Pre Engineered Building

CHAPTER 1 INTRODUCTION

1.1 GENERAL

Buildings & houses are one of the oldest construction activities of human beings the construction technology has the beginning from primitive construction technology to the present concept of modern house building. The present construction methodology for buildings calls for the best aesthetic look, high quality & fast construction, cost effective & innovative touch. 1.2 PEB IN INDIA

India has the second fastest growing economy in the world and a lot of it, is attributed to its construction industry which figures just next to agriculture in its economic contribution to the nation. In its steadfast development, the construction industry has discovered, invented and developed a number of technologies, systems and products, one of them being the concept of Pre-engineered Buildings (PEB s). As opposed to being on-site fabricated, PEB s are delivered as a complete finished product to the site from a single supplier with a basic structural steel framework with attached factory finished cladding and roofing components. The structure is erected on the site by bolting the various building components together as per specifications. PEB s are developed using potential design software. The onset of technological advancement enabling 3d modelling and detailing of the proposed structure and coordination has revolutionized Conventional building construction. Pre-Engineered

PEB has boon to Multi storey Buildings in India. Decking sheets with concrete over can be used as roofing and raised to any extent extent above 40 meters. meters. These have a tracking rate of 80% in western western countries. PEB Buildings is the future future for India. Most of the Indian Indian 1

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business community is just started to realize realize the benefits of PEB .Where you have been building with w ith concrete for as long as anyone can remember, it is difficult to change. However India’s most progressive companies are seeing the benefits of PEB

Although PEB systems are extensively used in industrial and many other non – residential constructions worldwide it is relatively a new concept in India .these concept were introduced to the Indian markets lately in the late 1990’s with the opening up of

the economy and a number of multi nationals setting up their projects .the market potential of PEB is 1.2 million million tonnes per annum .the current pre – engineered engineered steel building manufacturing capacity is 0.35 tonnes to nnes per annum. annu m. The industry is growing at the compound rate of 25 to 35 % [16]

1.3 SCOPE AND OBJECTIVES OF THE PROJECT 1.3.1 SCOPE OF THE PROJECT

1. Steel buildings in which excess steel is avoided by tapering the sections which in turn is more economical and aesthetic than conventional c onventional steel building 2. Tapering is done as per Bending Moment requirements as to avoid excess of steel. 3. Components are manufactured in factory and assembled on site. 4. Larger plate dimensions are used in areas of higher load effects in case of large spans and high rise industrial building such as aircraft hangars, warehouse etc. 5. An efficiently designed Pre-Engineered Building can be lighter that the conventional steel buildings by up to 30% and thus t hus economical



























40% faster than masonry 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 and quality quality construction.

Pre-engineered Buildings Buildings can be used used

extensively for construction of industrial and residential buildings. 1.3.2 OBJECTIVE OF THE PROJECT

The following are objective of the project and a detailed report on design and analysis of the pre-engineered building is discussed in the upcoming chapters. 1. To Study Pre-Engineered Building. 2. To Prepare a Model of P.E.B. 3. To Analyze Structure Using STAAD Pro. 4. To Design Sections, Connections etc. 5. To Study The Effect Of P.E.B. For Following Issues: i. To Reduce Complexity On Site. ii. To Achieve Accuracy. iii. iii. Speed of Work.



























CHAPTER 2 LITERATURE REVIEW

2.1 GENERAL

In this chapter the literature review of pre-engineered building is carried out from various books, reference, journals, and from several websites .the brief discussion of the pre-engineered building is presented prese nted below in this project 2.1.1 Syed Firoz, Sarath,Chandra Kumar et.al (2012) observed that, The pre-

engineered steel building system construction has great advantages ad vantages to the single storey buildings, practical and efficient alternative to conventional buildings, the System representing one central model within multiple disciplines. Pre- engineered building creates and maintains in real time multidimensional, data rich views through a project support is currently being implemented by STAAD pro software packages for design and engineering [16]. Choosing steel to design a Pre-engineered steel structures building is to choose a material which offers low cost, strength, durability, design flexibility, adaptability and recyclability. Steel is the basic material that is used in the Materials that are used for Pre- engineered steel building. It negates from regional sources. It also means choosing choosing reliable industrial products which which come in a huge huge range of shapes and colours; it means rapid site installation and less energy consumption. It means choosing to commit to the principles princ iples of sustainability. Infinitely recyclable, steel is the material that reflects the imperatives i mperatives of sustainable development.

