Light Weight Deflectometer, LWD

LWD measurements are carried out, similar to the static plate load test, to determine the deformation properties of the soil. The LWD measurement is quick to perform and the equipment can be easily and quickly moved around the site. During the measurement, it is easy to adjust the drop height and/or the plate diameter so that the measurements are carried out at exactly the loads that the individual layers are exposed to in the finished construction.

LWD measurements are often used in combination with static plate load tests, where a large number of LWD measurements are carried out as a screening of a building site. The many measurements can then be calibrated against individual plate load tests placed strategically in the construction site.

The LWD bob is also often used as an alternative to compaction control with an isotope probe, where the firmness of the filling material is determined over larger areas.

The measurement is carried out according to the German standard, TP BF-StB Part B 8.3