Structural layout

8/18/2019 Structural layout

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Contents

Structural Layout........................................................................................... 2

Introduction...............................................................................................2

1.0 Concept/Preliminary design of Buildings............................................2

1.2 Choice of Structural Form...................................................................3

1. Floor systems.......................................................................................5

1.! Preliminary si"e of structural mem#er ...............................................7

1.$ Structural principles........................................................................7

1.% &ertical #racing systems...............................................................10

1.' Bracings systems.........................................................................15

2.0 Structural Layout of Pipe (ac)s.........................................................16

.0 Structural Layout of *an) farm...............................................................29

+esign Considerations for *an)farm Layout,.................................................31

Plot Plan -rrangement for *an)farm............................................................32

+y)e nclosure........................................................................................33


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Structural Layout

Introduction

1.0 Concept/Preliminary design of Buildings

+ecisions ta)en at concept/Preliminary design stage ill influence the etent to hich theactual structure approimates to the ideal #ut so ill decisions ta)en at detailed designstage.

a. Safety.*he ideal structure must not collapse in use. It must #e capa#le of carrying the loadingreuired of it ith the appropriate factor of safety. *his is more significant at detaileddesign stage as generally any sort of preliminary design can #e made safe. Pay particular

attention to fire reuirements hoe3er.#. Ser3icea#ility.

*he ideal structure must not suffer from local deterioration/failure from ecessi3edeflection or 3i#ration. +etailed design cannot correct faults induced #y #ad preliminarydesign.

c. conomy.*he structure must ma)e minimal demands on la#our and capital4 it must cost as little aspossi#le to #uild and maintain. -t preliminary design stage it means choosing the righttypes of material for the ma5or elements of the structure and arranging these in the rightform.

d. -ppearance.*he structure must #e pleasing to loo) at. +ecisions a#out form and materials are made

at preliminary design stage4 the si"es of indi3idual mem#ers are finalised at detaileddesign stage.*hings that are discussed and attended to during the concept design stage,

I. *ype of construction6 reinforced concrete precast concrete reinforced masonrystructural steel cold7formed steel ood etc.

II. Column locations6- uniform grid facilitates repetiti3e mem#er si"es reducing thecost and increasing the speed of construction. Bay dimensions may also #e optimi"ed tominimi"e material uantities hile efficiently accommodating specific space reuirementssuch as par)ing garages and partition layouts.

III. Bracing or shear all locations68ori"ontal forces due to ind earthua)es etc.must #e transferred don from the superstructure to the foundations. *he most efficientmeans of accomplishing this is usually to pro3ide 3ertical #racing or shear alls oriented

in each principle direction hich must #e coordinated ith functional and aestheticreuirements for partitions doors and indos.

I&. Floor and roof penetrations6Special framing is often reuired to accommodatestairs ele3ators mechanical chases ehaust fans and other openings.

&. Floor7to7floor heights6-deuate space must #e pro3ided for not only the structureitself #ut also raised floors suspended ceilings ductor) piping lights and ca#le runsfor poer communications computer netor)s etc. *his may affect the type of floorsystem 9reinforced concrete #eams 5oists or flat plates4 structural steel #eams or opene# steel 5oists4 cold7formed steel or ood 5oists or trusses: that is selected.

&I. terior cladding6*he #uilding en3elope not only defines the appearance of thefacility #ut also ser3es as the #arrier #eteen the inside and outside orlds. It must #e

a#le to resist ind and other eather effects hile permitting people light and air to passthrough openings such as doors indos and lou3ers.


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&II. uipment and utility arrangements6Large euipment 9air handling unitscondensers chillers #oilers transformers sitchgear etc.: and suspended utilities9ductor) piping light fitures conduits ca#le trays etc.: reuire adeuate support

especially in areas su#5ect to seismic acti3ity that can induce significant hori"ontal forces.&III. ;odifications to eisting #uildings6Changing the type of roof or roofing materialadding ne euipment and remo3ing load7#earing alls are common eamples ofreno3ation measures that reuire structural input.

-ny discrepancy from a#o3e scrutiny should #e #rought to the notice of the -rchitect in an(FI these matters should #e sorted out #efore proceeding ith any design.

*he principal criteria hich influence the choice of structural material are,a. Strength#. +ura#ility 9resistance to corrosion:4c. -rchitectural reuirements4

d. &ersatilitye. Safetyf. Speed of erectiong. ;aintenanceh. Costi. Craneage.

