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Full-Text Articles in Engineering
Evaluating Waste Concrete For The Treatment Of Acid Sulphate Soil Groundwater From Coastal Floodplains, Gyanendra Regmi, Buddhima Indraratna, Long Nghiem, Laura Banasiak
Evaluating Waste Concrete For The Treatment Of Acid Sulphate Soil Groundwater From Coastal Floodplains, Gyanendra Regmi, Buddhima Indraratna, Long Nghiem, Laura Banasiak
Long D Nghiem
The treatment of acidic groundwater generated from acid sulphate soil (ASS) terrain is a challenging environmental issue in coastal floodplains of Australia. In this study, a laboratory column experiment was conducted to assess the performance of waste concrete for treating the acidic groundwater leachate from ASS terrain of the Shoalhaven region of NSW. The groundwater was highly acidic (pH of 2.5–3.5) and contained elevated concentrations of iron (10–90 mg/L) and aluminium (30–45 mg/L). Passage of the acidic groundwater through the column filled with waste concrete resulted in a significant improvement in water quality. Reduction in the concentration of iron and …
A Neural Network Approach To Predict The Performance Of Recycled Concrete Used In Permeable Reactive Barriers For The Treatment Of Acidic Groundwater, B Guruprasad, Buddhima Indraratna, Long Nghiem, G Regmi
A Neural Network Approach To Predict The Performance Of Recycled Concrete Used In Permeable Reactive Barriers For The Treatment Of Acidic Groundwater, B Guruprasad, Buddhima Indraratna, Long Nghiem, G Regmi
Long D Nghiem
This study developed a neural network model for examining the performance of recycled concrete for the treatment of acidic groundwater. Concentrations of Al, Fe and Ca and alkalinity of the effluent were selected as the output parameters to simulate the performance of recycled concrete for neutralizing acidic groundwater. The input variables were the number of pore volumes, pH, oxidation reduction potential and the average hydraulic conductivity. Of the 658 experimental datasets available, 409 datasets were used for training, 184 datasets were used for validation, and the remaining datasets were used for cross-validation. The reported results indicate that the neural model …
Treatment Of Acidic Groundwater In Acid Sulfate Soil Terrain Using Recycled Concrete: Column Experiments, Gyanendra Regmi, Buddhima Indraratna, Long Nghiem, A. Golab, B Guru Prasad
Treatment Of Acidic Groundwater In Acid Sulfate Soil Terrain Using Recycled Concrete: Column Experiments, Gyanendra Regmi, Buddhima Indraratna, Long Nghiem, A. Golab, B Guru Prasad
Long D Nghiem
Acidic groundwater generated from pyrite oxidation in acid sulfate (AS) soil is a major geoenvironmental problem in Australia. This study aims to evaluate recycled concrete as a reactive material in permeable reactive barriers (PRBs) for the remediation of acidic groundwater in low-lying AS soil floodplains. Laboratory experiments were systematically conducted to investigate the acid neutralization behavior of recycled concrete and its potential to remove dissolved Al and Fe. The results confirmed that recycled concrete could effectively treat acidic groundwater from an AS soil terrain, resulting in near neutral effluent over a long period with complete removal of Al and Fe. …
Armouring By Precipitates And The Associated Reduction In Hydraulic Conductivity Of Recycled Concrete Aggregates Used In A Novel Prb For The Treatment Of Acidic Groundwater, Punyama Pathirage, Buddhima Indraratna, Long Duc Nghiem, Laura Banasiak, Gyanendra Regmi
Armouring By Precipitates And The Associated Reduction In Hydraulic Conductivity Of Recycled Concrete Aggregates Used In A Novel Prb For The Treatment Of Acidic Groundwater, Punyama Pathirage, Buddhima Indraratna, Long Duc Nghiem, Laura Banasiak, Gyanendra Regmi
Long D Nghiem
Acidic groundwater generated from acid sulphate soil (ASS) is a major geo-environmental problem in Australia. A permeable reactive barrier (PRB) with recycled concrete aggregates as the reactive material has received considerable attention as an innovative, cost effective technology for passive treatment of acidic groundwater in ASS terrain. Laboratory column experiments conducted at the University of Wollongong investigated the acid neutralisation behaviour of recycled concrete and its potential to remove dissolved aluminium (Al) and iron (Fe). The recycled concrete effectively treated the acidic groundwater, resulting in near-neutral effluent pH and complete removal of Al and Fe. However, armouring of the concrete …
Static Flexural Behaviour Of Fly Ash-Based Geopolymer Composite Beam: An Alternative Railway Sleeper, Wahid Ferdous
Static Flexural Behaviour Of Fly Ash-Based Geopolymer Composite Beam: An Alternative Railway Sleeper, Wahid Ferdous
Wahid Ferdous
These days, the most commonly used materials for railway sleepers are timber, concrete and steel. High maintenance cost, installation issues, deterioration of materials, and environmental considerations are among the factors that prompt research and industry to seek a different and more efficient system. This research was undertaken with the aim of developing a material for sleepers which may overcome some of these problems. Through a comprehensive survey of the literature, it was decided to propose and investigate a sleeper system composed of fly ash-based geopolymer concrete and pultruded FRP profile composites. Although the engineering properties of fly ash-based geopolymer concrete …
Highly Linear, Wide-Dynamic-Range Multiple-Input Translinear Element Networks, Kofi Odame, Eric Mcdonald, Bradley Minch
Highly Linear, Wide-Dynamic-Range Multiple-Input Translinear Element Networks, Kofi Odame, Eric Mcdonald, Bradley Minch
Bradley Minch
In this paper, we propose a modification to the class of circuits known as multiple input translinear element (MITE) networks. Our proposed modification leads to a MITE network that is free from certain nonidealities encountered in previous implementations. Further, the new MITE network described here readily accommodates the use of bipolar junction transistors in the input and output stages, thus implying a significantly wider dynamic range than we can achieve using subthreshold MOSFETs.