Advanced Materials Research Vol. 701

Abstract: Effects of partial replacements of sand by waste crumb rubber 1 mm particle size on the performance of reinforced concrete under low velocity impact loading were investigated. Specimens were prepared for 5%, 10% and 20 % replacements by volume of sand. All specimens were cured in moist air for 90 days. For each case, six beams of 100 mm ×100 mm × 500mm were subjected to 5.15 kg hammer from 900mm height. The number of blows of the hammer required to induce the first crack of the beam were recorded. The results are presented in terms of impact energy required for the first crack. The crumb rubbers increased the impact energy for first crack.

Abstract: 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.

Abstract: This paper presents the potential of utilizing used cooking oil as a foaming agent in the production of lightweight concrete. This morphology study is to observe the development of Fuscof as foam agent in lightweight greencrete after ambient curing process. Foam formulated was produced derived by utilization the waste of used cooking oil. The mortar phase of FUSCOF lightweight greencrete was formed. Then, the material morphology of the lightweight greencrete was analysis by using FESEM. The morphology of FUSCOF greecrete was then compared with a lightweight foam produced from commercial synthetic foam agent. The water cement ration has been determined for this mix design is 0.6. The density of FUSCOF lightweight greencrete was 1200. The age of the ambient curing process was varied between ±30-day and ±60-day. The maturation of the mortar was observed. As a result, the major element was Calcium, Ca has been detected by EDAX.

Abstract: Waste paper sludge ash (WPSA) is a byproduct and problematic waste of paper industries. The investigation was driven by the increasing demand for reuse options in paper-recycling industry. This paper present on the morphology and physical analysis studies on polymerization of WPSA mortar. Two (2) types of polymeric mortar mixes containing WPSA with alkaline activators and without alkaline activators were prepared. The morphology of each mixes was determined using Spectra Electron Microscope (SEM) and the physical test is focus on compressive strength. However, the element diffraction of each mixes using Energy Dispersive X-Ray Spectroscopy (EDX) was also carried out as a method to identify the polymerization of polymeric mortar. From the result obtained it is found that the utilization of WPSA reduced the polymerization of polymeric mortar due to more pores. From the EDX analysis it is also revealed that the WPSA polymeric mortar also contained less synthetic aluminous silicate compound. However, the strength gain up to 6MPa and it is comparable with other high calcium material mortar.

Abstract: Urbanization in many cities needs to adopt modern and innovative techniques in the construction industry to balance the supply and demand in housing issues. To address the issue, there is a need to look for alternative solutions and provide affordable quality housing. Therefore, innovative construction method such as Industrialized Building System (IBS) needs to be adopted to move away from conventional building construction technique in order to meet the demand. Precast Sandwich panel is one of the alternative IBS that could meet and fulfil this target. Previous research had shown that this panel had a potential to provide possible solution to housing problems especially in low and medium cost housing sector. This paper presents findings from previous research in this field especially on the panel's materials properties, structural behaviours and empirical expression to determine its ultimate load carrying capacity. It is hoped the overview on this topic could be used as guidance for future research on developing a lightweight sandwich panel system in low to medium rise building.

Abstract: Effects of partial replacements of sand by waste fine crumb rubber on the performance of reinforced concrete under low velocity impact loading were investigated. Specimens were prepared for 5%, 10% and 20 % replacements by volume of sand. All specimens were cured in moist air for 90 days. For each case, six beams of 100 mm ×100 mm × 500mm were subjected to 5.15 kg hammer from 900mm height. The number of blows of the hammer required to induce the first visible crack of the beam were recorded. The results are presented in terms of impact energy required for the first crack. The fine crumb rubbers increased the impact energy for first crack.

Abstract: An innovative technique in producing cement syntactic foam (CSF) was proposed in this investigation. This cellular composite material basically consists of a cement matrix embedded with in-house developed cement hollow spheres (CHS). The produced foams incorporated with CHS having different wall thickness, were characterized for compressive strength and then compared with that of plain cement. It was observed that the CSFs were 37%-55% lighter than the plain cement but possessed compromised compressive strength. The comparative compressive properties of CSFs were also evaluated and reported. It was found that the CSF incorporated with thicker-coated CHS showed higher compressive strength compared to that of incorporated with thinner-coated CHS. The failure patterns within the test samples were also examined to determine the failure mechanism. These observations showed that both CSFs exhibited shearing type failure but exhibit different types of crack fractures due to the difference in CHS wall thickness.

Abstract: This paper discusses the effect of fineness of fly ash on powder packing density, compacting voidage, paste fluidity and compressive strength. The results showed that when the content of fly ash is between 0%~40%, the compacting voidage of the composite powder is reduced by adding the fly ash with D50 1.0μm and 3.0μm, not by the fly ash with D50 12.0μm. The results of pressured entities voidage are consistent with the calculated values by Aim-Goff model. The optimal content of fly ash with D50 1.0μm and 3.0μm are 30% and 25% respectively, which is more helpful to improve the dense packing density of composite powder. There are good corresponding relationships between compacting voidage, dense packing density and fluidity in composite powder or paste by adding the fly ash with D50 1.0μm and 3.0μm, the fly ash can reduce the dense packing voidage of composite powder, and improve the fluidity of fresh paste.

Abstract: Plasma treatment of activated carbon (AC) was found to be an efficient method to enhance phenol removal by ozonation in a three-phase fluidized-bed reactor. The plasma treatment extended porous structure, changed surface morphologies, and produced oxygen functional groups on the surface of AC. Plasma-treated activated carbon together with O3 gave the best removal result, in which phenol was completely decomposed within 10 min (with pseudo first-order rate constant k = 0.286 min1), while untreated AC without O3 showed the worst result (k = 0.024 min1). Consequently, AC modified by plasma was shown to be a good material for removal of organic pollutants and yield superb performance in an integrated process with ozone in a fluidized-bed reactor.

Abstract: Organic soil is always known as problematic soil because of its engineering properties are inferior from other soft soils and/or because its behaviour may deviate from traditional rules of soil behaviour which makes it difficult to predict and design. Considerable research has been carried out over the years on organic soils, particularly peat soil which consists of various components of organic matter but the effect of particular organic matter is less reported. Hence, this study is carried out to determine the effect of humic acid (a kind of humified organic matter) on kaolin (which is widely studied). This paper addresses the influence of humic acid (30% and 50% of dry mass) on kaolins geochemistry properties namely Atterberg limits, compaction, specific gravity and Loss on Ignition (LOI). The findings of the study showed that the contents of humic acid had altered the behaviour of kaolin. The loss on ignition increased linearly with the increment of humic acid. However, the specific gravity, maximum dry density and Atterberg limits decreased with addition of humic acid. Atterberg limits decreased as the humic acid increased is believed to be due to the nature of humic acid which precipitated under acidic environment.