Working underground? There’s zero margin for error. Trench collapses don’t give warnings; they hit fast and hit hard. Shoring is how you keep everyone and everything safe. It stabilizes the ground and prevents cave-ins.
In this guide, we’ll walk through what shoring is, when you need it, how to install and remove the shoring systems safely, and a few other important points you need to know.
What is shoring?
It is a process of providing temporary structural support to trenches in construction and excavation projects. It offers lateral support and prevents the trench walls from collapsing.
Consider loose soil that can slide or cave in, it poses a risk of injuries and burial for the labourers working in the trench. Safe Work Australia requires a trench to be secured through safe work methods if it’s more than 1.5 meters deep. They label it as high-risk construction work that requires protective measures.
Types of shoring
Hydraulic shoring systems
Hydraulic shoring consists of a metal structure with 2 metal plates laterally connected with each other through metal beams called walers.
It is put in the trench and pushed outwards through hydraulic pressure until it’s fully braced in the trench. It’s a reusable and mobile system. You can move it around the trench and store it once you’re done.
Steel sheet piling
This shoring method involves large steel sheets that are placed inside the trench. They have an interlocking system allowing them to connect with each other to form a continuous wall around the trench.
Engineers use it for major excavations, especially near existing buildings. They especially use it in unstable ground conditions, like loose or running sand, where the risk of collapse during excavation is high.
Timber soldier set
Timber shoring involves a similar structure to hydraulic shoring, but is made with timber. It is suitable for rock, stiff clays, and self-supporting soils. It doesn’t offer continuous protection, as the timber shoring is placed at regular intervals.
Shoring vs shielding
Before diving deep , it’s important to understand how they both differ.
Most people often confuse shoring and shielding interchangeably. Though they use similar equipment and processes, their functionality is different. The former is a preventive measure against collapse, while shielding is a protective measure in case the soil crumbles down.
In shoring, the metal plates of the box or system are in contact with the trench walls, exerting an outward pressure and preventing soil collapse.
While in shielding, the trench box isn’t compacted in the trench; rather, it’s free and has significant space between the metal plates and trench walls. In case a collapse happens, the shielding stops all the rocks and debris, protecting the workers within the trench.
Trench boxes
Trench boxes or shoring boxes are highly popular for shielding. Contractors place them inside the trench through an excavator and move them along the trench as the work progresses.
They come in two different materials, aluminium and steel. The aluminium boxes are lightweight and durable, while the steel trench boxes are heavy yet a popular choice among contractors.
How to install a shoring system
The installation differs for different types. This process should be carried out with caution and under the supervision of a trained person.
At Legend Hire, we offer engineering support and installation services to our customers so they can have safely installed systems that offer maximum protection to everyone on site.
Though there is no one installation process, a few steps are common no matter the type.
1. Analyze the trench conditions
Conduct a thorough site analysis. Evaluate soil type, water content, trench depth, risk factors, and nearby structures. This assessment is done by a trained person and determines what kind of system is safe to install.
2. Inspect and assemble the shoring
Inspect the system or its parts for any damage. Using damaged or weak shoring risks the lives of the workers. Your shoring should be in perfect shape for installation. If you’re not using a pre-fabricated system, assemble the parts after inspection.
3. Install the shoring system
Carefully lower the shoring equipment into the trench. The installation process differs for different shoring types. Make sure hydraulic shores are properly pressurized and trench boxes are aligned correctly. If you’re using timber shoring, brace and secure all boards tightly.
4. Check alignment and stability
Once installed, double-check that the system is firm against trench walls and free of movement. Uneven or poorly installed shoring can lead to dangerous accidents.
When and how to remove shoring
The shoring will be in place as long as the trench work is in process. Once the trench work is done, you can start removing the shoring system.
The exact process and equipment required will depend on the shoring type you have used. However, here are some tips that you must consider, no matter the shoring type.
- Work backwards: Take out the shoring in the exact opposite order from installation.
- Stay protected: Workers in the trench must always stay within the protected area.
- Pay attention to falling parts: Ensure that structural members don’t fall and hit anyone during removal.
- Add temporary supports if needed: You might need to put in temporary structural supports before you start removing the main shoring system. This gives extra protection during the removal process.
8 essential trench safety tips you can’t miss
There are multiple factors to consider for trench safety. These safety considerations start before digging and end with the backfilling of the trench. Here are the most important safety measures you need to take to create a safe work environment for your workers.
- Map out the location of sewer, electric, telephone, fuel, and water lines. Knowing exactly where these lines are helps you plan your trench path more safely and avoid expensive damage.
- Assess the traffic conditions around the excavation site as they create additional hazards and distractions. You can also add barriers or signage to protect workers from being struck.
- Assign a competent person to inspect the trench daily. Though you must train this person to identify hazards such as wall movement, cracks, or soil buildup.
- Gases like methane or carbon monoxide can accumulate in confined spaces. Use gas detectors to ensure oxygen levels are safe before entry.
- Maintain and inspect shoring, trench boxes, and sloping daily. In case of any damage, replace the material with a sound one.
- Keep all the equipment and soil piles at least 2 feet from trench edges. This prevents added pressure on trench walls and reduces the risk of materials falling in. It also provides more room for safe entry and exit.
- Never stand or work under suspended loads. This includes buckets, pipes, or beams lifted by cranes or excavators.
- Provide safe entry and exit for any trench over 1.2 meters deep. This includes ladders, ramps, or steps that are sturdy and properly placed.
Check out Legend Hire’s trench safety equipment.
Expert advice and shoring solutions for everyone
No matter how small or complex your location and requirements are, our team of engineers is available to guide you to the right system and trench safety gear. We also provide trench boxes and shoring solutions for hire with installation by trained workers and engineers.