Performance and Microstructure of Cold Recycled Mixes Using Asphalt Emulsion with Different Contents of Cement.

Yanhai Yang,Baitong Qian,Ye Yang

doi:10.3390/ma12162548

Abstract

Cold recycled mixes using asphalt emulsion (CRME) is an economical and environmentally-friendly technology for asphalt pavement maintenance and rehabilitation. In order to determine the optimum range of cement contents, the complex interaction between cement and asphalt emulsion and the effects of cement on performance of CRME were investigated with different contents of cement. The microstructure and chemical composition of the fracture surface of CRME with different contents of cement were analyzed in this paper as well. Results show that the high-temperature stability and moisture susceptibility of CRME increased with the contents of cement increasing. The low-temperature crack resistance ability gradually increased when the content of cement is increased from 0% to 1.5%. However, it gradually decreased when the content of cement is increased from 1.5% to 4%. Cold recycled mixes had better low-temperature cracking resistance when the contents of cement were in the range from 1% to 2%. The results of microstructure and energy spectrum analysis show that the composite structure is formed by hydration products and asphalt emulsion. The study will be significant to better know the effects of cement and promote the development of CRME.

Highlights

IntroductionAbout 60 million tons of old asphalt materials are produced in China every year
According to recent data, about 60 million tons of old asphalt materials are produced in China every year
Performance and microstructure of Cold recycled mixes using asphalt emulsion (CRME) with different contents of cement were investigated in this paper

Summary

Introduction

About 60 million tons of old asphalt materials are produced in China every year. These materials occupy a mass of land and pollute the environment. Highway agencies have attempted to reuse old asphalt materials to solve these critical issues [2]. One of the promising ways to recycle old asphalt materials is cold recycling technology [3]. The cold recycling technology has been largely used as surface and base course in a pavement system [2,4], which can make full use of plenty of old asphalt materials and reduce environmental pollution from old asphalt materials and greenhouse gases [5]

Objectives

Methods

Results

Conclusion