Properties of Alkali Activated Lightweight Aggregate Generated from Sidoarjo Volcanic Mud (Lusi), Fly Ash, and Municipal Solid Waste Incineration Bottom Ash.

Puput Risdanareni,Katrin Schollbach,Nele De Belie,Yury Villagran,Jianyun Wang

doi:10.3390/ma13112528

Abstract

Production of artificial lightweight aggregate (LWA) from industrial by-products or abundant volcanic mud is a promising solution to prevent damaging the environment due to the mining of natural aggregate. However, improvements are still needed in order to control the high water absorption of LWA and strength reduction in resulting concrete or mortar. Hence in this research, fly ash, municipal solid waste incineration bottom ash (MSWI BA), and Sidoarjo volcanic mud (Lusi) were employed as a precursor and activated using NaOH 6 M and Na2SiO3 in producing LWA. The influence of the type of the precursors on the physical properties of resulting LWA was investigated. The effect of replacing natural fine aggregate with the resulting LWA on the compressive strength and volume density of mortar was also determined. Finer particles, a high amount of amorphous phase, and low loss on ignition (LOI) of the raw material improved the properties of resulting LWA. Mortar compressive strength was decreased by 6% when replacing 16% by volume of natural fine aggregate with fly ash based LWA. Compared to the expanded clay LWA, the properties of alternative LWAs in this study were slightly, but not significantly, inferior. Alternative LWA becomes attractive when considering that expanded clay LWA requires more energy during the sintering process.

Highlights

The global demand for aggregates is increasing along with increasing concrete demand
A comparison with the results reported by Gesoglu et al, who substituted 25 % of fine aggregate with a cement-bound fly ash lightweight aggregate (LWA) in mortar, shows that the decrease in strength in comparison with the reference mortar obtained in the present research was much lower [10]
The type of raw material had no significant effect on the particle size distribution of the resulting

Summary

Introduction

The global demand for aggregates is increasing along with increasing concrete demand. With the increasing demand for aggregates, especially in the concrete industry, the availability of natural aggregate will decrease as this material is non-renewable and continued mining will lead. Developing a new artificial aggregate from industrial waste and abundant volcanic material could be a promising solution. As much as 50 million m3 of this mud has been placed in a giant embankment with an area of 640 ha. This eruption caused a massive loss of habitable land at Sidoarjo and was recognized as a national disaster in Indonesia [2]

Objectives

Methods

Conclusion