Assessment on the Potential of Volcano Ash as Artificial Lightweight Aggregates using Geopolymerisation Method

Following the Yogyakarta earthquake on May 27th, 2006, the subsequent eruption of a volcano mud hasbeen closely observed and analyzed by the geological community. The volcano mud, known as LUSI (LU-lumpur, SI-Sidoarjo), began erupting near the Banjarpanji-1 exploration well in Sidoarjo, East Java, Indonesia.LUSI offers a unique opportunity to study the genesis and development of a volcano mud. This papersummarizes the current knowledge about the potential of volcano ash as a raw material in geopolymer andas artificial aggregate. Previous experimental study shows that the volcano ash has a good performancewhen 5% and 10% OPC was replaced by volcano ash mixture. Volcano ash mixed with fly ash in certaincomposition has a potential to become a binder in geopolymer concrete. An effort to convert the volcano ashto artificial aggregate also shows good potential due to their specific gravity and water absorptions, andcharacterization of this material. The characterization of this material have been done through X-rayFluorescence (XRF), X-ray Diffraction (XRD), Scanning Electron Micrograph (SEM), and Fourier TransformInfrared Spectroscopy (FTIR), and then compared to other materials. Sintered volcano ash showed goodperformance in terms of strength as a cement replacement material with OPC and fly ash. Volcano ash alsoshowed good performance for porosity. This material has a potential as a raw material due to high compoundsof SiO