1.2 Choice of Structural Form

rthogonal 8ori"ontals -ccommodation of mo3ement = either #y 5oints or stress design?lo#al load paths are identifiedlement Scale,Proportional si"es

?lo#al actions are alloed for in the element scheme

2. conomic (euirements;aterials,(a cost = can it #e locally sourced@Placement cost = e.g. #loc) layers are epensi3e currently*ransport of fa#ricated elements = special reuirements@Constructa#ilityIs the structure repeata#le as possi#le;inimum num#er of trades on site*ransport/craneage appropriate for the material considered@

. Functional (euirementsBuilding Ser3ice Integration,

pect holes in #eams = allo for it early on


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Flat soffits are #eneficial in hea3ily ser3iced #uildingsClientAs focus,Speculati3e commercial ill reuire clear spans for eample

Landmar) headuarters ill possi#ly mean a dramatic structure -rchitecture,Complement the architecture if possi#le?et in3ol3ed as early as possi#le in the designPlanning,;inimi"e structural depths if reuired+rainage schemes to #e appropriate to site and local drainagen3ironmental considerations

Choice of Form*he span of the structure is the main consideration. For the to usual forms ofconstruction the first of the folloing charts ad3ises hat forms of construction are

appropriate for hat spans for steel and concrete. *he second chart gi3es a comparisonof the eights of structure reuired for 3arious spans and types of construction for single7storey steel #uildings. *hese #uildings tend to #e etremely ell engineeringeconomically.

Consider needs to #e gi3en to the coordination of mechanical electrical plum#ingegress architectural ci3il landscaping @re7protection security and more. ou need toaccount for others disciplines reuirements of your structure coordination areaAs are,plum#ing and process piping engineering disciplines including #ut not limited to 3ariousater aste and drainage systems process and fuel gasses medical gasses 3acuumser3ices special process fluids as ell as associated fitures euipment controls andappurtenances. Ser3ice cores should #e of a si"e sufficient si"e and in 3ertical alignment.

amples are

Beam penetrations are pro3ided for duct or) and piping4

sla# edges are designed and detailed to accept the fascia4

Floor openings are coordinated ith the stairs and ele3ators4

>penings are pro3ided for mechanical shafts4 and Floor to Foor height is de3eloped

considering #uilding usage utility and ceiling reuirements. (oof geometry must suite the pro5ected usage of the facility4 considering such

constraints as utilities security piping and suspended loading +epth of roof must accommodate suspended 8&-C units and other process related

euipment.

;aimum shipping depth 3aries #ased on shop location and site location localordinance o3er7the7road clearances truc)ing a3aila#ility shop capacity or si"erestrictions.

;aimum shipping length 3aries #ased on truc)ing a3aila#ility local ordinance shop

crane capacity shop si"e restrictions site lay don area installation crane capacity andhandling and lateral sta#ility reuirements.

;aimum eight of shipping piece 3aries #ased on truc)ing a3aila#ility local

ordinance shop crane capacity and installation crane capacity. Bracing geometry should suite the usage of the facility considering openings and

other penetrations and circulation reuirements in the @nal facility. le3ations must #e coordinated ith the final usage of the facility or finished

ele3ation reuirements.


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Shoring reuirements special erection needs design assumptions 3ery helpful

additions to the design documents. *he lateral sta#ility of the structure is a function of the initial design assumptions the

erection seuence and the erector7 installed temporary #racing. (egardless of the natureof the structure the erector is responsi#lefor the lateral sta#ility as it is installed. *he erectorAs temporary#racing must therefore sustain the forces imposed on the structure during theinstallation process.

+esign of concrete framed facilities also reuires a similar under7 standing of the

construction process and coordination. Shoring and re7shoring reuirements.

Loading and support of concrete.

oint location and details in sla#s on grade and alls.

Precast shipping restrictions or truc)ing a3aila#ility.

Cold or hot eather concreting procedures noted ithin the design documents.

Layout of column anchor #olts including the foundation rein7forcing pro3ides the

#asis for accurate initial construction.

1.3 Floor systems

*he principal structural elements of a typical multi7storey #uilding comprise floors #eams andcolumns. - ide 3ariety of alternati3e forms and arrangements can #e used in multi7storey steelframed structures.

*he principal structural elements of a typical multi7storey #uilding

Floor sla#s, Se3eral different types of sla# can #e used in either composite or non composite form.


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- num#er of different floor sla# types can #e used in association ith a steel frame. *he floor sla#usually spans one ay4 it is either simply supported or continuous. ;ost sla# types can #edesigned to act compositely ith the supporting #eams if adeuate shear connection is pro3ided

Composite floors consist of a concrete topping cast onto metal dec)ing.

