INVESTIGATION OF MECHANICAL AND MICROSCOPIC PROPERTIES OF RECYCLED CONCRETE BASED ON GEOPOLYMER POWDER CONTAINING LIME AND METAKAOLIN

Mechanical and micro analyzes were

carried out on the recycled concrete samples obtained by preparing different mixtures

of geopolymer powder, metakaolin, lime, quartz and sodium silicate as alkali

activator and sodium hydroxide solution, which were formed by grinding the

geopolymer concrete samples prepared with certain temperature and low curing

times. Recycled concrete samples with geopolymer powder, with a weight ratio of

36% in 1m3 volume, were prepared at 60<!--[if gte msEquation 12]><m:oMath><m:r><m:rPr><m:scr m:val="roman"/><m:sty m:val="p"/></m:rPr>℃</m:r></m:oMath><![endif]--><!--[if !msEquation]--><!--[if gte vml 1]><v:shapetype

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showed that the highest compressive strength of the mixtures was 77.89 MPa with

the increase of the lime ratio in the 8 hour curing period. It was determined

that the highest compressive strength was 73 MPa in the samples in which

metakaolin was never used and the lime ratio was maximum, the compressive

strengths of the samples with 0.05% lime ratio of metakaolin and 0.025% lime

ratio of metakaolin and 0.05% lime ratio of metakaolin were 74 and 77.89 MPa,

respectively. In addition, capillary permeability tests were also carried out

on the samples. Capillarity coefficients of geopolymer mixtures are below 0.377

kg/m2.min0.5. It has been suggested that concrete mixtures produced from

recycled geopolymer powder can be used in the load-bearing elements of

structures that need to remain at the level of use immediately under the effect

of dynamic load.<o:p></o:p>