Josef Hadipramana

Contribution of RHA granules as filler to improve the impact resistance of foamed concrete

Foamed concrete as aerated concrete widely used in range of constructions application, no exception to structure shield. As structure shield is important to resist on impact loading. Whilst, Rice Husk Ash (RHA) as agro-waste potentials as filler for foamed concrete. RHA that is produced by uncontrolled burning under 700oC during ± 6 hours obtain the granules contain the carbon and porous. The granules of RHA may fill the porous in matrix foamed concrete without remove the characteristic the foamed concrete its self-as aerated concrete. This investigation RHA has been used as a replacement for fine aggregate. Target density 1800 kg/m3 of foamed concrete both of with and without RHA have been produced to compare their strength and characteristic of impact resistance. SEM and EDS test has been conducted to determine microstructure and chemical composition of foamed concrete with RHA. The results showed that granules of RHA filled the porous and bonded with the denser part into matrix. The presence of granules of RHA has been changing the role of the air cell of porous in foamed concrete when it was subjected to impact loading. Also the granules of RHA give the foamed concrete denser without losing its characteristic of porous entirely.

Effect of Uncontrolled Burning Rice Husk Ash in Foamed Concrete

Recently, foamed concrete has become a popular construction material that can be used in wide range of constructions application. Whilst the Rice Husk Ash (RHA) as agro-waste is contain high amount of silicon dioxide. RHA is produced in significant amount every year from agriculture countries. RHA has potential as a material to produce foamed concrete. In this research RHA has been used as a replacement for fine aggregate which used in construction as ordinary concrete material. In this study, foamed concrete with target density 1400, 1600 and 1800 kg/m3 has been produced. The compressive strength of foamed concrete with RHA has been tested. Concrete with Ratio 1:3 of RHA/Sand has higher compressive strength than ratios 3:1 and 2:2 of RHA/sand for every density. XRD and XRF test has been used to determinate chemical composition and crystalline structure of RHA. The result showed that RHA is an amorphous material which amorphous is important thing to pozzolanic process when hydration of cement paste. SEM and EDS test has been conducted to determine microstructure and chemical composition on microstructure of RHA foamed concrete. Amorphous RHA incorporating cement paste produces pozzolanic reaction. It is reduces the porosity and width of interfacial zone in such a way the density is increase.

Potential of RHA in Foamed Concrete Subjected to Dynamic Impact Loading

In relation to the conventional concrete then foamed concrete (FC) is weaker. Therefore FC was added by Rice Husk Ash (RHA) to alter the strength without eliminating its characteristic as aerated concrete. Actually function of RHA is substitute the sand partly. The strength of concrete affects to prevent the dynamic impact loading. However FC as aerated concrete can absorb energy impact by its porosity. Both of characteristics were presented in this investigation. SEM and EDS detected that pozzolanic reaction was done when FC was processing hydration of cement in admixture. The presence of RHA increased the strength of concrete owing to cement hydration process and pozzolanic reactivity of RHA. The result of impact loading on slab FC target displayed that FC with RHA was more shallow than without RHA. Beside of that local damage showed that FC with RHA denser and is not impression of fragments than FC without RHA.

Investigation on Energy Absorption of Slab Foamed Concrete Reinforced by Polypropylene Fibre Subjected to Impact Loading

Polypropylene Fibre (PF) as reinforcement has contributed to the intensity of Foamed Concrete (FC) slab when subjected to impact loading. The presence of PF in the admixture reduces the micro-porosity that generates the micro-crack of the slab. However, the fibrillation of PF in the admixture enhances the bonding mechanism system between PF and the FC matrix. The impact test conducted uses an instrumented drop-weight impact tower. Results show that FC without PF produces a distinct radial crack and clear fragments within the crater field unlike FC with PF. However, both slab materials did not generate spalling nor scabbing upon impact and the influence of porosity produces only local damage due to the mechanism of brittle crushing effect of porous walls. In this study, the energy absorption between FC with and without PF was investigated and from observation produces only minor differences. Results also verify that FC with PF did not loss its ability to absorb energy upon impact.

Leaching Behaviour of Organic Materials in Reinforced Concrete Artificial Reef with RAC

This paper reports the leaching behaviour of pineapple skins incorporated in the artificial reef fabricated from recycle aggregate concrete. Pineapple skin was mixed with the concrete as added material which produce nutrients to attract fish habitat. Material test was conducted on the concrete reef specimens to determine its compressive strength. The nutrients dispersed were measured by using total phosphorus and nitrate test of the water sample collected from each of the artificial reef within the six days duration. Results showed the compression strength of the reef decreased with the increase of percentage pineapple skin used. However, it was found that the total phosphorus and nitrate leached from the reef increased gradually with time as the percentage of pineapple skin used increased.

