Light Weight Deflectometer’s (LWD’s) are a light weight, portable tool used to determine the stiffness of unbound materials (subgrade/subsoils and base layers, granular layers & backfilling materials) or sometimes partially bound material (e.g. stabilised) during construction or pavement rehabilitation.
The LWD is used for allowable bearing capacity Quality Assurance (QA) of prepared surfaces, prior to the installation of permanent structures (e.g. slabs, footings, pavements) or temporary works platforms (crane pads, piling rigs). The bearing capacity under the plate is from 30 – 400 kPa, achieved by changing plate diameters, drop weights and drop height.
Applications include flexible pavements, unsealed roads and mine access roads, tunnels, railway track beds, airport runway and taxiways, hard standing areas, dam construction, canal building, embankments, temporary works platforms (crane pads and piling rigs), building foundations (footings and slabs), wind farms, pipe laying, contaminated sites and tank farms.
The QUT Falling Weight Deflectometer (FWD) apparatus is designed to accommodate plates with diameters of 300 mm and 150 mm, along with falling weights of 10 kg and 15 kg.
