had numerically higher swells than stabilized soil subjected to distilled DI water, but was not statistically proven (p>0.05). All soils stabilized, with the exception to kaolinite, had ettringite within the soil with the amount formed varying.
Download or read book Soil Stabilization written by and published by . This book was released on 1966 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Announcements written by and published by . This book was released on 1966 with total page 1026 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bibliography of Scientific and Industrial Reports written by and published by . This book was released on 1966-03 with total page 1324 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Soil Stabilization with Cement and Lime written by Philip Thomas Sherwood and published by Stationery Office Books (TSO). This book was released on 1993 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soil stabilization is the process whereby soils and related materials are made stronger and more durable by mixing with a stabilizing agent. These techniques are used for road construction in most parts of the world, although the circumstances and reasons for resorting to stabilization vary considerably.
Download or read book Stabilization of Bentonite and Kaolinite Clays Using Recycled Gypsum and Liquid Sodium Silicate written by Mehmet Sagnak and published by . This book was released on 2018 with total page 255 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sustainable soil stabilization of clays utilizing chemical agents relies primarily on chemical reactions between additives and soil materials to attain the desired geotechnical properties such as strength, compressibility, and durability. In this regard, the use of chemicals for ground stabilization is one of the most favorable soil improvement techniques to improve weak engineering properties of soils by combining unbound materials through fabricated cementation products. A variety of soil stabilizers are available for ground stabilization and are categorized as “traditional” (Portland cement, fly ash, hydrated lime) and “non-traditional” (liquid alkali activators, sodium silicate, polymers, enzymes). The production of traditional additives (such as Portland cement or hydrated lime) emits large amounts of greenhouse gases (CO2) into the atmosphere worldwide. As a separate problem, an excessive amount of waste materials are produced from the construction and demolition of civil engineering projects around the word, and the disposal cost of the associated waste materials is high. As a result, more recently, the use of nontraditional additives (such as sodium silicate) and recycled materials (such as gypsum) in earthwork projects has become attractive as a replacement for traditional stabilization agents due to their economic and environmental benefits for society. ☐ Blending soil and alkaline solutions fabricates new cementation materials named geopolymers, achieving a sustainable improvement in the engineering properties of soils, which produces similar mechanical performance relative to traditional stabilizers such as Portland cement. Geopolymers can be synthesized using a variety of sources including industrial waste as well as fine materials such as natural clays. ☐ This research investigates the use of two nontraditional stabilizers, recycled gypsum produced from wall plasters (sometimes referred to as “sheetrock” in the United States), and a sodium silicate solution, to enhance the strength of two types of clay soils, Bentonite and Kaolinite. Three different stabilizer combinations are assessed during this study: (1) “gypsum only”, (2) “sodium silicate only”, and (3) a 50/50 combination of “gypsum and sodium silicate”. For both of the clay minerals that were stabilized, as well as the three stabilizer combinations that are denoted above, four levels of additive stabilization were explored, at 3%, 6%, 9% and 12%. After stabilization, specimens were subjected to various curing intervals, including 0, 3, 7, 14, 28 and 56 days of curing, and unconfined compressive strength (UCS) testing was conducted to determine the strength development with curing time for each of the stabilized soil mixtures. The change in the pH values of the additive-soil mixtures at different curing periods was monitored. Additional microstructural characterization tests including x-ray diffraction (XRD), field emission scanning microscopy (FESEM), energy-dispersive X-ray analysis (EDAX), fourier transform infrared spectrometry (FTIR), and the nitrogenbased Brunauer-Emmet-Teller (N2-BET) test were all used to explore and assess changes in the soil microstructure as soil stabilization progressed with curing time. ☐ The UCS test results demonstrate that the use of powdered recycled gypsum, a sodium silicate solution, and their combination all considerably increased the strength of both stabilized clay soils. Strength increases measured for gypsum stabilized bentonite and kaolinite were 4 and 2.5 times greater than the strengths measured for the corresponding untreated clays, respectively, at all stabilizer mix ratios and curing times that were assessed. Similarly, strength increases measured for sodium silicate stabilized kaolinite and bentonite were 3.5 and 3.5times greater than the strengths measured for the corresponding untreated clays, respectively. Strength increases measured for gypsum and sodium silicate (50/50) stabilized kaolinite and bentonite were 3.5and 2.5 times greater than the strengths measured for the corresponding untreated clays, respectively. It should be noted that these strength multipliers are the lower bound of the observed strength gain, and that