Soil stabilization

About: Soil stabilization is a research topic. Over the lifetime, 3161 publications have been published within this topic receiving 48437 citations.

Stabilization of Clayey Soil using Cement Kiln Waste

Abstract: Day by day increasing demand of cement results in intense collection of kiln dust from cement plants. The disposal of this fine dust becomes an environmental threat. In order to overcome this problem, research is being carried out in different parts of the world to find out the economical and efficient means of using cement kiln dust (CKD) various applications like soil stabilization, cement production, pavements, waste product stabilization, and agriculture and cement products, etc. Keeping in mind the need for bulk use of these solid wastes in India, it was thought expedient to test these materials and to develop specifications to enhance the use of these industrial wastes in soil stabilization. In the course of the study, this research has been able to establish the reactions between soil and cement. It has been established that the chemical compounds found in soil; quartz, feldspar, dolomite, calcite, montmorillonite, kaolinite etc. react with the chemical constituents found in different identified chemical stabilizers. The purpose of using CKD, and the other additives, is to improve the texture, increase the strength and reduce the swell characteristics of the various soils. This paper represents the stabilization of clayey soil using cement kiln waste. The soil taken from Ravendrapadu in Andhra Pradesh containing different properties in various percentages is mixed with CKD in different proportions and parameters like dry density and moisture content are found out. By examining the values obtained ideal values are obtained at 50% proportional mix of CKD in total percentage.

Influence of Steel Slag and Fly Ash on Strength Properties of Clayey Soil: A Comparative Study

Abstract: Construction of structures over weak or soft soils possesses difficulties like differential settlements, poor strength and high compressibility. Clayey soils are poor in strength and they will result in poor pavement support and ultimately affects the pavement performance and its life period. Clayey soil also affects the design and construction of the pavement, resulting in higher cost of construction and early failure of pavement. Various techniques are available like soil stabilization, providing reinforcement etc. to improve load bearing capacity of soil. Soil stabilization is one of the modification technique used to improve the geotechnical properties of soil and has become the major practice in construction engineering which enables the effective utilization of industrial wastes as a stabilizer. This technique becomes more popular because of its easy availability and adaptability. Stabilization is a method of using the available waste materials for the production of low-cost roads construction. The present work describes a study carried out to check the improvements in the properties of Clayey soil with the addition of Fly ash and Steel slag. Fly ash and Steel slag are blended with unmodified soil in varying percentages to obtain the optimum percentage of admixture required for the soil stabilization. In this comparative study laboratory tests such as Atterberg's limit, Compaction test and CBR test were carried out for both modified and unmodified clayey soil. properties of soil can be improved or treated by mixing the appropriate waste materials into the soil. Adequate blending percentage of admixture is necessary to achieve the maximum strength of soil. Million tons of waste materials are produced annually in India and their disposal has become a major environmental concern. Addition of these wastes in stabilization technique makes proper utilization of these wastes and solves the problem of disposal. Fly ash is produced as a by-product from municipal solid waste incinerators and coal fuelled power stations. Steel slag is a by-product produced during the conversion of iron ore or scrap iron to steel. Prabakar et.al (2004) studied the behavioural aspect of soils mixed with fly ash to improve the load bearing capacity of the soil. Zalihe (2003) investigated that fly ash treatment results in reduction in swelling properties of expansive soil. Mehata and parate et.al (2013) observed that fly ash has good potential for use in geotechnical applications. An attempt is made by Satyanarayana et.al (2013) for the utilization of Fly ash in Bulk quantities by adding various percentages of Fly ash to the expansive soils and they verified its behavior. Poh et.al (2006) investigated that use of ground BOS slag fines in the area of soil stabilization. Manso et.al (2013) studied the properties of Ladle Furnace Slag (LFS) and the characteristics of several clayey soils susceptible to improvement with additions of this by-product. Lavanya et.al (2011) has studied the utilization of copper slag in geotechnical applications and its usage as an admixture to improve the properties of problematic soils.

Assessment of the stabilization of heavy metal contaminants in soils using chemical leaching and an earthworm bioassay

Abstract: Soil stabilization is a remedial technique that reduces the exposure of the soil environment to soil contaminants. Its efficacy can be assessed by determining whether the environmental availability of a contaminant decreases following treatment. We evaluated several chemical leaching treatments by assessing both contaminant leachability and bioaccumulation in the earthworm Eisenia fetida, and determined the most effective treatment for achieving soil stabilization. Soil samples contaminated with As, Cd, Cu, Pb, and/or Zn were collected from abandoned mine areas and stabilized by adding limestone and steel slag (5% and 2% w/w, respectively). All leaching and earthworm tests were conducted using both contaminated and stabilized soils. In addition to bioaccumulation in earthworms, several toxicity parameters (number of cocoons, growth changes, and survival rates) were also assessed to determine the effects of the treatments on the earthworms. The study showed that treatment of soil with EDTA-NH4OAc resulted in a significant decrease in contaminant leachability following soil stabilization. There was an increase in survival and growth of earthworms exposed to the stabilized soil compared with those exposed to the non-stabilized soil. Bioaccumulation in earthworms was found to be statistically correlated with the leachability of As by EDTA-NH4OAc. We conclude that limestone and steel slag effectively decreased the availability of heavy metals in the soil and reduced the toxicity to earthworms. Leaching with EDTA-NH4OAc has the potential to be predictive in estimating the bioavailability of As in soils, but further studies are needed if it is to be proposed as a standard method.

The Alternatives to Traditional Materials for Subsoil Stabilization and Embankments

Abstract: Major infrastructure projects require significant amount of natural materials, often followed by the soft soil stabilization using hydraulic binders. This paper presents the results of a laboratory study of alternative waste materials (fly ash and slag) that can be used for earthworks. Results of high plasticity clay stabilization using fly ash from Serbian power plants are presented in the first part. In the second part of the paper, engineering properties of ash and ash-slag mixtures are discussed with the emphasis on the application in road subgrade and embankment construction. Physical and mechanical properties were determined via following laboratory tests: Specific gravity, grain size distribution, the moisture–density relationship (Proctor compaction test), unconfined compressive strength (UCS), oedometer and swell tests, direct shear and the California bearing ratio (CBR). The results indicate the positive effects of the clay stabilization using fly ash, in terms of increasing strength and stiffness and reducing expansivity. Fly ashes and ash-slag mixtures have also comparable mechanical properties with sands, which in combination with multiple other benefits (lower energy consumption and CO2 emission, saving of natural materials and smaller waste landfill areas), make them suitable fill materials for embankments, especially considering the necessity for sustainable development.

Containment, Stabilization and Treatment of Contaminated Soils using Insitu Soil Mixing

Abstract: Soil Mixing is a technique that has increasingly been relied upon for the insitu remediation of contaminated soils. Depending on the application, large or small diameter (4 to 0.3 meter) mixing augers can be used to inject cement, bentonite or other reagents to modify soil properties and thereby remediate contaminated soils and sludges. A major advantage of the method is the capability to treat soils at depth (up to 35 meters deep) without excavation, shoring or dewatering. Recent advances in soil mixing technology include lower permeability additives for groundwater barriers, additives for the fixation of waste-contaminated soils and combination of soil mixing with hot air injection and vapor extraction technology to remove volatile organic chemicals.