Roshazita Che Amat

Utilization of Recycled Glass Waste as Partial Replacement of Fine Aggregate in Concrete Production

Glass dust waste creates chronic environmental problems, mainly due to the inconsistency of waste glass streams. Glass is widely used in our lives through manufactured products such as sheet glass, bottles, glassware, and vacuum tubing. Glass is an ideal material for recycling. The use of recycled glass helps in energy saving. The increasing awareness of glass recycling speeds up inspections on the use of waste glass with different forms in various fields. One of its significant contributions is to the construction field where the waste glass was reused for concrete production. The properties of concretes containing glass dust waste as fine aggregate were investigated in this study. Glass dust waste was used as a partial replacement for sand at 10%, 20% and 50% of concrete mixes. Compression strength for 7, 14 and 28 days concrete of age were compared with those of concrete made with natural fine aggregates. The results proved that highest strength activity given by glass dust waste after 28 days. The compressive strength of specimens with 10% glass dust waste content were 32.9373 MPa, higher than the concrete control specimen at 28 days. Using glass dust waste in concrete is an interesting possibility for economy on waste disposal sites and conservation of natural resources.

Use of plastic waste (high density polyethylene) in concrete mixture as aggregate replacement

Rapid industrial development causes serious problem all over the world such as depletion of natural aggregates and creates enormous amount of waste material from construction and demolition activities. Quantities of polymer wastes also have been increased these recent years due to the boost in industrialization and the rapid improvement in the standard of living. In Malaysia, most of polymer wastes is abandoned and not recycled. This situation causes serious problems such as wastage of natural resources and environmental pollution. Polymer products such as synthetic fibers, plastics and rubber belong to petrochemical compound and not easily biodegradable even after a long period. One of the ways to reduce this problem is to utilize waste materials in the production of concrete. Use of these materials not only helps in getting them utilize in cement, sand, aggregate, concrete and other construction materials, it helps in reducing the cost of concrete manufacturing, but also has numerous indirect benefits such as reduction in land-fill cost, saving in energy and protecting the environment from possible pollution effects. An experimental research is made on the utilization of plastic waste, High Density Polyethylene (HDPE) as coarse aggregates in concrete with a percentage replacement of 10 %, 20 % and 30 %. The laboratory tests include slump test, compressive strength and water absorption were conducted in this research. The samples content 10 % of HDPE has better performance in term of strength.

Compressive Strength of Concrete from Lightweight Bubbles Aggregate

Compressive strength of concrete is the major mechanical properties of concrete that need to be focused on. Poor compressive strength will lead to low susceptibility of concrete structure towards designated actions. Many researches have been conducted to enhance the compressive strength of concrete by incorporating new materials in the concrete mixture. The dependencies towards natural resources can be reduced. Therefore, this paper presents the results of an experimental study concerning the incorporation of artificial lightweight bubbles aggregate (LBA) into cementations mixture in order to produce comparable compressive strength but at a lower densities. Three concrete mixtures containing various percentages of LBA, (10% - 50% of LBA) and one mixture used normal aggregate (NA) were prepared and characterized. The compressive strength of LBA in concrete was identified to be ranged between 39 MPa and 54 MPa. Meanwhile, the densities vary between 2000 kg/m3 to 2300 kg/m3.

Properties of Lightweight Concrete Composites with Mixture of Fly Ash and Concrete Sludge Aggregate

Lightweight foamed concrete is a concrete made by cement slurry mixed with foam so that foamed concrete that is much lighter than conventional concrete can be produced. The objectives of this study is to develop optimal pre-foamed lightweight foamed concrete and to achieve desired density of lightweight concrete that is below 2400 kg/m3. Three samples of concrete were batching with 0%, 25% and 50% of foam respectively under mixing ratio of 1:1:2 and foam dilution ratio 1:5 to obtain optimum result. Based on the result attained, the samples achieved the bulk density ranged from 1943 kg/m3 to 2305 kg/m3. In addition, other physical characteristics of this mixture of materials show that its water absorption for all the samples was increased from 6.508% to 11.889%. This trend of results was obtained if the volume of foam presented in the concrete were increased. Furthermore, the samples achieved compression strength ranged from 22.418 MPa to 32.229 MPa with presence of foam. In summary, with additional of fly ash and concrete sludge as aggregate it can help to produce comparable concrete composites with lighter density.

