Introduction of PRE Engg Building
- The Steel industry is growing rapidly all over the world. Steel is widely used Building material in the construction industry.
- Nowadays steel structures getting more popularity because of its economy and faster construction. The owner of the example of steel structure is PEB building.
- In this article, you will get to know about pre-engineered buildings, its components, advantages and disadvantages.
- The PEB full form is Pre-Engineered Buildings. The Buildings which are Engineered at the factory and assembled at the site are known as pre-engineered buildings.
- The pre-engineered buildings are widely used for the construction of industrial buildings and warehouses metro stations factories and bridges etc.
- PEB buildings are the steel structures which are fabricated at the factory to the required size and dimensions. Pre-engineered buildings at transport it an assembled at site with bolted connections.
- Pre-engineered buildings are steel structures from which the structure members are constructed like columns, roof truss, purlins etc.
- Pre-engineered steel buildings are constructed using Steel built-up sections that are designed and fabricated in the factory and assembled at the site by using various bolted connections.
- The Pre Engineered buildings have more advantages as compared to conventional Steel buildings.PEB shed mostly used in the construction of industrial buildings.
- PEB construction is economical and easier in fabrication. PEB structure can be finished internally to serve the functions which are required in the design of low rise building.
Components of Pre Engineered Buildings
The pre-engineered building is constructed with different components and connections. Pre-engineered buildings consist of difference structural Steel members which are as follows
#1. Primary Frame
- The Primary frame which is used in PEB construction is an assembly of built-up sections which forms framing and consists of trusses or castellated beam.
#2. Secondary Structural Elements
- The secondary structural elements are cold-formed members in the different shapes such as Z and C etc.
#3. Roof and Wall Panels
- The tin Shades and curtain wall made up of Glass and rolled formed Steel is generally used in roof and wall panels.
#4. Sandwich Panels
- Sandwich panels are made up of three layers in which an all aluminium core is inserted between two aluminium sheets.
Components of Industrial Building
The different components of industrial buildings are as follows.
- Sag rods
- Principal Rafters
- Roof Truss
- Gantry Girders
- Column and Column base
- Girt Rods
Advantages of Pre Engineered Buildings
The various advantages of Pre-engineered building are as follows
#1. Quality control of construction:
- In the case of the pre-engineered building construction, all the structural members are made in the factory under the supervision of quality control engineer.
- The construction of Pre-engineered building is less expensive as compared to another type of buildings. Pre-engineered buildings save designing and manufacturing cost.
#3. Less Maintenance:
- The maintenance cost which is required for the pre-engineered building is very less as compared to the conventional steel buildings because of the use of high-quality paint.
#4. Time Required for PEB Construction
- The time required for pre-engineered buildings construction is less due to the design of the structural components using advanced software.
#5. Warranty Period of Pre Engineered
- The warranty period of Pre-engineered building is 20 years given by the manufacturers.
#6. Erection of Pre Engineered Building
- The erection of Pre-engineered building components is very fast and easy due to the use of Pre-manufactured and skilled labour in the pre-engineered building construction.
Disadvantages of Pre Engineered Buildings
There are also some disadvantages of Pre engineered buildings which are as follows.
- This type of structure can be attractive when it is left exposed.
- The parts of the pre-engineered buildings are susceptible to corrosion.
- The insulating of the building will furthermore increase the construction cost.
Use of Pre Structure
The Pre-Engineered buildings are used for the following structures.
- For the Construction of Low Rise Industrial Buildings.
- Power Plants
- Airport Hangers
- Parking Lots
How Pre Engineered Building Is Better Than Conventional Building?
- Pre-engineered metal buildings have efficient design due to its integral framing system whereas the conventional Steel buildings have a less precise design which requires more time.
- Pre-engineered Steel buildings are 10 to 20% lighter than conventional buildings.
- PEB Construction and erection is faster and simple as compared to conventional Steel buildings.
- PEB Buildings required light equipment for construction, and conventional building required more labour and heavy equipment for Construction.
- Pre-engineered buildings have good resistance against systemic actions due to lightweight structure whereas conventional buildings cannot stand against systemic forces because of heavy structure.
Applications of Pre Engineered Buildings
- Gas Stations
- Vehicle Parking Sheds
- Aircraft Hangars
- Metro Stations
- Indoor Stadium Roofs
- Outdoor Stadium Canopies
- Railway Platform Shelters
Pre Engineered Building Design Calculations
The pre-engineered building design calculations are done by the main framing of the engineered Building System by the Stiffness Matrix method.
The design cycle consists of the following steps.
- First upon set up the section of the required size and breast locations based on the geometry and loading.
- Then calculate the shear moment and axial force at each point for each load combination.
- Identify and compute allowable share stress and allowable bending stress in the compression and tension at each analysis point.
- Calculate the corresponding stress ratio for shear and axial and bending based on the allowable stresses.
- Design the optimum location and check whether the predicted size is as per the manufacturing constraints or not.
- At the end of the design process, the analysis of the structure is done for further optimization.
Load Calculations for Pre-Engineered Buildings
The load calculations for pre-engineered buildings is that load considered are the same as for general building structure.
#1. Dead Load Calculations
- The dead load includes self-weight of purlin, roof and wall sheeting and other structural components.
#2. Live or Imposed Load Calculations
- This type of load should be considered as per IS 875 (Part 2)
#3. Wind Load Calculations:
- Considered the basic wind speed as per the space of the structure. The wind pressure is calculated as per the IS 875 (Part 3)
#4. Seismic Load Calculations
- Earthquake loads can affect the whole structure so that it is necessary to consider it during the designing.
#5. Load Combinations
- As per IS 1893 2002 (Part 1), 7(DL ± LL), 7(DL ± EL) , and 3(DL + LL ± EL)