The feasibility of a network materials utilization plan, with an emphasis on upcycling of material.

Abstract

In most countries, the road network is under the jurisdiction of an agency that is state-owned. Road agencies have the responsibility for the management, maintenance and development of the network through careful management of resources taking into consideration the financial obligation to manage public funds. Kasim et al. (2005) quantify that the cost to manage materials can range from 30-80% of the total construction costs. Because these costs are so high, they can determine the winning bidder. This gives rise to the need for the agency to reuse materials to their full potential and ensures the optimal salvage value of each material. The fall back design approach is to down cycle materials by recycling the existing pavement layers into lower-value layers. This design approach becomes questionable when the road agencies have a responsibility to optimally reuse the agency’s current assets. Due consideration of the financial obligation to manage public funds underpins the need to upcycle. Materials from the existing layer and materials required from external sources are managed in the Materials Utilisation Plan. The aim of the research is to investigate the opportunities of upcycling in a Materials Utilisation Plan. The objective of the research is to determine the factors influencing the specification of upcycling in the design of a Materials Utilisation Plan, to assess the effect of the identified factors and to produce a set of recommendations when implementing upcycling in a road upgrade project/program. Competitive tendering is the procurement process followed by potential design consultants, whereby the consultants, bid against each other to win a tender. The efficiency of the tendered resource becomes a major influential factor when competitive tendering is adopted. The consequence of such an environment is reduced rates and reduced hours with no additional capacity for any additional design improvements as described by Messner et al. (2018). The design for upcycling is the process of applying engineering judgment to assess the existing materials and determine its function in the new pavement. The use of engineering judgement is pinned on relevant design experience, the lack of adequate design experience to facilitate upcycling was a recurring theme throughout the research. The reliance on the catalogue design for pavements was emphasized as a major disbenefit to upcycling. Planning is the process of forethought into the project requirements. At the planning stage, key decisions are made. The design philosophy and design strategy is developed to meet the objective of the clients. The type of contract implementation is influenced by the decisions made at the planning stage. Technology advancement is the application of new, more accurate or more efficient use of scientific methods or equipment to improve on previous methods. The use of nanomaterial and nanotechnology in pavement design is gaining momentum. Design engineers are still to respond to the advancement in technology so that the industry can progress in the various methods of upcycling. There is a fundamental mismatch between the knowledge learned at tertiary level and what is being implemented in the industry. The data collected indicated a gap in knowledge relating to upcycling of materials, stemming from tertiary level education. The gap in knowledge was based on the undergraduate syllabus not including current industry practices. Upcycling is a fundamental concept and must be engrained at the tertiary level so that graduates can rely on the knowledge gained to enhance and improve on methods of upcycling. Exposure at tertiary levels promotes further research in the field.