WEATHERED MARBLE AS AN ALTERNATIVE EMBANKMENT MATERIAL FOR ROADWAY DEVELOPMENT IN NORZAGARAY, BULACAN

Abstract

Road networks facilitate socioeconomic growth in developing countries, such as the Philippines. An increased traffic volume exacerbates the gradual progression of erosion, breaching, and degradation of road embankments. Weathered marble from local quarries in Norzagaray, Bulacan, was repurposed to provide an economic solution. This study quantified the effect of five varying proportions of weathered marble and aggregate on index properties, such as specific gravity, grain size distribution, plasticity, and compaction, and assessed the capacity of the embankment against vehicular loads using the California bearing ratio and direct shear tests. A mix of 60% marble and 40% aggregate (60M40A) was determined to display the best performance in terms of maximum dry density (20.512 kN/m³) and California bearing ratio (78%). The Proctor compaction test results indicated a very stable embankment according to the USCS criteria and good to excellent embankment performance according to the AASHTO criteria. The local criteria on embankment marked the 60M40A samples as an excellent material for the embankment base layer. The same specimen demonstrated the highest shear strength before failure and had the highest friction angle before failure (37 degrees). These results indicate that weathered marble exhibits excellent compaction behavior, yields friction angles comparable to well-graded soil, and possesses a suitable load-bearing capacity, thus establishing its feasibility as a potential material for road embankments, especially in rural areas within proximity to marble quarrying sites.