Experimental Study of Engineering Specifications of Concrete Containing Local Mineral Pozzolan based on XRD and SEM Analyses

Global warming and its effects on the environment can be considered as the important crises facing humans. Finding a method to reduce cement consumption can be an effective step in controlling the annual increase in global temperature. In this research, in order to find the optimal mixing design for replacing local mineral pozzolan instead of a part of cement, two mixing projects with four types of 5, 10, 15 and 20 percent by weight replaced a part of concrete cement.The compressive strength and concrete quality tests were evaluated in the specimens. The constituent elements of concrete and the effect of adding local mineral pozzolan were investigated using the XRD analysis, as well as the morphology and microstructural behavior of concrete with the SEM test. The results exhibited that the best replacement value of cement by pozzolan in concrete is equivalent to 15 percent by weight of cement. Pozzolanic samples increase the strength by 24% compared to plain cement concrete (PCC) samples. Optimal pozzolanic reaction reduced the amount of portlandite and calcite in concrete. Also, this pozzolan reduced the pores, increased the improvement and integrity of the interfacial transition zone (ITZ) in concrete in comparison with plain cement concrete. Considering the effects of this pozzolan on strengthening the structure and reducing the consumption of cement in concrete, the studied local mineral pozzolan can be introduced as a green material that reduces cement by increasing the strength of concrete and is environmentally friendly.