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Asphalt is one of the primary materials that are extensively used by the pavement industry throughout the world. Its behaviour is highly dependent on the amount of loading and the level of temperature it is exposed to. Asphalt has been modified in the past with different additives to improve its high- or low-temperature properties. In Pakistan, temperature remains high for most of the time of the year; hence, asphalt binders with less susceptibility to higher temperatures are preferred for flexible pavements. Acids, polymers, fibers, and extenders have been used by the researchers to improve high-temperature performance of asphalt mixture. In the present study, a bio material derived from the animal waste, named as bone glue (BG), has been used with the 60/70 penetration grade binder in dosages of 3%, 6%, 9%, and 12% by weight of asphalt binder. The bone glue is produced from a sustainable source. It is a cost-effective and eco-friendly material. Moreover, it produces a durable and nonhazardous asphalt composite. The influence of addition of bone glue on asphalt binder was evaluated using different testing techniques which include consistency tests, rheological analysis, and adhesion tests. Furthermore, different performance tests were conducted on bone glue-modified asphalt mixtures. Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) analysis were carried out to ensure the homogeneity and proper mixing of bone glue in asphalt binder. The results from the tests reveal that bone glue stiffens the asphalt binder hence enhancing its high temperature performance. Bone glue dosage of 9% by weight of the binder was found to be the optimum dosage based on the rheological and performance analysis.

Asphalt mixture that is used for the construction of flexible pavements is mainly composed of two constituents i.e. bitumen and aggregate. Sturdy adhesion among bitumen and aggregate is the sign of durability of asphalt pavements. Adhesion is considered as one of the most important factors for sustainable asphalt pavement. This is the motive why its miles utmost important to deeply understand the phenomenon of adhesion considering the effect of alternate in temperature, moisture conditions. In this study softer binder 80/100 was selected that has less adhesion compared to hard pen grades. Limestone aggregates which is commonly used for the construction of asphalt pavements has also been selected. Two types of modifiers (Zeolite and Paraffin Wax) were selected because of the extensive use in asphalt foaming and the polymer modified asphalt mixtures as temperature reducing agent. To investigate the strength of adhesive bond, Bitumen Bond Strength (BBS) was performed at different temperatures, in dry, and wet conditions. To quantify the effect of modifiers on penetration grade and softening point conventional testing is performed. For performance grading, the PG test was performed using Dynamic Shear Rheometer. The comparisons were developed among pull of tensile strength at dry and after 72hrs water conditioning while preserving the temperature at 25 .To check the effect of temperature BBS is performed at 15 . The results illustrate that 2% zeolite shows best results in terms of adhesion and performance grade while Paraffin wax has less adhesion and poor performance grade.

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