Soil stabilization

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

Experimental insights of using waste marble fines to modify the geotechnical properties of a lateritic soil

Abstract: Marble spoil waste is an environmental nuisance. The effects of adding waste marble fines (WMF) on the plasticity, strength and permeability of a lateritic clay have been investigated for its potential use as a soil modifier or stabilizer of road pavement layer materials or earth-building materials. The chemical compositions of the WMF and soil were determined using X-ray fluorescence and atomic absorption spectrometry, respectively. The specific gravity, Atterberg limits, compaction, strength and permeability characteristics of the soil were determined for varying proportions of the soil-WMF blends. The properties of the natural soil–classified as clay of low plasticity (CL) and A-7-6(7), according to unified soil classification and AASHTO classification systems, respectively–were improved after the addition of 10% WMF such that it behaves like a silt of low plasticity. Therefore, WMF is recommended as a low-cost soil modifier or stabilizer for lateritic soil and well-suited for road construction applications

Review of current and future bio-based stabilisation products (enzymatic and polymeric) for road construction materials

Abstract: In situ soil modification is required in order to improve the primary engineering properties of the material to meet a road construction standard. Bio-stabilised soil is an environmentally friendly, cost-effective alternative to imported granular fills, concrete, costly hauling of materials or export to a landfill. In-service soil performance and required maintenance is highly dependent on methods of stabilisation, ranging from expensive mechanical stabilisation to chemical processes. As such, many alternative materials originating from bio-based sources are being explored as potential stabilising additives to improve weak subgrade soils (i.e., dispersive, erodible and collapsible soil, and soft or expansive clays). Some key solutions include the use of bio-derived enzymes, microbes, and polymeric additives to avert road failure caused by water penetration and/or erosion. The role of microbial substrate specialisation has been largely unexplored, since the level of research done on alternative stabilisers consists mostly of small ad hoc studies. In addition, research has focused on a reduction in permeability and an increase in compressive strength using enzymes and polymers, however, the complexity of these products and their implementation for a wide range of soil types and structural applications remain limited. Currently there is a need for more supporting research methodologies and systematic approaches on the implementation of bio-based materials for infrastructure development. This also includes the simplification of bio-based products for potential construction applications. This review provides (a) an overview of soil stabilisation techniques, (b) the primary challenges that lay ahead for future research in bio-based stabilisation products application in the road sector and (c) innovations to address the challenges of using modernised techniques in the road construction industry (i.e., weak subgrade and the required maintenance thereof, as well as the development of potential bio-based additives for unpaved road construction application).

Design and construction of airport pavements on expansive soils

Abstract: This investigation reviewed the current engineering literature and synthesized from it a design procedure for stabilizing expansive soils beneath airport pavements. To do this, the study was divided into specific areas: Methods of identifying and classifying the types of soil that are considered expansive and cause early pavement distress; Laboratory and field test methods to determine the level of expansion and shrinkage, i.e., prediction of heave; and the design of stabilized soil layers including (a) selection of the type and amount of stabilizing agent (such as lime, cement, or asphalt), (b) test methods to determine the physical properties of stabilized soil, (c) test methods to determine the durability of stabilized soil, and (d) field construction criteria and procedures. The conclusions and recommendations are based on the current literature, without laboratory verification. Soil-volume changes caused by factors such as frost heave and salt heave were not studied. It was found that while procedures for soil stabilization have improved significantly, the test methods that were developed do not provide a marked improvement over those currently used.

Stabilization of expansive clay soils

Abstract: Natural hazards cause billions of dollars of damage to transportation facilities each year--only flooding causes more damage than expansive soils. Nearly all types of transportation facilities have been affected by expansive soil behavior and, as a result, many have failed or are no longer serviceable. It is imperative that the damage caused by expansive soils be controlled, and proper application of soil stabilization methods can significantly reduce the damage that results from these problem soils. The purpose of this presentation is to discuss the phenomena associated with stabilizing these soils, their behavioral patterns that affect stabilization, and the initial and remedial stabilization methods that can be applied to them. The factors considered include conditions requiring and allowing stabilization, changes of properties with time, the effects of stress history and desiccation, the influence of climate, and the effects of physicochemical environments. Effects that can be improved by stabilization are pinpointed. Stabilization methods are described that improve selected properties of expansive soils by mechanical and chemical means. Well-established methods are discussed along with those that are very promising. Examples of remedial treatments are discussed. It is concluded that there is a need for analyses of all alternatives and for stabilization during construction rather than costly remedial projects. Research needs are outlined that can improve our understanding of the stabilization requirements of these problem soils.

Mechanical Behavior and Sulfate Resistance of Alkali Activated Stabilized Clayey Soil

Abstract: Clayey subgrade soil requires treatment in order to make the subgrade stable for pavement structures. Treatment of clayey soil i.e. stabilization of clayey soil by cement, lime, and fly ash are established techniques used in geotechnical and highway engineering. Stabilization by alkali activation of fly ash is reported recently but literatures are limited. Present study investigates the stress strain behavior, peak stress and ultimate strain of clayey soil stabilized by slag and slag-fly ash blending by alkali activation. The peak stress as high as 25.0 N/mm2 may be obtained at 50% slags content when 12 molar sodium hydroxide solutions were used. Peak stress, ultimate strain and slope of stress–strain curve of stabilized clay are controlled by Na/Al and Si/Al ratios. Stress–strain response and peak stress of slag and fly ash blended specimen are not governed by Na/Al and Si/Al ratios; rather the behavior is dependent predominantly on slag content.