Excavation is one of the most fundamental aspects of modern construction. Not only do our buildings increasingly sturdy reinforcements, but modern inventions, such as telephone wires, domestic pipes and electrical grids, have also necessitated the development of more complex and permanent below-ground placement. The type of excavation required for these projects differs significantly from building-work excavation and therefore requires complementary structural solutions. This is where trench boxes come in.
Types of Trench Box
Put simply, a trench box is a box which sits in a trench. It really is that simple. Of course, this is a very particular type of box – a robust, two sided support system that provides structural support during soil excavation – and a very particular type of trench, wherein the cavity walls must be near-perfectly vertical and completely secure. Trench boxes tend to be made out of either steel or aluminium, which means they’re both incredibly strong and very durable. Unlike piles, they’re capable of supporting two sides of an excavation by means of interchangeable spreaders.
There are many different types of trench box, including:
These different types vary considerably in terms of both size and complexity, so it’s extremely important that excavators choose the right trench box type for their excavation project.
Trench boxes are used primarily in excavation when other solutions, such as piling, wouldn’t be appropriate. Since trenches tend to be long and relatively narrow, trench boxes have been designed with this in mind and are therefore much better suited for supporting unsloped trench runs than any other type of excavation structure. Slope requirements vary by soil type: for example, stable soil can be sloped back to an angle of 53 degrees before requiring additional support, whereas very unstable soil can only be sloped back to 34 degrees before a box is required.
Although sloping is often seen as the least expensive option for trenching, trench boxes do away with much of the associated cost of soil removal. Additionally, boxing a trench provides a huge amount of additional support which is vital for the safety of trench workers. However, proper use is essential for ensuring your boxes are providing optimal protection, so make sure to research your trench specifications and requirements before proceeding with box installation.