Updated June 8th, 2018
We have considered “Sub-structure” as 3rd work phase of building construction in our tutorial series. We left a work-phase that is Ground Work. Because we discussed that topic several times here on this blog. You can read them in following links –
In this post, we’ll discuss sub-structure of a building.
Sub Structure: The 3rd Work-Phase of Building Construction
First of all, we should know “what is sub-structure”?
“The structure below ground level can be defined as sub-structure”.
Someone defined sub-structure as “the structure which can’t be visible”.
“The structure up to plinth level is defined as sub-structure” in many engineering books by specialists.
From the definition of Sub-structure, we can say it consists of the following parts of the building –
- Short Column
- Grade Beam
Foundation: foundation also called base. A building completely stands on it. So it is the most important part of a building. There are many types of foundations we can make to build a building. Please see this post to know more about the foundation.
Short Column: Theoretically, short columns are those which effective length to least lateral dimension ratio doesn’t exceed 12. Generally, A column between foundation and grade beam is called short column or neck column.
Grade beam: grade beam doesn’t carry any vertical load. It just ties columns to prevent lateral movement. That’s why this beam is also called Tie beam. Sometimes ground slab rest on grade beam and thus carries vertical loads. Then it is called ground beam.
Dear reader, when I started this building construction tutorial series that time I expected to publish two or three posts in a week. But I was extremely busy on some of my projects. That’s why I haven’t published any post for a long time. I’m sorry for that. From now I’ll publish regularly, at least one post of this tutorial series in a week with some other important posts.
However, we already know from this post that ground floor slab can’t be included in sub-structure as the ground floor slab is visible and ground floor slab is built above the plinth level, yet someone includes ground floor slab in sub-structure if it is built on the ground.
I’ve discussed briefly sub-structure in this post. I’ll discuss details about each item of sub-structure later in this tutorial series. Our next post of this tutorial series will be about superstructure. To subscribe via email to get an immediate update.