Bioengineering Techniques for Soil Erosion Protection and Slope Stabilization

The use of bio-engineering methods for soil erosion protection and slope stabilization has a long tradition. Old methods with rocks and plants, structures of timber have been used over the past centuries. Recently these old soil conservation and stabilization techniques have been rediscovered and improved. Biotechnical engineering methods have become part of geotechnical and hydraulic engineering and have helped bridge the gap between classical engineering disciplines, land use management, landscape architecture and biological sciences. In this paper the different uses of plants in hydraulic and geotechnical engineering design are presented. The core of this study is a comprehensive overview of the most important biotechnical construction methods used for soil erosion protection and slope stabilization. Methods, construction procedure, and the major advantages and disadvantages of these biotechnical methods are discussed. Considerations about construction and maintenance costs conclude in this paper.

Soil compaction of peat under the influence of electrokinetic stabilization (EKS) treatment

This study aims to enhance the properties of peat such as, (shear strength, compressibility, permeability and liquid limit). Peat is considered as one of the problematic soil in construction projects all over the world, which covers about 4% land of the whole world while 8% of the total area of Malaysia and about (5.86%) of peat soil existing in Johor state. Low shear strength of peat may lead to massive loss of various sectors contributing toward any economic activities such as construction & agriculture projects. There are several issues related to peat stabilization which has become a priority to ensure that soft soil is stable & capable of supporting a load after treated by a suitable soil stabilization method. The problem can be finally reduced by applying stabilization treatment to enhance its properties. One of the known technique Electrokinetic Stabilization treatment, by applying an electric potential to stabilize soft soil. In this method, aluminum was used as an electrode with various voltage potential in the range of 110 to 150 V was applied on both cathode and anode electrode for the duration of 3 and 6 hours at the testing condition without & with a load of (50 kg). Soil parameters such as, shear strength

Use of Recycled Crushed Concrete (RCC) Fines for Potential Soil Stabilization

This study evaluated the use of Recycled Crushed Concrete (RCC) Fines for potential soil stabilization. Soil stabilization is the enhancement of subgrade stability to improve the constructability of successive pavement layers. Use of RCC fines may not only provide less costly alternatives for subgrade stabilization, but their use may also alleviate landfill disposal challenges

Olivine for soil stabilization

The aim of this paper is to review the potential capability of olivine as a new binder for soil stabilization. The recent research shows that using environmental friendly materials for soil stabilization is expanding. The increasing amount of greenhouse gasses (GHG) such as CO2 has also instigated research into finding environmentally friendly materials for soil stabilization. For quite some time, cement is one of the well-known binders in soil stabilization, but it releases high amount of CO2, and energy consumption of cement have caused civil engineers to use some other materials or by-products to fully or partially replace cement for soil stabilization. Recently, alkaline activation process in soil stabilization is an interesting option at medium-term to fully eliminate traditional cementitious binders such as cement and lime. Olivine is a well-known material for CO2 sequestration. Furthermore, the high amount of SiO2, Al2O3 and Fe2O3 in olivine could classify this mineral as a pozzolanic material in soil stabilization

Improving Wildflower Longevity in Roadside Seeding Areas

Re-vegetation efforts on bare roadsides of newly-constructed highways are primarily focused on the stabilization of soil to reduce rates of erosion. The Nebraska Department of Transportation (NDOT) seeds roadsides with a diverse mixture of grasses and wildflowers for site stabilization as well as to enhance the visual quality of roadsides. Although grasses dominate roadside plantings in terms of cover and density, wildflowers are largely responsible for the visual enhancement of recently-seeded roadsides. In addition to the visual component, wildflowers provide essential ecological functions on roadsides. Wildflowers improve water and nutrient cycling in the compacted roadside soils by increasing water infiltration and nutrient availability. Leguminous wildflower species increase nitrogen content of soil. The variability of wildflower leaf size, shape and orientation provides a more continuous soil cover than grass alone. The diversity of wildflower growth habits and life cycles also allows for a greater range of stand establishment and persistence when compared to sites seeded to grasses alone. This article presents strategies for increasing wildflower success in roadside plantings

Soil Stabilization Manual 2014 Update

Soil Stabilization is used for a variety of activities including temporary wearing curses, working platforms, improving poor subgrade materials, upgrading marginal materials, dust control, and recycling old roads containing marginal materials. There are a number methods of stabilizing soils including modifying the gradation, the use of asphalt or cement stabilizers, geofiber stabilization and chemical stabilization. Selection of the method depends on the soil type, environment and application. This manual provide tools and guidance in the selection of the proper stabilization method and information on how to apply the method. A major portion of this manual is devoted to the use of stabilizing agents. The methods described here are considered best practices for Alaska.State of Alaska, Alaska Dept. of Transportation and Public Facilitie

Interactive effect of soil pore network structure and substrate quality on soil CO2 production: a combined X-ray CT incubation experiment

The role of soil structure in organic matter (OM) stabilization has been primarily investigated through physical fractionation studies operative at the scale of aggregates and smaller organo-mineral particles. By narrowing down soil structure to an arrangement of mineral and organic particles, the majority of studies did not explore the spatial organization of the soil pore network, the actual habitat of microorganisms. In a lab experiment we incubated a sandy loam soil (with application of ground grass or sawdust) in 18 small aluminum rings (Ø 1 cm, h 1 cm). Bulk density was adjusted to 1.1 or 1.3 Mg m-3 (compaction) and 6 rings were filled at a coarser Coarse Sand:Fine Sand:Silt+Clay ratio

Parallel Splitting and Decomposition Method for Computations of Heat Distribution in Permafrost

A mathematical model, numerical algorithm and program code for simulation and long-term forecasting of changes in permafrost as a result of operation of a multiple well pad of northern oil and gas field are presented. In the model the most significant climatic and physical factors are taken into account such as solar radiation, determined by specific geographical location, heterogeneous structure of frozen soil, thermal stabilization of soil, possible insulation of the objects, seasonal fluctuations in air temperature, and freezing and thawing of the upper soil layer. A parallel algorithm of decomposition with splitting by spatial variables is presented

nZVI particles production for the remediation of soil and water polluted by inorganic Lead

The present study deals with experiments of Pb removal by nano-Zero Valent Iron (nZVI) in aqueous solution and in soil. Synthetic Pb aqueous solutions were treated by nZVI, at a fixed Pb concentration of 100 mg L-1 , varying nanoparticles initial concentration in the range between 27 and 270 mg nZVI L-1 . A kinetic study was carried out: Pb adsorption followed a first order kinetic, and half life times between 11 and 26.66 min were determined. Soil samples were first characterized, and Pb speciation and concentration by sequential extractions was determined. Adsorption tests were then carried out at three selected amounts of nZVI, to allow Pb stabilization in the soil matrix. To evaluate the treatment efficiency, sequential extractions were also performed on the treated samples