Geotechnical Engineering: Alternative Aggregates in Asphalt - Case Study Example

Table of Contents Overview 2 Benefits of Alternative Aggregates in Asphalt 3 Problems of Alternative Aggregates in Asphalt 4 References 6 Overview Geotechnical engineering is a branch of civil engineering in the field of science, which is an analysis of the mechanism of different forms of soils and rocks. Geotechnical engineering is about studying the ideas and techniques in designing and constructing foundations, embankments, tunnels, and roadways among others that are built with rock and soil. It has application in different sphere that include mining, military and petroleum among others that are associated earth materials. A geotechnical engineering project is required to be conducted on the basis of certain procedures with the aim of having an appropriate understanding about material properties (Day & Hulme, 2004). Alternative aggregation is identified as a procedure of using recycled or secondary materials as alternative in the construction industry. Alternative aggregation in asphalt is utilized for building pavements has different benefits as well as problems formed during recycling of waste disposal of plastics and rubber from scrap tyres. Alternate aggregation in asphalt also leads to low cost and abundance in developing pavement network. Additionally, alternative aggregation is also identified to ensure safety and strengthens pavements, which enhances the production scale in asphalt for better profitable growth if produced by construction industry. The abundant availability of plastic and rubber are used as alternative aggregation in asphalt resulting in developing pavements at an economical cost (Day & Hulme, 2004). On the other hand, the compositions of asphalt with the use of different alternatives may lead to physical and chemical changes in various physical properties while building pavements. Additionally, aggregation of alternative is identified to form moisture, which adversely affects the structural process of pavements resulting in appropriate quality of construction projects. The process of forming asphalt for pavements with the assistance of alternative aggregates is also identified to affect environment for emitting stinking fumes (Day & Hulme, 2004). The study is about analysing benefits and problems associated with geotechnical engineers implementing alternative aggregation of asphalt for developing pavements by recycling the waste disposal of plastics and rubber procured from scrap tyres. Benefits of Alternative Aggregates in Asphalt The alternative aggregation in asphalt is set by the government to achieve the sustainability target by replacing natural aggregates with the use of waste disposal for structuring pavements. In this respect, geotechnical engineers using alternative aggregation in asphalt utilized for forming pavements leads to reduction of waste disposal. The use of alternative aggregates in asphalt will aid in having adequate supply of pavements for the road construction industry. Alternative aggregation in asphalt is identified to ensure that pavements required for the construction purposes of roads and tunnels are of better quality. The ‘Waste Resource Action Programme and Department of Trade and Industry’ has provided fund to the ‘Partners in Innovation’ (PIL) for asphalt with a mixture of rubber procured from scrap tyres and plastic wastes. Excessive and low cost plastic waste can be procured through shredder waste, which can be available in scarp cars and plastic. In asphalt, aggregation of plastic and rubber also deliver lower cost in comparison landfill. Another important constituting material for developing alternate aggregation in asphalt for building pavements is rubber crumb, which is generated by recycling rubber wastages. In this respect, alternative aggregates in asphalt aids in ensuring that road and tunnel construction activities are conducted with cost effectiveness and safety pavements in areas relating to playground for children (Day & Hulme, 2004). The plastic recycling process such as thermoplastic is used in the generation of alternative aggregates to strengthen the mixture of asphalt, which is essential for building the pavements. Wastages are procured through train carriage bodies, caravans, electrical housings and vehicle bodies for forming asphalt. In this regard, the use of wastage in the production of asphalt has led to the abundant availability of mixture in asphalt. Subsequently, geotechnical engineers with the use of alternative aggregation of asphalt are able to construct bridges, highways and pavements in a cost effective manner. Europe has also produced mixture of asphalt named ‘Colsoft’, which reduces noise in motorways and bypasses. In the road surface, the gaps of 6mm or 10mm are filled with small particles of rubber crumb, which reduces noise up to 5db (Hassan & et. al., 2004). As per US Environment Protection Agency (EPA), every year 215 million tons solid waste generated by Construction and Demolition Waste (C&DW) are recycled and added in mixture for the production of asphalt, which are utilized in various giant projects such as road construction and renovation of buildings among others(Khalaf, n.d.). In this respect, the use of alternative aggregates in asphalt is recognised as an effective procedure of building pavement network in a cost effective and adequate manner, which also aid in preserving natural resources to a large extent. Problems of Alternative Aggregates in Asphalt The production of asphalt from alternative aggregates has certain issues. The aggregation of rubber and plastic for the production of asphalt is identified to raise problem in building the pavement composition and environment consciousness. In the UK, every year around 4 million ton (Mt) of plastic waste is generated from approximately 200,000 ton of plastic in the recycling process. In this respect, abundant plastic not used in the recycling process is considered as wastage because of lack of techniques to sort waste based on its generic types. Shredder waste is easily available and can be procured at a low cost utilized for constructing pavements, which is spread in huge areas owing to which it is difficult to have required resources from one place. Alternative aggregates also develop problems such as generation of excess heat and oil when rubber crumb is mixed with asphalt, which creates negative impact for pavements used in road and construction industry. Geotechnical engineers resolve the problem of excess heat generation before manufacturing the pavements by conducting tests with the assistance of which 150 degree centigrade is managed to be kept within 10 - 15 degree centigrade of air temperature (Day & Hulme, 2004). Asphalt consumes abundant mixture of hydrocarbons, metals and gases such as oxygen and nitrogen, which may result to different chemical compositions. The chemical compositions may lead to changes in various physical properties of the mixture used for producing pavements through alternative aggregation of asphalt. Alternative mixture of asphalt results is forming moisture, which damages susceptibility of pavements resulting in negatively affecting the structural process in construction operations (The National Academics, 2012). The polymer industry faces problem in relation to storage in pellet agglomeration, which creates hindrances in forming effective pavements from alternate aggregation of asphalt. Problem of emission of pungent fumes due to burning of rubber and plastics has an adverse effect on the environment. In aggregation of asphalt, dust of hydrated lime cannot be effectively preserved in baghouse, which also raise the problem of emission leading to wastage (King, n.d.). References Day, D. & Hulme, A., 2004. JMU Pavement Conference. Alternative Aggregates in Asphalt and Concrete, pp. 24-25. Hassan, K. E. & et. al., 2004. Development of Asphalt and Concrete Products Incorporating Alternative Aggregates. Unpublished Project Report, pp. 1-43. Khalaf, F.M., No Date. Recycling of Clay Bricks as Aggregate in Asphalt Concrete. School of the Built Environment, pp. 1-10. King, G., No Date. Asphalt Pellets. An Alternative Delivery System for Asphalt Products, pp. 1-17. The National Academics, 2012. Transportation Research Circular. Alternative Binders for Sustainable Asphalt Pavements, pp. 1-84. Read More