Rheological properties of lignosulfonate intercalated layered double hydroxides modified bitumen before and after ultraviolet aging

Abstract

Rheological property of bitumen is closely related to the service life of bituminous pavement, which is mainly affected by temperature, vehicle load and ultraviolet (UV) ray. In this paper, lignosulfonate intercalated layered double hydroxides modified bitumen (LLMB) were researched by Fourier transform infrared (FTIR) spectrometer characterization, aging index and storage stability test. Meanwhile, rheological properties of LLMB before and after UV aging were investigated by temperature susceptibility, dynamic viscoelastic properties and rheological model analyses. The results showed that the introduction of lignosulfonate intercalated layered double hydroxide (LS-LDHs) could strengthen the anti-UV aging ability of bitumen more effectively and had better high temperature storage stability than layered double hydroxides (LDHs). From rheological performance measurement, LS-LDHs could weaken the temperature susceptibility of bitumen observably. Compared with pristine bitumen (PB), the values including loss tangent (tanδ), complex modulus (G∗) and rutting factor (G∗/sinδ) of LLMB got higher. According to rheological model analyses, the addition of LS-LDHs affected the models of bitumen hardly, but restrained instantaneous elastic, delayed elastic and viscous deformation. Therefore, LS-LDHs could enhance rigidity, high temperature performance and resistance to deformation of bitumen significantly. After UV aging, the rheological parameters variations and deformation arguments amplitudes of LLMB were lowest among PB, layered double hydroxides modified bitumen (LMB) and LLMB, which demonstrated that LS-LDHs improved the UV aging resistance of bitumen prominently.