A tall steel building is not more in the total number of tall ta ll steel structures that are built around the world. A large steel structures being built are only single storey buildings for industrial purpose. Secondary structural members span the distance between the



























frames. Secondary structural, as these members are sometimes called, may serve as flange bracing for primary framing and may function as a part of the building’s lateral

load – resisting resisting system. Roof secondary members, known as purlins, often form an essential part of horizontal roof diaphragms; wall secondary members, known as girts, are frequently found in wall bracing assemblies. The majority of steel structures being built are only low-rise buildings, which are generally of one storey only. Industrial buildings, a sub- set of low-rise buildings are normally used for steel plants, plants, automobile automobile industries, light, utility and process industries, thermal power stations, warehouses, assembly plants, storage, garages, small scale industries, etc. These buildings require large column free areas. Hence interior columns, walls and partitions are often eliminated or kept to a minimum. Most of these buildings may require adequate headroom for use of an overhead traveling crane. A third type of secondary framing,[16]] known by the names of eave strut, eave purlin, or eave girt, acts as part — its purlin and part girt — its top flange supports roof panels, its web, wall siding. Girts,

purlins, and eave struts exhibit similar structural behaviour. Since most secondary members normally encountered in metal building systems are made of cold- formed steel, our discussion starts with some relevant issues in design of cold-formed steel structures.

2.1.2 Aijaz Ahmad Zende 1, Prof. A. V. Kulkarni, et.al (Jan. - Feb. 2013) observes

that even though PEB

structures provides clear span, it weighs lesser lesser than that of

Conventional Buildings. Infinitely recyclable, steel is the material that reflects the imperatives of sustainable development. For longer span structures, Conventional buildings are not not suitable suitable with clear spans. Pre-engineered building building are the best solution solution for longer span structures without any interior column in between as seen in this present work, an industrial structure has been designed for 88m. With the advent of



























up to 90.0 meters with eave heights up to 30.0 meters. PEB structures are found to be costly as compared to Conventional structures in case of smaller span structures. To Conclude ―Pre -Engineered Building Construction gives the end users a much more

economical and better solution for long span structures where large column free areas are needed [6].

2.1.3 C. M. Meera (June 2013) observes that Pre-Engineered Building (PEB) concept

is a new conception of single storey s torey industrial building construction. This methodology is versatile not only due to its quality pre-designing and prefabrication, but also due to its light weight and economical construction. The concept includes the technique of providing the best possible section according to the optimum optimum requirement. requirement. This This concept has many advantages over the Conventional Steel Building (CSB) concept co ncept of buildings with roof truss. This paper is a comparative study of PEB concept and CSB concept. Pre-Engineered Building concept have wide applications including warehouses, factories, offices, workshops, gas stations, showrooms, vehicle parking sheds, aircraft hangars, metro stations, schools, recreational buildings, indoor stadium roofs, outdoor stadium canopies, railway platform shelters, bridges, auditoriums, etc, explicitly as in. PEB structures can also be designed as re-locatable re -locatable structures. Steel is a material which has high strength per unit mass. Hence it is used in construction of structures with large column-free space. Most of the Industrial Structures require this criterion. cr iterion. An Industrial Warehouse is a storage building and is usually characterized as single storey steel structures with or without mezzanine floors. The enclosures of o f these structures may be brick masonry, concrete walls or GI sheet coverings. The walls are generally non bearing but sufficiently strong enough to withstand lateral forces caused by wind or earthquake. The designing of industrial warehouse includes designing of the structural elements including principal rafter or roof truss, column and column base, purlins, sag





























Buildings (PEB) and Conventional Steel Buildings (CSB), according to the design concepts. The paper starts with the discussion of methods adopted in the study. Introduction to PEB systems and CSB systems are then described followed by the details of case study. Loads and the load combinations adopted for carrying out the analysis of the structure is well defined in the further portions. A section depicting the importance of the software used and the software procedure followed fo llowed is included. Final portion explains the results res ults obtained from the software analysis of o f the t he case study and the inferences from the literature studies. The paper aims at developing a perception of The design concepts of PEB structures and its advantages over CSB structures.