Composite floor sla#s use metal dec)ing hich spans #eteen secondary steel #eams usuallyspaced at #eteen 2.$ and m centres. Concrete hich may #e either lighteight or normaleight is then poured onto the dec)ing usually #y pumping to ma)e up the composite system.;etal dec)ing acts #oth as permanent formor) for the concrete eliminating the need to pro3ideprops and as tensile reinforcement for the sla#. Steel #ars are included in the sla# to pre3entcrac)ing and to pro3ide reinforcement in the e3ent of degradation of the dec)ing in a fire.

-lternati3e arrangements of primary and secondary #eams can #e adopted for an optimum dec)span of m. -nd a typical system is illustrated.

*here are many types of steel dec)ing a3aila#le #ut perhaps the most commonly used is the re7entrant profile type hich pro3ides a flat soffit and facilitates fiings for ser3ices and ceilings.

Primary and secondary steel #eams

1. Preliminary si!e of structural mem"er

Primary #eams can #e si"ed according to the folloing,

• maimum span D 1$m

• Floor #eam depth D span/20

• (oof #eam depth D span/2$


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Secondary #eams can #e si"ed according to the folloing,

• maimum span D 12m

• Floor #eam depth D span/2$

• (oof #eam depth D span/0

Composite sla#s are typically 12$ to 1$0mm thic) 9o3erall: and can span up to .$m

1.# Structural principles

*he structure must #e designed safely to carry the applied loadings.

*he structure must ha3e adeuate strength and stiffness to resist the applied loads due to gra3ity

and ind. *he function of the structure in resisting 3ertical loads due to gra3ity and hori"ontal loadsdue to ind is generally considered separately.

*he principal floor loadings are due to the self eight of the #uilding and its occupancy. *hese arereferred to as AdeadA and AsuperimposedA 9or AimposedA: loads respecti3ely.

*he floor loadings to #e supported #y the structure ha3e to components,

• *he permanent or dead loading comprising the self7eight of the flooring and the

supporting structure together ith the eight of finishes raised flooring ceiling air7conditioningducts and euipment.

• *he superimposed loading hich is the load that the floor is li)ely to sustain duringits life and ill depend on the use. Superimposed floor loading for 3arious types of #uilding arego3erned #y BS %EE #ut the standard loading for office #uildings reuired #y de3elopers andfunding agencies is usually !)/m2 here mo3a#le partitioning is used.

+ead and superimposed loads in commercial #uildings are often approimately eual.

For normal office loadings dead and superimposed loadings are roughly eual in proportion #uthigher superimposed load alloances ill #e necessary in areas of plant or to accommodatespecial reuirements such as storage or hea3y euipment. *he optimum structural solution is tolocate any hea3ier loadings close to columns or here the floor spans are shorter.

*he design of the floor structure is concerned mainly ith 3ertical loads. *he criteria determiningmem#er si"es depend on floor span.

*he criteria determining the choice of a mem#er si"e in a floor system 3aries ith the span.

In some cases deflection limits may need to #e stricter than those specified in design codes.

In practice floors ill #e designed to limit sagging deflection under the superimposed loadings. *heBritish Standard BS $E$0 go3erning the design of structural steelor) sets a limit on deflectionunder superimposed loading of span/200 generally and span/%0 here there are #rittle finishes.For 3ery long spans this limit is li)ely to #e inadeuate4 for eample the sag alloed #y the codeon a 1$m span girder ould #e !2mm and the designer may consider setting more stringent limits.

dge #eams supporting cladding ill #e su#5ect to restriction on deflection of 1071$mm. +eflectionsmay #e noticea#le in the ceiling layout and should #e ta)en into account hen determining the


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a3aila#le cumulati3e effect of deflections in the indi3idual mem#ers of a floor system although theactual maimum displacement is in practice almost alays less than those predicted #y theoreticalanalysis.

Floor 3i#rations may need to #e controlled.

In some instances 3i#rations of floor components may cause discomfort or affect sensiti3eeuipment and the designer should alays chec) the fundamental freuency of the floor system.*he threshold of percepti#le 3i#rations in #uildings is difficult to define and present limits are ratherar#itrary. *here is some e3idence that modern lighteight floors can #e sensiti3e to dynamic loadshich may ha3e an effect on delicate euipment #ut generally only for 3ery long spans or lightfloors.

Building structures should ha3e sufficient lateral rigidity to resist li)ely ind loads.

Steel #uildings ha3e to #e rigid enough in the hori"ontal direction to resist ind and other lateral

loads. In tall #uildings the means of pro3iding sufficient lateral rigidity forms the dominant designconsideration and de3elopments in this field ha3e led to the construction of taller and taller#uildings such as the ohn 8ancoc) Building or the Sears *oer in Chicago.

;ost multi7storey #uildings are designed on the #asis that ind forces acting on the eternalcladding are transmitted to the floors hich form hori"ontal diaphragms transferring the lateral loadto rigid elements and then to the ground. *hese rigid elements are usually either lattice or rigid 5ointed frames or reinforced concrete shear alls.

