Showing papers on "Soil stabilization published in 2003"

Stabilization of Clay Soils with Nontraditional Additives

Abstract: A laboratory experiment was conducted to evaluate the stabilization of low- and high-plasticity clay soils with nontraditional chemical or liquid stabilizers. Clay soil specimens were mixed with various stabilization products and compacted using a gyratory compaction machine to approximate ASTM D1557 moisture—density compaction. Each specimen was subjected to wet and dry testing following a 28-day cure. Twelve nontraditional stabilizers were evaluated, including an acid, enzymes, a lignosulfonate, a petroleum emulsion, polymers, and a tree resin. Additional specimens were stabilized with Type I portland cement and hydrated lime for comparison with traditional stabilizers under the same mixing, compaction, and curing conditions. Analysis of the test data consisted of determining the average strength, in terms of unconfined compressive strength, of three replicate specimens of each mixture. The average strength of the three replicates of each additive was compared with the average strength results of the re...

Engineering Behavior of Stabilized Soils

Abstract: Stabilization of soils is an effective method for improving soil properties and pavement system performance. For many soils, more than one stabilization agent may be effective, and financial considerations or availability may be the determining factor on which to use. A series of tests was conducted to evaluate the relative performance of lime, cement, Class C fly ash, and an enzymatic stabilizer. These products were combined with a total of seven different soils with Unified Soil Classification System classifications of CH, CL, ML, and SM. Durability testing procedures included freeze-thaw, wet-dry, and leach testing. Atterberg limits and strength tests also were conducted before and after selected durability tests. Changes in pH were monitored during leaching. Relative values of soil stiffness were tracked over a 28-day curing period using the soil stiffness gauge. Lime- and cement-stabilized soils showed the most improvement in soil performance for multiple soils, with fly ash-treated soils showing substantial improvement. The results showed that for many soils, more than one stabilization option may be effective for the construction of durable subgrades. The enzymatic stabilizer did not perform as well as the other stabilization alternatives.

Stabilization of fuel oil contaminated soil—A case study

Abstract: Fuel oil contamination brings adverse effect on basic geotechnical properties of foundation soil. The present study pertains to one such case, from the petrochemical complex near Vadodara City in Gujarat State, India. Here, the fuel oil contaminated soil samples exhibit drastic changes in their geotechnical parameters. Noteworthy among such deleterious changes are: decrease in maximum dry density (−4%), cohesion (−66%), angle of internal friction (−23%) and unconfined compressive strength (UCS) (−35%) and increase in liquid limit (+11%). An attempt has been made to stabilize the contaminated soil using various additives viz., lime, fly ash and cement independently as well as an admixture of different combinations. It is apparent from the test results that the stabilization agents improved the geo-technical properties of the soil by way of cation exchange, agglomeration, and pozzuolanic actions. The best results were observed when a combination of 10% lime, 5% fly ash and 5% cement was added to the contaminated soil. The improvement in unconfined compressive strength (UCS), cohesion and angle of internal friction can be attributed to neo-formations such as Calcium Silicate Hydrates (CSH, CSH-1) that coats and binds the soil particles. Formation of stable complex between oil and metallic cations, results in reduction of leachableoil.

Reuse of Incinerator Fly Ash in Soft Soil Stabilization

Abstract: One of the ways in which highly urbanized cities cope with increasing amounts of municipal solid waste (MSW) generated by the population is incineration. As land is a very precious commodity and landfills are fast dwindling in most highly urbanized cities, the disposal of the ash generated from MSW incineration poses increasingly difficult problems for the municipalities. A viable solution to the disposal problems would be the reuse of MSW ash for civil engineering applications. A research study of the properties of the incinerator fly ash derived from MSW incineration indicated that fly ash is a potential source of jet-grouting admixture for soil improvement. The fly ash exhibits a likelihood of pozzolanic reaction due to its chemical composition and physical characteristics. The use of fly ash as an admixture in the stabilization of a soft marine clay resulted in stabilized samples with an improved strength more than 75 times that of the untreated clay. Incorporation of fly ash also improved drainage property by at least one order of magnitude and reduced both the plasticity and compression indices by about 69 and 23%, respectively. Leachate investigation conducted on the fly ash–stabilized soils indicated that chromium was well-below the World Health Organization drinking water limit, while nickel and lead were in excess of the limits. The nickel and lead leachate concentrations diminished to below the acceptable drinking water limits over a period of about 130 and 110 days, respectively.

