The VB 100 Manhole Box is always used when the job leads to a manhole structure; the working trench needs to become wider before you can continue with the pipe installation. These special trench boxes provide complete protection for the workers.
The trench shoring plate body is designed as an U-form and the wings have a widths of 0.50 m. Thus, a 1.0 m wide manhole is formed, preventing stones and soil from slipping into the excavation (working area). The manhole box allows for a wider trench support at the working area, without having to widen the entire trench.
The maximum plate length is 4.0 m, the pipe clearance is 1.54 m, keeping it similar to the VB 100 trench boxes. The VB 100 Manhole Boxes can be installed to a depths of up to ~5.0 m using one base and two top boxes. The height of the base box is 2.56 m and the top boxes are 1.41 m high.
All struts and strut extensions are the same than being used in our systems VB 60 and VB 100, i.e. they are interchangeable. The system can be used for a trench width of 2.20 m to 5.0 m.
The struts are bolted to articulated spring mushroom fittings, which are connected to the plates. Due to the rugged standard strut, the system can also be installed in poor or unstable soil conditions. The Shoring Box is pushed vertically into the ground by alternately pushing and lowering (Dig and Push method).