Lateral load #earing systems

For most multi7storey #uildings functional reuirements ill determine the column grid hich illdictate spans here the limiting criteria ill #e rigidity rather than strength.

Floor framing systems may #e either simply supported or rigid at the supports. Continuousconstruction is more efficient structurally gi3ing shalloer floors #ut hea3ier columns increasedcompleity at 5unctions and connections ith higher fa#rication costs. In practice the great ma5orityof steel framed multi7storey #uildings use simple construction.


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Floor framing

In addition to strength and stiffness #uilding structures must #e designed to a3oid progressi3e

collapse in the e3ent of a catastrophic accident.

*he partial collapse of a system7#uilt multi7storey #uilding at (onan Point in 1E%G folloing a gaseplosion led to a fundamental reappraisal of the approach to structural sta#ility in #uildings. *hiscentred on the need to limit the etent of any damage in the e3ent of catastrophic or accidentalloadings. *his concept of ro#ustness in #uilding design reuires that any ma5or structural elementmust either #e designed for #last loading or #e capa#le of #eing remo3ed ithout precipitatingprogressi3e collapse of other parts of the structure. *his can #e demonstrated #y consideringalternati3e load paths and structural actions in the damaged state.

In addition there is a reuirement for suita#le ties to #e incorporated in the hori"ontal direction inthe floors and in the 3ertical direction through the columns. *he designer should #e aare of theconseuences of the sudden remo3al of )ey elements of the structure and ensure that such an

e3ent does not lead to the progressi3e collapse of the #uilding or a su#stantial part of it.

1.$ %ertical "racing systems

- 3ariety of structural forms can #e used to pro3ide lateral sta#ility. *he principal systems are shear alls lattice frames and rigid frames #ut more sophisticated systems may #e needed for 3ery tall#uildings.

Shear alls resist ind forces in #ending #y cantile3er action and here they already eist forinstance to pro3ide a fire protected ser3ice core are an efficient method of carrying lateral loads.Lattice frames act as 3ertical steel trusses. (igid 5ointed frames are less effecti3e in pro3idinglateral rigidity #ecause of shear distortion in the 3ertical mem#ers. *he British Standard BS $E$0

sets a limit on lateral deflection of columns as height/00 #ut height/%00 is a more reasona#lefigure for #uildings here the eternal en3elope consists of sensiti3e or #rittle materials such asstone facings.

(igid frames resist lateral loads #y #ending in the #eams columns and connections.

(igid frames resist lateral forces through the stiffness pro3ided #y rigid 5oints #eteen thehori"ontal floor components and 3ertical columns. *he need to resist #ending moments from indloads increases the si"e of the column mem#ers and the compleity of the framing connections.For these reasons rigid frames are only used hen there is a particular functional reason for theiruse such as the need to pro3ide uno#structed interior space ith total adapta#ility.


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>ne possi#le eception to this general rule is the facade frame ith a com#ination of closelyspaced eternal columns and deep spandrel facade #eams. Such a system is usually used for 3erytall #uildings here the facade frame forms a rigid tu#e.

(igid frames resist lateral forces through the stiffness pro3ided #y rigid 5oints

(igid frames a3oid any intrusion #ut are relati3ely epensi3e.

*he ad3antages of the rigid frame are that,

• open #ays #eteen all columns are created

• total internal adapta#ility is pro3ided

8oe3er the disad3antages are that,

• *hey are almost alays more epensi3e than other systems

• Columns are larger than for simple connections.

• ?enerally they are less stiff than other #racing systems ith large comple

connections.

Lattice frames act as 3ertical trusses and a num#er of different forms are commonly used.

Lattice frames act as 3ertical trusses hich support the ind loads #y cantile3er action. *he#racing mem#ers can #e arranged in a 3ariety of forms designed to carry solely tension oralternati3ely tension and compression. Hhen designed to ta)e only tension the #racing is made upof crossed diagonals. +epending on the ind direction one diagonal ill ta)e all the tension hilethe other is assumed to remain inacti3e. *ensile #racing is smaller in cross7section than theeui3alent strut and is usually made up of a #ac)7to7#ac) channel or angle sections. Hhendesigned to resist compression the #racings #ecome struts and the most common arrangement isthe &A #race.


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*ypical cross #racing and


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Shear alls are normally constructed in in7situ reinforced concrete #ut may #e either pre7castconcrete of #ric)or). *hey are more rigid than other forms of #racing and there is a need forfeer of them. Shear cores are shear alls in #o form hich pro3ide torsional or tistingresistance as ell as pro3iding a highly effecti3e #racing system.

