pre engineered building

In structural engineering, a PreEngineered Building (PEB) is designed by a PEB supplier or PEB manufacturer, to be fabricated using best suited inventory of raw materials available from all sources and manufacturing methods that can efficiently satisfy a wide range of structural and aesthetic design requirements. Within some geographic industry sectors these buildings are also called pre-engineered metal buildings (PEMB) or, as is becoming increasingly common due to the reduced amount of pre-engineering involved in custom computer-aided designs, simply engineered metal buildings (EMB).

Components of PEB

Pre Engineered Buildings consist different steel structural member which are as follows,

• Primary Frame:
  Primary framing of a PEB is an assembly of builtup I-Shaped steel members & that framing consist trusses or castellated beams etc.
• Secondary Structural Elements:
  It is actually Cold Formed Members, which can be in diff. shapes like “Z”, “C” etc. In general known as “Purlins”.
• Roof & Wall Panels :
  Tin shades & Curtain Wall made of Glass & Roll-formed steel sheets usually comes in this category.
• Sandwich Panels:
  Sandwich Panel is made of three layers , in which a non-Aluminum Core is inserted b/w two aluminum sheet.
• Other Accessories:
  Mezzanine floors, Bolts, Insulation, etc.

Types of Span

Design Methodology

• Method Used :
  Stiffness Matrix Method
• Standard Code used :
  • AISC
  • ASCE
  • IS : 800
• Software used :
  Staad.Pro v8i, ETABS, RAM Steel
• Load Considerations & their Calculations :
  Loads considered in the PEB design are same as for general building structure. These are as follows ,
  • Dead load Calculations :
    It includes Self Wt. of Purlins , Roof & Wall Sheeting , insulation material & other structural component.
  • Live / Imposed Load Calculations :
    It should be Considered as per given in IS 875 (Part 2 ) for diff. type of
  • Wind Load Calculations :
    Consider the Basic wind Speed as per Area of that particular structure. Design wind Pressure is calculated as per IS 875 (Part 3) . Wind Load on Roof can be UDL & calculation for this can be done as per IS875(Part 3)
  • Seismic Load Calculations :
    Earthquake Loads affect the design of structure in areas of great seismic activity. The seismic load can be calculated as per IS 1893-2002(Part 1).
  • Other Moving Loads :
    It can be Moving EOT Crane load or Mono Rail etc.

• Load Combinations :
  As per IS 1893 – 2002 (Part 1)
  • 7(DL ± LL)
  • 7(DL ± EL)
  • 3(DL + LL ± EL)
• Mechanism :
  For diff. Load Combinations structure should be checked by considering Internal work equal to External work and We will consider the following Mechanism,
  • Beam Mechanism
  • Sway Mechanism
  • Gable Mechanism
  • Combined Mechanism

• Checks Made :
  • Effect of Axial Force :
    Max. Load should be checked with allowable load bearing of the section. As, Max. Axial Force in Column/Axial Load causing yielding < 0.15
  • Check should also be made for Local Buckling of Flanges & Webs.
  • Check for the Effect of Shear Force :
    Shear Force at the end of the Girder should be less than the Max. Shear Capacity.
• Design Procedure :
  It consist some steps, which are as follows,
  • Based on the geometry, set up section sizes and brace locations.
  • Loading Calculations :
    Specify the Load case & load combinations for designing of the framed steel structure.
  • Calculate S.F. & M. for each load case detail
  • By using the Standard Codes, check and compare the calculated stress with the allowable or Permissible Shear Stress & Bending Stress values.
  • Design the optimum Splice Location.
  • Made check for predicted section that it satisfy or fail for any loading conditions.
  • Now, by ending the design an analysis is run to achieve flange bar optimization.

Building Accessories