01657473

Component

In the United States, the locked wheel skid tester (LWST) fitted with a ribbed tire is the predominant method for testing pavement surfaces (1, 2). Many characteristics of a roadway and the pavement surface influence friction. LWSTs using ribbed tires can detect microtexture issues easier. However, macrotexture and travel speed are both critical factors that affect available surface friction, factors that cannot be measured with a ribbed tire friction test. Although the LWST is the common device used to measure friction in the United States, globally, there are many methods and equipment used to test friction. All devices used for testing friction will have different sensitivities to these macrotexture and travel speed. The differences in sensitivity arise from different design and configuration features regarding the tire, the body, and the applied testing methodology. Since these different sensitivities to road characteristics result in different values of friction measured with different devices at identical travel speed, there have been many past efforts to compare the different devices. The purpose of this paper is to compare measurements from three different devices using orthogonal regression with equal variances: an LWST equipped with both a ribbed and smooth tire, a Grip Tester, and a Sideway Force Coefficient Routine Investigation Machine (SCRIM). After comparison, the Grip Tester and SCRIM are highly correlated when the International Friction Index (IFI) is used to correct for slip speed. Lastly, the SCRIM is highly correlated with the LWST ribbed tire, whereas the Grip Tester is highly correlated with the LWST smooth tire.

This paper was sponsored by TRB committee AFD90 Standing Committee on Pavement Surface Properties and Vehicle Interaction. Alternate title: A Comparison of Locked Wheel and Continuous Friction Measurement Equipment

18-01277

English

11p

2018

Transportation Research Board 97th Annual Meeting

Digital/other

Figures; Photos; References

Field tests; Friction tests; Pavement performance; Pavements; Regression analysis; Rolling contact; Skid resistance tests; Surface friction (Geophysics); Tires

International Friction Index; Sideway-Force Coefficient Routine Investigation Machine

Continuous friction measuring equipment; Locked wheel testers; Road grip testing

Highways; Pavements; Vehicles and Equipment

Transportation Research Board Annual Meeting 2018 Paper #18-01277

TRIS, TRB, ATRI

Jan 8 2018 10:19AM