Performance Evaluation of Flexible Pavement by Using CNT and Plastic Waste as Admixtures

Abstract

Interstate highway construction is proceeding rapidly in Pakistan. Rutting resistance is a growing concern due to the proliferation of flexible pavements used in the construction of roads and highways. To go past this, we need to figure out ways to fix these issues. The current economic climate necessitates the use of locally sourced, inexpensive materials. The rutting of Flexible Pavements can be mitigated by using admixtures in the bitumen, such as Cabon Nano tubes and Plastic Waste. To learn how using Carbon Nano tubes and plastic waste by Wheel tracking device affects its Dynamic Stability and Rutting resistance, several tests should be conducted. Waste plastic is a readily available, low-cost resource. To make the modified asphalt mix, wet process mixing of bitumen (60/70 penetration grade) and Marble dust at a high temperature (160-165) is followed by mixing of aggregates. The following percentages of plastic waste and CNT were used to create the modified asphalt concrete samples: (0.1 to 0.4). Marshall Mix design (ASTM D6926) was used to create modified and unmodified Samples, with NHA Class B gradation. To ensure conformance with NHA standards, bitumen (60/70 penetration grade) and aggregates (Margalla aggregate) were tested before samples were prepared. Using Marshall Mix design (ASTM D6926), the optimal binder content (OBC) was determined to be 4.5%; however, OBC 4.8% (derived from earlier research work at ESDev VI 2017) is used in the manufacture of both standard and customised samples. The effectiveness of the changed mixes was evaluated by a battery of tests, including Rutting resistance and Dynamic stability. Using a wheel tracking system, this study compared the samples' dynamic stability and rutting when made with varying percenttages of plastiic waste and carrbon nanotubez (ranging 0.1 to 0.4%). The results reveal that compared to plastic and traditional bitumen, adding carrbon nanotubez greatly enhance the dynamiic stabillity of asphaalt.