Thermomechanical Behavior of Different Types of Concrete with Vermiculite

At elevated temperatures, the mechanical behavior of concrete can become unfavorable, compromising the integrity of structures. In light of this, it becomes imperative to investigate and develop concrete formulations that can deliver superior performance under high-temperature exposure conditions. In this context, the present study explores the substitution of 25% of sand with expanded vermiculite in both conventional and high-performance concrete, with project strengths evaluated at 35, 50, and 70 MPa. To achieve this, the physical and mechanical properties of the concretes were assessed at room temperature and at 200°C, 400°C, and 800°C. Among the results obtained, it is noteworthy that vermiculite reduces the workability of the concrete mix. From an exposure temperature of 400°C onward, all concretes exhibited cracking. In general, concretes with a project strength of 50 MPa benefit from the substitution of fine aggregate with vermiculite.