2.1.4 Jatin D. Thaka r, 2 Prof. P.G. Patel observes that Pre-engineered building are

steel building wherein the framing members and a nd other components are fully fabricated in the factory after designing and brought to the site for assembly, mainly by nut-bolts, thereby resulting into into a steel structure of high quality quality and precision. In conventional steel construction, we have site welding involved, which is not the case in P.E.B using nut-bolt mechanism. These structures use hot rolled tapered sections for primary framing and cold rolled sections for secondary framing as per the i nternal stress requirements, thus reducing wastage of steel and the self- weight of the structure and hence lighter foundations. foundations. International codes are referred in their their design as per the MBMA (Metal Building Manufacture Association) Standards which are more flexible Allowing the use of built - up sections of minimum 3.5 mm thickness against 6 mm as



























2.1.5 G. Sai Kiran, A. Kailasa Rao, R. Pradeep Kumar (Aug 2014) observes that, in

recent years, the introduction of Pre Engineered Building (PEB) concept in the design of structures has helped in optimizing design. The adoptability of PEB in the place of Conventional Steel Building (CSB) design concept resulted in many advantages, including economy and easier fabrication. In this study, an industrial structure (Ware House) is analysed and designed according to the Indian standards, IS 8001984, IS 8002007 and also by referring MBMA-96 and AISC-89. In this study, a structure with length 187m,width 40m,with clear height 8m and having Slope 1:10,isconsidered to carry out analysis& design for 2D frames (End frame, frame without crane and frame with 3 module cranes). The economy of the structure is discussed d iscussed in terms of its weight comparison, between Indian codes (IS800-1984, IS800-2007) & American code (MBMA-96), & between Indian codes (IS800-1984, IS800-2007).

2.1.6 S.D. Charkha and Latesh S (June 2014) observes that, Using of PEB instead of

CSB may be reducing the steel quantity. Reduction in the steel quantity definitely reducing the dead load. Reduction in the dead load reducing the size of Foundation. Using of PEB increase the t he Aesthetic view of structure.

2.1.7 U. D. Dabhade1, N.A.Hedaoo2, Dr. L. M. Gupta3 and Dr. G. N (2009)

observes that, the time savings of 55.3% is achieved due to use of steel framed composite floor construction rather than precast framed fra med with precast concrete floor and



























concrete floor, which required extra 22.70% of direct cost and 14.96% of net cost. However, study is restricted to structural frame only. If other items are also considered in the study like excavation work, finishing items, services, cladding etc.

2.2 CLASSIFICATION CLASSIFICATION OF BUILDINGS B UILDINGS A healthy trend in the form of growth in demand for construction works in residential, Commercial, Institutional, industrial and infrastructure sectors are being seen over the past decade. Modern Modern Structures Structures are much much more complex complex and sophisticated sophisticated as compared compared to earlier period. One of the major changes which are being felt by all is that the present structures are taller and thinner. Modern day requirement of structures is that these should be lighter yet not compromising on functionality. functionality. Civil engineering construction has seen a continual economic competition between steel, concrete and other construction materials.

2.2.1 Rei Rei nf orce or ced d Cement Cement Concre Concr ete B ui l dings di ngs Reinforced concrete is concrete in which reinforcing bars have been integrated to improve one or more properties of the concrete. For many years, it has bee n utilized as an economical construction material in one form or another. A large part of its worldwide appeal is that the basic constituent materials cement, sand, aggregate, water, and reinforcing bars are widely available and that it is possible to construct a structure using local sources of labour and materials.



























2.2.3 Stee teel Bu il dings Steel is the material of choice for design because beca use it is inherently ductile and flexible. It flexes under extreme loads rather than crushing and crumbling. Structural steel s low cost, strength, durability, design flexibility, adaptability and recyclability continue to make it the material of choice in building construction. Today s structural steel framing is bringing grace, art and function together in almost limitless limitless ways and is offering new solutions and opportunities to create challenging structures, which were once thought impossible. Steel structures have reserve strength. Simple stick design in the steel framings allows construction to proceed rapidly from the start of erection.