Shear alls are effecti3e #ut may create difficulties during construction.

*he ad3antages of shear alling are that,

• concrete alls tend to #e thinner than other #racing systems and hence sa3e space

in congested areas such as ser3ice and lift cores

• they are 3ery rigid and highly effecti3e

• *hey act as fire compartment alls.

*he disad3antages are that,

• they constitute a separate form of construction hich may delay the contract

programme

• it is difficult to pro3ide connections #eteen steel and concrete to transfer the large

forces generated.

For more information on ad3antages/disad3antages of shear alling please clic) here

*he floor structure transfers lateral loads from the faJade to the #racing system.

-ll sta#ility systems use the floor plate as a diaphragm to transfer lateral loads from their point ofapplication to the #racing elements. *he designer should ensure that the floor is capa#le ofperforming this function.

+iaphragm action of floors

Bracing must ensure lateral sta#ility in all directions and also torsional sta#ility.

*he #racing must #e arranged on plan to ensure lateral sta#ility in at least to directions hichshould #e approimately perpendicular 7 typically these correspond to the principal aes of the#uilding. *his ill effecti3ely ensure sta#ility in all directions.

http://www.tatasteelconstruction.com/en/products/walls/modular_wall_systems/http://www.tatasteelconstruction.com/en/products/walls/modular_wall_systems/


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*orsional sta#ility should also #e ensured. *his can #e done #y using an approimately symmetricplan arrangement ideally ith the #racing elements located close to the perimeter of the #uilding.Suita#le location of #racing elements is therefore a fundamental reuirement of the #racing systemdesign.


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1.& Bracings systems

In order to allo any hori"ontal loads hoe3er directed to #e #alanced it is necessary to locate

sufficient num#er 3ertical #racings. *o this purpose the folloing reuirements ha3e to #e satisfied.

a: It has to #e possi#le to consider any floor system as a plane structure restrained #ythe 3ertical #racing system.

#: &ertical #racing systems as eternal restrains of the floor system ha3e to pro3ide asystem of at least three degree of restrains.

c: *he floor systems ha3e to #e a#le to elastically resist the internal forces due to theapplied hori"ontal loads.

In order to fulfill reuirement 9a: diagonal #racings ha3e to #e introduced in the plane of floor thustransforming the floor system itself into an hori"ontal truss. -s an alternati3e the sla# inprefa#ricated concrete elements of the floor system can #e assumed to directly resist the hori"ontalforces as plane plate structure #eing its deforma#ility normally negligi#le.

In case of concrete sla#s the erection of the steel s)eleton reuires particular care #ecause it isuna#le until the floor elements are placed. *emporary #racings are therefore necessary during thispro3isional phase.

In order to fulfill reuirement 9#: the 3ertical steel #racings systems are acti3e in their on planeonly and therefore they represent a simple restraint for the floor system. Hhen reinforcementconcrete #racings are used they can ha3e one to or three degrees of restraint for the floorsystem. Hhen reinforcement concrete #racing are used

+epending upon their resistance to one plane #ending9all: #i7aial #ending or #i7aial #endingand torsion 9core: respecti3ely.


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Finally reuirement 9 C: is fulfilled #y e3aluating internal forces in the floor elements due to themaimum hori"ontal forces that the 3ertical #racing systems are a#le to transit. -lso 3ertical#racing system location has to #e considered.

2.0 Structural 'ayout of Pipe (ac)s

'oads

*he 3arious loads to #e applied to a pipe rac) are the folloing,

7 +ead loads including eight of fireproofing eight of pipes and eight of air coolers

7 Li3e loads due to access platforms

7 *he eight of the liuids in pipes

7 *he thermal loads due to the epansion and/or contraction of the pipes and of the structure

7 &arious loads transmitted #y the pipes and due to operating or accidental conditions 3al3eloadsetc.

7 *he ind loads

7 *he earthua)e loads.

-ll these loads ill #e eamined in a separate chapter as ell as the 3arious load com#inations to#e applied.

*he span idth column main girder longitudinal girder intermediate girder #raced #ay 9orsta#ility #ay: and #racing are defined on the figure here a#o3e. Frame, pipe rac) element includingto columns located in the same trans3ersal plane and the main girders connected to thesecolumns.


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*he pipe rac)s are made either of steelor) or of reinforced concrete or are made of miedstructure steelor) and concrete. *he selection of construction materials ta)es into accountlocation schedule constraints costs and fireproofing specificity of the pro5ect. -s a general ruleunit pipe rac)s are made of steel ith fireproofing ecept hen they support air coolers. In that last

case they are made of concrete. Ktilities and interconnecting pipe rac)s are made of steel. Hhenreinforced concrete is adopted precast construction is preferred. ;ore details on the 3arious typesof structures are gi3en here after as ell as their ad3antages and disad3antages. In addition to thechoice of the material the conceptual design of the structure must ta)e into account theconstruction method that ill #e used.

