EXAM - Tunnel Part - 5

What type of protective canopy must be provided at tunnel portals?

• Timber canopy

• Fire-resistive canopy

• Metal frame canopy

• Temporary canvas canopy

The protective canopy at tunnel portals must project at least:

• 10 feet

• 12 feet

• 15 feet

• 20 feet

Who must design rock bolt support systems in tunnel ground support?

• Site Foreman

• Professional Engineer (PE)

• Construction Supervisor

• Safety Officer

What is strictly prohibited for tunnel ground support?

• Steel ribs

• Timber supports and wood lagging

• Rock bolts

• Chain link fabric

What must be done if tunnel supports are damaged or dislodged?

• Delay work for 24 hours

• Immediately repair or replace them

• Install temporary bracing only

• Remove and leave unsupported temporarily

What must be provided where rock bolts are in use?

• Hydraulic jacks

• Torque meters and torque wrenches

• Bracing beams

• Fire suppression systems

In haulage systems, what must be inspected every shift?

• Signal cables

• Tunnel ventilation

• Locomotives and haulage cars

• Lighting circuits

Man-haul units must be:

• Fully enclosed except for doors and ventilation

• Open at all sides

• Covered with canvas roofs

• Permitted to carry loose construction material

Man-haul units are allowed to carry:

• Construction debris

• Personnel and small secured tools

• Heavy machinery

• Large building materials

Which feature must be provided to prevent accidental dumping in haulage cars?

• Manual clamps

• Positive-locking devices

• Air brakes

• Loose couplers