CHEMICAL CHARACTERISTICS OF VOLCANIC ASH IN INDONESIA FOR SOIL STABILIZATION: MORPHOLOGY AND MINERAL CONTENT

Abstract

Indonesia region which has approximately 83 active volcanoes are a source of wealth of this region. The last five years, active volcanoes in Indonesia, Mount Merapi, Kelud and Sinabung eruption issuing experiencing the abundant material. A volcanic ash from the eruption of volcanic material can be used as soil stabilization. Volcanic ash is a pozzolanic material which can be used as a soil stabilizing agent. However, it should be done the first step characterization testing of chemical properties, mineralogy and morphology volcanic ash from different sources. Accordingly, this paper presents results of a test chemical characteristics, mineralogy and morphology of volcanic ash in Indonesia derived from the Mount Merapi, mount Sinabung and mount Kelud using Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD). Based on specific gravity test results on some volcanic ash in Indonesia, it can be classified in light material category. Merapi, kelud and Sinabung volcanic ash has a different shape morphology. Merapi is a form of fibrous glass particles Contain elongated vesicles. While, the texture Sinabung is a berry-like glass particles show angular blocky forms and texture kelud are sponge like glass. The SEM-EDS test obtained Si content of the three types of volcanic ash ranges 45-60% and elements of Al ranges 14-20%. This can be a reference for further research on the utilization of materials of volcanic ash as a pozzolanic material in soil stabilization.