Structural steel

*his material is the most commonly used. Se3eral alternates may #e met. In most cases all theconnections columns/main girders are restrained 9moment resisting:. *he idth may 3ary from ! to10 meters. *he span is generally limited to 12 meters. *he longitudinal girders are simple steelprofiles4 they are generally hinged at the ends unless restrained ends are more effecti3e to control

deflections 9i.e. for long spans:. Braced #ays are made ith diagonals. *he second alternatecommonly met has a span of 12 to 1G meters. *he difference ith pre3ious alternate is thatlongitudinal girders are made of truss. *his configuration may cause some incon3enient at pipe#ranches since they may lead to remo3e some diagonals to pre3ent from interference ith pipes.*herefore this arrangement shall prefera#ly #e used for road crossing. It may #e used also forinterconnecting pipe rac)s. -nother alternate may consist in the replacement of column fied ends#y the use of diagonals for instance as shon in figure 2 pro3ided that the designer has chec)edthat the piping layout or the plot plan as far as clearance head room and access are concerned.*hese alternates may #e com#ined together.

(einforced concrete

*his material is less commonly used than structural steel. >ne of the main disad3antages of the

reinforced concrete is the site constraint related to cast in place concrete. *he use of prefa#ricatedconcrete elements allos uic) erection. *he main pro#lem remaining ith prefa#ricated elementslays in the design of connections. *he designer ill try to a3oid as much as possi#le momentresisting connections in order to simplify the connection design and to allo a uic)er and easiererection of the pipe rac)s.

Frame

*+o layer pipe rac)

Hhen considering the #ending moments the #est ould #e to ha3e the loer main girderrestrained at ends and the upper one hinged at ends. Sometimes for construction reasons the

re3erse situation is met for more economical in7situ 5oints.

*hree or more layer pipe rac)

*he loest main girder shall #e restrained at ends the upper one too4 intermediate girders may #ehinged at ends.

'ocation of moment connection ,prefa"ricated piperac)s-

If the moment connection is located close to the column the #ending moments are maimum thereinforcement too. Section of mem#ers are freuently congestion ith re#ars so that detailedarrangement shall #e pro3ided to the prefa#ricator on draings as far as use of mechanical #ar

connector 9splices: slee3es grouting counter7plates etc. Casting the connection in7situ may #e


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long and difficult. (elocating the connection close to 2$ M of the idth could minimi"e thereinforcement inside the connection. >n the other hand columns ould #e prefa#ricated ith longappendices at the location of the #eams resulting in more costly formor) difficult handling andlifting.

'ongitudinal girders

*he longitudinal girders shall #e prefera#ly hinged at the ends in order to ha3e easy connections.*his ill lead to design a #raced #ay as in the case of structural steel.

Intermediate girders

Ksually intermediate girders are made of steel.

Braced "ay

*he #raced #ay may consist of concrete frames ith longitudinal girders restrained at the ends. Itmay also consist of hinged longitudinal girders and diagonals 9as for structural steel:. In order tomaimi"e prefa#rication diagonals may #e made of structural steel.

ied structures

-s mentioned a#o3e structures may #e made also of a mi of prefa#ricated concrete elementsand structural steel.

Starting form a concrete structure many possi#ilities are offered to the designer,

7 Kse of steel intermediate girders 93ery common solution:

7 Kse of steel diagonals

7 Kse of steel longitudinal girders

7 Kse of frames ith a loer part made of concrete and the upper made of steel.

*ee post pipe rac)

In case of one layer pipe rac) ith a small idth and small height 3ertical loads ell #alanced andlo hori"ontal loads it ill #e prefera#le to ha3e tee7post pipe rac)s ith one column instead of

to per frame.

2.# *hermal epansion and maimum length

+ue to their length and to the 3ariations of the am#ient temperature pipe rac)s are su#5ect toimportant thermal epansion or contraction. In order to limit the effects of this thermal epansion orcontraction in terms of stresses in the structure epansion 5oints are pro3ided. Pro3ided amaimum distance #eteen to consecuti3e epansion 5oints is complied ith thermal stressesmay #e omitted. *his maimum distance depends on the climatic conditions and on a theoreticalpoint of 3ie on the stiffness of the structure. For concrete pipe rac)s the maimum length#eteen #raced #ay and pipe rac) ends ill generally #e limited to 20 m hen the maimumtemperature 3ariation amplitude is 72$NC/O2$NC or less 1$ m for higher temperature 3ariations.Hhen the #racing #ay is located in the middle of the #ranch the maimum length end to end

should respecti3ely in the range of !0 metres and 0 metres. For steel pipe rac)s these limits are


19/38

higher 0 m for temperature 3ariation amplitude =2$NC/O2$NC and 2$ for higher temperature.Longer pipe rac)s may #e designed and #uilt. *he design ill ta)e into account the thermalstresses de3eloped in these conditions and ill allo either relaation of the stresses #y adeuatemeans 9hinged connections sliding connections: or additional strength #y larger sections 9not

recommended:.

