Mechanical and durability performance evaluation of crumb rubber-modified epoxy polymer concrete overlays

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.

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Micromechanical Modeling of Flexural Strength for Epoxy Polymer Concrete

International Journal of Applied Mechanics ◽

10.1142/s1758825117501174 ◽

2017 ◽

Vol 09 (08) ◽

pp. 1750117 ◽

Cited By ~ 3

Author(s):

Dongpeng Ma ◽

Yiping Liu ◽

Nanli Zhang ◽

Zhenyu Jiang ◽

Liqun Tang ◽

...

Keyword(s):

Flexural Strength ◽

Epoxy Resin ◽

Epoxy Polymer ◽

Resin Content ◽

Micromechanical Modeling ◽

Polymer Concrete ◽

Flexural Performance ◽

Micromechanics Models ◽

Strong Adhesion ◽

Good Agreement

Epoxy polymer concrete (EPC) has been widely used in civil engineering nowadays due to its excellent mechanical properties and advantages in processing. In this paper, a modeling study has been carried out on the flexural performance of EPC. Two classic micromechanics models, i.e. rule of mixture and Mori-Tanaka method, are introduced to predict the flexural strength of EPC with various epoxy resin contents. The comparison shows that the parallel model based on the rule of mixture attains a good agreement with the measured results when the epoxy resin content is sufficiently high to achieve strong adhesion between the aggregate and the epoxy resin. In contrast, the Mori–Tanaka method with the failure criterion dominated by the weakest phase fails to give acceptable prediction due to the unsuitability of its basic assumptions to EPC, particularly when the epoxy resin content is at relatively high levels.

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Polymer-Concrete Composites for the repair of concrete structures

MATEC Web of Conferences ◽

10.1051/matecconf/201819901006 ◽

2018 ◽

Vol 199 ◽

pp. 01006 ◽

Cited By ~ 2

Author(s):

Lech Czarnecki

Keyword(s):

Polymer Composites ◽

Construction Material ◽

Polymer Concrete ◽

Concrete Repair ◽

Concrete Mass ◽

Concrete Overlays ◽

Repair Materials ◽

European Standards ◽

Polymer Modified Concrete ◽

Short Time

In less than one century concrete has become the most widely used construction material over the world. In less than half of century it is difficult to imagine a concrete totally without polymers. An implantation of polymers into concrete has taken effect in the form of Concrete Polymer Composite: C-PC. Since then (1975) the development of new concrete classes have been ongoing: C-PC = PMC + PCC + PI + PC, where PMC Polymer Modified Concrete (polymer cont. < 1% concrete mass); PCC Polymer Cement Concrete (> 1% concrete mass); PIC Polymer Impregnated Concrete (3-8% concrete mass), PC Polymer Concrete (8-12% concrete mass). Over the time the role of polymers have been extended and it is covered by polymer with additional preposition: polymers on concrete (overlays, coatings, waterproofing and bounding materials). All those polymer composites have been found irreplaceable application in concrete repairing industry. It is enough to say that in ten parts of the European Standards, EN 1504, the category “polymer” can be found 73 times, and that is a proof of the big significance of this material in the repairs and protection of concrete. Just for comparison reason, the term “cement” appears only 59 times in all parts of the EN 1504. Indeed, if repaired concrete is higher class then repairing material should content more polymer. The justification belongs to the adhesion, which is a fundamental challenge for concrete repair. But also short time to exploitation readiness and many others polymer composites advantages are taken into consideration. In the paper the question: how polymers enhance concrete repair performance? is discussed. The repair rules and methods versus polymer repair materials will be considered.

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