Utilization of date pits waste as aggregate alternative in sand-epoxy-resin composite. (10th March 2020)

• Record Type: Journal Article
• Authors: Dalhat, M.A.
• Is Part Of: Construction & building materials. Volume 236(2020)
• Publication Date: 2020-03-10
• Subjects: Epoxy resin mortar -- Date pits -- Polymer concretes -- Moisture resistance -- Recycling -- Date pit composite; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2019.117585
• Languages: English
• ISSNs: 0950-0618

Abstract

Graphical abstract: Highlights: Date pits (DP) aggregate with enhanced moisture resistance were formulated. DP-sand-resin compositions containing various levels and types of DP were evaluated. Resin and paint treatments resulted in more than 80% improvement in size stability of DP. Up to 20% DP in the resin mortar will not cause significant loss in compressive strength. Up to 35% improvement in flexural strength can be achieved for 20% DP content. Flexural strength gain was due to surface bonding of DP with the sand-resin matrix. Abstract: The mechanical properties and fracture behavior of low epoxy-resin mortar compositions containing Date pits (DP) as aggregates substitutes were studied. This study aimed to exploit the DP physical appearance and mechanical characteristics' to formulate DP-sand-resin compositions with improved mechanical properties and unique finish. Four types of DP with enhanced moisture resistance were prepared and examined. DP-sand-resin compositions with 0%, 10%, 20%, 30%, and 40% DP aggregate replacement for three main types of DP were analyzed. Painting along with resin coating treatments have resulted in 75%, 95%, 99%, and 80% decrease in the DP moisture absorption, midsection expansion, top/bottom expansion, and longitudinal elongation respectively. It was found that adding more than 20% of the various types of DP to the sand-resin composition will result in significant decline in compressive strength. But adding the DP to the sand-resin composition resulted in an increase, then later a decrease in its flexural strength, for all types of DP. Maximum increase in flexural strengths of approximately 35%, 28%, and 21% for sand-resin compositions with 20% untreated DP, 20% paint coated DP, and 10% resin coated DP, were observed respectively. The improvement in the flexural properties were found to be due to the additional mechanical bending support offered by the DP through surface bonding with the sand-resin matrix. Finally, 20% of DP content for the different types of DP was found to be the limit for net mechanical performance improvement. But at or below 30% DP contents, the composites met the minimum compressive strength requirements for load-bearing concrete masonry unit, and for non-load bearing concrete masonry unit above 30% DP content.