Palm Oil Fuel Ash (POFA) is one of the solid waste in Malaysia and had trouble with the ash removal. Therefore, the use of waste oil palm ash can overcome the problem of solid waste. POFA is a pozzolanic material and it can act as a replacement of cement (OPC) to produce concrete with higher strength and low cost. POFA quality will increase as the range made up to a medium level of fineness in the size of 50 microns. POFA used to replace OPC is 0%, 10%, 30% and 50% by weight percent of OPC. POFA concrete compressive strength will be tested after a curing process that concrete age of 7 days and 28 days. POFA concrete density is also tested and compared with OPC concrete. Results showed that compressive strength POFA lower than normal concrete. On the other hand, the replacement of cement by 10% POFA shows a record high in compressive strength compared with other POFA mixing at the age of 7 days and 28 days. Fineness pozzolanic POFA is the best material and can be used as a cement replacement alternative.

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Exposure of concrete to intense heat will cause deterioration of its strength and durability. Previously, the fire-damaged concrete was repaired using the shotcrete and normal concrete. Recent studies utilize fibre reinforced polymer (FRP) in repairing fire-damaged concrete. Ultra High Performance Fiber Reinforced Concrete (UHPFRC) mostly developed using fine size aggregate, cement, silica fume, super plasticizer and reinforced with steel fibre has an excellent mechanical properties compared to high strength concrete and with an addition of steel fibre in the UHPFRC enhances its ductility behaviour which is not possessed by normal concrete, hence, UHPFRC indicates a promising candidate as repair material to fire-damaged concrete. The aim of this paper is to review on the properties of UHPFRC to be utilized as repair material to fire-damaged concrete structure based on previous research on UHPFRC and fire-damaged structure.

Waste tyre caused disposal problem in country all over the world. A lot of research has been done to make use of recycled tyre rubber to minimize waste tyre disposal problem. Recycled tyre rubber has been widely used for civil engineering application such as lightweight concrete and asphalt pavement. However only a few study focused on the development of material using recycled tyre rubber as drainage material for geotechnical purposes. This paper presents the experimental on properties of cement-based material consisting recycled tyre rubber. Specimens were prepared by incorporating different percentage of shredded rubber tyre with mortar. Summation of ten (10) mixes has been investigated to determine the compressive strength, density, porosity and water absorption. From the results, it is concluded that the higher percentage of shredded tyre rubber used, will decreased the compressive strength and increased the porosity and of the material.

Most of the rice husk is disposed with no further concern and this has caused waste disposal problems. Burning rice husk can cause health and environmental problem. Rice husk ash has been widely used for concrete technology application as additive in concrete mixture. However there is lack of study on the usage of raw rice husk. This paper presents the experimental on the properties of cement mortar consisting raw rice husk which focused on the porosity and density. Specimens were prepared by incorporating different percentage of rice husk with mortar. Summation of 10 mixes has been investigated to determine the compressive strength, density, porosity and water absorption. As the main purpose of the rice husk cement mortar is for drainage material, the main characteristics needed are porosity and lightweight. From the results, it is concluded that the higher percentage of rice husk used, will decreased the compressive strength and density and increased the porosity of rice husk cement mortar.