February 2012 – Civil Engineering Projects

Drainage and Dewatering | Building Construction

February 7, 2012 by Designer

Introduction to Drainage and Dewatering

In this article, we will discuss and classify drainage and dewatering in brief.

What is drainage?

As the name itself suggests, drainage is the process in which the free water is removed with the help of gravity in order to maintain stable soil conditions.

Drainage can be classified into two categories:

Surface drainage
Sub-surface drainage

What is Surface drainage?

The water that runs on the surface of the ground is collected and or diverted into a water body.

Sub-surface drainage

It is the collection and disposal of ground water. It is also called as dewatering.

What is dewatering?

The process in which the water is removed from a foundation pit;

when it is situated below the ground water table or
when it is surrounded by a coffer dam.

Conduits | Building Construction

February 3, 2012 by Designer

Construction of Conduits | Civil Engineering

In the previous article, we discussed “Types of Underground Conduits”. Now we will proceed with our discussion on “Construction of Conduits”.

Underground conduits can also be termed as buried conduits. They are constructed in variety of shapes with different materials used for construction.

Load on the conduit

The characters of the conduit determine the load withstanding capacity of the conduit. They are as follows:

Material of the conduit
Shape
Type of the support

For example:

If we take the example of a concrete conduit (rigid material), the load that the concrete conduit can withstand would depend on the following:

Strength of the concrete pipe
Quality of the foundation bedding

How to determine the strength of the conduit?

A three edge bearing test has to be conducted in order to determine the strength of the conduit.

This test simulates a very severe loading condition which would rarely occur in the actual conduits. This helps us determine the maximum load the conduit can take. It has been seen that the conduits can take greater load than that obtained in the test.

Types of Underground Conduits | Civil Engineering

February 2, 2012 by Designer

Underground Conduits

What are conduits?

Conduits have different meanings in different subjects.

For example:

Geographically, conduits could refer to a channel carrying water, underground tunnel or waterway (river or canal).

In terms of electrical systems, it may refer to an electrical conduit, HVAC (duct) etc.

We are referring to the conduits which is laid underground and used for variety of purposes.

For example:

Sewers
Drains
Culverts
Water mains
Gas lines
Electrical cables
Telephone lines

Construction of Earth Tunnels | Building Construction

February 1, 2012 by Designer

How to construct Earth Tunnels?

In this article, we will discuss the procedure of the construction of the Earth Tunnels in a stepwise manner. It will be useful to you all in understanding and remembering the procedure.

We would be studying the construction method of tunnel in two types of soils:

Firm soil
Soft soil

Step1:

Excavation of the ground from below. It is similar to the process used in mining.

Step2:

Check the type and bearing capacity of soil. The method of construction would depend upon the ability of soil to support itself temporarily during construction.

It also depends on the ability of the soil to withstand the magnitude of pressure imposed on it during construction.

Step3:

It is important to understand the factors that affect these parameters. They are as follows:

Depth of the tunnel
Diameter of the tunnel
Properties of the soil
Ground water table

Support to the Tunnel

Most of the time, the tunnel requires temporary support during construction and a permanent support after construction.