many of the tested specimens exhibited significantly higher strengths at various stabilizer concentrations and curing times. ☐ The required optimum additive content of stabilizers depended upon the type of soils, and was different for different curing times. In this study, the optimum stabilizer contents were determined based upon the stabilizer mix ratio that yielded the largest gain in strength in the treated specimens after 56 days of curing. The optimum additive contents for bentonite stabilized with gypsum, sodium silicate, and a 50/50 mixture of gypsum and sodium silicate were 3, 12, and 6, respectively. The optimum additive contents for kaolinite stabilized with gypsum, sodium silicate, and a 50/50 mixture of gypsum and sodium silicate were 12, 6, and 6, respectively. As shown, in general, the kaolinite clay needed a higher content of recycled gypsum relative to the bentonite clay, whereas the sodium silicate stabilized kaolinite required a lower content of sodium silicate relative to the bentonite. The combination of recycled gypsum and sodium silicate was found to have benefits regarding the improvement of engineering properties of both soils, with the same amount of admixture (6%) yielding the greatest strength gain for both soils. The observed chemical reactions for all of the soil stabilization processes were time-dependent, especially for the bentonite treated with the combination of recycled gypsum and sodium silicate. ☐ The XRD tests show the formation of new cementation products via the appearance of new diffraction peaks, along with a reduction of the intensities of the peaks corresponding to the aluminum silicate minerals for both of the tested clays. The FESEM tests showed the transformation/modification of the soil microstructure and clay particle surfaces for both of the clays that were tested, and for the three stabilizer combinations that were utilized. Moreover, new crystalline gel (geopolymer) phases of cementation were observed. Alteration of the chemical composition of both treated soils was validated using energy-dispersive X-ray analysis (EDAX). The modifications of the functional groups of both clay minerals were confirmed utilizing Fourier transform infrared spectrometry (FTIR). In general, the nitrogen-based Brunauer-Emmet-Teller (N2-BET) tests showed a decrease in the surface area of both stabilized clays in the longterm for the different stabilizers that were assessed, as cementation products were created and the pore space between the specimens was filled. At some of the intermediate curing times, increases in surface area of the treated specimen were observed; this behavior is attributed to dissolution of the base materials prior to formation of stabilizing cementitious compounds. These N2-BET surface area results are generally consistent with the UCS test results as the strength reported for intermediate curing times is sometimes lower than the initial strengths that were measured. ☐ From the results of this study, it is believed that the combination of recycled gypsum and sodium silicate improves the soil strength properties significantly, offering positive benefit for long-term soil stabilization. The potential for beneficial reuse of waste gypsum can reduce the quantity of this material that ends up in landfills, and the replacement of traditional Portland cement and lime stabilizers with the combination of gypsum and sodium silicate could serve to decrease the emission of greenhouses gases that are associated with the production of these more traditional soil stabilizers.
Download or read book Fundamentals of Ground Improvement Engineering written by Jeffrey Evans and published by CRC Press. This book was released on 2021-09-17 with total page 418 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ground improvement has been one of the most dynamic and rapidly evolving areas of geotechnical engineering and construction over the past 40 years. The need to develop sites with marginal soils has made ground improvement an increasingly important core component of geotechnical engineering curricula. Fundamentals of Ground Improvement Engineering addresses the most effective and latest cutting-edge techniques for ground improvement. Key ground improvement methods are introduced that provide readers with a thorough understanding of the theory, design principles, and construction approaches that underpin each method. Major topics are compaction, permeation grouting, vibratory methods, soil mixing, stabilization and solidification, cutoff walls, dewatering, consolidation, geosynthetics, jet grouting, ground freezing, compaction grouting, and earth retention. The book is ideal for undergraduate and graduate-level university students, as well as practitioners seeking fundamental background in these techniques. The numerous problems, with worked examples, photographs, schematics, charts and graphs make it an excellent reference and teaching tool.
Download or read book Selected Water Resources Abstracts written by and published by . This book was released on 1991 with total page 898 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Soil Stabilization for Roads and Streets written by United States. Army. Corps of Engineers and published by . This book was released on 1961 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government wide Index to Federal Research Development Reports written by and published by . This book was released on 1966 with total page 1030 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Federal Information Processing Standards Publication written by and published by . This book was released on with total page 1228 pages. Available in PDF, EPUB and Kindle. Book excerpt:
