The study of the usage of coral and limestone aggregates as asphaltic layer on coastal structures

Abstract

Indonesia is a maritime country with the second longest coastline in the world. Any structures constructed along the coastline, such as pavement layer on sea dike, must be able to resist the hydrodynamic forces from the waves, such as the overtopping wave. It is necessary to find an aggregate to be used as surfacing layer for sea dike and/or flexible pavement that can withstand these (compressive) forces. This research analyses the feasibility of two natural aggregates, namely the coral and limestone aggregates, to be used as an ingredient for asphalt surface layer on coastal structures. Asphalt mix samples were prepared by using these two aggregates with various percentage of asphalt. The Marshall stability, flow, and the compressive force (Flab) of the prepared samples were tested in the laboratory. The stability and the flow of asphalt samples were tested to verify that the asphalt mix satisfies the requirements specified by Standar Nasional Indonesia 06-2489-1991. Moreover, this research also calculates the overtopping waves by varying the height and the period of the waves. The results were then converted as a compressive force (Fwave) and compared to the Flab to see whether the prepared samples could resist the calculated Fwave.