Physical Properties and Compressive Strength of the Technical Plaster and Local Juss

الصفات الفيزيائية والمقاومة الانضغاطية للبلاستر الفني والجص المحلي

Five physical properties (water/powder ratio, setting time, fineness, porosity and dendsity) and compressive strength were determined and compared for technical plaster and local juss.Data were monitored using a standard dental stone. The relationships between these properties were also studied. It was revealed that local juss has inferior properties compared with technical plaster. It has lower compressive strength; higher water/powder ratio; shorter setting time; larger grain size and higher porosity. There is an inverse relationship between compressive strength and the two properties water/powder ratio and porosity. There is a direct relationship between compressive strength and the two properties particle size and density. There is also a direct relationship between setting time and the two properties particle size and water/powder ratio.