-s a general rule for load analysis of pipe rac) reference shall #e made to the design criteriaspecification. First of all and #efore re3ie of the 3arious loads that may #e applied to a pipe rac)it must #e reminded that some loads must #e ta)en into account locally for the design of a girder.*hey ill not #e ta)en into account in the design of frames columns or #raced #ays unless theyare generated #y special pipe supporting structures such as large transfer lines hich shall #eco3ered #y particular design conditions.

*hese loads are assumed to occur once or tice on the total length of a pipe rac) at a locationhich is not defined. *hey ill ha3e an influence locally #ut not on the o3erall design of the piperac).*hey ill #e clearly identified as such.

ead loads ,'-

+n +eight

-s usual dead loads include the on eight of the structure including platforms ladders andmiscellaneous and including also fireproofing.

Pipes

*he eight of pipes e3en hen empty is included in the pipe loads.

Ca"les

*he eight of the ca#les and of the supporting trays should #e pro3ided #y the lectrical andInstrumentation departments. In a#sence of data an a3erage eight of 1.0 )/m2 for one standardtray may #e ta)en.

ir coolers and other euipment

*he eight of air coolers 9or other euipment: must #e pro3ided #y the euipment manufacturer.*hese data should #e pro3ided ith the detail layout of the supports of the air coolers on the piperac)s.

'i4e loads ,''-

*he li3e loads are those on the platforms or access.

Pipe loads

5ra4ity loads

*hese loads correspond to the eight of the pipes and of the liuid inside. *hree main cases may#e considered, erection operation and test ith corresponding load sym#ols P P> and P*.rection, does not call for particular comments. *he corresponding load may #e considered as theeight of the pipes hen empty during operations. >peration, corresponds to eight of pipes in

use i. e. ith fluid inside 9liuid or gas:. For cold lines the possi#le presence of ice must #e ta)en


20/38

into account if no 9or insufficient: insulation is pro3ided. *est, corresponds to the eight of the pipeshen tested. Ksually they are tested full of ater. In some circumstances for instance for flarelines this may lead to an important o3er design of many #eams and/or columns. In that case thepossi#ility of an air test must #e in3estigated.

Pipes +ith diameter less than or eual to 12 inches ,300 mm-

a. Loads

*he loads of these pipes are usually not pro3ided #y the Piping department. *hey are assumed to#e )non to the Ci3il ngineering department.

*he loads ill depend on the diameter of the lines at the considered layer #ut in order to simplifythe design the folloing loads are considered.

rection condition 9or empty condition: 0.$ )/m2 maimum

>peration condition 2.0 )/m2 minimum

*est condition,

For girders supporting four pipes or less all the pipes shall #e considered as full of ater.

For girders supporting more than four pipes $0M of the pipes shall #e considered as full of aterand chosen in order to produce maimum stresses. >ther pipes shall #e considered as empty.

*he loads shall #e applied on the entire surface occupied #y the pipes including empty spaces.

*he a#o3e loads are 3alid for non insulated pipes. (egarding insulated pipes the eight ofinsulation should #e considered #ut since the spacing #eteen pipes shall #e larger the a#o3eloads are also considered for insulated pipes.

#. Spreading of loads

Small pipes must #e supported at close distances typically metres. Larger lines may #esupported at larger distances. For that reason the spreading of the loads #eteen main girders andintermediate girders is not eual. *he folloing spreading may #e used. *he need for intermediategirders and their spacing must #e gi3en #y the Piping department.

1 M of the load shall #e applied on each intermediate girder the remaining on the main girder.

ample, ith intermediate girders e3ery metres

+istance #eteen main girders % E 12

um#er of intermediate girders 1 2

Load on intermediate girders 1 M 2' M !0 M

Load on main girders G' M ' M %0 M

Pipes +ith diameter larger than 12 inches ,300mm-


21/38

Loads shall #e considered loads at the actual location of the pipe supports. &alues shall #e gi3en#y the Piping department.

6ori!ontal loads ,*'-

*ypes of loads

*he hori"ontal loads either longitudinal or trans3ersal are due to 3arious phenomena.

