2009 - UK - Portable FWD Guide

Deflectometer devices are dynamic non–destructive testing tools commonly used in the field of pavement systems to measure a layer or surface modulus. Among the various testing devices used for non–destructive insitu assessment of pavement layers the Light Weight Deflectometer (LWD) has become the focus of increasing interest. In particular, the changes introduced in the Design Manual for Roads and Bridges (HD 26/06, and IAN 73/09 which superseded HD 25/94), introduced a requirement for field compliance testing of the surface modulus of constructed pavement foundations. In addition, other applications for deflectometers and the portable versions in particular include compliance testing for general highway investigation, (re)construction, highway utility trench reinstatements, and many other similar instances. The portable Light Weight Deflectometers (LWD) are considered in general to be relatively rapid and cost effective tools, if used appropriately.

This report presents a good practice guide for the LWD.