ASTM D4553-18

5.1 Results of this test method are used to predict time-dependent deformation characteristics of a rock mass resulting from loading. It is a test that may be required depending on rock type or anticipated loads, or both.

5.2 This test method may be useful in structural design analysis where loading is applied over an extensive period.

5.3 This test method is normally performed at ambient temperature in the field, but equipment can be modified or substituted for operations at other temperatures.

5.4 Results of this test method may be useful in verifying laboratory creep data and structural mathematical modeling analyses.

5.5 Creep characteristics are determined under a nonuniform state of stress within the rock mass underneath the plate.

5.6 If during a field investigation, time-dependent characteristics are detected, then an in situ creep test shall be performed.

1.1 This test method covers the preparation, equipment, test procedure, and data documentation for determining in situ creep characteristics of a rock mass using a rigid plate loading method.

1.2 This test method is designed to be conducted in an adit or small underground chamber; however, with suitable modifications, this test could be conducted at the surface.

1.3 The test is usually conducted parallel or perpendicular to the anticipated axis of thrust, as dictated by the design load or other orientations, based upon the application.

1.4 Flexible plate apparatus can be used if the anticipated creep displacement is within the tolerance of the travel of the flat jacks.

1.5 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. Reporting of test results in units other than inch-pound shall not be regarded as nonconformance with this standard.

1.6 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026, unless superseded by this test method.

1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.