Ranking of Four Chemical and Mechanical Stabilization Methods to Treat Low-Volume Road Subgrades in Texas

Abstract: Expansive soils encountered in North Texas exhibit low strength properties, as well as high swell and shrinkage characteristics. These soil properties often result in the poor performance of pavement infrastructures, particularly those built for low-volume traffic conditions. Pavement distress caused by differential heaving leads to pavement cracking and ponding problems. This causes riding discomfort for commuters and induces traffic delays due to the continual repair of the pavements. Hence, it is necessary to explore and develop new and alternate stabilization methods to improve stabilization of expansive soils. Laboratory investigations were designed and conducted on four local expansive soils stabilized with low-calcium Class F fly ash, Type V sulfate-resistant cement, ground granulated blast furnace slag (GGBFS), and lime mixed with fibers. Test results were analyzed and ranked by well-established scales to select the top-performing stabilizers. Results showed that the sulfate-resistant cement, followed by the lime with fibers and the GGBFS stabilization methods, provided effective stabilization of soft and expansive soils. Ranking assessments were performed, and a few important conclusions on stabilization mechanisms were drawn.

Factors affecting strength gain in lime-cement columns and development of a laboratory testing procedure

Abstract: Lime-cement columns were constructed to improve soft ground as part of a test embankment program at the I-95/Route 1 interchange in Alexandria, Virginia. Two different commercial laboratories performed tests on treated soil, and they produced very different measurements of unconfined compressive strength. Further, both sets of results were different from test results available in the published literature for similar soils. This situation created uncertainties and a conservative design philosophy. The goals of this research project were to assess factors that influence strength gain of lime-cement-soil mixtures, to develop a detailed laboratory test procedure that produces consistent results, and to determine the reasons that the strengths measured by the private firms were so different. A suitable laboratory procedure was developed and applied to three soils: one from the I-95/Route 1 interchange site and two from the site of a potential future application of lime-cement columns in West Point, Virginia, at State Route 33. Key findings from the research were that (1) drying and subsequent restoration of soil moisture prior to treatment can decrease the strength of the mixture, (2) the mixture strength decreases as the ratio of soil water content to cement content increases for 100% cement-soil mixtures, (3) the addition of lime can increase the mixture strength for some soils and decrease the strength for others, and (4) presenting the test results in the form of contour plots of unconfined compressive strength can be very useful. The reasons for the different results from the two private firms are explained by differences in the test procedures that were used.

An analysis of the mechanisms and efficacy of three liquid chemical soil stabilizers: volume 1

Abstract: Liquid chemical products are marketed by a number of companies for stabilizing pavement base and subgrade soils. If effective, these products could be used as alternatives for treating sulfate-rich soils, which are susceptible to excessive heaving when treated with traditional, calcium-based stabilizers like lime, cement, and fly ash. However, the chemical composition, stabilizing mechanisms, and performance of these liquid products are not well understood. The primary objective of this study was to investigate and identify the mechanisms by which clay soils are modified or altered by these liquid chemical agents. Three representative, commercial products were selected for study: an ionic product, an enzyme product, and a polymer product. The chemical composition of each was characterized using standard chemical test methods. The three products were then reacted with three reference clays (kaolinite, illite, and montmorillonite) and several native Texas soils. In the "micro-characterization" study, the mechanisms of soil modification at the particle level were studied using physical-chemical analyses of untreated and treated soil samples. Very high product application rates were used so that possible soil modifications could be observed. In a paired "macro-characterization" study, standard geotechnical laboratory tests were performed on untreated and treated compacted soil specimens. The products were mixed at the suppliers' recommended application rates and at ten times the recommended application rates. These tests failed to show significant, consistent changes in the engineering properties of the test soils following treatment with the three selected products at the application rates used. The findings of this study clearly point to the need to conduct standard laboratory tests, prior to specifying the use of these products in field applications, to prove the effectiveness of the treatment on a particular soil type at a given chemical application rate.

Stabilization of sulfate-containing soil by cementitious mixtures mechanical properties

Abstract: Winn Rock (CaSO4) gravel from a quarry in Winn Parish in north Louisiana was used extensively as a surface course for local parish roads. Stabilization of these roads with Type I portland cement followed by an overlay of asphaltic concrete resulted in heaving. A study was undertaken to investigate the cause or causes of the expansion as well as to identify an alternate means of stabilization. Specimens of representative soil from the affected area were stabilized in the laboratory using various cementitious materials and were cured using a variety of methods. The mix contained 5% to 20% cementitious material. The cementitious materials were Type I portland cement, lime, and supplementary cementing materials such as granulated blast furnace slag (BFS), Class C fly ash (CFA), silica fume, and an amorphous silica (AS). The uncon-fined compressive strength of the stabilized soil was determined. The effect of size fractions other than the gravel on the expansion was assessed, and the expansion of the specimens...

