Improving rubber concrete by waste organic sulfur compounds

Abstract

In this study, the use of crumb tyres as additives to concrete was investigated. For some time, researchers have been studying the physical properties of concrete to determine why the inclusion of rubber particles causes the concrete to degrade. Several methods have been developed to improve the bonding between rubber particles and cement hydration products (C-S-H) with the hope of creating a product with an improvement in mechanical strength. In this study, the crumb tyres were treated with waste organic sulfur compounds from a petroleum refining factory in order to modify their surface properties. Organic sulfur compounds with amphiphilic properties can enhance the hydrophilic properties of the rubber and increase the intermolecular interaction forces between rubber and C-S-H. In the present study, a colloid probe of C-S-H was prepared to measure these intermolecular interaction forces by utilizing an atomic force microscope. Experimental results showed that rubber particles treated with waste organic sulfur compounds became more hydrophilic. In addition, the intermolecular interaction forces increased with the adsorption of waste organic sulfur compounds on the surface of the rubber particles. The compressive, tensile and flexural strengths of concrete samples that included rubber particles treated with organic sulfur compound also increased significantly.

Properties of rubberized concrete modified by using silane coupling agent and carboxylated SBR

“…The significant loss of strength is mainly attributed to the hydrophobic nature of untreated rubber, which creates a weak interfacial bond between the rubbers and cement paste. The surface modification of rubbers is considered to be one of the most effective methods to improve the interface bonding (Albano et al, 2005;Dong et al, 2013;Chou et al, 2010). Albano (2005) observed improvement in the compressive and splitting tensile strengths of rubberized concrete containing NaOH and silane pre-treated waste M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT tire rubbers as a fine aggregate replacement material.…”

Properties and durability of concrete containing polymeric wastes (tyre rubber and polyethylene terephthalate bottles): An overview

“…Oiknomou et al [38] mentioned that the use of SBR latex enhances the adherence between the rubber waste and the cement paste. Chou et al [39] suggest the pretreatment of crumb rubber with organic sulphur stating it can modify the rubber surface properties increasing the adhesion between the waste and the cement paste. Investigations about rubber waste concrete show a compressive strength loss with waste content increase.…”

Properties and durability of HPC with tyre rubber wastes

“…Some research has already been conducted on the used of waste tyre as aggregate replacement in concrete showing that rubber aggregates reduces concrete workability [4] and compressive strength [5]. The strength loss is much more profound when coarse rubber aggregates are used which is due to the low adhesion between these wastes and the cement paste, but several authors recommend different treatments to enhance the adhesion of the rubber aggregates [6][7][8]. Previous investigations also show that concrete composites containing tyre rubber waste are known for their high toughness [9], meaning that they are specially recommended for concrete structures located in areas of severe earthquake risk and also for the production of railway sleepers.…”