Evaluation of cement grouted bituminous macadam technology: a laboratory study.

Cement Grouted Bituminous Macadam (CGBM) is a composite pavement that can offer sustainability in the pavement construction sector. The main objective of this study emphasises designing and evaluating the CGBM mixes prepared with different cementitious grouts and aggregate gradations. Compressive strength (7 and 28 days), Flexural strength (28 days), Marsh cone flow, and Initial and final setting time were considered for optimising the cementitious grouts. The details of several investigations on CGBM that include Marshall stability, Compressive strength, Indirect Tensile Strength (ITS), Resilient Modulus (Mr), Fracture energy, and Cantabro abrasion test were reported. The experimental results showed that sand and micro silica influence the mobility of grout to a greater extent. Percolation of grouts into Open Graded Friction Course (OGFC) mixes was a critical concern for grouts with flow time longer than 35 s. A reduction in the pore volume and reduced interconnected links in finer gradation resulted in improper full-depth penetration (FDP) characteristics. Mixture level tests for CGBM revealed that Mr of CGBM improved by about 6 times compared to the bituminous mix. In addition, CGBM showed high tensile strength with rapid crack propagation behaviour. Further, pavement design demonstrated a 35% of thickness reduction and cost reduction due to CGBM implementation. [ABSTRACT FROM AUTHOR]