What does open trench mean?

What does open trench mean?

Open trench excavation consists of digging down to and exposing the existing pipe, removing the existing pipe or a section of it, installing a new pipe or a section of new pipe, and then backfilling the trench. Cover open trenches with steel plates at the end of each day as needed while work is in progress.

What is open trench pipe laying?

Open-trench pipe-laying To start with, a trench is excavated along the planned pipeline route. If the in-situ soil does not offer a suitable pipe bed, the trench is deepened and bedded. The pipes can then be lowered into the trench as a welded pipe string.

What is a trench in building?

A trench is a hollow cut into the ground, usually with parallel sides and which is typically deeper than it is wide. In construction, trenches are typically excavated for: Laying or getting access to services.

What is the purpose of trenching?

Trenching may be used to create new ditches for installing drainage, retaining walls, electrical or fiber conduit, sprinkler systems and gas, sewer and water lines. It can also be used to create replacement trenches to replace old sewer, water and drain lines with new materials.

What is trench excavation?

Trench excavation A trench is an excavation in which the length greatly exceeds the depth. Shallow trenches are usually considered to be less than 6 m deep, and deep trenches greater than 6 m. Trench, or footing, excavation is typically used to form strip foundations, buried services, and so on.

What is open face excavation?

When building a road across a hill slope, open face excavation is required. The purpose is to cut the slope to create a surface that is level or parallel with the sea level. If material from site excavations is not enough to fill the embankments, the engineer may order the contractor to import filling elsewhere.

What is meant by pipe laying?

1. The laying of conducting pipes underground, as for water, gas, etc. 2. (Polit. Cant) The act or method of making combinations for personal advantage secretly or slyly; – in this sense, usually written as one word.

How is a trench formed?

In particular, ocean trenches are a feature of convergent plate boundaries, where two or more tectonic plates meet. At many convergent plate boundaries, dense lithosphere melts or slides beneath less-dense lithosphere in a process called subduction, creating a trench.

What is the process of trenching?

TRENCH: An excavation in which material removal forms a narrow opening in the ground. Unlike large excavations, a trench is generally deeper than it is wide. All soil, equipment, and material surcharge loads are no closer in distance to the top edge of the excavation than the excavation is deep.

What is the open trench excavation method?

The open trench excavation method is used for one of three main reasons: 1. A New Sewer Pipe Cannot Be Pulled Through – This reason for open trench excavation is more about the mechanics in performing trenchless sewer work.

Which is more expensive open trench or trenchless sewer repair?

The open trench method is, on average, more costly than trenchless sewer repair as it requires more time, excavation and restoration to complete. In addition, open trench excavation may require the removal of street and sidewalk pavement which also increases the cost of the repair.

Can a new sewer line be pulled through a trench?

1. A New Sewer Pipe Cannot Be Pulled Through – This reason for open trench excavation is more about the mechanics in performing trenchless sewer work. Sometimes, the fastening materials around the joints of an existing sewer line are too thick and strong—or the coupling sleeves won’t break when “pipe pulling”.

What are the safety precautions for trenching?

Keep excavated soil (spoils) and other materials at least 2 feet (0.61 meters) from trench edges. Keep heavy equipment away from trench edges. Identify any equipment or activities that could affect trench stability. Test for atmospheric hazards such as low oxygen, hazardous fumes, and toxic gases when workers are more than 4 feet deep.