Shoring devices (also called trench shoring, shoring boxes, or sliding rail shoring) are steel frame systems deployed in open trenches to secure trench walls against collapse and protect workers from cave-in hazards. From 1.25 m trench depth onwards, shoring is mandatory under DGUV Rule 101-004 in most soil types.
Standard types include: light shoring boxes (aluminum/steel, for trenches up to 3 m deep), heavy shoring plates (steel, up to 6 m), sliding rail shoring (infinitely depth-adjustable, up to 7 m), and chamber plate shoring (for wide excavation pits). Boxes are positioned in the trench by excavator and pulled in with excavated material — the trench is opened section by section.
Leading manufacturers include Krings (SBH series), Emunds+Staudinger, SBH Tiefbautechnik, and Ischebeck. Modern shoring devices feature hydraulic spreaders that actively accommodate earth pressure and automatically adapt to trench width. The correct choice of shoring system depends on trench depth, soil type, groundwater level, and available excavator capacity.