| 摘要 |
<p>When manholes and trenches are excavated in traffic areas by traditional methods, the back-fill material oftens sinks and the edges re-emerge only a short time after the manholes or trenches have been closed. To avoid such damage, it is suggested to make the lateral edges of the manholes (10, 11, 12) or trenches stepped. A device for achieving this has a trailer (1) which can be steered and driven and is allowed to use the road network, and onto which is mounted a hydraulic unit which can drive a circular saw blade that can be mounted on the trailer (1), as well as a hydraulic hammer. This device makes the process easy to implement, resulting in manholes (10, 11, 12) and trenches which, besides not sinking, also have precise measurements and clean joints.</p> |
