The Technical File | Groundforce Groundforce Shorco | Technical File Issue 3.0 Trench Boxes Features and benefits Simple installation methodology. Extension boxes can be quickly added to achieve deeper trenches; up to a maximum to two top boxes. Various sizes available to cater for a wide variety of applications. Trench boxes may be installed in either a pre-dug trench in stable ground, or by a progressive `dig & push’ method. Enables rapid construction of pipe work chambers and interceptors. Strut Types Multibox incremental telescopic system (mini & standard box). Heavy duty incremental telescopic system (premier box). Adjustable spindle system (all trench boxes except Premier). Trench boxes are generally the first choice for the rapid shoring of trench runs in non-urban environments due to the speed and simplicity of installation. In reasonable ground conditions, they are generally suitable for use in trenches up to 4m wide x 6.6m deep, depending on box type, and used where prevention of ground movement is not a key issue. They are often installed longitudinally in multiple units to continuously support a length of trench. A minimum of three boxes installed end to end should be used at any one time. Groundforce offer a wide range of trench box sizes with two basic strut types. The “Multi-Box” type of strut is a heavy duty, incrementally adjustable, telescopic strut whereas the “spindle” type uses the more traditional screw thread method of adjustment. Multi boxes struts are more suited to wider trench widths. A maximum of two top extension boxes can be added to increase the height of a base box. Trench widths of between 520mm and 4650mm (inside of box) can be achieved with various combinations of adjustable spindle and extensions. It is recommended that all trench boxes are used with integral Edgesafe and Laddersafe barrier and access systems. Product Link Box Struts - Section 9.5 Box Ancillaries - Section 9.7 9.2.1