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Volatile organic compound (VOC) emissions are becoming an increasingly significant issue because of the increasing demand for bitumen in road engineering. This study attempted to develop a type of fume-suppressed bitumen with good comprehensive performance. Initially, 1, 2, and 3% organic montmorillonite and 2, 3, and 4% waxy warm-mix agents were utilised to modify bitumen. Subsequently, the fume suppression and physical and construction performances of the modified bitumen were evaluated, and the modified bitumen with the best comprehensive performance was determined. On this basis, constant- and variable-temperature heating modes were designed to verify the fuel suppression performance of the modified bitumen thoroughly. Finally, the modification mechanism of modified bitumen was investigated via atomic force microscopy. The results indicate that the modifier had the greatest impact on the ductility of the modified bitumen in terms of its physical performance. Although waxy warm mixed agents increase VOC emissions, organic montmorillonite can inhibit this effect. The modified bitumen, composed of 2% organic montmorillonite and 2% waxy warm mix agent, has the best comprehensive performance, with a 40.6% emission reduction rate under constant temperature heating mode and 46.4–28% range from 200 ℃ to 120 ℃ under another mode. The waxy warm mix agents and organic montmorillonite-modified bitumen developed into continuous and dispersed phase systems, respectively, leading to variations in the modified bitumen's physical performance and VOC emission capacity. In contrast, the composite-modified bitumen exhibited a two-phase structure with the surface morphology of an 'egg tray'. This unique structure enhances the heating surface area and facilitates heat conduction, improving the bitumen performance during construction. [Display omitted] • Consideration was given to the VOC emission reduction effect caused by the decrease in viscosity of bitumen. • The efficacy of fume suppression asphalt was verified in two heating modes. • A fume suppression asphalt with commendable comprehensive performance was designed. [ABSTRACT FROM AUTHOR]

• The harmless treatment and utilization of waste tires is promoted. • Bitumen was composite-modified by TPO and TPCB. • The design and preparation parameters of TPO/TPCB-MB were determined. • TPO can balance the components and recover the TPCB's effects on the properties of bitumen. • Road properties of TPO/TPCB-MB and its mixture were not worse than 70# bitumen. Waste tires are produced in large quantities and cause serious pollution. Moreover, it is challenging to dispose of waste tires safely. Pyrolysis treatment is an economic, environmentally friendly, and high-recovery-efficiency solution, but the recycling applications of pyrolysis products, such as pyrolysis carbon black (TPCB) and pyrolysis oil (TPO), have not been widely studied. In this study, TPO and TPCB were applied to composite-modify 70# base bitumen. The modification mechanism of TPO/TPCB-modified bitumen (TPO/TPCB-MB) was studied by Fourier transform infrared spectrometry (FTIR), gel-permeation chromatography (GPC), X-Ray diffraction (XRD), and scanning electron microscopy (SEM). The physical performance and rheological performance of the bitumen with and without TPO/TPCB were investigated to determine the design and preparation parameters of TPO/TPCB-MB and investigate TPO/TPCB's effects on the technical performance of bitumen. In addition, the road performance of TPO/TPCB-MB concrete was extensively studied. In the results, no large agglomeration phenomenon was observed between the TPCB particles. Furthermore, the molecular weight of TPO was much lower than that of 70# bitumen, indicating that TPO can increase the light components of bitumen. TPCB and TPO mixed with the bitumen in a physical manner, and the multi-layer spacing of TPCB remained basically unchanged. The TPO/TPCB was also shown to have good thermal and structural stability. TPO and TPCB, moreover, provided component balance and powder hardening effects in the TPO/TPCB-MB. No significant difference was observed between the technical performance of the 70# bitumen and the 0.9% TPO + 15% TPCB-MB. The water stability, low-temperature, and anti-fatigue performance of the TPO/TPCB-MB mixture was significantly better than that of the 70# bituminous mixture. Meanwhile, the high-temperature performance showed no obvious difference. Therefore, TPO was found to balance TPCB's oppositive effect on the performance of bitumen and its mixture. The composite modification of bitumen with TPCB and TPO thus represents a harmless treatment and alternative use for waste tires. [ABSTRACT FROM AUTHOR]