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The use of concrete for construction had become very common in developing countries. But concrete is not friendly environment because of it consumes huge quantities of natural materials and production of the cement, which is a major contributor to greenhouse gas emissions and global warming. The aim of this study is to investigate the Sustainable Green Concrete (SGC) which containing biomass aggregate; fly ash and Superplasticizer. Biomass aggregate and fly ash are waste industry products which are environmentally friendly. The study was carried out to identify the chemical properties of biomass aggregate, and to determine the chemical properties and optimum mix design of the Sustainable Green Concrete (SGC). A total of 90 cube samples were casted and compressive strength were tested at the age of 7, 14 and 28 days. The overall results showed that the workability and compressive strength were decreased with the increase of the replacement of natural aggregate with biomass aggregate. Besides that, the workability and compressive strength was increased with the incorporation with the replacement cement by fly ash. The SGC gained highest compressive strength for the concrete mixes of 39.3 N/mm2 with the optimum percentage used of SGC in producing concrete not exceeding 30% biomass aggregate and 6% of fly ash as a partial replacement with natural aggregate and cement respectively. The results obtained and observation made in this study suggested that biomass aggregate and fly ash are successfully used as partial replacement in producing SGC and can perform better strength development.

This Forensic project has been proposed to investigate the reinforced concrete structure defect at library. There were found 65 points cracks and 20 points spalling in library such as only at reinforced concrete beam and slab part in first floor. The total of cracks which crack width less than 0.25 mm is 63 points and the crack width between 0.25 mm to 5.00 mm is 2 points only. These cracks had categorized as fine cracks because the crack width not more than 5 mm. There was 21 samples Rebound Hammer test was random measured the existing concrete compressive strength of critical structures which six samples at beams, six samples at slabs, six samples at columns and three samples at staircase in library. The Rebound Hammer test shown that average mid-point strength at beam is 33 N/mm 2 , slab is 25 N/mm², column is 38 N/mm 2 and staircase is 37 N/mm 2. Based on the Eurocode 2, the minimum grade concrete required is 25N/mm 2 to do the design for reinforced concrete structures, which all the existing concrete strength were achieved the minimum concrete strength. Finally, the Orion software are used to analysis and determine the size of steel reinforcement, the design found the required bar size of steel reinforcement at the middle span or continuous support is 2T16 & 2T25 or 2T20 & 2T25 but the existing steel reinforcement is 2T12 and 2T20 which the existing steel reinforcement could not be sustained the big loading that applied on the library.

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Magnesium Oxide (MgO) board has been widely used in prefabricated lightweight steelframe wall systems and as the floor board covering component. It is a non-insulating sheathingboard product which consists of sustainable materials with the characteristics of fire resistance,weather-ability, strength, resistance to mold and mildew. Although MgO board has recentlyworldwide used in façade construction but the research data related to the laboratory work such asthe bending strength is still limited. The previous studies on the bending strength of MgO board arebased on various standards such as ASTM, JC688 and British Standard subjected to the productscharacteristics and patterns. Therefore, the bending strength values obtained were inconsistent andnot convincing. Thus, this paper aims to examine the bending strength of MgO board with threedifference thicknesses (6mm, 9 mm and 12 mm) based on BS EN 310:1993 subjected to threepoints bending test. The failure modes during three points bending test was observed and theexperimental results obtained were compared with the theoretical values and others relevantstandards. A total of thirty six specimens with twelve specimens for each thickness in two groupdirections namely longitudinal (length) and transverse (width) direction were tested. The specimenswere prepared based on BS EN 326-1:1994 and BS EN 325:2012. The maximum flexure load of thespecimens was recorded and arithmetic mean bending strength for each thickness was presented.The experimental results showed the tested MgO board was not achieved minimum bendingstrength for load bearing used. It is recommended to be used in non-load bearing façade claddingconstruction.