ASTM D4695−03 Reapproved 2015 Standard Guide for General Pavement Deflection Measurements

ASTM D4695−03 Reapproved 2015 Standard Guide for General Pavement Deflection Measurements

Scope
1.1 This guide provides procedural information for measuring pavement surface deflections, directly under, or at locations radially outward (offset) from a known static, steady-state, or impulse load.

Deflections are measured with sensors that monitor the vertical movement of a pavement surface due to the load.

This guide describes procedures for the deflection measurement using various deflection testing devices and provides the general information that should be obtained regardless of the type of testing device used.

1.2 This guide is applicable for deflection measurements performed on flexible asphalt concrete (AC), rigid portland cement concrete (PCC), or composite (AC/PCC) pavements.

Rigid pavements may be plain, jointed, jointed reinforced, or continuously reinforced concrete.

1.3 The values stated in SI units are to be regarded as standard. Inch-pound units given in parentheses are for information purposes only.

ASTM D4695−03 Reapproved 2015 Standard Guide for General Pavement Deflection Measurements

Significance and Use

5.1 NDT measurement of pavement surface deflections provides information that can be used for the structural evaluation of new or in-service pavements.

These deflection measurements may be used to determine the following pavement characteristics:

5.1.1 Modulus of each layer.

5.1.2 Overall stiffness of the pavement system.

5.1.3 Load transfer efficiency of PCC pavement joints.

5.1.4 Modulus of subgrade reaction.