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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]

Earthen plasters have been widely used in historical buildings such as grottoes, which have high historical, artistic, scientific, social, and cultural values. In order to study the influence of the material composition of plasters on its physical performance, a total of seven different types of earthen plaster specimens were made using Dengban clay and six admixtures (quartz sand, two types of vegetal fibers, and three types of hydraulic limes), and the surface water absorption properties, hygrothermal properties, surface strength (surface hardness, surface cohesion, and surface impact resistance), color difference, and radial shrinkage of all plasters were systematically investigated and compared. The results show that the addition of sand, vegetal fibers, and hydraulic limes all changed the surface water absorption, thermal conductivity, and water vapor permeability of plaster, and inhibit the radial shrinkage during the curing process. Compared to the other admixtures, sand had the least effect on the overall performance of plasters. Both types of vegetal fibers can greatly improve the impact resistance of plaster surface, but due to the formation of microcracks on the surface of the plaster with wheat straw fibers, its water absorption is much higher than that of the plaster with hemp fibers. The addition of three types of hydraulic limes changed the surface color of the plaster to some extent, and the water repellency of the plaster surface will be enhanced due to the carbonation of hydraulic lime. • The physical performance of seven types of earthen plasters was investigated. • The carbonation process enhances the water repellency of the plasters with hydraulic lime added. • The addition of vegetal fibers has greatly improved the impact resistance of the plaster surface. • The addition of hydraulic lime has an effect on the surface color (ΔE > 3). [ABSTRACT FROM AUTHOR]