8000 FALLING WEIGHT DEFLECTOMETER (FWD)
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8000 FALLING WEIGHT DEFLECTOMETER (FWD) Dynatest is the original commercial developer of the Falling Weight Deflectometer (FWD) technology and is the world’s largest supplier of FWD deflection based equipment. The FWD is designed to impart a load pulse to the pavement surface simulating the load produced by a rolling vehicle wheel. The load is produced by dropping a large weight onto a set of rubber buffers on a bracket connected to a circular load plate. A load cell mounted on top of the plate measures the imparted load. Deflection sensors (geophones) mounted in and radially from the center of the load plate measure the deformation of the pavement in response to the load. The post processing software, Dynatest ELMOD (Evaluation of layer Moduli and Overlay Design) can be used to back-calculate the pavement layer moduli based on the impact load and surface deflection basin. The results can effectively be used for the evaluation of pavement structural condition and overlay design based on empirical or mechanistic- empirical pavement design guides. The FWD data can also be used to calculate the degree of load transfer between adjacent concrete slabs, and to detect voids under slabs in rigid pavements.

■ KEY FEATURES Nondestructive structural testing device Fast calculation of the seasonally adjusted moduli, residual life of the pavement, and required overlay thickness for a given service life ■ AVAILABLE UPGRADE OPTIONS Folding trailer for ease of shipment Global Positioning System (GPS) Ideal for comprehensive testing for mechanistic-empirical analysis and design Wide loading range—900–27,000 lbf (4–120 kN); suitable for testing a variety of paved and unpaved roadways, parking lots and airfield surfaces Excellent repeatability and stability For maintenance and rehabilitation (M&R), the...