RH-based sensitivity modeling and performance classification framework for internally cured waste glass beads mortars

Abstract

This study proposes a multi-index evaluation framework to assess the internal curing effectiveness of lightweight aggregate mortars under variable relative humidity conditions. Traditional strength-based evaluations often overlook RH-induced variability, prompting the introduction of four RH-normalized indices: Strain Interval Sensitivity, Mass Change Interval Sensitivity, Strength Efficiency Index, and RH Resilience Index. These indices collectively capture shrinkage sensitivity, mass loss, strength efficiency, and robustness to RH fluctuations. Mortars incorporating waste glass beads were experimentally investigated and classified into four performance categories (Class I–IV) using a quadrant-based SIS–MCIS map, where SEI is represented color and marker size. Notably, W20 exhibited high absolute strength but low RH stability, while W100 demonstrated high RH resilience despite moderate strength. Unlike regression-dependent models, this classification approach provides an intuitive, reproducible method for field-oriented material assessment. It enables scalable mix design, performance monitoring, and quality control tailored to RH-sensitive construction environments.