Thumb rules for designing a Column layout | Civil Engineering

Guidelines to be followed for making a column layout

In this article, we will go through the essential thumb rules to be followed for giving a column layout. Of-course columns have to be designed in accordance to the total forces acting on the structure, but apart from that, it is essential for every Civil engineer and Architect to remember a few thumb rules so that they are prevented from making mistakes.

You can hire me for your structural design need. Contact me.

Three thumb rules to be followed are as follows:

  1. Size of the Columns
  2. Distance between Columns
  3. Alignment of columns

Minimum Size of RCC columns

The size of the columns depends on the total load on the columns. There are axial loads and lateral loads. Large beam spans induce bending moment not only in the beams, but also in columns which are pulled by the stresses in the beams. It is important to use advanced structural design software like ETabs or Staad pro. I highly recommend every structural designer learn these software. The thumb rules are for general designing in very small projects.

For this general thumb rule, we will assume a structure of G+1 floors high, using standard 6″ walls.

Minimum size of an RCC column should not be less than 9” x 12” (225mm x 300mm) with 4 bars of 12 MM Fe415 Steel.

These days the minimum I use in my projects is 9″ x 12″ (225 mm x 300mm) with 6 bars of 12 MM Fe500 steel. You can never go wrong with strong columns. I also recommend use of M20 grade concrete for the structure (ratio 1 part Cement : 1.5 parts Sand : 3 parts Aggregate with 0.5 parts water by volume). I recommend use of 8 MM stirrups at a distance of 150 MM center to center throughout the length of column.

This setup of 9″ x 12″ RCC columns is safe for G+1 Floors. There are a lot of other considerations, but this is just a thumb rule.

Read moreThumb rules for designing a Column layout | Civil Engineering

RCC Building Design and Construction | Structural Design

Step by step procedure to RCC building design | Design of RCC Structures

A building is composed of various structural components such as Foundations, Plinth beams, Columns, Beams, Slab, Staircase, Doors and Windows.

RCC Building Design
RCC Building Design

Design of Foundation | RCC Building Design

Foundation design is the structural component from where the RCC design is initiated. The foundation design guide discussed earlier includes in detail the design procedure for isolated column footing. Column footing is the most commonly used type of foundation. It serves a variety of different buildings.

  • Design of Foundation – the most commonly used foundation is Column footing.
  • Calculation of loads in Foundation Design Calculation of loads is very important for the purpose of structural design. This article outlines the thumb rules for the calculation of various loads in foundation design.
  • Types of Foundations This is a generic article on different types of foundations. It covers some commonly used shallow foundations and also explains pressure distribution under a foundation.

Design of Beams | RCC Building Design

Beams are mainly classified into two types:

  1. Doubly reinforced beam (most commonly used in RCC Construction)
  2. Singly reinforced beam
    A series of articles have been written for the design of Singly reinforced sections. The articles include basic definitions and formulas, understanding stresses and modular ratios, assumptions for singly reinforced sections, Design method 1, Design method 2, Moment of resistance and a number of solved numerical examples.

Design of Columns | RCC Building Design

Design of RCC columns

The article discusses the classification criteria for a column,  and design of different types of reinforcements for columns which include longitudinal, transverse and helical reinforcements.

Thumb rules for designing a Column Layout

The articles important thumb rules to be followed for column layout design. Three important thumb rules have been discussed.

  1. Size of the Columns
  2. Distance between Columns
  3. Alignment of columns

Read moreRCC Building Design and Construction | Structural Design

Calculation of loads for Column and Foundation Design | Structural Design

How to calculate the total loads on a column and corresponding footing?

This article has been written on the request from my readers. Engineering students generally get confused when it comes to calculating loads for column and footings design. The manual process is simple.

Types of loads on column

  1. Self weight of the column x Number of floors
  2. Self weight of beams per running meter
  3. Load of walls per running meter
  4. Total Load of slab (Dead load + Live load + Self weight)

The columns are also subjected to bending moments which have to be considered in the final design. The best way to design a good structure is to use advanced structural design software like ETABS or STAAD Pro. These tools are leagues ahead of manual methodology for structural design, and highly recommended.

In professional practice, there are some basic assumptions we use for structural loading calculations.

You can hire me for your structural design need. Contact me.

For Columns

Self weight of Concrete is around 2400 kg per cubic meter, which is equivalent to 240 kN. Self weight of Steel is around 8000 kg per cubic meter. Even if we assume a large column size of 230 mm x 600 mm with 1% steel and 3 meters standard height, the self weight of column is around 1000 kg per floor, which is equivalent to 10 kN. So, in my calculations, I assume self weight of column to be between 10 to 15 kN per floor.

Read moreCalculation of loads for Column and Foundation Design | Structural Design

Relationship between Structural and Architectural Design

  • Structural Engineering and Architecture are two different sciences that are inter-related. Structural Designing deals with the study of design of steel in a structure i.e., the internal skeleton of the structure that helps to keep the structure durable, sound and stiff.
  • Whereas Architectural Design deals with design of spaces meant for a particular function. It helps to create ambient environment that is pleasing to eye. The Architect designs the building keeping all the functional aspects in mind that are to be incorporated into the design and then they are executed by a Civil or Structural Engineer.

Inter-relationship of Architectural Design and Structural Design
Inter-relationship of Architectural Design and Structural Design

  • The structures and structural members are designed to meet the functional and structural aspects. Both the aspects are inter-related. The functional aspect takes into consideration the purpose for which the building or the structure is designed. The functional aspect includes the determination of the amount and arrangement of space necessary for the structure.

Read moreRelationship between Structural and Architectural Design