33 - Tunnel Engineering

What is one of the major factors considered by civil engineers when designing tunnels?

• The color of the soil

• The mechanical properties of the soil

• The height of nearby buildings

• The temperature of the air

Why is wet, clay-rich soil considered challenging in tunnel engineering?

• It is too hard to dig through

• It acts more like a lubricant than a structural material

• It is too dry and brittle

• It is too expensive to work with

Which method of tunnel construction involves digging a trench and then backfilling it after the tunnel lining is built?

• Top-down method

• Bottom-up method

• Immersed-tube method

• Bored tunnel method

Which method of tunneling is often the only feasible alternative in congested urban areas?

• Top-down method

• Bottom-up method

• Immersed-tube method

• Directional control method

What is a significant disadvantage of immersed-tube tunnels?

• They are less vulnerable to waterborne traffic

• They have a lower environmental impact

• They are more likely to be damaged by anchor strikes

• They are longer than bored tunnels