Soil stabilization

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

An Investigation of Treatment Effects of Limestone and Steel Refining Slag for Stabilization of Arsenic and Heavy Metal in the Farmland Soils nearby Abandoned Metal Mine

Abstract: A soil stabilization method is an effective and practical remediation alternative for arsenic (As) and heavy metal contaminated farmland soils nearby abandoned metal mine in Korea. This method is a technique whereby amendments are incorporated and mixed with a contaminated soil. Toxic metal bind to the amendments, which reduce their mobility in soil, so the successful stabilization of multi-element contaminated soil depends on the combination of critical elements in the soil and the type of amendments. The objective of this study is to investigate the treatment effects and applicability of limestone (LS) and steel refining slag (SRS) as the amendment for farmland soil contaminated with As and heavy metals, and a lab-column test was conducted for achieving this purpose. The result showed that soil treated with LS and SRS maintained pH buffer capacity and, as a result, the heavy metal leaching concentration was quite low below the water quality standard compared to untreated soil which leachate exceeding the water quality standard was observed, however, the arsenic concentration rather increased with increasing mixture ratio of SRS. This was believed to be related to phosphorus (P) contained in SRS, and dominancy in the competitive adsorption relation between As and P binding strongly to iron might be different according to soil characteristic. We suggested that LS is a effective amendment for reducing heavy metals in soil, and SRS should be used after investigating its applicability based on the adsorption selectivity of arsenic and phosphorus in selected soil.

Tensile Fracture and Fatigue of Cement Stabilized Soil

Abstract: Portland cement stabilized soil is widely used as a base material for roads, airfields, and similar structures. Cracking in this material is studied using fracture mechanics concepts. Fracture toughnesses in the form of the plane strain stress intensity factor and in the form of the J-integral are used as primary descriptors in the study. A simple power law is used in the case of fatigue loading to describe the relationship between the change in crack length per load cycle and the fluctuation in the stress intensity factor. Approximate relationships are developed which define the relationship between the physical and chemical nature of the material and its engineering usage. These relationships consider cement content, compactive effort, and fracture toughness.

Utilization of Soil Stabilization with Cement and Copper Slag as Subgrade Materials in Road Embankment Construction

Abstract: In this study, unconfined compression tests have been conducted to investigate the impacts of copper slag on mechanical characteristics for stabilized cement and un-stabilized soil. Dozens of specimens were prepared at four percentages of cement (i.e. 0%, 2%, 4% and 6%) and five percentages of copper slag (i.e. 0%, 5%, 10%, 15% and 20%) by weight of dry soil. The samples compacted into a cylindrical specimen and processed for the curing periods of 28, 60 and 90 days. The test results indicated that the inclusion of copper slag had a significant effect on the unconfined compressive strength (UCS). For cement stabilized specimens, the improvement impacts of the copper slag on the UCS was more tangible than un-stabilized ones. Furthermore, an increase in the UCS was most apparent in the 2% cemented specimen wherein the UCS increased more than 78% as the copper slag increased up to 20%. Moreover, it was evident that the more amount of copper slag increased, the more optimum moisture content (OMD) declined and additionally maximum dry density (MDD) of soil was on the rise, while the results of the increase in cement was quite the reverse. Moreover, an artificial neural network (ANN) model has been developed using eight input parameters including: copper slag content, cement content, water content, dry density, liquid limit, plastic limit, PH and curing age. An ANN network, composed of 10 neurons in a hidden layer, was considered as the appropriate architecture for predicting the elastic modulus of mixtures, and an excellent conformity was acquired between the observed test data and the predicted ones. The results was proven that the proposed model can be efficiently applied to predict the elastic modulus of stabilized soils.

Coal Fly Ash Trace Element Mobility in Soil Stabilization

Abstract: Many coal combustion by-products (CCBs) have advantageous properties for engineering, construction, and manufacturing applications. 2, 3 CCBs have properties that are beneficial in soil stabilization applications such as soil drying, a soil amendment to enhance subgrade support capacities for pavements and floor slabs, reduction of shrink–swell properties of soils, and a stabilizer in aggregate road base construction and asphalt recycling. Approximately 31% of all U.S. CCBs (fly ash, bottom ash, boiler slag, and flue gas desulfurization materials) produced in 1999 were utilized. Six percent of the utilized fly ash and 20% of the utilized bottom ash was used in road base and subbase applications in 1999. The typical usage rate of CCBs for soil stabilization applications is 6%–15%, although this varies on the basis of engineering performance in prescribed laboratory tests.

Compressive Strength of Soil Improved with Cement

Abstract: The soil type can affect significantly the effect of cement stabilization. In order to investigate this, five types of soils were mixed with cement at various cement proportions in order to evaluate the large variation of compressive strength values. The compressive strength of the cement treated soils was determined for a curing period of the cement equal to 7 and 28 days. It was obvious that the soil type is a controlling factor on the rate of increase of compressive strength with increasing cement content. Other factors affecting strength are the curing time of cement and the optimum water content.