介绍

在美国西北太平洋地区，因钉胎磨损引起的路面龟裂是一个严重问题，每年给俄勒冈州、华盛顿州和阿拉斯加的沥青和波特兰水泥混凝土道路造成数百万美元的损失。根据阿拉斯加大学安克雷奇分校的一项研究，“到2019年，阿拉斯加在未来20年内因使用钉胎而造成的道路损害预计总成本将达到2.032亿美元。”

挑战

In Anchorage, Alaska, the studded tire rutting issues are especially prevalent due to high traffic. According to Drew Pavey, State Pavement Management Engineer for the Alaska Department of Transportation & Public Facilities (DOT&PF), “In some areas, we are seeing average wear rates of an eighth-inch (3 mm) a year.”

决议

Attempting to mitigate the studded tire damage, the Alaska DOT&PF decided to test Kraton’s high-performance, polymer-based HiMA™ in the wearing course mixtures. The project took place in Anchorage, where a PG 64E-40 HiMA binder was used in a Superpave mix incorporating hard aggregate. The HiMA mix was placed on 5th and 6th Avenues and cross streets in downtown Anchorage. This project was a standard street resurfacing with a 1.75-inch (44 mm) mill and 2-inch (50 mm) fill. Traffic on 5th and 6th Avenues average from 10,000-15,000 vehicles per day.

To date, performance has been good with minimal damage caused by studded tire wear or traffic loads. In 2019, after four years of traffic, including studded tires, the average rut depths were 0.204 in (5.2 mm) on 5th Avenue and 0.198 in (5 mm) on 6th Avenue. Following the successful project performance, Alaska DOT&PF specified the same PG 64E-40 HiMA binder grade for resurfacing Glenn Highway.

Glenn Highway was paved in 2017, and after two winters, the rut depth was 0.21 in (5.3 mm). Previously, a trial with PG 64-34 and ground tire rubber experienced 0.32 in (8.1 mm) rut depth after two winters, so the HiMA solution reduced rutting by a third. This translates to a 50 percent increase in pavement life before resurfacing is required.

资源

• Full Case Study (PDF)
• Survey and Economic Analysis of Pavement Impacts from Studded Tire Use in Alaska (2019)