2.2.4 Conventi Conventi onal Stee Steel Bu i ldi ngs Conventional Steel buildings are consultant and conservative. The Structural members are hot rolled and are used in conventional buildings. The materials are produced or manufactured in the plant and are shifted to the site. The raw materials are processed in the site for the desired form and erected. The modifications can be done during erection by cut and weld process. process . Truss systems are used in conventional system.

2.2.5 Pre Pr e-engi -engi neer neer ed Ste Stee el Bu i l din gs Pre-engineered Steel Buildings are manufactured or Produced in the plant itself. The manufacturing of structural members is done on customer requirements. The detailed



























elastic properties of the members. Based on this, the data is stored and member section properties are computed. •

Allowable stress design method is used as per the AISC specifications.

•

Unless otherwise specified, the deflections will go to MBMA, AISC criteria and standard industry practices.

•

In Primary Framing Moment resisting frames with pinned or fixed bases.

•

Using IS 875 875 Part 3 design wind loads loads are calculated calculated and Using IS 1893- 2002 seismic loadings are calculated.

•

In Secondary Framing Cold formed Z sections or C sections for purlins or girts designed as continuous beams spanning over rafters and columns with laps.





























2.2.6 Pre Pr e-engi -engi nee neer ed B ui l dings di ngs vs. vs. conventi conventi onal bui l dings di ngs [16] [16] Property

Pre-engineered

Steel Conventional Conventional Steel buildings

buildings Structural weight



Pre-engineered



Primary steel members are

buildings are on the

selected hot rolled t sections.

average 30% lighter

Which are, in many segments

because of the efficient

of the members heavier than

use of steel. Primary

what is actually required by

framing members are

design?

tapered

constant

cross

section

section. With the large

regardless

of

varying

depths

magnitude of the local stresses

built

in

higher stress.

areas

up

of

Members

the

have

along the member length.



























significantly reduced. Basic

substantial engineering and detailing

design based on international work is required from the very basic design codes are used over is required by the consultant with and over.

fewer design aids.

Specialized

computer

analysis

programs

design

optimize material required. Drafting is also computerized using

standard

details

to

minimize the use of project custom details.

Delivery

Average 6 to 8 weeks

Foundation

Simple

design,

easy

construct and light weight.

Average 20 to 26 weeks to Extensive, required.

heavy

foundation



























experience

with

similar erection costs and time are not

buildings.

estimated accurately.

The erection process is faster and much easier with very less

requirement

Erection

process

is

slow

and

extensive field labour is required.

for Heavy equipment is also needed.

equipment.

The

Seismic

low

weight

flexible Rigid heavy frames do not perform

frames offer higher resistance well in seismic zones. to seismic forces.

Resistance Over

Price per square meter may be Higher price per square meter.

All Price

as



























Cost of Charge order

PEB manufactures usually Substitution of hot rolled sections stock a large amount of that infrequently

rolled

by

mills

is

can be flexibly used in many expensive and time consuming. cons uming. types of PEB projects.

Building Accessories

Designed to fit the system Every project requires different and with standardized and inter special design accessories and special changeable parts. Including sourcing for each item. Flashing and pre designed flashing and trims must be uniquely designed and trims. Building accessories fabricated. are

mass

produced

for

economy and are available with the building.

Future

Future expansion is very easy Future expansion is most tedious and



























Performance

specially to act together as a job. Design and detailing errors are system

for

maximum possible when assembling the the diverse diverse

efficiency, precise fir and components into unique buildings. peak performance performance in the field. field.

2.3 PRE-ENGINEERED BUILDINGS or (PEB) 2.3.1. General India being a developed country massive house building construction is taking place in various parts of the country.[10] Since 30% of Indian population lives in towns and cities; hence construction is more in the urban places. The requirement of housing is tremendous but there will always be a shortage of house availability as the present





























formed Z and C-shaped members may be used as secondary structural elements to fasten and support the external cladding. Roll-formed profiled steel sheet, wood, tensioned fabric, precast concrete, masonry block, glass curtain wall or other materials may be used for the external cladding of the building. building. In order to accurately design a pre-engineered building, engineers consider the clear span between bearing points, bay spacing, roof slope, live loads, dead loads, collateral loads, wind uplift, deflection criteria, internal crane system and maximum practical size and weight of fabricated members. Historically, pre-engineered building manufacturers have developed pre-calculated tables for different structural elements in order to allow designers to select the most efficient I beams size for their projects.



























