Megha Engineering & Infrastructures Tunnel Engineer Interview Questions, Process, and Tips

NATM stands for New Austrian Tunneling Method, a construction method for tunnels.

• NATM is a tunneling method that involves excavating the tunnel while providing support using rock bolts, shotcrete, and steel ribs.

• It is a flexible and adaptable method that allows for adjustments during construction based on the geological conditions encountered.

• NATM is commonly used in soft ground conditions where traditional tunneling m...read more

Standup time refers to the time it takes for concrete to set and gain enough strength to support itself. Tunnel supports are structures used to stabilize the tunnel walls and roof.

• Standup time is crucial for ensuring the stability of the tunnel during construction.

• Tunnel supports can include rock bolts, shotcrete, steel ribs, and lattice girders.

• The type of tunnel support used depends on the geology of the surrounding ...read more

Blast details include powder factor and quantity of explosives used.

• Powder factor is the amount of explosives used per unit volume of rock to be blasted

• Quantity of explosives used is typically measured in kilograms or pounds

• Blast details are crucial for ensuring safe and efficient tunnel excavation

Cycle time is the total time taken to complete a task or process from start to finish.

• Cycle time includes all the time spent on actual work as well as any waiting time or delays.

• It is an important metric in project management to assess efficiency and productivity.

• For tunnel engineering, cycle time could refer to the time taken to complete a specific phase of tunnel construction, such as excavation or lining installatio

Powder factor is a measure of the amount of explosive used per unit volume of rock in tunneling operations.

• Powder factor is calculated by dividing the weight of explosives used by the volume of rock being blasted.

• It is typically expressed in units of kilograms or pounds of explosives per cubic meter or cubic yard of rock.

• A higher powder factor indicates a greater amount of explosives used, which can result in more effi...read more

RMR value stands for Rock Mass Rating value, which is a geotechnical classification system used to assess the quality of rock masses.

• RMR value is used in tunnel engineering to evaluate the stability and support requirements of rock masses.

• It takes into account various parameters such as rock strength, joint conditions, groundwater conditions, and orientation of discontinuities.

• RMR values range from 0 to 100, with highe...read more

Pullout test is a method to determine the bond strength between concrete and reinforcement in a structure.

• Pullout test involves applying a tensile force to a steel bar embedded in concrete to measure the force required to pull it out.

• It is used to assess the quality of concrete and the effectiveness of reinforcement in a structure.

• The test helps in evaluating the bond strength between concrete and reinforcement, which ...read more

Cycle time of advancement refers to the time taken for the tunnel boring machine to progress a certain distance.

• Cycle time can vary depending on factors such as geology, machine efficiency, and crew experience.

• For example, a tunnel boring machine may advance 10-15 meters per day in stable rock conditions.

• However, in more challenging ground conditions, the cycle time may be slower due to the need for additional support ...read more