This report presents information on the characterization of cementitiously stabilized layers and the properties that influence pavement performance. It also contains recommended performance-related procedures for characterizing these layers and performance-prediction models for incorporation into the mechanistic–empirical pavement analysis methods. Individual chapters highlight pavement distresses of hot-mix asphalt pavements and concrete pavements, laboratory tests and model development, and model calibration. The material contained in the report will be of immediate interest to state materials, pavement, and construction engineers and others involved in the different aspects of pavement design and construction.

Characterization of Cementitiously Stabilized Layers for Use in Pavement Design and Analysis

Geosynthetic-encased stone columns: Numerical evaluation

Clayey soils are usually stiff when they are dry and give up their stiffness as they become saturated. Soft clays are associated with low compressive strength and excessive settlement. This reduction in strength due to moisture leads to severe damages to buildings and foundations. The soil behavior can be a challenge to the designer build infrastructure plans to on clay deposits. The damage due to the expansive soils every year is expected to be $1 billion in the USA, £150 million in the UK, and many billions of pounds worldwide. The damages associated with expansive soils are not because of the lack of inadequate engineering solutions but to the failure to identify the existence and magnitude of expansion of these soils in the early stage of project planning. One of the methods for soil improvement is that the problematic soil is replaced by suitable soil. The high cost involved in this method has led researchers to identify alternative methods, and soil stabilization with different additives is one of those methods. Recently, modern scientific techniques of soil stabilization are on offer for this purpose. Stabilized soil is a composite material that is obtained from the combination and optimization of properties of constituent materials. Adding cementing agents such as lime, cement and industrial byproducts like fly ash and slag, with soil results in improved geotechnical properties. However, during the past few decades, a number of cases have been reported where sulfate-rich soils stabilized by cement or lime underwent a significant amount of heave leading to pavement failure. This research paper addressed the some fundamental and success soil improvement that used in civil engineering field.

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Fundamentals of soil stabilization

Bearing capacity of square footings on geosynthetic reinforced sand

Soil stabilization is a technique to improve the engineering and geotechnical properties of soils such as mechanical strength, permeability, compressibility, durability and plasticity. Much has been learned about soil stabilization techniques and additives over the past century. The state of the practice in stabilization techniques and challenges is presented with a discussion. Moreover, available studies regarding the effects of various types of stabilizing agents on the engineering and geotechnical properties of stabilized soils are reviewed here. These stabilizing agents include both calcium-based and non-calcium-based additives. Eco-friendly additives as alternative materials to conventional stabilizing agents are also discussed in this paper. In addition, the problems associated with the presence of disruptive salts and sulfate as well as the techniques to overcome these problems in soil stabilization projects are reviewed.

Soil and clay stabilization with calcium- and non-calcium-based additives: A state-of-the-art review of challenges, approaches and techniques

This note presents a study of the efficacy of fly ash as an additive in improving the engineering characteristics of expansive soils. An experimental program has evaluated the effect of the fly ash content on the free swell index, swell potential, swelling pressure, plasticity, compaction, strength, and hydraulic conductivity characteristics of expansive soil. The plasticity, hydraulic conductivity and swelling properties of the blends decreased and the dry unit weight and strength increased with an increase in fly ash content. The resistance to penetration of the blends increased significantly with an increase in fly ash content for a given water content. Excellent correlation was obtained between the measured and predicted undrained shear strengths.

Effect of fly ash on engineering properties of expansive soils

An experimental evaluation of the behavior of footings on geosynthetic-reinforced sand

Analytical modeling of geogrid reinforced soil foundation

Results are presented from a series of tests performed to investigate improvement in load-carrying capacity and reduction in bulging of a granular pile in soft clay by geogrid reinforcement. The st...

Compressive load response of granular piles reinforced with geogrids

This paper presents, by way of comparison, the effect of fly ash on the volume change of two different types of clay, one a highly plastic expansive clay and the other a nonexpansive clay, also of high plasticity. Expansive clays swell on absorbing water and shrink on drying. Nonexpansive clays undergo large compression at high water contents. The effect of fly ash content on free swell index, swell potential, and swelling pressure of expansive clays was studied. Compression index and secondary consolidation characteristics of both expansive and nonexpansive clays were also determined. Swell potential and swelling pressure, when determined at constant dry unit weight of the sample (mixture), decreased by nearly 50% and, when determined at constant weight of clay, increased by nearly 60% at 20% fly ash content. Compression index and coefficient of secondary consolidation of both the clays decreased by 40% at 20% fly ash content.

Radhey S. Sharma

Papers

Effect of fly ash on engineering properties of expansive soils

An experimental evaluation of the behavior of footings on geosynthetic-reinforced sand

Analytical modeling of geogrid reinforced soil foundation

Compressive load response of granular piles reinforced with geogrids

Volume Change Behavior of Fly Ash-Stabilized Clays