Stehr - Plate Compactores on Road Roller
Compaction is a major cost factor in any construction job. Problems can arise when using conventional compaction devices (rollers, cylinders, etc.) especially when laying loose or unfixed materials. What happens is that these drum rollers cause the material being compacted to shift upwards toward the surface, which means several runs have to be made to complete the job. In cases like this you usually have to make more than one run with another vehicle (Unimog or the like) equipped with mechanical plate compactors in order to achieve the desired results. Stehr has developed a vibrating plate compactor for attachment to road rollers. Thanks to its combined roller and plate configuration, it puts several complex steps together into one machine and does them all in one single run.
Stehr plate compactors achieved absolutely amazing results when employed at the construction sites of several well-known companies. Tests made by earthworks laboratories have proven its excellence. EV2 values of over 100 MN/m2 were often attained in only one run!!!
How it works:
Loose material being compacted by a cylindrical roller is subject to a so-called bow wave effect, which is caused by already compacted material shifting toward the surface. Compaction results in depth are good, however, the material to be compacted in the upper layer becomes loosened once again. Now come the Stehr plate compactors directly behind the roller to deliver outstanding results on the upper layer.
Stehr plate compactors work using two counteraction eccentric shafts enabling a completely vertical compaction line. This means that the force is applied 100% vertically into the ground. Stehr's road roller combination with attached plate compactors unifies the excellent compaction performance of the roller in depth with the outstanding effectiveness of plate compaction in the upper layer. The roller operates at low frequency and high amplitude (30 Hz), while the plate compactors work at high frequency (60 Hz) and low amplitude. This ideal convergence of compaction forces of different direction and frequencies ensures a marked improvement in compaction results compared to performing these as individual work steps.
Plate compactors can be attached and removed quickly and easily using a specially developed combination quick-change lever system.
1. Attaching the plate compactor
2. Elevating the plate compactor
3. Plate compactor in operating position
