The Technical File | Groundforce Groundforce Shorco | Technical File Issue 3.0 Manhole Boxes Features and benefits Simple installation methodology. Extension boxes can be quickly added and connected by a simple pinned arrangement to achieve deeper trenches; up to a maximum to two top boxes can be added. A large range is available to cater for a wide variety of manhole rings. Manhole boxes may be installed in either a pre-dug trench in stable ground, or by a progressive `dig & push` method. A full range of integrated handrail systems are available along with end closure panels. End closure panels are available to support the open ends of the manhole box (see Box Ancillaries 9.7.2). Compatible Strut Types Multibox telescopic incrementally adjustable system (2.5m to 4.0m Boxes). Adjustable Spindle system (2.5m to 4.0m Boxes). Fixed Length Extension (4.7m Box only). Manhole boxes are similar to trench boxes in their basic function, however they incorporate integral end return panels to provide additional ground support across the end of a trench making them ideal for installing precast manhole rings within trench runs. There are five basic sizes of Manhole Box available within the Groundforce fleet to cater for all common sizes of precast manhole rings. Each box can be assembled and installed quickly using appropriate machinery and without the need for an operative to enter the unsupported excavation. Manhole Boxes can be used in most ground conditions to support trenches of up depths of up to 5.5m by utilising the base module with two interconnected box top units. Trench widths of between 1.6m and 5.4m can be achieved with various combinations of strut and panel type. Note that manhole boxes are heavy and therefore great consideration should always be made to the weight of the box and the capability of the lifting equipment employed to lift and handle it. It is recommended that all manhole boxes are used with integral Edgesafe and Laddersafe barrier and access systems. Product Link Box Struts - Section 9.5 Box Ancillaries - Section 9.7 9.3.1