Civil Engineering Projects – Page 8 – Construction Technology, Design and Engineering

Causes of Foundation Damage and Retrofitting | Settlement in the ground

December 16, 2011 by Designer

Causes of Foundation damage and Retrofitting

In one of my previous articles, we discussed various steps in which the survey of the foundation has to be done in order to be considered for retrofitting.

In this article, we will discuss various reasons or causes for the damage of the foundations.

Types of foundation damage can be classified as follows:

Erosion

Rot

Insects

Moisture damage

Settlement in the ground

Frost heave/adfreezing

Alum shale

Now we will move on with the discussion in detail on the types of foundation damage occurring due to Settlement in the ground.

Lowering in the Groundwater level

When the buildings are built on compressible soils, the resulting stress on the soil causes the soil to compress. Raft foundations are used in these kind of soils.

Since the soil undergoes compression the upper portion of wooden piles rot when groundwater level sinks.

There are various conditions which can cause the changes in the groundwater level or pore water pressure. They are as follows:

Ice Static Rebound

Dewatering (seen in cities)

Ditches and pipes below the groundwater level

Deep Foundations and Basements (causing further drainage of the ground

Tunnelling

By the removal of foundation sills

Construction of non-permeable surfaces such as roads, pathways causing the least amount of natural precipitation

Use of deciduous trees should be avoided in areas with low groundwater. They require a lot of water for their growth. They pull all the water that is available around them causing the lowering of groundwater.

Building Materials | Use of Carbon-negative Cement in Building Construction

December 13, 2011 by Designer

Carbon-negative cement | New revolutionary Building material

Carbon-negative cement…?? Sound different, doesn’t it?

Have you ever realized how much carbon is emitted because of using concrete in the construction of buildings, highways, dams, bridges etc?

Well, here’s an answer to that. It is found that out of the 100% carbon dioxide emissions, 5% of the emissions are caused by human activities. Majority of the carbon emission is caused by usage of concrete in the constructions. How? Cement is an indispensible ingredient used for making concrete. Cement is made by baking limestone and clay powders under intense temperatures (high temperature). The intense heat which is required for the production of cement is achieved by burning of fossil fuels which in turn release large amount of carbon dioxide into the atmosphere.

Building Construction | We can just imagine to what extent the carbon dioxide would be released into the atmosphere.

Carbon dioxide is also released when the conversion of limestone takes place in the kilns. This conversion is called “Calcination”. It has been observed that the amount of carbon dioxide emitted during calcination is much higher than that which is released due to burning of fossil fuels.

Recently, a British company called “Novacem” came up with this concept of manufacturing ‘carbon-negative’ cement that absorbs more carbon-dioxide than it emits over its entire life cycle.

Secondary lighting systems | Lighting Techniques

November 12, 2011 by Designer

Lighting systems | Illumination Techniques

Lighting Systems comprises of two main systems:

Both of these lighting systems are to be integrated together in designing the lighting for any space.

Earlier, we discussed “Primary Lighting Systems”. Now we will move on with the discussion on Secondary Lighting Systems.

Shadow effect achieved with the help of wall mounted Light. Effects of Lighting could be really amazing...!

Secondary Lighting Systems

1. Accent lighting- 15 times more than task lighting

2. Effect lighting- no functional value

3. Decorative lighting

4. Architectural lighting

5. Mood lighting

Calculations for Overhead Water tank | Building Construction

November 6, 2011 by Designer

Design of Overhead Water Tank | Design of RCC Structures

As per NBC (National Building Code, 2005) standards,

Water required per person per day = 150 litres

Drinking water = 4litres per person per day

Calculation for an overhead water tank for a 3 BHK Villa:

Let us assume the average family size = 5 persons in the house

Water required for daily chores per person per day as per NBC norms;

150 x 5 = 750 litres

Drinking water required:

4 x 5 = 20 litres

Total quantity of water required = 750+20 = 770 litres

Volume of water = 770/1000 = 0.77 cubic metres

Height of Collimation and Rise and Fall Method | Methods of Levelling

October 30, 2011 by Designer

Methods of Levelling | Guide to Surveying and Levelling

In this article, we will discuss two important methods of Levelling. We will also study these Methods with the help of Numerical Examples in our successive articles.