with a choice of single skin s kin sheeting with added insulation or insulated sandwich panels for roofing and wall cladding. The concept is designed des igned to provide a complete building envelope system which is air tight, energy efficient, optimum in weight and cost and, above all, designed to fit user requirement like a well fitted glove. [6]

Pre-engineered steel buildings can be fitted with different structural accessories including mezzanine floors, canopies, fascias, interior partitions etc. and the building is made water proof by use of special mastic beads, filler strips and trims. This is very versatile buildings systems and can be finished internally to serve any functions and accessorized externally to achieve attractive and unique designing styles. It is very advantageous over the conventional buildings and is really helpful in the low rise



























ready for the site bolting. In India I ndia the use of PEB will reduce total construction time of the project by at least 50%. This also allows faster occupancy and earlier realization of revenue. Lower Cost: Due to the systems approach, there is a significant saving in design,

manufacturing and on site erection cost. The secondary members and cladding nest together reducing transportation cost. Flexibility of Expansion: Buildings can be easily expanded in length by adding

additional bays. Also expansion in width and height is possible by pre designing for future e xpansion. Larger Spans: Buildings can be supplied to around 80M clear spans.



























right at the drawing preparation stage. Systems engineering and fabrication methods help reduce interim financing costs through faster construction and minimized field erection expense. An added benefit is earlier occupancy of o f the facility and a head start on day-to-day operations by the client. Apart from costs, there is an assurance of factory-built quality and uniformity in design and fabrication. These systems are also energy ener gy efficient; incorporate watertight roofing systems; enable easy disassembly or future expansion and have the lowest life cycle maintenance costs. Adding to these; there is no mess of sand and cement; power savings; walkable ceilings; progressive and non-progressive panel systems s ystems for walls. A poor man can be provided with a home created under strict quality quality control control and having a longer life span,



























•

Erection of the building is fast.

•

The building can be dismantled and relocated easily. ea sily.

•

Future extensions can be easily eas ily accommodated without much hassle.

•

Increased Life cycle performance and a nd cost competitiveness

•

Environment friendly structures

•

Better rainwater harvesting through gutters and down-take arrangements

•

Lighter weight; savings in foundation cost of 10 -20 percent

•

The building can be dismantled d ismantled and relocated easily





























in any type of geographic location like extreme cold hilly areas, high rain prone areas, plain land, extreme extreme hot climatic zones etc. Applications of Pre-engineered steel buildings include •

Houses & Living Shelters

•

Factories



























compatible to modern demands viz. speed, quality and value for money. Preengineered buildings find many pre-engineered construction applications, which could be intrinsic and high-end.

PEB prospect in the world:

Technological improvement over the year has contributed immensely to the



























FUTURE OF PEB

The steel structures (SS) market in India is in excess of 4.5 Mn.MT, growing at a rapid pace of more than 10% p.a. over the past few years. This market has experienced a higher growth compared to both Indian steel industry as well as Indian construction GDP. Overall construction sector accounts for majority (greater than 80%) of the steel



























2.4.2 MANUFACTURING MANUFACTURING OR PROCESSING PROCESSING Manufacturing is done through the raw material which is imported from steel production companies. The imported steel is in the form of rolled sheets. s heets. For the hot rolled and cold formed sheets cutting is done to desired dimensions and welded with submerged arc welding.



























6. Cutting and threading sag rods and bracing rods 7. Fabrication of Diagonal bracing angles or pipes 8. Profiling the Galvalume / Zincvalume sheets for roo fing and wall cladding 9. Manufacturing Gutters, down take pipes in press bend 10. Procuring and assigning required matching fasteners for connections co nnections





























erection. They shall be pre punched at the factory to provide for field bolting to the



























for embedding into the soil. The dimensions for Anchor bolts are taken from support



























shipping, transportation, unloading and on-site storage does not take into account the



























C. Construct the foundation using the materials materials recommended as per design parameters.



























for drying. Puddles of water should not be allowed to collect and remain on columns























































































































































































































































































































































































































































































































































































































4.2.1 DESIGN PROCESS AND PRINCIPLES Loads on Structure The determination of the loads acting on a structure s tructure is a complex problem. The nature of the loads varies essentially with the architectural design, the materials, and the location of the structure. Loading conditions on the same structure may change from time to time, or may change rapidly with time.

