SEMINAR ON ³PRE ENGINEERED BUILDINGS´ BUILDINGS´ Concept , Design & Construction
BY KUMBAR BHANU PRAKASH,
M.Tech 1st Sem, Structural Engineering, DSCE, B¶lore.
INTRODUCTION
Pre-determined inventory of raw materials that can satisfy a wide range of structural and aesthetic design requirements. Pre-Engineered Buildings can be adapted to suit a wide variety of structural applications, the greatest economy will be realized when utilizing standard details. An efficiently e fficiently designed Pre-Engineered Building can be lighter that the conventional steel buildings by up to 30%.
These
The
are the structures basically produced at the factory with high tensile steel material by collecting complete information of the shed/building (viz; Length, Width, Height etc,). entire design of column, rafters and other accessories is based on International structural standards and involve high technical welding and quality production.
BUILDING COMPONENTS 1. Prime Steel Framing Systems
2. Secondary Systems Secondary structural steel framing system refers to purlins, girts, eave struts, wind bracing, flange bracing, base angles, clips and other miscellaneous structural parts.
3.
Coated Steel Sheet Products
Colour
coated sheets provide excellent resistance to corrosion and hence has become the most preferred material for a wide range of construction uses, particularly roofing and walling.
4.
Decking Sheets
Flordec Sheets (Corrugated Sheet for Composite Floor)
Flordec
decking sheets are composite floor systems, constructed with cold-rolled corrugated steel decking covered with concrete.
Insulation (PEBI)
Uniformly textured inorganic glass fibers bonded together by a non-water soluble and fire-retardant thermosetting resin. It is free from coarse fibers and shot due to its mineral composition. PEBI is non-toxic and not hazardous to health.
DESIGN OF PRE ENGINEERED BUILDINGS
The
main framing of PEB systems is analyzed by the stiffness matrix method. The frame data is assembled based on number of frame members, number of joints, number of degrees of freedom, the conditions of restraint and the elastic properties of the members. The overall joint stiffness matrix is obtained based on the above frame data by summation of individual stiffness matrices considering all possible displacements. The load vector is then generated based on the loading data and the unknown displacements are obtained by inverting the overall joint stiffness matrix and multiplying with the load vector.
Design Codes
AISC: American institute of steel construction manual
AISI: American iron and steel institute specifications
MBMA: Metal building manufacturer¶s code
ANSI: American national standards institute specifications
ASCE: American society of civil engineers
UBC: Uniform building code
IS: Indian standards
Latest International Codes & Deflection
Design Criteria
DESIGN METHOD: Allowable stress design method is used as per the AIS C specifications.
DEFLECTIONS: Unless otherwise specified, the deflections will go to MBMA, AIS C criteria and standard industry practices.
PRIMARY FRAMING: Moment resisting frames with pinned or fixed bases.
SECONDARY FRAMING: Cold formed Z sections or C sections for purlins or girts designed as continuous beams spanning over rafters and columns with laps.
LONGITUDANAL STABILITY: Wind load on building end walls is transferred through roof purlins to braced bays and carried to the foundations through diagonal bracing.
DESIGN SOFTWARE The
latest software that is used for design is STAAD 2007.
ERECTION SYSTEM
1. 2. 3.
1. 2. 3. 4.
Preparation for Erection Pre Erection checks Receiving Materials at site Unloading Containers Erection of the Framing Preparation of the First Bay Main frames Mezzanine floors Crane Beams
Sheeting & Trimming
Sheeting preparation
Sheeting the walls
Sheeting the roofs
Miscellaneous trimmings
Fascia
Self weight
30% lighter
Self weight More heavy
Primary Member is tapered section
Primary members are Hot rolled ³I´ section
Secondary members are light weight rolled framed ³Z´ and ³ C´ section
Secondary members are ³I´ or ³C´ section which are heavy in weight.
Delivery ± ± average 6 to 8 weeks
Delivery- average 20 to Delivery26 weeks
oundation -simple Foundation-
design, easy to construct & light wt.
oundationFoundation-
expensive, heavy foundation required.
Erection cost and timetime accurately known
Erection cost and timetime 20% more than PEB
Overall price - Higher price per square meter.
Overall price -30%lower
Architecture-achieved at Architecturelow cost
Erection process is easy, fast, step by step
Architecture- achieved at Architecturehigher cost
Erection process is slow and extensive field labor is required.
PRE ENGINEERED BUILDING vs CONCRETE BUILDINGS
APPLICATIONS
Industrial Buildings Warehouses Commercial Complexes Showrooms Offices Schools Indoor Stadiums Outdoor Stadiums with canopies Gas Stations Metro Stations, Bus Terminals, Parking Lots Primary Health Centers, Angan wadi¶s And many more«
Industrial
Building
Parking lots
Indoor
Railway
Stadiums
Station
Aircraft Hangars
Wear house
Metro Station
High rise Building
ADVANTAGES
Aesthetic Appeal Faster Completion Economical Seismic Resistance Ease of Expansion Maintenance Free Large Clear Spans Controlled Quality
CONCLUSION
PEB concept has been very successful and well established in North America, Australia and is presently expanding in U.K and European countries. PEB construction is 30 to 40% faster than masonary construction. PEB buildings provide good insulation effect and would be highly suitable for a tropical country like India. The
pre-engineered building calls for very fast construction of buildings and with good aesthetic looks and quality construction. Pre-engineered Buildings can be used extensively for construction of industrial and residential buildings.
REFERENCES
KIRBY Building System KUWAI T. KAR THIK FABRICATORS India P Ltd. MULTCOLOR PROJECTS India Ltd. LLOYD INSULATIONS India Ltd MABANI STEEL LLC, U.A.E STRUCTURAL ENGINEERING at WSP Asia Limited Philippines ZAMIL STEEL Building India Pvt.Ltd