Investigation on Impact Resistance Foamed Concrete Reinforced by Polypropylene Fibre

Foamed Concrete (FC) needs high strength to prevent dynamic loading, thus it is important to enhance the ductility. Usage the Polypropylene Fibre (PF) examined its contribution in strength of FC on impact resistance. Microstructures were observed that air voids in matrix of FC produce micro-porous that reduce interfacial bonding into matrix and generate micro-crack that may propagation crack growth. Presence of PF in admixture results fibrillation and reduces micro-cracks. Tensile test was investigated that PF delays crack growth in matrix. In this investigation impact test were conducted using an instrumented drop-weight impact tower. When impactor hits the target surface in free surface condition causes compressive plastic wave transform to be tensile wave. It was affected by tensile strength therefore local effect has not found spalling in crater field. In addition influence of porous in matrix FC has ability to absorb the energy and it was not found distal crack around surface area. Penetration depth results showed FC with PF subjected to impact loading was lower than without FC. Presence of PF increases FC strength and local effect results there was not impression of fragments around distal surface due to brittle crushing.

Influence of Polypropylene Fiber in Strength of Foamed Concrete

Foamed concrete is material that can be used in wide range of constructions and produced in high density. This investigation examined effect of chopped Polypropylene Fiber (PF) that mixed into admixture concerning strength of foamed concrete high density. Mechanical test were performed to measure effect of PF on improving compressive and splitting tensile strength. Result indicate that PF significantly improving compressive strength and behavior of PF where drawn into foamed concrete similarly with normal concrete. The fibrillated PF has been occurred and reduced the micro crack of matrix and prevented propagation crack growth. The presence of PF improved splitting tensile strength was not significantly. Influence of porous of foamed concrete is considered. Scanning Electron Microscope (SEM) exhibits condition microstructure of foamed concrete reinforced PF that alter microstructure, especially interfacial bonding due to PF presence.

Contribution of Polypropylene Fibre in Improving Strength of Foamed Concrete

Foamed concrete as favorable substitution conventional concrete can be used in wide range of constructions. Usage the Polypropylene Fibre (denoted as PF) in this investigation examined contribution of PF on strength of foamed concrete. Mechanical test were performed to measure effect of PF on improving compressive and splitting tensile strength. Results indicate that PF significantly improving compressive and splitting tensile strength. Behavior of PF where drawn into foamed concrete similarly with normal concrete. The fibrillation and interfacial bonding between PF and matrix has been occurred and reduced the micro crack of matrix and prevented propagation crack growth. However influence of porous of foamed concrete is considered. Process of curing continuation 60 and 90 days indicate that interfacial adhesion is wider when cement hydration process is running. Scanning Electron Microscope (SEM) exhibits condition microstructure of foamed concrete added by PF alter the microstructure, especially interfacial bonding between PF and matrix.

Development of Green Concrete from Agricultural and Construction Waste

As the demand for affordable and quality houses increases in the 11th Malaysia Plan, issues regarding environmentally sustainable construction gain more prominence as specified by the Construction Industry Transformation Plan, CITP 2016–2020. The emphasis on green construction has been stressed by the introduction of the strategic plan, and, hence, the need for a construction system which is eco-friendly, reduces carbon emission and uses less earth natural resources is required. Thus, this paper studies the past and present research on green concrete utilizing agricultural waste and construction waste. Agricultural waste such as palm oil fuel ash (POFA) and rice husk ash (RHA) together with recycled concrete aggregate (RCA) from construction waste will be used as part replacement of cement and aggregate, respectively, whilst palm oil fibre (POF), which is another form of agricultural waste, will be added as binders for the concrete matrix. Literature has shown that by replacing ordinary Portland cement with POFA and RHA enhances the compressive strength and tensile strength of concrete by up to 20% and 10%, respectively. Similar trends were observed when POF were added to concrete where improvements in its strength and crack properties were observed. Replacing natural aggregates with RCA also has similar impact to the compressive strength of concrete, but a lower flexural strength was recorded.

An Exploratory Compressive Strength Of Concrete Containing Modified Artificial Polyethylene Aggregate (MAPEA)

Concrete is widely used in the world as building and construction material. However, the constituent materials used in concrete are high cost when associated with the global economic recession. This exploratory aspires to have an alternative source of replacing natural aggregate with plastic wastes. An investigation of the Modified Artificial Polyethylene Aggregate (MAPEA) as natural aggregate replacement in concrete through an experimental work was conducted in this study. The MAPEA was created to improve the bonding ability of Artificial Polyethylene Aggregate (APEA) with the cement paste. The concrete was mixed with 3%, 6%, 9%, and 12% of APEA and MAPEA for 14 and 28 curing days, respectively. Furthermore, the compressive strength test was conducted to find out the optimum composition of MAPEA in concrete and compared to the APEA concrete. Besides, this study observed the influence and behaviour of MAPEA in concrete. Therefore, the Scanning Electron Microscopy was applied to observe the microstructure of MAPEA and APEA concrete. The results showed the use of high composition of an artificial aggregate resulted inferior strength on the concrete and 3% MAPEA in the concrete mix was highest compressive strength than other content. The modification of APEA (MAPEA) concrete increased its strength due to its surface roughness. However, the interfacial zone cracking was still found and decreased the strength of MAPEA concrete especially when it was age 28 days.