This paper presents an experimental study on the nature of permeation properties and pore structure of concrete surface layers containing fly ash. Concretes containing different dosages of fly ash as a replacement for cement (15% and 30% by weight of total cement materials, respectively) were investigated. Concrete without any fly ash added was also employed as the reference specimen. Laborator...

A brief overview on boiler tubes ash deposit characterization and thermophysical properties of deposits are given. The structure of an ash deposit on the heat exchange surface of a boiler is usually non-uniform. The thickness of the deposit increases with time and during this process chemical reactions and sintering of ash particles may lead to structural changes. Therefore the thermal conducti...

P. Priyadharshini, G. Mohan Ganesh, A.S. Santhi Abstract— The reduction in moisture of fresh concrete results in plastic shrinkage due to tensile stress induced by capillary pressure. When the tensile strength signs beyond the capacity of concrete, it cracks and this effect in early stage of concrete is termed as plastic shrinkage of concrete. This becomes a serious issue for large surface area...

BACKGROUND Mount Etna, located in the eastern part of Sicily (Italy), is the highest and most active volcano in Europe. During the sustained eruption that occurred in October-November 2002 huge amounts of volcanic ash fell on a densely populated area south-east of Mount Etna in Catania province. The volcanic ash fall caused extensive damage to infrastructure utilities and distress in the expose...

On April 14, 2010, when meltwaters from the Eyjafjallajökull glacier mixed with hot magma, an explosive eruption sent unusually fine-grained ash into the jet stream. It quickly dispersed over Europe. Previous airplane encounters with ash resulted in sandblasted windows and particles melted inside jet engines, causing them to fail. Therefore, air traffic was grounded for several days. Concerns a...

The coal utilization in thermal power plants in Malaysia has increased significantly which produces an enormous amount of coal combustion by-product (CCBP) or coal ash and poses severe disposal problem. As each coal ash is distinct, this study presents the geochemistry of the coal ash, in particular fly ash, produced from the combustion of local coal from Kuching Sarawak, Malaysia. The geochemi...

Oxidative stress (OS) impact on a single neuron's function in vivo remains obscure. Using C. elegans as a model organism, we report the effect of paraquat (PQ)-induced OS on wild type worms on the function of the ASH polymodal neuron. By calcium (Ca2+) imaging, we quantified ASH activation upon stimulus delivery. PQ-treated worms displayed higher maximum depolarization (peak of the Ca2+ transie...

Chloride content is a critical problem for the reuse of incineration bottom ash as raw material in cement. The effect of dechlorination procedure largely depends on the existence form of the chlorides. However, limited information about the distribution and identity of chlorides in bottom ash can be obtained by bulk analysis methods. In this paper, the investigation towards a more comprehensive...

Decontamination of the radioactive cesium that is widely dispersed owing to a nuclear power station accident and concentrated in fly ash requires an effective elimination system. Radioactive fly ash contains large amounts of water-soluble cesium that can cause severe secondary contamination and represents a serious health risk, yet its complete removal is complicated and difficult. Here it is s...

A study was conducted to evaluate the leaching potential of unpaved road materials (URM) mixed with lime activated high carbon fly ashes and to evaluate groundwater impacts of barium, boron, copper, and zinc leaching. This objective was met by a combination of batch water leach tests, column leach tests, and computer modeling. The laboratory tests were conducted on soil alone, fly ash alone, an...