Introduction to pre engineering buildings - components

1. INTRODUCTION TO PRE
ENGINEERED BUILDINGS

2. Introduction
• A pre-engineered building(PEB) is designed and or
PEB 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.
• These buildings were pre-designed or 'pre-engineered'
into standard sizes, spans, bays and heights, and use
standard details for fixing cladding, roofing, gutters,
flashing, windows, doors etc taking advantage of
industrial practices of mass production of components
economically.

3. Cont…
• (PEB) is designed by a PEB supplier or manufacturer,
using sophisticated design software which takes into
account the strength and thickness of available steel,
the building loading criteria like wind resistance, snow
loading, seismic zone, and a host of other loads that
the building may be subjected to.
• Steel is the material of choice for design because it is
ductile and flexible. Steel members have high strength
per unit weight and the properties of the steel
members mostly do not change with time.
• The addition and alteration can be made easily in steel
structures.

4. A PEB structure

5. HISTORY OF PRE ENGINEERED BUILDINGS
• Walker Construction Company provided its original self-
supporting barrel roof concept in 1832.
• Construct warehouses to California during the gold rush in
1850.
• Similarly Hemming and Company supplied six churches to the
diocese of Melbourne (Australia) in 1853.
• These church buildings weights about 50 tons when packaged
and included a steel frame covered with galvanized corrugated
sheets.
• An air gap was provided between the exterior steel and the
interior wooden skin for air circulation.

6. Cont..
• During World War II, the need for "ready to erect" structures arose for use as
barracks and maintenance facilities that could be containerized and shipped.
• Pre-engineered Steel buildings, which could be bolted together and required no
welding at the site, were thus produced in significant quantities.
•
• By the end of the war, it was clear that the industry would not return to its pre-
war product offerings. Metal buildings were here to stay.
• The post-war construction boom offered an ideal opportunity to mass produce
buildings for a variety of non-residential industries.
• The industry started offering several "standard sizes" to meet demand. The
increase in standard sizes and the growing demand made prefabrication
uneconomical and gave way for custom designed buildings.
• At this time, still well before the computer age, the process came to be known
as the "pre-engineered" metal buildings (PEB).

7. Cont..
• The Indian Scenario: Pre-engineered metal buildings were introduced in
India in the mid- 1990s. This rapidly growing industry has enormous
growth potential in India.
• Steel buildings are typically safer than the conventional masonry structures,
especially in earthquakes because steel structures do not collapse.
• The safety of steel buildings is more readily visible if the steel building is
properly designed, bolted and diagonally braced.
• types of software used are MBS and STAAD PRO.
• MBS is more user friendly and has virtually unlimited potential and design
flexibility.
• the STAAD PRO software requires more manual inputs.
• From the availability of software, the Indian PEB industry is fully tuned to
world standards.
• In India, most PEB projects are managed by Consultants who may be
architects or engineers.

8. Cont…
• The construction of PEB in the place of Conventional Steel Building
(CSB) design concept resulted in many advantages as the members
are design as per bending moment diagram and thus reducing the steel
requirement.
• In this study, an industrial structure PEB Frame & CSB Frame is
analyzed and designed according to the Indian standards, IS 800-1984,
IS 800-2007.
• In this study, a structure with length 80m, width 60m,with clear
height 11.4m and having R-Slope 5.71 Degree for PEB & 18 Degree
for CSB is considered to carry out analysis& design for 2D frames .
• The economy of the structure is discussed in terms of its weight
comparison, between Indian codes (IS800-1984, IS800-2007) & in
between PEB & CSB building structure.

9. Cont…
• Three main types of PEB manufacturers are serving the Indian market – the
fully integrated global players with manufacturing facilities in India, domestic
integrated manufacturers, and many small scale manufacturers who either
own some sort of limited manufacturing facilities or get the components
manufactured by third parties.
• The Indian PEB industry is primarily driven by cost.
• Consultants use a rule of thumb whereby the weight of the building is
multiplied by a conversion factor that accounts for the price of steel and
fabrication costs to arrive at the project cost.
• This approach favors the small non-integrated players who have low
overheads and do not consider safety as their main priority.

10. ADVANTAGES OF PRE ENGINEERED BUILDINGS
• Construction time:
• Buildings are generally constructed in just 6 to 8 weeks after approval of drawings.
• PEB will thus reduce total construction time of project by at least 40%.
• This allows faster occupancy and earlier realization of revenue.
• This is one of the main advantage of using Pre-engineered buildings.
• Construction cost:
• The labour cost on PEBs is also less as most of the building comes partially constructed.
• In the case of industrial and commercial projects, prefabrication allows, minimization of
onsite workload,
• Majority of the work is carried out offsite, eliminating most of the onsite works such as
welding and bolting of connections, pre-assembling of smaller components and also a
reduction in the number of onsite lifting requirements.
• All these lead to a significant saving in project costs
• PEBs enable all this without any compromise on the quality.