دانلود رایگان مقاله انگلیسی استفاده از زباله های شیشه در ملات سیمان فعال قلیایی - الزویر 2018

abstract

This paper presents a study on alkali activated cement (AAC) mortar produced with waste sodalime-silica glass. The waste glass was used simultaneously as a precursor and fine aggregates in the alkali activated fly ash-slag mortar. The influences of waste glass in cullet and powder forms on workability, compressive and flexural strengths, fire resistance of the AAC mortar were investigated. The experimental results showed that the workability was gradually increased as the replacement level of natural sand by glass cullet was increased, and it was significantly improved with decreasing aggregates-to-binder ratios. The mechanical properties data indicated that the compressive strength was reduced as the glass cullet content increased. However, for the flexural strength, the optimum percentage of glass cullet replacement was 50%. Due to the low reactivity, a reduction in strength was observed when the glass powder was used to replace the fly ash and slag. Nevertheless, in terms of fire resistance, the incorporation of glass cullet could improve the resistance of the AAC to high temperature exposures (800
C). In particular, the AAC mortar prepared with the glass powder as a precursor exhibited remarkable resistance to high temperature. The use of waste glass in AAC material was feasible from the mechanical properties and fire resistance points of view.

4. Conclusions

This study developed a good mechanical strength and fire resistance non-OPC cement mortar, which can be used for the fabrication of new precast construction products. The following conclusions can be drawn from this study:

The increasing replacement of NFA by WGC gradually improved the workability of AAC mortar. The reason mainly due to the smooth surface, non-absorption and larger particle sizes of glass. The reduction in a/b ratio led to a large enhancement in flow values. However, the replacement of FA by WGP caused a decrease in the workability related to the coarser particle size and irregular shape of WGP. But, there was only a slight effect on the flow value with the replacement of GGBS by WGP due to their similar shapes.

The compressive strength of AAC mortar slowly decreased as the WGC content increased. Nevertheless, the flexural strength was increased with an increase of WGC content up to 50%, and then decreased as the WGC content was further increased.

The a/b ratio had little influence on the compressive strength of AAC mortar. The explanation lied probably in the higher shrinkage due to the higher binder content (i.e. lower a/b ratio).