PENGARUH JUMLAH PENGGILINGAN TANAH LIAT SEBAGAI BAHAN PEMBUAT GENTENG TERHADAP KARAKTERISTIK GENTENG KERAMIK DARMASABA

Abstract

The results of previous research on standard Pejaten ceramic tile and
Pejaten ceramic tile with natural pozzolan pumice, complied with the Ceramic Tile
Regulation of Indonesia NI-19, showed that none of those ceramic tiles resisted the
water infiltration. The tiles constituent only received once grinding during the fabrication process. It was shown from ceramic tile industry in Darmasaba that
there were physically differences between ceramic tiles with once and twice
grinding. The ceramic tiles with twice grinding process had clear noise, smooth
texture and fine crack at the surface. In order to improve the strength of the ceramic
tiles, it was decided to conduct a research on ceramic tile characteristic with twice
grinding process.
The characteristic of the ceramic tiles to be determined were dry shrinkage, burnt
shrinkage, bending strength, water infiltration and water absorption. The ceramic
tile specimens were mixed with a ratio of 1:0.15 of clay : paras pollen batched by
volume with a sufficient water amount. The research variable was a number of
grinding.
The result showed that the ceramic tiles with once grinding had an average water
absorption of 24,80%, the average water infiltration in 3 hours was 8,6 mm and the
ceramic tile was un-resistance to the water infiltration. The average bending
strength of whole tile was 86 kg and the flat surface of the tile was 26 kg. The
average of dry and burnt shrinkage was 7,2% and 2,2% in long direction and 6,7%
and 2,1% in short direction. The bending curvature equal to 6,35 cm. The tiles with
twice grinding had an average water absorption of 22,25%, the average water
infiltration in 3 hours was 8,1mm and the ceramic tiles was categorized resistance
to the water infiltration. The average bending strength of whole tiles was 89 kg and
the flat surface of the tiles was 28 kg. The average of dry and burnt shrinkage was
6,9% and 1,9% in long direction and 6,3% and 1,8% in short direction. The
bending curvature equal to 6,11 cm. The ceramic tiles were classified as the quality
IV.