There are two Methods of Levelling:

Height of Collimation Method
Rise and Fall Method

Height of Collimation Method

This method is simple and easy.

Reduction of levels is easy.

Visualization is not necessary regarding the nature of the ground.

There is no check for intermediate sight readings;

This method is generally used where more number of readings can be taken with less number of change points for constructional work and profile levellings.

Principles of Chain Surveying or Linear Surveying | Civil Engineering

October 30, 2011 by Designer

Chain Surveying or Linear Surveying | Surveying and Levelling

It is the method of land surveying in which only linear measurements are made.

Chain surveying requires chain, tape and ranging rods.

Chain surveying is not suitable for large areas having many details.

(The term “details” means a natural or manmade features at or near the ground surface).

It consists of the following:

Hard details

Hard details include buildings, roads, walls etc.

Soft Details

Soft details include river, vegetation, trees etc.

Overhead details

Overhead details include power and telephone lines.

Underground details

Underground details include survey of water mains, sewer etc.

Principles of Chain Survey

A triangle is a simple figure which can be plotted from the lengths of three sides even if the angles are not known.

In chain survey, the area to be surveyed is divided into a framework consisting of triangles.

Guide to Doubly Reinforced RCC Beam Design

October 30, 2011 by Designer

RCC Beams

RCC beams are cast in cement concrete reinforced with steel bars. Beams resist compression and tensile forces and add rigidity to the structure.

Beams generally carry vertical gravitational forces but can also be used to carry horizontal loads (i.e., loads due to an earthquake or wind). The loads carried by a beam are transferred to columns, walls, or girders, which then transfer the force to adjacent structural compression members. In light frame construction the joists rest on the beam.

In this article, we are going to discuss types of beam construction and RCC design of simply supportedreinforced beam.

Simply supported RCC beam construction is of two types:

Singly reinforced beam
Doubly reinforced beam

The Magnificient Victoria Tower, Stockholm, Sweden

October 30, 2011 by Designer

Sweden is one of the most prosperous of Scandinavian nations in Europe. It has a long history of traditions and cultural heritage. Sweden is famous for its amazing Swedish Cheese. Stockholm is a beautiful city, and its latest jewel would be the new Victoria Tower. It would be the second highest building in Stockholm after the Kaknästornet.

The Magnificient Victoria Tower, Stockholm, Sweden

The name “Victoria” comes from’ the crown-princess of Sweden. Construction on this tower began in May 2009. There was a lot of debate about the final height of the building. This tower would be operated by Scandic Hotels.

Is it possible to construct an Earthquake-proof building?

October 30, 2011 by Designer

Rapid violent shaking of the Earth’s surface caused by rapid movement of the Earth’s rocky outer layer is known as an Earthquake. Earthquakes occur when energy stored within the Earth, usually in the form of strain in rocks, is suddenly released. Elastic Rebound Theory lays down the phenomena that causes earthquakes. It is mostly related to slippage of active fault-lines in the earth’s crust.

Earthquake Effects on Buildings

The motion along the fault is accompanied by the gradual buildup of elastic strain energy within the rock along the fault. The rock stores this strain energy like a giant spring being slowly tightened.

Methods for Correcting the bearings affected by Local Attraction

October 30, 2011 by Designer

Local Attraction | Methods for Correcting the bearings affected by Local Attraction

The deflection of a magnetic needle from its true position due to the presence of magnetic influencing material such as iron ore, magnetic rock, underground pipeline, electric cables, iron pipes, electric poles in its vicinity is called “Local Attraction”.

Methods of Correcting the bearings

There are two methods of correcting the bearings affected by local attraction:

Included angle Method
Error Computation

Included angle Method

In this method, the included angles of the traverse are calculated first, then starting from the line which is unaffected by local attraction and using the included angles, the corrected bearings of the traverse are computed.

Error Computation Method

In this method, the direction and the amount of local attraction at each survey station is determined.

Then starting from the line which is unaffected by local attraction, the corrected bearing of the traverse are computed.

This method is more accurate than the included angle method.

Hence it is adopted by most of the surveyors.