A TBM machine jam can turn a week into a month

You can see that a TBM machine jam can turn a week into a month. Imagine a traffic jam in a tunnel with only one lane; everything halts until the blockage is cleared. CEGC provides tunnel machine solutions for all types of projects, including TBM, auger boring machines, and Microtunnelling Machines.

Key Takeaways

• TBM jams can happen because of hard ground, broken parts, or bad planning. Knowing why jams happen helps stop delays.

• Fixing a TBM jam is hard and can make the project take much longer. Get ready for surprises to keep the project moving.

• Picking the right tunneling machine, like auger boring or Microtunnelling Machines, can help avoid jams and save time.

A TBM machine jam can turn a week into a month—Why?

What Causes a TBM Jam?

You might ask why a TBM jam happens. Many things can stop a tunnel boring machine. The main reasons are tough ground, broken parts, and problems with planning.

• Squeezing rock pushes on the TBM and makes it hard to move.

• If the ground falls in, it blocks the TBM’s way.

• Moving earth can fill up the tunnel and trap the TBM.

• Fault zones and fracture zones make the ground weak.

• Water coming in can flood the tunnel and stop the TBM.

Broken parts also cause jams. Cutterheads can break or get stuck. Motors and hydraulic systems can stop working if they get too much stress. If spare parts or tools are late, it makes things worse.

The tunnel itself can be risky. Small tunnels make it hard to fix the TBM. If the ground lets water or gas in, it can surprise workers. The TBM must be built for the ground. If not, it can jam.

Jams happen more in bad rock. When the TBM gets close to these spots, you might see big changes in torque and thrust. These are signs that a jam could happen soon.

Tip: You can lower the chance of jams by not digging too much, keeping face pressure, and using grouting. Always follow the rules if a jam happens.

CEGC gives TBM tunnel boring machines and other tools for all kinds of ground. You can pick the right machine for squeezing rock, moving earth, or mixed ground.

How TBM Jams Multiply Delays

A TBM machine jam can turn a week into a month because fixing it is very hard. Most TBMs have a closed shield, so you cannot reach the jam easily. You cannot just walk to the problem and fix it. Sometimes you must dig a new shaft or even dig by hand, which takes a long time.

Strange ground makes delays worse. You may not know what caused the jam until you check. Sometimes you must wait for experts to look at the problem and find the safest way to fix it. This makes it hard to plan your work.

Here is a simple table that shows how surprises can change your project:

When a TBM jams, you might need to change worker plans, order new parts, or even change the tunnel design. Each step takes more time. Safety risks go up. Workers face dangers from weak ground and small spaces. You must check for risks to keep everyone safe.

A TBM machine jam can turn a week into a month because every hour spent fixing it means lost work. In cities, TBM jams can shake the ground and bother people nearby. People may feel dizzy or tired from the noise and shaking.

You can learn from old projects. When geostress lets go, it makes the TBM harder to move and can cause jams. Big projects with unknown ground are even riskier. You must always be ready for surprises.

Remember, CEGC has many tunnel machine solutions, like TBM, auger boring machine, and Microtunnelling Machine. You can find the best machine for any ground and lower the chance that a TBM machine jam can turn a week into a month.

Project Impacts of TBM Jams

Timeline Extensions and Cost Overruns

When a tunnel boring machine jams, work does not just stop for a little while. A TBM machine jam can make a week-long job last a whole month. One problem can lead to more problems and cost more money. If one cutter gets blocked, other cutters can get stuck too. This can stop the whole machine from working. If you do not fix the jam fast, the cutterhead can break. This means you lose even more time.

You also have to think about extra costs. Many contractors add more money to their bids because of these risks. Insurance for tunneling projects costs a lot more than for other jobs. Here are some reasons why costs go up:

• Tunnel collapse risk means long delays and more money spent.

• Contractors charge more to cover ground problems.

• Insurance for tunneling is 2-4% of the total cost, but other jobs pay only 0.5-1%.

Effects on Scheduling and Resources

A TBM jam does not just slow down the timeline. You also have to change how you use your team and machines. When the machine stops, you might move workers to other jobs. Sometimes you need to call in experts to help. Studies show you often have to move people and tools around when a jam happens to save time.

You can look at other tunneling methods. Auger boring machines and Microtunnelling Machines are easier to fix and take less time to repair. CEGC has many tunnel machine choices. You can pick the best one for your project and lower the chance that a TBM machine jam can turn a week into a month.

You get big delays and spend more money when a TBM jams. Hard ground and tricky rocks make fixing jams hard to guess. The table below shows what can happen for a long time:

You can lower risks if you ask CEGC for help with live checks and better plans.

FAQ

What is a TBM tunnel boring machine?

A TBM tunnel boring machine digs tunnels underground. You use it for big projects like subways, water pipes, or utility tunnels.

How does a TBM jam affect your project?

You face long delays and higher costs. You may need to stop work, move teams, or bring in experts to fix the problem.

How do auger boring machines and Microtunnelling Machines compare to TBMs?

You use auger boring machines for short, simple crossings. Microtunnelling Machines work well for precise, longer drives. TBMs handle large tunnels in tough ground.