Tri-Axial Testing of Rubberized Concrete - Coursework Example

Name: Course: Title: Tri-axial Testing of Rubberized Concrete Date: Task: Tri-axial Testing of Rubberized Concrete Abstract Due to the increased in the number of vehicles on the road, the volumes of tyres waste are increasing every year. Since these wastes are non biodegradable, it poses a severe health and environmental risks. The besides other reuse of these wastes, recycling rubber as a partial replacement of aggregate has a potential to produce a lasting positive effect on the performance of the concrete. This study will utilize waste rubber tyres in the partial replacement of coarse aggregate to construct a concrete pavement. An experiment will be performed to determine the strength of the concrete with grounded rubber waste. The failure characteristics and behavior of rubberized concrete will be analysed. Other factors such as the particle size and the curing duration will also be assessed. Introduction The rising number of vehicles on roads of developing and industrialized nations generates a huge volume of used tyres each year. The tyres are the most problematic sources of waste, due to their durability and large production volume; resulting in an increasing environmental problem in the 20-centuries cities. Therefore, there is a need to investigate ways through which this waste can be reused. One of the solutions is to reuse scrap tyres in the production of concrete, whereby the tyre rubber granules are used a partial replacement to aggregate. This will save the natural resources that are increasingly becoming scarce. This paper explores the feasibility of partial replacement of aggregate by waste tyre granules in the concrete, using the common procedure and equipment. This is achieved by performing tests to analysis mechanical and physical properties of the concrete that contains the rubber waste. The tests include analysis of the factors such as the effects of rubber of the strength of the concrete, the sizes of the granules, curing time on the workability of the concrete, the compressive strength, the density, modulus of elasticity, tensile strength, and the stress-strain characteristics. This method has been used to provide solutions for different quality problems in different parts of the world and in spite of some drawbacks; in most cases it has exhibited better performance of road’s pavement (Lo, 2013; Ganiron, 2014). This study involves investigation of the existing specifications and technologies associated with handling, production and storage of tyre rubber modified concrete mixture on the application on road pavement. Since this technology is has not been adopted fully, mainly due to lack of information, lack of trained personnel and lack of policies to support this technology, the current work aims to provide up to date information to elucidate on the issues and benefits related to this technology. Previous studies has reported that the rubberized concrete demonstrate improved performance in absorption of vibrations and shocks. It is lighter than the conventional concrete and has better noise control. In addition, it has superior freeze – thaw properties that results in less cracking, contraction, expansion and shrinkage compared to the conventional concrete mixture. The main disadvantage of using this technology is the reduction of the concrete strength (Aiello & Leuzzi, 2010). Brief Review of Literature The reuse of tyre waste as an additive for the concrete mixture has been investigated for many years (Yilmaz & Degirmenci, 2009). The studies have shown that waste tyres can be used successfully in the construction of roads. Although the use of rubberized concrete is promising, considering the environmental benefits, it has not been used widely due to the fact that its cost and performance have not been studied comprehensively. Since the waste tyres take a very long time to decompose, it can be found almost everywhere (Ganiron, 2014). Despite the fact that the waste tyres can be reused, the government has not allocated enough budget for its research. Currently, the volume of waste is continuously increasing, posing a serious environmental problem. Less than 205 of this tyre waste are rethreaded or reused, leaving over 85% of the scrap tyres to be managed. Many alternatives have been proposed by the researchers to solve the problem. One of the solutions is to use them in the concrete mix for the construction of pavement (Ganiron, 2014). A research by Bakari et al. (2007) on rubberized concrete showed that the compressive strength was reduced, as the waste tyres rubber behave like voids in the matrix. This is due to the weak bonds between the waste rubber tyres and the concrete matrix (Bakari et al.2007). Mavroulidou & Figueiredo (2010) concluded that in spite of lower values of mechanical properties, the rubberized concrete has a potential to produce a concrete product with better performance, which demonstrate for developing a way of reuse of tyres (Mavroulidou & Figueiredo 2010). Waste tyres rubber can be integrated into the concrete mixture through two different ways, which include dry and wet process (Ganiron, 2014). In dry process, grounded rubber is used as an additive in the concrete mix, while in wet process, crumb rubber is used. In dry process, the rubber granules produced is used to substitute a small portion of aggregate in the ration of three percent of the total aggregate weight. The rubber granules are mixed with the aggregate before adding the cement. In some cases, the rubber particles are mixed with hot asphalt concrete (Khatib, 2009). The dry process that has been applied successfully originated from Sweden. In the process, rubber granules with sizes ranging from 2 mm to 4 mm are added in the mixture in the ratio of 1 to 3 % of the total aggregate weight. The air voids is expected to be approximately 3% (Lo, 2013; Ganiron, 2014). A dry process that was developed in 1990’s used both fine and coarse crumb rubber to produce hot mixture. The outcome showed improved performance due to better binding effect. The sample can be pretreated with a catalyst to produce optimum swelling (Khatib, 2009). This technology is more effective in construction of pavement in areas with high temperatures. The rubber particles can protect the pavement against deformation because of the viscous characteristics of the concrete and other effects that results from heating like bleeding rutting. In addition, the material can reduce the noise level because of the vibrating pavement structure. Studies have shown that rubberized concrete reduces the noise level from 4 to 10 dB, and thus can be valuable for the construction of pavement in cities (Ganiron, 2014). Aim and Objectives The current effort is focused on identification of the potential techniques for application of waste tyres in the construction work. In this context, the aim of this project is to use the experimental results to develop uniaxial/triaxial stress-strain relationship for rubberized concrete with different rubber content. In order to achieve this aim, this study will: 1) Investigate the strength of rubberized concrete 2) Investigate the effect of confinement on the stress-strain response of rubberized concrete 3) Study the effect of strain-rate (load-rate) on the stress-strain behaviour of rubberized concrete 4) Study effect of rubber content dissipation and volumetric response 5) Develop expressions to predict the stress-strain response of rubberized concrete as a function of rubber content and confinement pressure. A total of 56 concrete cylinder specimens (63 mm x 126 mm) will be prepared and tested under compression. The cylinders will be prepared in UniSa but will be tested in Adelaide Uni. References Aiello, M. A., & Leuzzi, F. (January 01, 2010). Waste tyre rubberized concrete: properties at fresh and hardened state. Waste Management (new York, N.y.), 30. Ganiron, T. U. (January 01, 2014). Waste tire as an asphalt cement modifier for road pavement. International Journal of U and E Service, Science and Technology, 7, 5, 181-194. Lo, P. D. (December 01, 2013). Recycled Tyre Rubber Modified Bitumens for road asphalt mixtures: A literature review. Construction and Building Materials, 49, 1, 863-881. Khatib, J. M. (2009). Sustainability of construction materials. Cambridge [u.a.: Woodhead Publ. Mavroulidou, M., & Figueiredo, J. (December 01, 2010). Discarded tyre rubber as concrete aggregate: A possible outlet for used tyres. Global Nest Journal, 12, 4, 359-367. Yilmaz, A., & Degirmenci, N. (January 01, 2009). Possibility of using waste tire rubber and fly ash with Portland cement as construction materials. Waste Management (new York, N.y.), 29, 5, 1541-6. Read More