Investigating the properties of cement grouted bituminous mix with alternative grout compositions

Abstract

Pavements mainly found in urban areas do not last as long as desired and are subject to premature distress. An emerging solution is cementitious material grouted bituminous mix having characteristics in between rigidity and flexibility. This study aims to investigate the properties of cement grouted bituminous mixes with alternative grout compositions. Two alternative grouts are considered where one is composed of ordinary Portland cement, fine sand, silica fume, and water, while the other is composed of ordinary Portland cement, fine sand, fly ash, silica fume, and water. The air void content was kept in the range of 20 to 30% based on compaction effort. Using the Marshall Stability test, the optimum bitumen content of the open graded bituminous mix was determined. Grouting is done manually in a skeleton, allowing the grout to penetrate underneath. It is then cured for three days, seven days, and twenty-eight days at room temperature. To study the detailed behaviour of open-graded cement grouted bituminous mix, Marshall Stability tests, compressive strength tests, indirect tensile strength tests, moisture susceptibility tests, and wheel tracking tests were performed. Results showed that the grouted bituminous mix provided better Marshall Stability, compressive strength, crack resistance, rut resistance, and moisture susceptibility than the conventional mix. It was observed that grouted bituminous mix showed marginal differences in its properties among both grout compositions.