Study on Brick Dust for GSB Layer of Flexible Pavement

This study investigates the potential of locally available Brick Dust as a partial replacement for sand in Granular Sub-Base (GSB) layers for road construction, following MORTH specifications. Brick Dust was incorporated at four replacement levels—10%, 20%, 30%, and 40%—and evaluated through gradation analysis, compaction testing, and California Bearing Ratio (CBR) assessment. While all mixes satisfied the gradation and non-plasticity requirements, significant variation in strength characteristics was observed. The mixes containing 10%, 20%, and 30% Brick Dust failed to achieve the minimum CBR value required for GSB applications, indicating inadequate load-bearing capacity. Conversely, the 40% Brick Dust mix exhibited optimal performance, achieving CBR values well within the acceptable range and demonstrating improved compaction behavior. The findings confirm that 40% Brick Dust can effectively replace sand in GSB layers, offering a cost- efficient and environmentally sustainable alternative by reducing dependence on natural sand resources. This study supports the use of Brick Dust as a viable material for sustainable road construction practices.