D ead load:

Dead loads shall cover unit weight/mass of materials, and parts or components in a building that t hat apply app ly to the determination of o f the dead loads in the design of buildings and shall be considered as per IS: 875 (Part 1) - 1987 according to the densities of the possible components. co mponents. This includes main frames, purlins, girt, cladding, bracing brac ing and a nd connections etc. L ive L oad: oad:

Imposed loads shall be considered as per IS: 875 (Part 2) 1987. Live load shall be considered as 2.675 KN/m for the analysis and design. Win d L oad: oad:

The basic wind speed and design des ign velocity which shall be modified shall be taken As per IS: 875 (Part 3) 1987. As though this warehouse building is located within the area surrounded by high rise apartments and buildings action of wind load is neglected as even the eave height is limited only to 6m wind load is not considered. co nsidered.



























4.2.2 DESIGN CODES

Following are the main design codes generally used: AISC: American institute of steel construction manual AISI: American iron and steel stee l 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 (IS1893-2002 PART 1 FOR EQ) and (IS 875 PARTIII FOR

WIND)

4.3 DIMENSIONS OF THE T HE WAREHOUSE

Width

= 60 meters

Length

= 15 Meters

Eave Height

= 6 Meters

Bay Spacing

= 6 Meters

Brick work

= 2 Meters

Rise

= 2m

Slope

= 14.93 degree





















































Fig. 4.2 ELEVATION OF THE BUILDING B UILDING

Fig. 4.3.3 SIDE WALL ELEVATION OF THE BUILDING B UILDING



























4.4 DIMENSION OF ROOF Area

= 15 m 60 m 

Span

(l) = 15m

Rise

(h) = 2m

Slope of the roof

  =

tan-1 ( 2 ) = 14.930 7.5

= 14.930



Thus inclination of roof with horizontal  = 14.930

4.4.1 Length of the rafter: (l r) Lr = =

(height of the column) 2 + (rise) 2

Lr = =

(6 )2 + (2)2

Lr = = 7.76m 7.76 m

Actual length of the sheeting is likely more than this to cover eave girder

4.4.2 Number of purlins Maximum allowable purlin spacing = 1400mm Approximate number of purlin

=

7762 1400

= 5.54 no’s Place 6 number of purlin on each rafter @ 1290mm c/c Spacing of purlins = 1.29 m





























4.4.3 Loading calculation 4.4.4 Dead load: Roofing material – GI GI sheeting with unit weight of 150 N/m 2 Assuming unit weight of purlin as 100 N/m 2 Total dead load

= 150 + 100 = 250 N/m2 = 0.250 KN/m2

Dead load on plan area = load bay spacing 

= 0.25 6 

= 1.5 KN/m

4.4.5 Live load:

As per IS 875 part 2 when slope is greater than or equal to 10 (i.e.)

  10

then the

imposed load on the purlin is 750 N/m 2 for every degree increase in slope in excess of 10 degree but not less than 400 N/m2 Live load

= 750 -20



[14.93-10] = 651 N/m2

= 651 N/m2 2 3

rd.

Load =

2 3



651 KN/m2

= 434.2 KN/m2





















































4.5 DESIGN OF PURLINS Span

= 14 m

Length of the continuous purlin = 6 m Spacing of purlin

= 1290 mm

Slope of the roof



= 14.93

The purlin is subjected to biaxial bending moment and as to design for different load combinations and here as we exclude wind load only under live load and dead load combination is designed The following are the loads; Wd = 1 KN WL = 1.62 KN And the components along the principal axes of the purlin are:

