ASTM D4694-09 (R2020) PDF Download

ASTM D4694-09 (R2020) is a standard test method that determines the deflections of pavement surfaces using a falling-weight-type impulse load device, also known as a falling-weight deflectometer (FWD). The test method focuses on measuring the vertical deflection response of the pavement surface when an impulse load is applied. The deflections are measured at the center of the applied load and at various distances away from the load axis.

The main purpose of conducting these deflection measurements is to assess the performance of the pavement and obtain information about the in-situ material characteristics of the pavement layers. The data obtained from this test method can be used for structural evaluation of load carrying capacity, as well as determining overlay thickness requirements for highway and airfield pavements. By measuring and analyzing the deflections, the test method provides valuable insights into the condition and strength of the pavement.