PRE-FABRICATED STEEL STRUCTURE DESIGN TUTORIAL: PART 1

In this tutorial I want to teach practical design. so my tutorials are project based. I have planned to discuss different building. Those are one storied building pitched roof building, two storied building having a pitch roof, multi storied building etc.

My tutorials will contain load calculations, design by software, drawing guideline, practical design experience share etc.

At first, I will design a single storied Pre Fabricated Steel Building.

Figure 1

Building Information

Building Dimension: 60'X40' (See column layout)

Figure 2

Clear Height: 15' (see typical section)

Wall System: 5 inch brick wall and wall sheet (see typical section)

Figure 3

Roof slope: 1:10

Wind Bracing: Roof and wall bracing

Roof cladding: 0.47 mm thick steel sheets (color coated)

Wall cladding:0.47 mm thick steel sheets (color coated)

Building Location: Dhaka, Bangladesh.

Loads on all buildings are applied in accordance with BANGLADESH NATIONAL BUILDING CODE (BNBC)-2006

Bay spacing (c/c distance of main frame): 20' (6100 mm). See Article "Selection of column spacing"

Here single frame analysis is done.

Load Calculation

Dead Load Calculation

There are three types of dead load will be applied in this structure.

1. Self weight of the main structural member (column & rafter)

2. Roof sheet weight

3. Purlin weight

Self weight of the main structure will be calculated by the software (Staad.pro V8i).

Roof sheet weight is calculated by the following:
=(0.47/1000)*(7850/0.82)*(9.81/1000) KN/sq. m.
=0.044 KN/sq m.
Here, 7850 is unit weight of steel in kg/cu. m.
When sheet is folded by machine it's width is generally decreased 18 %. That is why it is divided by 0.82.

Purlin weight is calculated by the following:

Let us purlin section is according to figure 4. Nos of purlin in a frame is =(40*304.8)/1200=10(around), So, spacing of purlin is =(40*304.8)/10=1219.20 mm=1.2192 m.

Figure 4

So, weight of purlin is
=[{(18*2+60*2+250)/1000}*(2.5/1000)*(7850*9.81/1000)*(1/1.2192)] KN/sq m.
=0.065 KN/sq m.

So, Total weight of sheet and purlin is
=(0.044+0.065) KN/sq m.
=0.109 KN/sq m.
Applying bay spacing
=(0.109*6.1) KN/m
=0.66 KN/m

[TO BE CONTINUED]