Assessment of cement hydration and strength development in agro-waste concrete using destructive and non-destructive techniques

The Electro-Mechanical Impedance (EMI) technique is employed with the help of piezo sensors in this study, which explores hydration behaviour of sustainable concrete partially substituting Ordinary Portland Cement (OPC) with agro-waste materials such as Rice Husk Ash (RHA) and Sugarcane Bagasse Ash (SCBA). To determine the maximum percent of replacement which satisfies the balance between strength and durability, concrete mixes of M30 grade were prepared using various replacement levels (SCBA: 0–25%, RHA: 0–15%). In-situ conductance signatures, root mean square deviation (RMSD) and correlation coefficient (CC) were acquired from 1 h to 28 days using the destructive compressive strength test as well as embedded piezoelectric sensors. The findings revealed that 20% SCBA and 10% RHA were optimal replacement levels in terms of high strength, microstructural refinement, and long-term stiffness enhancement. RHA showed consistent hydration and high reactivity, according to early-age EMI analysis, while SCBA showed delayed but notable pozzolanic activity, enhancing late-age strength. OPC exhibited relatively less refinement but faster initial hydration. The study supports the use of agro-waste materials for environmentally friendly construction by confirming EMI as a sensitive, non-destructive monitoring tool for hydration kinetics and structural evolution in sustainable concrete.