SIDOARJO MUD AS A CEMENTITIOUS MATERIAL: A MYTH OR REALITY

Since the production of Ordinary Portland Cement (OPC), an essential constituent of
concrete, leads to the release of significant amount of C02
, it has created some
greenhouse effects. Many researches have been carried out to replace partially this OPC
such as using Rice Husk Ash (RHA), Silica Fume, Lime Pozzolan, Fly Ash and many
more. All this research shows and gives good result on concrete properties. Volcanic ash
is believed to have some cementitious properties that can replace OPC. Volcanic
emption and earthquake is known as a major problem in Indonesia and in Jawa Timur
(East Jawa) there is new type of catastrophe has been discovered known as Sidoarjo Hot
Mud. This abundant nature waste is used as a research item to find its effect as
cementitious material. The main objective of the study is to find the oxide and
amorphous content in this mud (cementitious component) and use this mud to improve
the quality of the concrete. The scope of study comprises of research on this mud as
cement replacement material using XRD and XRF equipment. Several tests were carried
out to find the compression and tensile strength. Porosity and Ultrasonic Pulse Velocity
(UPV) tests were also employed to determine the effect of this mud. The tests were
carried out with mixture ratio of 0, 5, I 0, 15 and 20% of Sidoarjo mud and OPC to find
the optimum ratio. The result showed that the mud can be used as cementitious material
with optimum ratio of 10% Sidoarjo mud. It was found that Sidoarjo mud mortar
achieved 30% of higher strength compared to OPC mortar. It was also noticed that the
porosity level decrease 7% compare to control specimen. In term of tensile, and UPV
tests Sidoarjo mud mortar showed 9% and 3% increases compare to OPC mortar
respectively.