ASTM E1960-07(2015)
Standard Practice for Calculating International Friction Index of a Pavement Surface

Standard No.

ASTM E1960-07(2015)

Release Date

2007

Published By

American Society for Testing and Materials (ASTM)

Status

Be replaced

Replace By

ASTM E1960-07(2023)

Latest

ASTM E1960-07(2023)

Scope

5.1 This is the practice for calculating the IFI of the pavement. The IFI has proven useful for harmonization of the friction measuring equipment. F60 and S_p have proven to be able to predict the speed dependence of wet pavement–related measurements of the various types of friction-measuring equipment.2 The two IFI parameters (F60 and S_p ) have been found to be reliable predictors of the dependence of wet pavement friction on tire slip and vehicle speed.

5.2 The IFI parameters, F60 and S_p, can be used to calculate the calibrated friction at another–slip speed using a transformation equation.

5.3 The IFI model given below describes the relationship between the values of wet pavement friction FRS measured at a slip speed of S and between the friction values measured by different types of equipment.

5.4 A significance of the IFI Model is that the measurement of friction with a device does not have to be at one of the speeds run in the experiment. FRS can be measured at some S and is always adjusted to FR60. Thus, if a device can not maintain its normal operating speed and must run at some speed higher or lower because of traffic, the model still works well. In that case S is determined by the vehicle speed (V) which can be converted to S by multiplying V by the percent slip for fixed slip equipment or by multiplying V by the sine of the slip angle for side force equipment.

5.5 This practice does not address the problems associated with obtaining a measured friction or measured macrotexture.

1.1 This practice covers the calculation of the International Friction Index (IFI) from a measurement of pavement macrotexture and wet pavement friction. The IFI was developed in the PIARC International Experiment to Compare and Harmonize Texture and Skid Resistance Measurements. The index allows for the harmonizing of friction measurements with different equipment to a common calibrated index. This practice provides for harmonization of friction reporting for devices that use a smooth tread test tire.

1.2 The IFI consists of two parameters that report the calibrated wet friction at 60 km/h (F60) and the speed constant of wet pavement friction (S_p).

1.3x00a0......

ASTM E1960-07(2015) Referenced Document

• ASTM E1845 Standard Practice for Calculating Pavement Macrotexture Mean Profile Depth
• ASTM E1911 Standard Test Method for Measuring Paved Surface Frictional Properties Using the Dynamic Friction Tester
• ASTM E867 Terminology Relating to Vehicle-Pavement Systems

ASTM E1960-07(2015) history

• 2023 ASTM E1960-07(2023) Standard Practice for Calculating International Friction Index of a Pavement Surface
• 2007 ASTM E1960-07(2015) Standard Practice for Calculating International Friction Index of a Pavement Surface
• 2007 ASTM E1960-07(2011) Standard Practice for Calculating International Friction Index of a Pavement Surface
• 2007 ASTM E1960-07 Standard Practice for Calculating International Friction Index of a Pavement Surface
• 2003 ASTM E1960-03e1 Standard Practice for Calculating International Friction Index of a Pavement Surface
• 2003 ASTM E1960-03 Standard Practice for Calculating International Friction Index of a Pavement Surface
• 1998 ASTM E1960-98 Standard Practice for Calculating International Friction Index of a Pavement Surface