This thesis presents a study of the characterisation of fine aggregates manufactured from waste quarry material and their use in concrete supported by artificial neural network models of the fresh and hardened concrete properties. The reutilization of rock filler, a by-product of the sand manufacturing process, as a soil liming material is explored. A set of tests and techniques were identified to characterise fine aggregates manufactured from quarry dusts via a dry processing system. Granite, limestone, sandstone and basalt manufactured sands and their unprocessed counterparts “feed quarry dusts” were characterised with respect to their shape and texture, grading and quality of fines (presence of clays). The results showed that the reprocessing of quarry dusts improves the particle shape and grading irrespective of rock mineralogy. Plasticised and non-plasticised concrete mixes were developed and the fresh and hardened properties tested. Concrete consistency, compressive and flexural strength is correlated with the fine aggregate characterisation test results. The manufactured fine aggregates showed a higher water demand when compared with natural sand whereas compressive and flexural strengths were enhanced. Artificial neural network models were developed to enable the prediction of the consistency and compressive strength of concrete. These models used the fine aggregate properties and mix composition parameters as input variables and were validated using a separate testing dataset, additional concrete mixes and numerical evaluation. Artificial neural network models were shown to be able to predict fresh and hardened concrete properties based on the fine aggregate characteristics. The excess fillers created in the sand manufacturing process were evaluated for soil liming potential through standard tests and a soil incubation study. The main finding was that materials with high silicate content exhibit a potential for liming, however, a higher dosage is required when compared to the dosage of high purity limestone to achieve the same liming potential.
Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:629834 |
Date | January 2014 |
Creators | Pilegis, Martins |
Publisher | Cardiff University |
Source Sets | Ethos UK |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
Source | http://orca.cf.ac.uk/66215/ |
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