Analysis of Aggregate Morphological Characteristics for Viscoelastic Properties of Asphalt Mixes Using Simplex Lattice Design

Abstract

Morphological characteristics of aggregates have direct impacts on performances of asphalt mixes. This paper aims to investigate the effects of the morphological characteristics of fine and coarse aggregates on the high-temperature viscoelastic properties of asphalt mortars and mixtures. For this purpose, an experimental proportion scheme was designed for asphalt mixes prepared with three different types of aggregates (basalt, andesite and pebble/river sand) based on the simplex lattice design (SLD) method. Three morphological parameters were chosen to characterize shape, angularity and texture of aggregates. Afterwards, the uniaxial compression creep test was conducted for asphalt mixes and the high-temperature viscoelastic properties were obtained based on Burgers model. The effects of fine and coarse aggregates on the viscoelastic properties are analyzed through asphalt mortars and mixtures, respectively. The results showed that aggregate morphological characteristics correlate with the high-temperature viscoelastic properties of asphalt mixes, especially for fine aggregates. Aggregates with complex morphological characteristics are conducive to improving the deformation recovery and anti-deformation of asphalt mixes. Furthermore, coarse aggregates can enhance the anti-deformation of asphalt mixture effectively due to its skeleton effect.

Influence Analysis and Optimization for Aggregate Morphological Characteristics on High- and Low-Temperature Viscoelasticity of Asphalt Mixtures

“…Asphalt mortar consists of asphalt, mineral filler and fine aggregate passing through 2.36 mm sieve size, and its gradation was similar to AC-13. The detailed sample preparation process was given in a previous study [ 23 ]. After determining asphalt contents, each component content in asphalt mortar and mixture could be calculated according to the densities of aggregate and asphalt, which are listed in Table 6 .…”

“…The image processing technique is employed to process (image denoising and enhancement) these color images, in which the images of coarse and fine aggregate were obtained by scanner and stereo microscope (Opt Vision Technology Co., Ltd., Dongguan, China). Then, the morphological characteristics of aggregates, including shape, angularity, and texture characteristics, can be obtained according to previous study [ 23 ]. Roundness, perimeter index, and erosion-dilation area ratio were used to represent the shape, angularity, and texture characteristics of aggregates, which were defined and could be measured in previous study [ 23 ].…”

Further Investigation on Damage Model of Eco-Friendly Basalt Fiber Modified Asphalt Mixture under Freeze-Thaw Cycles

“…Additionally, basalt fiber was obtained from Jiuxin Basalt Industry Co., Ltd. (Changchun, China). The detailed physical properties of the aggregates and basalt fiber have been given in the previous study [5]. Table 1.…”

“…Asphalt pavement has been widely used in flexible pavement constructions in a rapidly growing trend [1][2][3][4]. Asphalt mixtures are generally considered complex porous materials including asphalt, aggregates, and filler, as well as voids [5][6][7]. However, due to some environmental factors, there are many distresses in asphalt pavements such as spalling, crumbling, pavement potholes, etc., especially in seasonally frozen regions [8][9][10].…”

“…Step ( Figure 1. Gradation of asphalt mixture used in this study [5]. Figure 2 gives a detailed description of the freeze-thaw cycles in this study, in which the real simulation is shown in Figure 2a, and the one-time freeze-thaw cycle in the laboratory is shown in Figure 2b.…”