Mechanical Properties of Concrete Incorporating Bentonite and Zeolite as Replacement of Cement

The production of concrete consumes huge amounts of natural resources. Due to the consumption of natural resources for cement production, using industrial waste materials has gained interest among researchers. Environmental issues are one of the most important issues that should be taken into consideration. Zeolite and bentonite are considered as natural pozzolans, they are easy to extract and count as environmentally-friendly raw material compared to ordinary Portland cement (OPC). In the current study, these materials were utilized blended with other materials and individually. Compressive strength, water absorption, tensile strength, and elastic modulus of concrete samples were evaluated. Moreover, 10 different mixing designs were designed to produce samples in the same curing condition with different content of bentonite and zeolite. These samples were cured for 7, 28, and 90 days. To investigate the properties of these materials as an alternative to OPC in the concrete, the results are compared with the blank sample. The optimum mixture was obtained by 6 wt. % of zeolite and 6 wt. % of bentonite, which was gained 93% of the compressive strength of the blank sample, i.e., 12.25 MPa, after 28 days of curing. This study also showed that the water absorption of samples with zeolite and bentonite had increased in comparison with the blank sample and the optimum amount in tension was observed 10 wt. % of bentonite.