In building designs we have to mainly structurally design, (1). Slabs, (2). Beams (3).Columns (4). footings and (5).Staircases. For the easiness of Beam analysis, we can use Prokon Software or any other software. For column design we have to go for a frame analysis. For that also we can use the Prokon software for our easiness. We can also use Sap 2000 or ETABS software for this purpose.
Load calculation is a main part in the initiation of the designs. We have main two types of leads.
(1). Dead loads
(2). Live loads
Dead loads are the loads coming from still permanent things of the building. For that we can get the use of Reynold's Handbook. There are two books of them. The red color Reynolds's Theory handbook and Blue color book: Reynold's Example handbook. Live loads are the loads that are coming from moving things such as humans. pets, furniture, water tank water, machines, cupboards, partitions, etc. For the live load calculations we can use BS 6399. We can use Reynolds Theory handbook too. Live loads are also called Inposed loads or Movable loads.
In the analysis part of the structural designs we have to deal with Bending moments, Shear Forces, Axial Forces and Stresses. These parameters can be easily obtained by software packages such as prokon or Etabs or Sap 2000. And also we can find these parameter values manually with the help of the basic principals. But it takes time. According to the british standards, for the structural design, we use BS8110. There are 3 parts.
BS8110-Part 01 - is used for Ultimate limit state design.
BS8110-Part 02- is used to Check the serviceability Limit State Designs such as Crack width calculations, Deflection Checks and Vibration Limits etc.
BS8110- Part 03 - is consisted with all the design charts needed for the beam design and column designs.
In the design codes or manuals, there are, Clauses, Tables, Figures and Equations. For an example, Cl3.4.4.4 is used to calculate the K value using the Moment value, element sizes and the concrete strength value for beam or slab element designs. Table 3.27 is used to check the minimum steel requirements. Figure 3.25 is used for Simplified rule for the Reinforcement curtailments.
When you come to the detailing part after the analysis part, We can use several books as manuals.
(1). Society of Structural Engineers Detailing Manual book
(2). Robin White's Detailing Manual Book.
As an example Fig 3.25 and Figure 3.24 of the above first book have mentioned how to use the simplified rule when detailing the reinforcement bars,
After the design we have to Prepare a bar bending schedule. That is the list of the reinforcement bars with their specified needed lengths and shapes and quantities of them. That will ease the construction and also in the planning stage. We can use BS 4466 or BS 8666 for preparing the bar bending schedules. Usually the prints of structural drawings are taken on standard size pages such as A1, A2 and A3 sizes. We can use drafting software such as Autocad, ZWCad, etc for drafting purposes.
And also when dealing with structural drawings in the construction field, It will be essential most of the time to prepare Rate Analysis and Bill of Quantities (Engineer's Estimate) for the easiness of the projects.
In the Structural Designs according to the British standards we can refer below books and I recommend those for a good guidance.
(1). S.S.Ray - Concrete design book
(2). A.H. Allen - Concrete Design book
(3). Mosely and Bunghey Concrete design book
(4). Kong and Evan Book/
(5).W.T.Moody- Moments and Reactions for rectangular plates
Hope you got a good explanation for the introduction to Structural Design and Say with me for step by steps to Structural Design of Building Structures.
Thank You!
Eng: Isuru S. Amarasena
Chartered Civil Engineer
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