Effect and mechanism of salt erosion on performance of bitumen and asphalt mixtures(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2017年03期
- Page:
- 33-38, 46
- Research Field:
- 道路工程
- Publishing date:
Info
- Title:
- Effect and mechanism of salt erosion on performance of bitumen and asphalt mixtures
- Author(s):
- HUANG Xin-yan; SHA Ai-min; JIANG Wei; WANG Ya-ning
- 1. Key Laboratory for Special Area Highway Engineering of Ministry of Education, Chang’an University, Xi’an 710064, Shaanxi, China; 2. Guangxi Communications Investment Group Co., Ltd., Nanning 530022, Guangxi, China; 3. China Railway First Survey & Design Institute Group Co., Ltd., Xi’an 710043, Shaanxi, China
- Keywords:
- road engineering; salt erosion; asphalt mixture; performance; acceleration test
- PACS:
- U414.1
- DOI:
- -
- Abstract:
-
It is possible that the sea salt particles existed in the rainfall, the sea fog and the atmosphere in coastal areas can erode the pavement materials. Therefore, this paper studied how the chemical salt in the seawater affected the performances of asphalt and mixtures as well as the mechanism. Based on the main technical indicators and component measurements of asphalt, the effects of seawater and its various types of salt on the main technical indicators and components of asphalt were analyzed. The high temperature stability, low temperature performance, moisture sensitivity and fatigue performance under salinity and high temperature coupling were investigated via the salt erosion and cycling acceleration simulation test. Additionally, the decay mechanism of asphalt mixtures under salinity and high temperature were also been discussed on the basis of the results of contact angle test and laboratory test. The results show that the content of aroma and saturated fraction in asphalt component is decreased and the asphaltic content is relatively increased after the erosion of different types of chemical salt, while the softening point is increased and the penetration is reduced on the generate indicators of asphalt. In all kinds of eroded environment, seawater has the greatest influence on the penetration and softening point of asphalt binders, followed by NaCl solution, MgCl2 solution, KCl solution, NaSO4 solution, air and pure water. Seawater is not only easier to infiltrate the aggregate than pure water, but also easier to penetrate the interface of asphalt and aggregate, thus reducing asphalt/aggregate interfacial bond strength. Meanwhile, the volume of expansion will happen in the crystallization process of the soluble salt, resulting in crystallization pressure. The high temperature stability, low temperature crack resistance, moisture sensitivity, and fatigue performance of asphalt mixtures will be degraded in different degrees because of these integrated factors.
Last Update: 2017-06-06