Which type of excavation is used for laying large pipelines?

Explanation:

Trench Excavation 

• Purpose: Excavation of long, narrow trenches, usually deeper than they are wide.

• Common Use: Specifically for laying large pipelines, sewer lines, water lines, or other underground utilities.

• Support: Often involves shoring or trench boxes to prevent side collapses and ensure worker safety.

• Typical Depths: Can vary from shallow (for cables) to several meters (for large sewer lines).

Additional InformationMuck Excavation

• Purpose: Removal of waterlogged, soft, or unstable materials like mud, silt, and slush.

• Common Use: Often necessary in low-lying or marshy areas where water and soil mix.

• Challenge: The excavated material may not be reusable; it often needs to be transported away.

• Method: May involve dewatering and stabilization techniques before or during excavation.

Rock Excavation

• Purpose: Involves the removal of hard rock surfaces or boulders that cannot be removed with normal digging tools.

• Common Use: Found in hilly, mountainous areas or deep foundation works where bedrock is encountered.

• Method: Requires drilling, blasting, or the use of heavy machinery like breakers or jackhammers.

• Precaution: Safety is crucial due to flying debris and vibrations from blasting.

Open Excavation

• Purpose: Involves excavating a wide and shallow area, typically open to the atmosphere.

• Common Use: Used in foundation works, basements, tanks, roadways, and building sites.

• Advantages: Provides easy access for machinery and workers.

• Limitation: Requires a lot of space and may affect surrounding areas.