Trench shoring equipment includes trench shields and other shoring devices that are used to prevent a dug trench from caving-in on workers or equipment. In addition to product type, specifications include depth, width, and materials of construction. Depth is given as the depth of the trench or the rail length. Width is specified as the operating range, the width of the trench, or the width of the plate. Materials of construction for trench shoring equipment include aluminum, steel, and stainless steel. Aluminum is a lightweight metal that offers electrical and thermal conductivity, high reflectivity, and good resistance to oxidation. Steel contains less than 1.7% carbon, while stainless steel provides corrosion resistance.
Types of Trench Shoring Equipment
Bedding boxes, crossing bridges, and hydraulic shores are three common types of trench shoring equipment. A bedding box is a fabricated structure that holds bedding material during shipment or temporary onsite containment and storage. A crossing bridge is a temporary structure that is used to move personnel and equipment over open trenches. A hydraulic shore is designed to support the sidewalls of an excavated trench to prevent cave-ins. Such trench shoring equipment consists of hydraulic cylinders (cross braces), vertical rails (uprights), and horizontal rails (walers).
Manhole boxes, shoring plates, and trench boxes or shields are other types of trench shoring equipment. A manhole box provides protection from cave-ins while providing access within for work on a manhole. A shoring plate is a large, rigid plate that is used to hold back dirt. A trench box or trench shield is an assembly that drops into a trench to prevent cave-ins. Some trench boxes and trench shields are adjustable. Others are fixed in width.
Trench shoring equipment includes trench covers, trench slide rails, and trench walers. A trench cover is used to temporarily cover an open trench. A trench rail is a vertical support that is used with shores or jacks to keep plates spread apart. In this way, trench rails are used to maintain trench width. Trench walers serve a similar function, but are horizontal supports rather than vertical supports. Other unlisted, specialized, or proprietary trench shoring equipment is also available.