Lime slurry stabilisation of an expansive soil

Abstract: Lime slurry and lime pile techniques are viable choices for in-situ stabilisation of expansive soil deposits. This paper reports the results of a laboratory study on in-situ chemical stabilisation of an expansive soil that permeated lime slurry through an artificially desiccated expansive soil specimen. The soil was desiccated in the laboratory to induce shrinkage cracks in the compacted expansive soil. The shrinkage cracks greatly assisted migration of lime slurry in the expansive soil mass. The efficiency of lime slurry in chemically stabilising the desiccated expansive soil was investigated by comparing the physico-chemical properties and engineering properties of the treated soil with those of the natural soil specimen at two radial distances. Experimental results indicated that migration of lime slurry through the desiccated soil promoted strong lime modification and pozzolanic reactions in the soil mass. The strong soil–lime reactions rendered the soil less plastic, reduced the swell magnitude, and ...

New Approach to Limit Equilibrium and Reliability Analysis of Soil Nailed Walls

Abstract: A new approach to the limit equilibrium method is developed and used for the analysis of soil nailed walls. The basic procedure of the new approach is to compute the interslice forces by recursion and to fulfill the equilibrium requirement for interslice forces of the last boundary slice by iteration. Reliability analysis for soil nailed walls is carried out by considering the cohesion and internal friction angle of soil as random variables. The degree of mobilization of friction resistance between the nails and surrounding soil is taken as a third random variable. A parametric study is carried out to study the effect of soil behavior and the arrangement pattern of nails on the factor of safety and reliability index. Finally, an optimization technique is employed to obtain the minimum cost design of soil nailed walls with an object function expressed by the total nail length, which is considered an appropriate measure of the total cost of a soil nailed wall.

Thermochemomechanical assessment of ground improvement by jet grouting in tunneling

Abstract: Horizontal jet grouting (HJG) is employed in urban tunneling in order to reduce surface settlements and, hence, to avoid damage of infrastructure and surface buildings. The widespread use of HJG raises the question of its efficiency. In order to answer this question, sophisticated thermochemomechanical material models for jet-grouted soil mass and shotcrete are employed in the context of plane-strain finite element analyses. For these analyses, the process of ground improvement, the excavation of the tunnel, and the installation of the shotcrete lining are considered. The obtained results provide first insight into the load-carrying behavior of the compound structure consisting of the jet-grouted soil mass, the shotcrete lining, and the surrounding soil. The influence of the different creep characteristics in jet-grouted soil mass and shotcrete, resulting in a redistribution of loading, is highlighted. Moreover, the reduction of plastic loading of the soil in consequence of HJG, which is described by means of a multisurface viscoplasticity model, is illustrated. Based on the obtained numerical results, application of HJG results in a reduction of the surface settlement by more than 50% in comparison to a tunnel which is only supported by a shotcrete lining.

Hurricane Mitch: effects on mangrove soil characteristics and root contributions to soil stabilization

