The production of lightweight aggregates from pulverised fuel ash as the main material
| dc.contributor.author | Ismail, Khairul Nizar | |
| dc.date.accessioned | 2014-11-03T02:27:01Z | |
| dc.date.available | 2014-11-03T02:27:01Z | |
| dc.date.issued | 2006 | |
| dc.description | PhD | en_US |
| dc.description.abstract | The present study covers the production of lightweight aggregates using pulverized fuel ash. The main aim of this research was to produce lightweight aggregates which can be used as replacement for normal (natural) aggregates in structural concrete. Pulverised fuel ash was the main raw material used in this study and among the wastes which can cause disposal and environmental degradation problems. Lightweight aggregates produced from pulverised fuel ash, will have low density, high strength and it will reduce the dead weight and material handling costs for construction work. The production processes of lightweight aggregate from pulverised fuel ash involved grinding, mixing of raw materials, agglomeration and sintering process for hardening and binding of the particles. It also involved study on the physical, mechanical and chemical properties of raw materials such as pulverized fuel ash, expanded clay, quarry dust and rice husk ash. Quarry dust, clay and rice husk ash were also used as additional raw materials in this process. The effect of sintering at temperatures between 1180 0C and 1250 0C on density, apparent porosity, percent of water absorption, mineralogy and microstructure of lightweight aggregates was examined. The samples were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF) and the morphology was examined by scanning electron microscope (SEM). Chemical analysis showed that pulverized fuel ash used, was F class with an average particle size of 6.92 μm. It contained siliceous glass phase together with the crystalline quartz phase, hematite and mullite. The best lightweight aggregates obtained from this study consisted of 50 % pulverized fuel ash, 30 % rice husk ash, 10% quarry dust and 10 % expanded clay (PQR 1) and was used for further study. Result obtained showed that at the sintering temperature of 1230oC, the lightweight aggregate PQR 1 had particle bulk density of 1.388 g/cm3 and loose bulk density of 990 kg/m3 for coarse aggregates. The 24 hours water absorption for aggregate PQR 1 was 0.24 % and contained 27.15 % porosity. Based on the XRD result, it was found that the graphite phase that contained carbon was absent and had decomposed as carbon dioxide gas. This result was further supported by the microstructure of the aggregate which showed the existence of voids in the cross section of the aggregate with increasing sintering temperature. This result has satisfied the specification of British Standard BS 3797, Part 2 (1976) for lightweight aggregate. Lightweight concrete using the lightweight aggregates PQR 1 was produced and the compressive strength, density and microstructure of the lightweight aggregate concrete were studied up to 28 days. The average 28-day compressive strength was recorded as 30.5 N/mm2 (30 MPa) while, the average density was 1867.56 kg/m3. | en_US |
| dc.identifier.uri | http://hdl.handle.net/123456789/309 | |
| dc.language.iso | en | en_US |
| dc.subject | Materials and Mineral Resources Engineering | en_US |
| dc.subject | Fuel ash | en_US |
| dc.title | The production of lightweight aggregates from pulverised fuel ash as the main material | en_US |
| dc.type | Thesis | en_US |
Files
License bundle
1 - 1 of 1
Loading...
- Name:
- license.txt
- Size:
- 1.71 KB
- Format:
- Item-specific license agreed upon to submission
- Description: