Calculations for Overhead Water tank | Building Construction

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

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Guide to Doubly Reinforced RCC Beam Design

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.

Doubly Reinforced Beam
Doubly Reinforced 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

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Is it possible to construct an Earthquake-proof building?

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.

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Foundation Damage and Retrofitting

Causes of Foundation damage leading to 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.

Cracks in foundation
Cracks in foundation

Types of foundation damage can be classified as follows:


  1. Natural rock
  2. Brick



Moisture damage

  1. Frost wedging
  2. Salt bloom

Settlement in the ground

  1. Groundwater lowering
  2. Limited bearing capacity of the ground (land)
  3. Uneven depth of the bedrock (varying bearing capacities of the soil in the same patch of land)
  4. Excavations performed below the foundations and poor quality of backfill
  5. Increased load on the ground leading to failure
  6. Damage to the neighbouring houses
  7. Increased load
  8. Horizontal movement occurring in the ground

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Specifications for RCC Construction | Building Estimating and Costing

In my earlier articles, I have discussed types of specifications and various purposes for which specifications are to be given. Most of the constructions of various types of buildings are RCC constructions. In this article, we are going to discuss in detail about the specifications that are to be necessarily given for carrying out RCC (reinforced Cement Concrete) constructions.

RCC specifications
RCC specifications

RCC Specifications

  • Shuttering shall be done using seasoned wooden boards of thickness not less than 30mm.
  • Surface contact with concrete shall be free from adhering grout, nails, splits and other defects.
  • All the joints are perfectly closed and lined up.
  • The shuttering and framing is sufficiently braced.
  • Nowadays timber shuttering is replaced by steel plates.
  • All the props of approved sizes are supported on double wedges and when taken out, these wedges are eased and not knocked out.
  • All the framework is removed after 21 days of curing without any shocks or vibrations.
  • All reinforcement bars conform IS specifications and are free from rust, grease oil etc.
  • The steel grills are perfectly as per detailed specifications.
  • The covers to concrete are perfectly maintained as per code.
  • Bars of diameter beyond 25mm diameter are bent when red hot.
  • The materials proportion should be as per the specifications of the concrete.

Number of Cement bags required for a specific cement concrete ratios

  • For cement concrete of ratio 1:1:2(1 cement:1sand/coarse sand:2graded stone aggregate) require 11no bags of 50kg.
  • For cement concrete of ratio 1:1.5:3 require 7.8no bags of 50kg.
  • For cement concrete of ratio 1:2:4 require 6 no bags of 50kg.
  • For cement concrete of ratio 1:3:6 require 4.25no bags of 50kg.
  • For cement concrete of ratio 1:4:8 require 3.2 no bags of 50kg.
  • For cement concrete of ratio 1:5:10 require 2.50 no bags of 50kg.
  • For cement concrete of ratio 1:6:12 require 2.25 no bags of 50kg.

New trends in the Color schemes and Materials of Design

New Trends in the choice of Color schemes

The new trends in Furniture design has brought a concept of new choice of color schemes depending on the type of ambiance to be created. Along with maintaining the aesthetic aspect, new materials and new lighting techniques have also come up.

Two trend streams emerge; one following the ‘international’ look of pale sophistication, with beiges, creams and white, offset by stark black. A parallel stream throws into focus the bright new color palette with the nouveau chic fuschia, lime green, aubergine and aqua.

Trendy furniture Design
Trendy furniture Design

The trade and architect community notice a bifurcation in usage with designers selecting the former for more elegant, more ‘serious’ spaces such as offices, or for general use spaces such as lounge areas in hotels, while residential spaces, use color to project the personality of the owners. The bright colours give a happy office look. Finance and Insurance offices are serious and very professional offices can have lighter colors that add richness to the space whereas other offices could use shades of yellow and light brown.

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Development in Structural Systems in Postmodernist Period

Evolution of Structural Systems in Postmodernism

Before 20th century, there were three great developments in structural systems.

Bulk Active structure is classified as followed:

  1. Post and lintel
  2. Arch system

Dome and vault construction (either in the form of bulk, employing plastic materials i.e. concrete, hardening into a homogeneous mass or the thrust type, in which the loads are received and counterbalanced at definite points; steel-glass skeleton system.


St. Peter's Dome
St. Peter's Dome


After World War II, the analysis of building types provides information behind each of the greater styles. This can easily be understood that it was not merely a trend, but a period of serious and required experimentation directed toward answering the needs of a specific way of life. In the era, most of the construction work was dominated by sustainable building design, construction and using materials in ways that minimize toxic production methods and in using natural sunlight for energy and natural air movement and water for cooling, climate, methods of labour, available materials, and economy of means thus impose their dictates.

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Guide to Design of Simple Beam | Design of Steel Structures

Design of Simple Beam

A member carrying loads perpendicular to its axis is defined as a beam.

For a simple floor beam, I-sections are used.

M/I = (sigma) /y

M = (I/y)(sigma)

I/y = Z (section modulus)

Therefore, M = z(sigma)

When beams are loaded, bending stresses are developed at all sections.

The bending stresses developed in beams can be determined by the equation theory of simple bending.

For laterally supported beams, the permissible bending stress in tension as well as in compression should not exceed (sigma)bc or (sigma)bt = 0.66fy

For laterally unsupported beams, the permissible stress in bending compression is calculated by using tables from the the IS code book (IS:800).

Load carrying capacity of the Beam

From structural steel tables for the given beam, the section modulus (Zxx) is obtained.

Depending upon whether the beam is laterally restrained or unrestrained; the value of permissible stress in bending compression ((sigma)bc) is calculated.

The moment of resistance of the beam is found out.

MR = Zxx .(sigma)bc

Equating the moment of resistance to the maximum bending moment equation, the total load (w) the beam can carry is calculated.

Practical Problems related to Construction on Site | Building Construction

General Construction Problems on Site

Getting fine aggregate free from dust, clay, salts etc.

  • Silt clay and silt (sizes below 70M)
  • (sizes below 4-5M)
Practical Construction Problems on site
Practical Construction Problems on site

Being small, they absorb lot of water. Water available for cement hydration is less, leaves pores. Clay and silt affect the gel formation. As it does not participate in gel formation, denser cone is not formed. Durability is reduced.

Clay particles tend to flocculate due to cohesion and under stress, may tend to break resulting in voids, therefore weak concrete. These clay particles coat the coarse aggregate, thus presetting the bond between the coating of cement and coarse aggregate. This seriously affects the strength.

Therefore, sand containing silt and clay should be summarily rejected or through washing of sand but expensive.

Quality of water

  • Many it is hard water that is available at site. For food concreting job, it requires portable soft water, as the salt contents in hard water may affect the gel formation.

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Underwater Lighting Techniques | Aqua Architecture

Under water lighting deals with the lighting systems placed inside water entities like swimming pools , fountains , etc , and some times even in smaller areas like Jacuzzis . This aspect of lighting mainly depends on the various physical properties of water ( refraction , reflection etc of stand still and moving water). Under water lighting also deals with the effects of lighting placed above water , on and in water.

Figure showing a water fall lit from beneath showing the ‘Glowing steps ‘ effect
Figure showing a water fall lit from beneath showing the ‘Glowing steps ‘ effect

Under water lighting also deals with the effects of lighting placed above water , on and in water.

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