Abstract: Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. iv Tables Table 1. Physicochemical characteristics of soil strata at different hurricane impact sites on the Caribbean (Bay Islands) and Pacific (Gulf of Fonseca) Coasts of Honduras in January 2000. Table 2. ANOVA results for physical characteristics of surface soils collected from (a) Caribbean (Bay Islands) and (b) Pacific (Gulf of Fonseca) Coasts of Honduras in January 2000. Table 3. Physicochemical characteristics of surface soils collected at two impact levels on the Caribbean (Punta Manabique) Coast of Guatemala. Table 4. ANOVA results for physicochemical characteristics of surface soils collected from (a) Caribbean (Bay Islands) and (b) Pacific (Gulf of Fonseca) Coasts of Honduras in January 2000 and 2001. Table 5. ANOVA results for root production by size class (fine and coarse) measured on the Caribbean (Bay Islands) and Pacific (Gulf of Fonseca) Coasts of Honduras. v Figures Figure 1. Selected soil stratigraphy profiles in January 2000 at shoreline and interior plots established at different impact levels on the Caribbean (Bay Islands) and Pacific (Gulf of Fonseca) Coasts of Honduras (A) and on the Caribbean (Punta Manabique) Coast of Guatemala (B). Figure 2. Bulk density (with mineral and organic components and relative saturation of soil measured in January 2000 at shoreline and interior plots established at different impact levels on the Caribbean (Bay Islands) and Pacific (Gulf of Fonseca) Coasts of Honduras. Figure 3. Soil shear strength measured in January 2001 at the soil surface and at depth at shoreline and interior plots established at different impact levels on the Caribbean (Bay Islands) and Pacific (Gulf of Fonseca) Coasts of Honduras. Figure 4. Pore water salinity, pH, and sulfide concentrations measured in January 2000 and 2001 at shoreline and interior plots established at different impact levels on the Caribbean (Bay Islands) and Pacific (Gulf of Fonseca) Coasts of Honduras. Figure 5. Soil redox potentials (E h) measured in January 2000 and 2001 at shoreline and interior plots established at different impact levels on the Caribbean (Bay Islands) and Pacific (Gulf of Fonseca) Coasts of Honduras. Figure 6. Pore water NH 4-N and PO 4-P concentrations measured in January 2000 at shoreline and interior plots established at different impact levels on the Caribbean (Bay Islands) and Pacific (Gulf of Fonseca) Coasts of Honduras. vi Figure 7. Belowground root production (to …

Stabilizing Unpaved Roads with Calcium Chloride

Abstract: The U.S. Department of Agriculture Forest Service has stabilized unpaved road surfacing materials with relatively high concentrations of calcium chloride salt. The percentage of calcium chloride is higher than that traditionally used for dust abatement or aggregate base stabilization. Up to 2% pure salt by weight of aggregate was mixed into the top 2 in. (50 mm) of both aggregate and native road surfaces. The results were monitored for 2 to 4 years. The stabilized road surfaces resisted raveling and washboarding for several seasons and significantly reduced road blading and aggregate loss. As a result, calcium chloride stabilization may be a cost-effective treatment for roads with daily traffic volumes less than 200. Other benefits include reduced surface erosion and sedimentation; improved safety from reduced dust, raveling, and washboarding; and less frost penetration. Encouraged by these results, the Forest Service is conducting additional evaluations to determine the cost-effectiveness of surface stab...

Evaluation and Quality Control of Dry-Jet-Mixed Clay Soil-Cement Columns by Standard Penetration Test

Abstract: Dry jet mixing has been widely used since the 1980s for stabilization of soft soil. The quality and strength of the dry-jet-mixed columns must be evaluated to confirm the success of the stabilization. The standard penetration test (SPT) is shown to be a simple and effective method for this task. The strength characteristics along the length of the column were determined, and correlations between the SPT blow count and the unconfined compressive strength were developed.

Evaluation of Hexahydrated Magnesium Chloride Performance as Chemical Stabilizer of Granular Road Surfaces

Abstract: The performance was evaluated of hexahydrated magnesium chloride (MgCl2· 6H2O) as a chemical stabilizer of granular road surfaces. MgCl2· 6H2O is a salt with properties that are useful for chemical stabilization of granular road surfaces, such as its capacity to absorb and retain humidity from its surrounding environment, increase water surface tension, and decrease water vapor pressure. Its effect on the physical and mechanical properties of soils was evaluated in laboratory, and its functional performance and durability were evaluated in field trials. Field trials were performed in arid and semiarid regions in the Atacama Desert in northern Chile. Field results showed that roads stabilized with MgCl2· 6H2O remain free of dust and corrugations and exhibit a considerable reduction in pot-holes and surface erosion. The period of effectiveness for MgCl2· 6H2O has proven to be more than 2 years, without any type of road maintenance.

Performance characteristics of soil-cement from industry waste binder

Abstract: The performance characteristics of soil-cement with industry waste binder as the stabilizer (designated as industry waste soil-cement) were studied in terms of mix proportions, bulk density, and unconfined compressive strength (UCS). The industry waste binder in this study was prepared by blending ground granulated blast furnace slag (GGBS), fly-ash, dried lime sludge (DLS) from the acetylene industry, and natural anhydrite with certain specific surface areas in mix proportion. Soil-cement with ordinary Portland cement as the stabilizer (designated as OPC soil-cement) was used as the control sample. The aim of this study was to check the feasibility of substituting industry waste binder for ordinary Portland cement in stabilization of soft soils. The results of the laboratory tests indicated that the UCS of industry waste soil-cement was strongly dependent on the mix proportions of the binder (especially the content and fineness of GGBS and lime content) for a given soil, that the bulk density of industry waste soil-cement was nearly equal to that of OPC soil-cement, and that the industry waste binder optimized produced higher strengths than OPC under the same conditions. This result suggests that industry waste binder is promising for stabilization of soft soils in civil engineering construction.

