Trench box
A trench is an excavation, the length of which greatly exceeds its depth. Shallow trenches are usually considered to be less than 6 m deep and deep trenches greater than 6 m. Trenches are commonly required to allow services, pipelines or foundations to be laid.
Over short periods of time, for relatively shallow depths most soil types will stand almost vertically without difficulty. However, trenches other than those which are relatively shallow may require support.
A trench box is a temporary retaining structure which allows the sides of the trench to be cut vertically or near-vertically. Trench boxes are suitable for low-risk situations in stable, dry ground, often when other solutions, e.g. piling, would be inappropriate.
Trench boxes are typically made from steel or aluminium and are two-sided, supporting both sides of an excavation, separated by spreaders. They require at least two separating struts per panel for stability.
Trench boxes can be placed in pre-excavated trenches or installed using a ‘dig and push’ technique. This involves pushing them into the ground as the excavation proceeds with an excavator removing soil from between the panels, while ensuring that the sides of the trench are supported at all times. The trench width must be sufficient to accommodate what is being laid in the trench, the width of the excavator bucket, and the thickness of the box panels.
[edit] Related articles on Designing Buildings Wiki
Featured articles and news
Getting the most out of heat pumps and heating
How heat pumps work and how they work best.
Plumbing and heating for successful retrofit and renovation
Low temperature underfloor systems and heat pumps.
Cost-of-living crisis and home improvement plans
Starting on the right footing and top tips for projects.
Delays on construction projects
Types, mitigation and the acceleration of works.
From Chaucer to Fawlty Towers.
Electrotechnical excellence, now open for entries.
Net zero electricity grids BSRIA guide NZG 5/2024
Outlining the changes needed to transition to net zero.
CIOB Global Student Challenge 2024
Universitas Indonesia wins for second year running.
New project and cultural district described in detail.
The nature of EPCs, crticism and inaccuracies.
History, issues and redesign.
From waste recycling to energy performance the hierchy.
An introduction to WERCS and WEEE responsibilities
Dealing with 2 million tonnes of waste equipment a year.
Global BACS Market: analytics and optimisation
A BSRIA glance at building automation and control systems.
What it is and how to use it.
Types of insulating plaster by binder and insulant.
Investors in People: CIOB achieves gold
Reflecting a commitment to employees and members.
Scratching beneath the surface; a guide to selection.
ECA 2024 Apprentice of the Year Award
Entries open for submission until May 31.
UK gov apprenticeship funding from April 2024
Brief summary the policy paper updated in March.