Over the past five years extensive research has been undertaken on recycling fly ash as a particulate reinforcement in engineering polymer such as isotactic polypropylene. In this study, as received and near white color modified fly ash particles have been used. Results indicate that the tensile modulus and notched charpy impact properties are substantially enhanced by the fly ash addition. Colour modified fly ash within 5% whiteness of calcium carbonate produces composites visibly almost as white as the neat PP polymer. Addition of fly ash in PP induces between 4% to 15% of β crystals in the polymer structure, to the otherwise mono-modal α crystals.

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Concrete is one of the most widely used construction materials for infrastructure, but concrete has the disadvantage of being easy to crack. One of the factors that influence concrete cracks is rain water, because water can enter and seep into the pores. Several studies have been carried out to overcome the cracking of concrete structures; one of them is the addition of bacteria that have calcium carbonate precipitating activity. Calcium carbonate from bacterial metabolism can closed on cracked concrete surfaces. This method is commonly called Microbial Induced Calcite Precipitation (MICP). The source of bacteria in this study is bacteria at Wawalosea hot springs from the limestone mountain. The research is healing of cracks in concrete compare by bacteria MICP and MICP immobilization using alginate-chitin. The results showed that the concrete made with the addition of MICP isolates as much as 1.6x108 cells / mL had a greater compressive strength than the concrete without the addition of isolates. The value of compressive strength and absorbency of concrete water with the addition of MICP isolates has a compressive strength of 25.78 Mpa and addition imobilization MICP has 18 Mpa. So when compared to concrete without the addition of isolates and concrete with the addition of MICP isolates, the value of concrete compressive strength occurred at 100%.