Laboratory and field evaluation of cement kiln dust and lime for stabilizing clayey silt on low-volume unpaved roads

Abstract: The potential of cement kiln dust (CKD) and lime (quicklime) for stabilizing low-volume unpaved roads on sites dominated by cohesive soils was investigated. CKD, lime plus CKD, lime, and portland cement were tested at different mixtures and soil moisture contents in a clayey silt to determine the resulting unconfined compressive strength after three curing periods. In a field study, road sections were stabilized with CKD and with lime plus CKD, and then a gravel running surface was added. Soil penetration resistance increased after the treatment. Field results confirmed the laboratory results and helped identify the most effective treatment. Stabilization proved cost-effective for new roads in areas where gravel is difficult to obtain.

Evaluation of Fly Ash and Clay in Soil Grouting

Abstract: Improvement of the mechanical and hydraulic properties of soils by grouting is one of the most widely used techniques in soil stabilization. The use of added pozzolanic materials such silica fume, and fly ash as well as clay to improve the physical, mechanical, and fluidity properties of cement grouts has been researched in recent years. In this study, the usage of grout additives fly ash and clay in soil grouting, and the effects of these grouts on soil strength have been researched in laboratory tests. First, grouts with added fly ash and clay in different amounts were prepared, and then these grouts were injected into soil samples. The unconfined compressive strength of grouted samples was determined for 7 and 28 days of curing time. It is shown that fly ash and clay improved fluidity of the grouts. The results of fly ash and clay grouted samples were compared with the cement grouted samples and the test results were evaluated against each other.

Stabilization techniques for reactive aggregate in soil-cement base course : technical summary.

Abstract: Anhydrite (CaSO4) beds occur as a cap rock on a salt dome in Winn Parish in north Louisiana. Locally known as Winn Rock, it has been quarried for gravel for road building. It has been used as a surface course for local parish and logging roads. Stabilization of these roads with Type I portland cement followed by an overlay of asphaltic concrete sometimes resulted in heaving. The causes of heaving and possible solutions were investigated. In the laboratory, 2 in. x 4 in. molds of Winn Rock containing soil were stabilized with various cementitious mixes and cured in a 40 deg C water bath, in a 100% relative humidity room, in a sealed plastic bag at room temperature, and in air. The mixes contained 5% to 20% cementitious material. The cementitious materials were Type I portland cement, lime, and supplementary cementitious materials (SCM) such as granulated blast furnace slag (BFS), Class C fly ash, silica fume and amorphous silica. The expansion of the specimens over time was monitored. Mineralogical and microstructural analyses of the specimens were also performed over time and correlated to expansion. The Winn Rock gravel was partially weathered in the soil to gypsum, which was detected in all size fractions. The highest amount of expansion occurred in Winn Rock soil stabilized by lime cured at 40 deg C in a water bath. The magnitude of the expansion is directly proportional to the amount of Type I portland cement, the amount of available moisture, and the curing temperature. Replacement of a part of the portland cement by BFS reduced the expansion by almost an order of magnitude even at the highest moisture content. No expansion was detected when a mixture of Class C fly ash and amorphous silica was used as a partial replacement. The costs of portland cement and blast furnace slag mixtures are less than the cost of portland cement only. The addition of amorphous silica or silica fume to the cementitious mix will increase the cost significantly.

Stabilization Techniques for Reactive Aggregate in Soil-Cement Base Course

Abstract: Anhydrite (CaSO4) beds occur as a cap rock on a salt dome in Winn Parish in north Louisiana. Locally known as Winn Rock, it has been quarried for gravel for road building. It has been used as a surface course for local parish and logging roads. Stabilization of these roads with Type I portland cement followed by an overlay of asphaltic concrete sometimes resulted in heaving. The causes of heaving and possible solutions were investigated. In the laboratory, 2 in. x 4 in. molds of Winn Rock containing soil were stabilized with various cementitious mixes and cured in a 40 deg C water bath, in a 100% relative humidity room, in a sealed plastic bag at room temperature, and in air. The mixes contained 5% to 20% cementitious material. The cementitious materials were Type I portland cement, lime, and supplementary cementitious materials (SCM) such as granulated blast furnace slag (BFS), Class C fly ash, silica fume and amorphous silica. The expansion of the specimens over time was monitored. Mineralogical and microstructural analyses of the specimens were also performed over time and correlated to expansion. The Winn Rock gravel was partially weathered in the soil to gypsum, which was detected in all size fractions. The highest amount of expansion occurred in Winn Rock soil stabilized by lime cured at 40 deg C in a water bath. The magnitude of the expansion is directly proportional to the amount of Type I portland cement, the amount of available moisture, and the curing temperature. Replacement of a part of the portland cement by BFS reduced the expansion by almost an order of magnitude even at the highest moisture content. No expansion was detected when a mixture of Class C fly ash and amorphous silica was used as a partial replacement. The costs of portland cement and blast furnace slag mixtures are less than the cost of portland cement only. The addition of amorphous silica or silica fume to the cementitious mix will increase the cost significantly.