4.5.1 Dead load Wdy = Wd cos = 1 cos (14.93) 

= 0.966 KN Wdy = Wd sin



= 0.2574 KN

4.5.2 Live load Wly = Wl cos = 1.l2 cos (14.93)



























4.5.3 Load Case: D.L + L.L Mx1 = [ W

DY

B

10

=

[

0.966 10

+ W LY B ] 9



1.566 9

] 6

= (0.9066 + 0.174) 6 

Mx1 = 1.6236 KNm My1 = [ WlY B + WlxB ] 10

9

= [ 0.966  0.414 ]  6 10

9

= (0.9066 + 0.046) 6 

My1 = 0.8576 KNm

With these bending moment values on trying ISMC 75

Whose properties are

Zx = 20.3cm3, Zy = 4.7 cm3  

 

Here

MX 1 MY 1 Zx

1.62 20.3





Zy

0.85 4.7

KN/m2

 = 180.85 N/m2

Here the stress is greater than the permissible stress



























 

1.62 103.9



Here  = 110.23

0.85 9

KN/mm2

160 N/mm2

Thus the value is lesser than the permissible value 160 n/mm 2

Hence it is safe. Thus provide 6 no’s of ISMC 150 at 1.29m c/c





























4.6 DESIGN OF STEEL RAFTER 4.6.1 Total load Dead load from sheeting = 150 N/m 2 Self-weight of purlin

= 100 N/m2

Total dead load

= 250 N/m2

Spacing of purlins

= 1.29 m

Dead load on each purlin = 0.250 1.29 

Total dead load

= 0.3225 KN/m

Factored dead load

= 1.5 0.3225 = 0.4837 KN/m

Live load

= 2.6052 KN/m

Factored live load

= 1.5 0.26052 = 3.9078 KN/m

Total working load

= 1.5 6 = 9 KN/m

Total factored load

= 1.5 9 = 13.5 KN/m









LENGTH OF RAFTER (L) =7.76 m Design moment

M=

Wl 2 8



























4.6.2 Properties of the section:

Depth of the section sectio n

h = 400 mm

Width of the flange

b = 140mm

Section area

a = 7845.58mm2

Thickness of the flange

tf = 16mm

Thickness of the web

tw = 8.9 mm

Depth of web

d = h-2 (h/2) = 400 – 2 2 (32.8) = 333.4 mm

Moment of inertia about Z – Z Z axis IZZ = 20438.4 10 4 mm4 

Elastic section modulus Ze = 1022.7 10 3 mm4 

Outstanding leg of compression flange B = 140 /2 = 70



























V D

f y



3

V D

3



h  T W



400  8.9

1 1.1

250



area

1.1

f y



3

V D

1



1 1.1

V D



467728N

V D



467.128

27.37

Hence It Is Safe

4.6.5 Check for Moment Capacity

D/TW = 38.2 WHICH IS LESS THAN 67 , SINCE =1 

Hence, f y 1



area





























4.6.6 Check for deflection 4

 

 

5  wl

384  EI 5 17.3 7.3(8300 300)

4 4

2 105  20458.4  10

  27.127mm

Permissible deflection for a beam bea m in building = Le/300 = 8300 / 300 = 27.67 mm Hence the deflection is within the permissible per missible limits

Hence it is Safe Provide ISMB 400 TOTAL WORKING LOAD = L.L + D.L = 12.8 4.5 

= 17.3 N/mm



























4.7 Design of Column 4.7.1 Design stress C olumn  6 m Load = factored load + factored live load + self weight of the beam = 0.4837 + 3.96 + 0.604 = 4.9877



6

= 29.92 KN fcd  125

N mm 2

Use ISMB 400 @ 604.3

N m

= 7846 mm 2 . Width of the Flange = 140 mm

Area P rovided

Selecting 20 mm Plates , breadth required ' b ' is obtained from 2b ×t = 7846 7846





























For ISMB 400 @ 604.3 4 Izz = 2045.4 × 10 mm Iyy = 15846 mm

N m 4

2

For the section selected Izz = Izz + 2bt (

d 2

+

t 2 ) 2

4 2 Izz = 301.38 301.384 4 × 10 10 + 2 × 200 × 20 (100 + 10 ) 6 4 Izz = 301.384 × 10 mm



















































































































































































































CHAPTER 5 ANALYSIS USING STAAD PRO





































































































































CHAPTER 6



























7. Beam to column connection : [4.10]



















































Pre Engineered Building

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