ASTM A981/A981M - Standard Test Method for Evaluating Bond Strength for Steel Prestressing Strand

ASTM A981 / ASTM A981M is a test method that establishes the relative bond strength of 0.600-in. [15.24-mm] Diameter Steel Prestressing Strand, Grade 270 [1860], Uncoated, Used in Prestressed Ground Anchors prestressing cement grout. This method is primarily used for evaluating the impact of manufacturing practices on bond strength in prestressed ground anchors. It should be noted that the bond strength values obtained from this test should not be used to design the bond strength of ground anchors under field conditions.

This test method is not intended for assessing the bond strength in pretensioned concrete applications. The test specimen is obtained by cutting from standard production coils and should not be wiped or cleaned before testing. The pull test is conducted in accordance with the specified method.

The scope of ASTM A981 / ASTM A981M focuses on establishing the relative bond strength of 0.600-inch (15.24 mm) diameter, Grade 270 (1860) steel prestressing strand in cement grout for prestressed ground anchors. The purpose is to evaluate how manufacturing practices affect bond strength.

It is important to note that the bond strength values obtained through this test method should not be used to determine the bond length of ground anchors in actual field conditions. Additionally, this test method is not suitable for bond testing in prestressed concrete applications.

The standard provides values in both inch-pound and SI units, with the SI units indicated in brackets. Although the values in each system may not be exact equivalents, both systems are considered standard. It is recommended to use each system independently, as combining values from the two systems may result in non-conformance with the standard.