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.

Special Issue: Supplementary Cementitious Materials in Concrete, Part I

“…properties of modified cement matrix composites reinforced with fibers [14,[18][19][20]; • application of new types of supplementary cementitious materials [13,16,[21][22][23][24][25][26][27][28]; • characterization of various types of modified cement based materials [18,21,23,[25][26][27][28][29][30][31].…”

“…The issues of the original research papers and stat-of-the art reviews published in this Special Issue of Materials, and coming from over 45 international universities and scientific centres, can be divided as follows: permeability and diffusivity, which are directly related to the quality of concrete and to the durability in various aggressive environments [ 13 , 14 , 15 , 16 , 17 ]; properties of modified cement matrix composites reinforced with fibers [ 14 , 18 , 19 , 20 ]; application of new types of supplementary cementitious materials [ 13 , 16 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ]; characterization of various types of modified cement based materials [ 18 , 21 , 23 , 25 , 26 , 27 , 28 , 29 , 30 , 31 ]. …”

“…application of new types of supplementary cementitious materials [ 13 , 16 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ];…”

“…Vukićević et al [ 24 ] proposed the use of alternative waste materials and hydraulic binders for the soft soil stabilization. High plasticity clay stabilization using fly ash, as well as engineering properties of ash and ash-slag mixtures, were investigated.…”

The Influence of Compaction and Water Conditions on Shear Strength and Friction Resistance between Geotextiles and Ash-Slag Mixture

“…Colliery wastes, mainly medium-grained, are increasingly used in road construction to build embankments [11,36,37], which are stabilized with hydraulic binders [38]. They are also used as materials to stabilize weak soil [39][40][41][42]. However, there is no literature describing the interaction on the contact between the ash-slag mixture and geosynthetics.…”