Performance Deterioration of Asphalt Mixture under Chloride Salt Erosion

Fuyu Wang,Wensheng Wang,Xingyuan Qin,Weichen Pang

doi:10.3390/ma14123339

Abstract

In order to ensure smooth traffic and driving safety, deicing salt or snow melting agents are usually adopted to solve the problem of traffic jams and prevent pavement surfaces from freezing. The objective of this present study is to investigate the performance deterioration evaluation of asphalt mixture under the chloride salt erosion environment. Five chloride salt solution concentrations were designed and the uniaxial static compression creep test, low-temperature IDT test, freeze-thaw splitting test, and freeze-thaw cycle test were carried out for asphalt mixtures (AC-16) soaked in chloride salt solution. Results showed that with the increase in chloride salt solution concentration, the high-temperature stability, low-temperature crack resistance, and water stability of the asphalt mixture decreases. Moreover, the high-temperature stability, low-temperature crack resistance, and water stability of the asphalt mixture show a decreasing trend under different chloride salt solution concentrations following the negative cubic polynomial function. Based on the viscoelastic analysis, chloride salt solution could reduce the ability of the asphalt mixture to resist instantaneous elastic deformation and permanent deformation, and this influence will become more obvious with the increase in chloride salt solution concentration. In addition, the salt freeze-thaw cycle test indicated that in the early stage of freeze-thaw cycles, the splitting tensile strength of the asphalt mixture decreases rapidly, then tends to be flat, and then decreases rapidly. This study explores the performance damage law of asphalt mixture under salt corrosion, and the analysis results of this study could provide some references for the chloride salt dosage in the snow melting project while spreading deicing salt.

Highlights

In northern China, the temperature is very low in winter; the duration of freezing is long, continuous snowfall or heavy snow leads to traffic jams on expressways and urban roads [1,2,3,4,5]
The creep curves are almost perpendicular to the abscissa axis and an approximate straight line. This is as asphalt mixture, as a kind of viscoelastic material, is subjected to vertical load, showing instantaneous elastic performance in a short time, and has a high deformation rate
The asphalt mixture specimens soaked with different snow melting chloride salt concentrations were taken as the research object

Summary

Introduction

In northern China, the temperature is very low in winter (the average temperature is about −15 ◦ C); the duration of freezing is long, continuous snowfall or heavy snow leads to traffic jams on expressways and urban roads [1,2,3,4,5]. In order to ensure smooth traffic and driving safety, many road projects adopt the method of spreading deicing salt, a snow melting agent with the function of quick deicing and snow melting, to solve the problem of traffic jams and prevent pavement surfaces from freezing [9]. The main working principle of spreading the deicing salt snow melting agent is based on the freezing point reduction theory [14,15]. When chloride salts are added into water, the surface of water is occupied by chloride salt ions, resulting in relatively small vapor pressure of water compared with ice. it is necessary to lower the temperature to make the vapor pressure of ice equal to the vapor pressure of water, resulting in a decrease in the freezing point. Asphalt mixture is a multi-phase mixture system composed of coarse and fine aggregates, fillers, and asphalt binders [8]

Objectives

Methods

Results

Conclusion