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Road distress results in high maintenance costs. However, increased understandings of asphalt behaviour and properties coupled with technological developments have allowed paving technologists to examine the benefits of introducing additives and modifiers. As a result, polymers have become extremely popular as modifiers to improve the performance of the asphalt mix. This study investigates the performance characteristics of epoxidized natural rubber (ENR)-modified hot-mix asphalt. Tests were conducted using ENR–asphalt mixes prepared using the wet process. Mechanical testing on the ENR–asphalt mixes showed that the resilient modulus of the mixes was greatly affected by testing temperature and frequency. On the other hand, although rutting performance decreased at high temperatures because of the increased elasticity of the ENR–asphalt mixes, fatigue performance improved at intermediate temperatures as compared to the base mix. However, durability tests indicated that the ENR–asphalt mixes were slightly susceptible to the presence of moisture. In conclusion, the performance of asphalt pavement can be enhanced by incorporating ENR as a modifier to counter major road distress.

Traffic Network Study Tool Version 7F software (TRANSYT-7F) is one of the traffic programs used in analyzing and evaluating the performance of road junction networks based on simulation and signal timing optimization. This paper describes the study conducted during evening peak periods in two cities in Malaysia: Shah Alam and Petaling Jaya. The main objectives of this study are to evaluate and compare the performance of road junction networks in Petaling Jaya and Shah Alam cities using TRANSYT-7F software, the performance of road networks such as; Total Travel Times (TTT), Average Delays (AVD), System Wide Travelling Speed (SWTS), Operating Cost (OPC), Level Of Service (LOS), Fuel Consumption (FUC) and Performance Index (PI). The results obtained have shown a clear indication that the software is able to improve the performance of road junction networks in Shah Alam and Petaling Jaya. TRANSYT-7F had increased the SWS in rush hours in various study fields, where the percentage of improvement in the Shah Alam city is up to 23% as well as the Petaling Jaya city is up to 41%. On the other hand, TRANSYT-7F had reduced the FUC up to 33% in Shah Alam and 54% in Petaling Jaya. Moreover, a reduction of PI is nearly 16% and 33% in both cities respectively.

Purpose The purpose of this study is to explore the multifaceted challenge of managing construction and demolition waste within the context of the Jordan construction industry. Design/methodology/approach Using data sourced through desk research, interviews and questionnaires, this study examines the principal causes of increased volumes of construction and demolition waste, as well as the obstacles to both developing and implementing better waste management strategies. Findings This study identifies multiple causes of issues related to waste management and barriers to developing and implementing solutions and concludes by recommending a holistic approach to this multifaceted problem. A lack of adequate construction waste management infrastructure, regarding both physical facilities and regulations, was highlighted as the key challenge. Social implications The accumulation of waste that results from construction and demolition activity, and activities characterized by unsustainable utilization of raw materials and inefficiency are a global issue. The challenge of effectively managing construction waste is importantly tied to factors including the availability of the necessary infrastructure; economic conditions; and the scarcity of skilled laborers, among others. Originality/value This study focuses on the Jordan construction industry, which is so far not very well researched. By building upon previous studies, this study supports further research to illuminate the causes of waste and the barriers to better management, an issue that is not only a pillar of progress at the country level but also key for a sustainable development in general.