Performance of Lightweight Foamed Concrete with Replacement of Concrete Sludge Aggregate as Coarse Aggregate

The use of waste materials in construction industry is very essential in order to reduce the depletion of natural sources. Thus, this study is focused to determine the performance of lightweight foamed concrete made with concrete sludge aggregate (CSA) and to determine the optimum proportion of CSA that can gives optimum compressive strength. Strength is one of the most important properties of concrete since the first consideration in structural design is that the structural elements must be capable of carrying necessary loads. CSA has been use as partial substitution to normal coarse aggregate to manufacture structural lightweight foamed concrete. Two different sets of CSA proportion have been prepared with foamed injected through mixing processes. 25% and 50% of CSA for production of lightweight concrete were designed according to proper mix design. It is found that maximum percentage of CSA that contribute to the highest compressive strength of 25MPa is 50% of CSA replacement. Its density is 1837 kg/m3 with water adsorption of 16.35%. The usage of concrete sludge aggregate as construction material can be further promoted in order to solve major environmental issues.

Properties of Lightweight Bubbles Aggregate (LBA) for the Replacement of Coarse Aggregates in Concrete

The depletion of natural resources in the production of coarse aggregate are very crucial. Construction materials are solely depends on natural granite in the making of cement composite. Therefore , there is an urgency need to develop new alternatives material that can replace the usage of granite in concrete production. In this study, LBA have been produced to cater this problem. It is made from a mixture of bubbles from foam and ordinary portland cement. The ratio of the raw materials used is 1 part of bubbles and 2 part of ordinary Portland cement. Its manufacturing process does not involving any sintering process so it will part help to reduce energy comsuption at about 30%. The properties and characteristics of the LBA such as density, specific gravity, water absorption, strength were investigated. Results shown that the specific gravity of LBA was 1.00, water absorption was 19.44%, dry bulk density was between 730 – 800 kg/m3 and dry loose bulk density was ranged from 700 to 730 kg/m3 and the strength of aggregates is 14.00 MPa. It is found that the LBA can be used as a partial replacement of granite in the production of concrete. Keywords: LBA, concrete, density

The Utilization of Aluminum Waste as Sand Replacement in Concrete

Development activities in construction sector have caused serious problems throughout the world as the natural resource depletion and produce large amounts of waste. In Malaysia, the main problem appeared when most of the waste was abandoned and not recycling. Such conditions can cause serious problem such as environmental pollution. This research utilizes aluminum waste as sand replacement in concrete. The use of these materials not only helps in the natural resources such as sand, aggregate, cement and other building. However, it also helps in reducing the manufacturing cost of the concrete. In addition, the reduction in the cost of waste disposal, saving manpower and protect the environment from the effects of pollution are the benefits derived from the use of waste materials. A study was conducted on the use of recyclable aluminum materials, as sand replacement material in concrete mix with replacement of 1%, 2% and 5%. Lab tests, including slump tests, compressive strength and water absorption were conducted in this study. As a result, samples containing 1% aluminum waste has better performance in terms of strength and containing 5% aluminum waste has good resistance to water absorption. Using aluminum waste in concrete is an interesting way in recycling waste thus can reduce waste disposal on sites and also can conserve the natural resources.

A Study on Hydrogen Sulphide as Potential Tracer in Landfill Gas Monitoring

Municipal solid waste (MSW) landfills are one of the major source of hydrogen sulphide (H2S) which is the offensive odours potentially creating annoyance in adjacent communities. This project focuses on H2S emission from landfills in Perlis, Malaysia. Landfill gas (LFG) samples were collected and analyzed accordance with NIOSH method 6013. The mean concentrations of H2S in Kuala Perlis Landfill and Padang Siding Landfill are 210.68 ppm and 242.85 ppm respectively. High concentrations of H2S may be a concern for employees working on the landfill site. These results indicate that workers should use proper personal protection at landfill when involved in excavation, landfill gas collection, and refuse compaction. The formation of H2S most likely to be contributed by the biological conversion of sulfate from gypsum-rich soils and landfill wastewater treatment sludges by sulfate-reducing bacteria (SRB) which can utilize dissolved sulfate as an electron acceptor. H2S is conveniently detected by hand held analyzer, such Jerome meter, landfill gas analyzer. In the organic range, in the ease of detection range in the dispersion rate within the landfill site, the monitored H2S gas form a very noticeable concentration with the travelling wind direction. It proved that the dispersion rate of H2S are suitable as tracer to detect route of travelling in a certain distance.

Characterization of Rambutan Seed (Nephelium lappaceum) as Natural Adsorbent for Wastewater Treatment

Activated carbons were prepared from rambutan seed with impregnation of zinc chloride as dehydrating agent. In order to find its characteristics, different zinc chloride to rambutan seed ratio (0.5 and 2) and activation temperature (450 and 650 °C) was employed. The carbonization occurred in a tube furnace with flow of nitrogen gas at 0.5 L/min. The results showed that at higher impregnation ratio and carbonization temperature produced a wider BET surface area of activated carbon that was 9.8761 m2/g. Total pore volume also increased with increases of these two factors. However activation yield was decreased with increasing of carbonization temperature.