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Self Compacting Concrete (SCC) is able to compact under its own mass in thin sections and in congested reinforced zones due to its high fluidity and cohesiveness. In order to produce an eco-friendly self compacting concrete with characteristic compressive strength of 40MPa, a fine industrial by-product silica fume is used as a partial substitutefor cement by weight (5%, 7.5% and 10%) and in addition to that quarry dust is partially replaced for natural fine aggregate from 5 to 15% with an increment of 5%. To study the effect of silica fume and quarry dust in fresh and hardened properties of medium strength self compacting concrete, 10 different SCC mixes were designed using Japanese method. From the experimental studyit was observed that the SCC mix containing 7.5% silica fume and 5% quarry dust exhibits the equivalent properties as that of SCC mix made with conventional materials and found to be optimum. Also, analytical expressions are proposed to predict the indirect tensile strength and flexural strength of SCC in terms of compressive strength and the results are compared with the existing codal provisions.

The furniture industry is a company that utilizes forest products in the form of wood as the main raw material in the production process. The wood used by the furniture industry in Indonesia reaches 2.6 million m3 per year. The waste generated reached 54.24% of the total production. Sawmill waste generated as much as 1.4 million m3 per year. Based on field observations in several furniture industries in the Sumbawa Region, most industries produce sawdust waste that has not been used optimally, so that sawdust waste accumulates in the soil and decomposes which can trigger environmental pollution and water pollution. Teak sawdust waste has a high cellulose content so it plays an important role as a reinforcement raw material in the manufacture of particle composites. In this study using the hand lay up method of making composite particles by utilizing waste teak sawdust as raw material for reinforcement and epoxy matrix with volume variations of 30:70%, 40:60%, 50:50%, 60:40%, 70:30. %, to obtain quality composite characteristics. Water absorption obtained 14%, each composite specimen has met the standard of SNI 03-2105-2006. The results of physical tests on the water absorption of particleboard composites were the lowest at 0.48% at 30% powder volume with 24 hours immersion due to the wood powder being mixed and bonded evenly by the matrix so as to reduce voids, while the highest yield was 9.41% in 70% volume is due to the matrix not being able to bind evenly, causing voids to occur. It can be concluded that the increasing volume of powder and the length of time of immersion, the greater the percentage value of water absorption produced.

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