Medium-sized Drop Weight with 2.0-fold Impact Load
Now you can also test high rigidity without any problems
The new medium-sized drop weight with 2.0-fold impact load “TERRATEST MFG 2.0” was developed by TERRATEST specifically for the use on base courses with high rigidity. The Light Weight Deflectometer with an impact force of 7.07 kN achieves settlements on base courses with a bearing capacity EV2 higher than 120 MN/m2 that are too low to allow for a precise analysis of the test results. It is thus approved for a measuring value up to 70 MN/ m2 Evd or 120 MN/m2 EV2 only. In cases of high rigidity over 120 MN/m2 EV2 no reliable correlation with the static load plate test was possible up to now. With the use of the medium-sized drop weight this is now changing.
Just in time for the BAUMA 2016, TERRATEST® puts the new medium-sized drop weight on the market, which meets all the requirements for the use on base courses with high rigidity. With a double impact load of 14.14 kN, the medium-sized drop weight is especially suitable for testing the bearing capacity of layers without binders according to ZTV SoB-StB, like frost protection layers, rubber and gravel base courses as well as top layers without binders. The medium-sized drop weight can also be used on other layers with comparable bearing capacity, like ground improvements with lime or cement for example. The increased impact force of 14.14 kN is being achieved by using a 15 kg drop weight in connection with stronger disc springs according to DIN 2093-B 63. The maximum normal stress under the load plate thus changes from 0.1 MN/m2 for the Light Weight Deflectometer to 0.2 MN/m2 for the medium-sized drop weight.
The dynamic load plate test with the medium-sized drop weight with 2.0-fold impact load corresponds to the German Technical Test Code for Aggregates in Road Constructions TP Gestein-StB Part 8.2.1. For the calibration of the medium-sized drop weight the calibration instruction TP BF StB Part B 8.4 was released by the German Federal Highway Research Institute (Bundesanstalt für Straßenbau) in March 2016. The medium-sized drop weight with 2.0-fold impact load is approved for a measuring range from 30 MN/m2 to 150 MN/m2. As of now, it adds a precious device version for determining the bearing capacity of layers with a high rigidity to TERRATEST’s product range. In almost no time, the Light Weight Deflectometer can easily be converted into a medium-sized drop weight by quickly exchanging the complete loading device directly on the construction site.