Effect of Gravel-sand Ratio on Physico-mechanical, Thermal and Macrostructural Properties of Micro Epoxy Polymer Concrete based on a Mixture of Alluvial-dune Sand

Zineb Kerrida,Zoubir Makhloufi,Hichem Berkak,Ahmida Ferhat,Madani Bederina

doi:10.2174/1874149502014010247

Abstract

Introduction: In the Polymer Concrete (PC) composites, aggregates are the most important constituent, which considerably affect their performance. The purpose of this experimental study is to examine the effect of Gravel-to-Sand (G/S) ratio on the physico-mechanical, thermal and microstructural properties of epoxy micro-polymer concrete made up of local aggregates. Materials & Methods: The Micro Epoxy Polymer Concrete (MEPC) studied consists of epoxy resin as a binder and a mixture of two types of sands (alluvial (0/0.63 mm) and dune (0/4 mm) sands), as well as crushed limestone gravel (3/8 mm). Six compositions were prepared with two epoxy resin contents (10% and 14% of the total weight of mixture) and three G/S ratios (0.25, 0.50 and 0.75). The studied properties are density, water absorption, compressive and flexural strengths, thermal conductivity, thermal diffusivity, specific heat and macrostructure. Results & Discussion: The obtained results show that the G/S ratio, as well as the epoxy resin content, has a significant influence on the properties of MEPC. In addition, 14% epoxy resin and the G/S ratio of 0.75 can be considered as optimal values, which lead to very interesting physico-mechanical performances (denser and less porous material, more resistant with almost similar thermal conductivity). Moreover, the density, the water absorption and the optical microscopic observation confirm that mixes containing 14% epoxy are more impermeable, compact and homogeneous than those containing 10% epoxy. Conclusion: Finally, it should be noted that the incorporation of aggregates being relatively coarse decreases the grains’ specific surface and reduces the porosity of the granular mix, which enable the epoxy product to completely cover the surface of mineral grains. A perfect covering of aggregate grains with a bender improves the adhesion between the aggregates and the polymer matrix.

Highlights

In the Polymer Concrete (PC) composites, aggregates are the most important constituent, which considerably affect their performance
This is likely due to the use of coarse aggregates, which reduce the large pores by producing a high-density Micro Epoxy Polymer Concrete (MEPC) [37]
The results of the compression strength test of MEPCs are presented in Fig. (10). These results show a trend almost similar to that observed in the evolution of the flexural strength of MEPCs

Summary

Introduction

In the Polymer Concrete (PC) composites, aggregates are the most important constituent, which considerably affect their performance. The purpose of this experimental study is to examine the effect of Gravel-to-Sand (G/S) ratio on the physico-mechanical, thermal and microstructural properties of epoxy micro-polymer concrete made up of local aggregates. Aggregates and fillers typically occupy more than 40-80% of the volume of PC [10, 13], and they play a key role in the mechanical and other properties [14]. The polymer used is an epoxy resin whose trade name is “MEDAPOXY STR” from the Algerian Granitex company This epoxy mixture is obtained by an epoxy resin prepolymer (part A) / hardener (part B) weight ratio of 3/2, according to the manufacturer’s recommendations.

Objectives

Methods

Results

Conclusion