Development of stabilizer selection tables for low-volume roads: arlington, texas

Abstract: Expansive soil movements cause damage to low-volume traffic roadways, which is attributed to the low rigidity of the materials used in the pavements. Several treatment methods have been used to stabilize expansive, soft subsoils, which have yielded mixed results due to the presence of sulfates. Because of the ambiguity of these results, the city of Arlington, Texas, established a task force of researchers and practitioners in the area of soil stabilization to develop matrix tables of the various treatment methods and their applicability to stabilize expansive, soft, and sulfate-rich soils. Extensive literature compiled on the stabilizers, several new and previous research studies on stabilizers, and the expertise of the task group members were considered in the evaluation process. The task force developed seven matrix-form selection tables that showed various treatment methods and if their applications were acceptable or unacceptable for the 12 types of soft and sulfate-rich subgrade soils. A summary of t...

Use of Locally Available Soils on Subbase and Base Layers of Flexible Pavements

Abstract: Lateritic soils are very abundant in the region of the Federal District of Brazil. If this material could be used in low-volume roads, it would be possible to avoid some environmental problems. Alternative techniques were developed for the use of nonconventional materials as subbase and base layers of flexible pavements. To analyze the technical and economical viability of using local soils, two experimental highways were constructed. Each highway was divided into three sections with different materials in the subbase and base layers, such as fine lateritic soil, fine lateritic soil stabilized with lime, and a mixture of fine lateritic soil and crushed rock. The compaction characteristics were evaluated in laboratory tests. From the time the segments were constructed (in 1998 and 2000) until 2001, the stress-strain behavior of the paving structures was evaluated by in situ tests, such as the plate-bearing, Benkelman beam, and falling weight deflectometer tests. From the results, conclusions were drawn about which of the chosen materials showed the best performance in mechanical behavior.

Admixture for soil stabilization and engineering method for stabilizing soil by using the same

Abstract: PROBLEM TO BE SOLVED: To provide a non-cement-based admixture for soil stabilization not completely containing cement, modifying muddy soil or dried soil to stable soil in a natural state in a short time and capable of solidifying the soil again by subsequent compaction even when the modified soil is re-stirred and to provide an engineering method for stabilizing the soil by using the admixture SOLUTION: The admixture for soil stabilization is obtained by mixing 100 ptswt ash component with 1-39 ptswt blast furnace slag fine powder, 2-42 ptswt slaked lime, 01-25 ptswt magnesium hydroxide and 01-25 ptswt muddy soil The method for stabilizing the soil comprises mixing 100 ptswt muddy soil with 1-20 ptswt of the admixture for soil stabilization under stirring and laying the mixture on the ground and compacting the mixture COPYRIGHT: (C)2004,JPO

Effects of Kiln Ash on the Compressibility of Residual Lateritic Soils

Abstract: The potential for the use of kiln ash as an additive to Lateritic soils to improve their engineering characteristics as road construction material was experimentally investigated. The results of laboratory tests indicate that no significant improvement of the soil properties occurred until after several weeks of curing time. In general, as the content of kiln ash in the soil was increased, the soil pH increased from 5.5 to 11.8; the maximum unconfined shear strength increased from 340 to 423 kPa (corresponding to 0–8% kiln ash content), the soil liquid limit reduced from 59 to 49% (corresponding to 0–20% kiln ash as content). No significant change in the plasticity limits of the lateritic soil was observed, in the range of 0 to 8% kiln ash content. Relative to the compressibility of the natural soil (measured in terms of the total strain), a decrease of about 3% occurred for kiln ash contents of 5, 10, and 20% within 1 to 7 days; and that this decrease reached about 19% for 20% kiln ash content as time pr...