The Experts below are selected from a list of 9345 Experts worldwide ranked by ideXlab platform

Y Sano - One of the best experts on this subject based on the ideXlab platform.

  • MSW fly ash stabilized with coal ash for Geotechnical Application.
    Journal of hazardous materials, 2000
    Co-Authors: M Kamon, T Katsumi, Y Sano
    Abstract:

    The solidification and stabilization of municipal solid waste (MSW) fly ash for the purpose of minimizing the geo-environmental impact caused by toxic heavy metals as well as ensuring engineering safety (strength and soaking durability) are experimentally evaluated. The mixtures of MSW fly ash stabilized with cement and fluidized bed combustion coal fly ash (FCA) were used for unconfined compressive strength tests, leachate tests, and soaking tests. The behavior of soluble salts contained in the MSW fly ash significantly affects strength development, soaking durability, and the hardening reaction of the stabilized MSW fly ash mixtures. The cement stabilization of the MSW fly ash does not have enough effect on strength development and soaking durability. The addition of cement only contributes to the containment of heavy metals due to the high level of alkalinity. When using FCA as a stabilizing agent for MSW fly ash, the mixture exhibits high strength and durability. However, the Cd leachate cannot be prevented in the early stages of curing. Using a combination of cement and FCA as a MSW fly ash stabilizer can attain high strength, high soaking durability, and the containment of heavy metals. The stabilized MSW fly ash with cement and FCA can be practically applied to embankments.

M Kamon - One of the best experts on this subject based on the ideXlab platform.

  • MSW fly ash stabilized with coal ash for Geotechnical Application.
    Journal of hazardous materials, 2000
    Co-Authors: M Kamon, T Katsumi, Y Sano
    Abstract:

    The solidification and stabilization of municipal solid waste (MSW) fly ash for the purpose of minimizing the geo-environmental impact caused by toxic heavy metals as well as ensuring engineering safety (strength and soaking durability) are experimentally evaluated. The mixtures of MSW fly ash stabilized with cement and fluidized bed combustion coal fly ash (FCA) were used for unconfined compressive strength tests, leachate tests, and soaking tests. The behavior of soluble salts contained in the MSW fly ash significantly affects strength development, soaking durability, and the hardening reaction of the stabilized MSW fly ash mixtures. The cement stabilization of the MSW fly ash does not have enough effect on strength development and soaking durability. The addition of cement only contributes to the containment of heavy metals due to the high level of alkalinity. When using FCA as a stabilizing agent for MSW fly ash, the mixture exhibits high strength and durability. However, the Cd leachate cannot be prevented in the early stages of curing. Using a combination of cement and FCA as a MSW fly ash stabilizer can attain high strength, high soaking durability, and the containment of heavy metals. The stabilized MSW fly ash with cement and FCA can be practically applied to embankments.

T Katsumi - One of the best experts on this subject based on the ideXlab platform.

  • MSW fly ash stabilized with coal ash for Geotechnical Application.
    Journal of hazardous materials, 2000
    Co-Authors: M Kamon, T Katsumi, Y Sano
    Abstract:

    The solidification and stabilization of municipal solid waste (MSW) fly ash for the purpose of minimizing the geo-environmental impact caused by toxic heavy metals as well as ensuring engineering safety (strength and soaking durability) are experimentally evaluated. The mixtures of MSW fly ash stabilized with cement and fluidized bed combustion coal fly ash (FCA) were used for unconfined compressive strength tests, leachate tests, and soaking tests. The behavior of soluble salts contained in the MSW fly ash significantly affects strength development, soaking durability, and the hardening reaction of the stabilized MSW fly ash mixtures. The cement stabilization of the MSW fly ash does not have enough effect on strength development and soaking durability. The addition of cement only contributes to the containment of heavy metals due to the high level of alkalinity. When using FCA as a stabilizing agent for MSW fly ash, the mixture exhibits high strength and durability. However, the Cd leachate cannot be prevented in the early stages of curing. Using a combination of cement and FCA as a MSW fly ash stabilizer can attain high strength, high soaking durability, and the containment of heavy metals. The stabilized MSW fly ash with cement and FCA can be practically applied to embankments.

Zhen Chen - One of the best experts on this subject based on the ideXlab platform.

  • development of an implicit material point method for Geotechnical Applications
    Computers and Geotechnics, 2016
    Co-Authors: Bin Wang, P J Vardon, Michael A Hicks, Zhen Chen
    Abstract:

    Abstract An implicit material point method (MPM), a variant of the finite element method (FEM), is presented in this paper. The key feature of MPM is that the spatial discretisation uses a set of material points, which are allowed to move freely through the background mesh. All history-dependent variables are tracked on the material points and these material points are used as integration points similar to the Gaussian points. A mapping and re-mapping algorithm is employed, to allow the state variables and other information to be mapped back and forth between the material points and background mesh nodes during an analysis. In contrast to an explicit time integration scheme utilised by most researchers, an implicit time integration scheme has been utilised here. The advantages of such an approach are twofold: firstly, it addresses the limitation of the time step size inherent in explicit integration schemes, thereby potentially saving significant computational costs for certain types of problems; secondly, it enables an improved algorithm accuracy, which is important for some constitutive behaviours, such as elasto-plasticity. The main purpose of this paper is to provide a unified MPM framework, in which both quasi-static and dynamic analyses can be solved, and to demonstrate the model behaviour. The implementation closely follows standard FEM approaches, where possible, to allow easy conversion of other FEM codes. Newton’s method is used to solve the equation of motion for both cases, while the formation of the mass matrix and the required updating of the kinematic variables are unique to the dynamic analysis. Comparisons with an Updated Lagrangian FEM and an explicit MPM code are made with respect to the algorithmic accuracy and time step size in a couple of representative examples, which helps to illustrate the relative performance and advantages of the implicit MPM. A Geotechnical Application is then considered, illustrating the capabilities of the proposed method when applied in the Geotechnical field.

Ata G Doven - One of the best experts on this subject based on the ideXlab platform.

  • utilization of fly ash by pelletization process theory Application areas and research results
    Resources Conservation and Recycling, 2000
    Co-Authors: Gokhan Baykal, Ata G Doven
    Abstract:

    Abstract Although pelletization process is a world wide known technique in the production of artificial aggregates, it has not been widely used in construction sector. The 1985 figures show that overall pellet production for use as metallurgical product was 435 million tons and with respect to statistical figures that belong to 1989 the agglomerated product use in construction sector as lightweight aggregate was only 1.2 million tons. The reasons of low utilization of coal combustion by-products as lightweight aggregates in the construction sector are: — the availability of natural resource products and relatively higher costs of agglomeration process due to initial investments and — energy requiring curing procedures to obtain adequate strength for construction Applications (e.g. steam curing and sintering). However, depending on the agglomerated materials’ properties and process efficiency, artificial aggregates with adequate engineering performance may be produced by moisture treatment under atmospheric conditions. In this study, the engineering performance of moist cured fly ash pellets including the effect of lime and cement additions both for Geotechnical Application and concrete production purposes were investigated and the results obtained are quite satisfactory for the related design requirements.