Comprehensive Study of Partial Replacement of Cement with Biochar in Concrete

Concrete is the most extensively used construction material in the world. Among the constituents of concrete (cement, coarse aggregate, fine aggregate) cement is the most expensive one. The production process of cement leads to generation of CO2. It is estimated that nearly 8% of global CO2 is generated during the production of cement. The objective of this study is to find the suitable replaceable material instead of cement. In this study biochar is used as a material for partially replace the cement. Biochar is a type of charcoal produced from biomass through a process called pyrolysis which involves burning of organic material in absence or limited supply of oxygen. Cement is replaced with biochar at 1%, 3%, 5%, 7%, 9%, 11%, and 13% by the weight of the cement. Slump tests as well as compressive strength test are performed on fresh and hardened concrete after curing period of 7 and 28 days. The results are then compared with conventional concrete (at 0% replacement) to determine the best combination of replacement of the material. From the investigation it was observed that 5% of biochar is best suitable for replacement of cement in concrete mix.