*he contraction or epansion of pipes ill cause hori"ontal forces longitudinal #ut also trans3ersalsince pipes may ha3e loops tee75unction etc.

Ksually a pipe rac) is designed so that in normal temperature conditions no thermal loads areapplied to the structure. *his means that the length of the pipe rac) is limited to the maimumlength defined in Chapter .

*he thermal loads #rought #y the pipes are due to hot or cold pipes. Pipes at am#ient temperaturedo not #ring thermal loads.

In other ords these loads cannot occur during erection or tests since these operations are madeat am#ient temperature. *hey cannot occur also hen the pipes are empty #ut they may occur ithpipes full ith gas.

*he thermal loads are uasi constant hen the pipe is full and in operation.

*he fluid under pressure in the pipes may also induce hori"ontal loads hich ill #e transmitted tothe pipe rac) through the pipe supports. Hhen the pressure is a normal pressure in operationconditions the loads are uasi permanent.

*he pipe supports are of to types sliding and fied.

Hhen a support is sliding the force it transmits to the pipe rac) cannot #e more than the 3erticalload on the support 9eight of the pipe in operation: times the friction coefficient of the support.

Hhen a support is fied it may transmit any load to the pipe rac). - fied support shall ne3er #e onan intermediate girder.

*he loads transmitted through the pipe supports ill then not #e the same for all girders andframes.

For a gi3en pipe and its support it is not possi#le to add friction loads and anchor loads.

*o other types of hori"ontal pipe loads may occur,

&al3e release loads may ta)e place only at the location of a 3al3e. 8igh 3alues may #e o#tained atthe #eginning of the release then the loads come to lesser 3alues. *hese loads are gi3en #y thePiping department.

3.3.2.2 'oad 4alues

Q &al3e release loads


22/38

-s mentioned a#o3e 3al3e release loads shall #e gi3en #y the Piping department. *hey usuallygi3e only the pea) load. *his pea) load is a dynamic load hich is critical in the design of the girder hich supports directly the 3al3e. For the design of the other components of the pipe rac)scolumns other girders foundations %0 M only of the pea) 3alue shall #e considered. Knless

specified otherise it ill #e considered that only one 3al3e release ta)es place at a time.

Q >ther hori"ontal loads

For pipes of a diameter larger than 12 inches 900 mm: the hori"ontal anchor loads are usuallypro3ided #y the Piping department

*he a#o3e mentioned load are only gi3en for fied supports. For sliding supports the hori"ontalloads cannot #e more than the 3ertical load times the friction coefficient of the pipe

support. If the loads are not a3aila#le #y the time of the pipe rac) design it is recommended toapply the same rules as for pipes smaller than or eual to 12 inches 900 mm:.

For pipes of a diameter smaller than or eual to 12 inches the folloing rules ill apply.

+esign of a pipe supporting girder ill #e done ith a hori"ontal longitudinal force eual to

10 M of the operating eight of the pipes supported #y the girder. *his force has a local effect. Itshall not #e ta)en into consideration for the design of other components frame column #racingfoundation etc. ach main supporting girder shall #e designed in addition to ithstand alongitudinal concentrated load eual to 10 ) and located so as to produce the maimum stresses.*his load shall not #e added to the pre3ious one. *his load is assumed to ha3e only a local effectand shall not #e considered for the design of columns foundations and #racing.

Pipe rac) frames shall #e designed ta)ing into account trans3ersal loads at each layer eual to $ Mof the eight of the pipes at this layer or $ ) hiche3er is the greater. *hese loads shall #e ta)eninto consideration in the design of foundations. For #raced #ays anchor forces transmitted #ylongitudinal girders are an ar#itrary load of $ M of the total pipe load per layer unless pipe stressanalysis dictates a higher 3alue. *he force is supported eually #y the to sides of the pipe rac)9ecept if it is o#3iously rong and if another distri#ution is more adapted:. *he forces shall #edistri#uted to the foundations.

Q Friction coefficients

. If not the folloing 3alues may #e considered.

Surfaces Coefficient

Steel on steel 0.$

*eflon on stainless steel 0.10

*eflon on *eflon 0.10

'ongitudinal girders

Longitudinal girders shall #e calculated as follos,

Q &ertical loads


23/38

?ra3ity loads from intermediate girders

Concentrated 3ertical load of 1$ ) if more unfa3oura#le 9local load:

Q Compression load

1$ M of the 3ertical on the most loaded ad5acent column 9local load:

Q 8ori"ontal load

-n ar#itrary hori"ontal load of '.$ ) located at mid7span 9local load:

ccidental loads 7 Surge loads ,'-

-ccidental hori"ontal 9or 3ertical: pipe loads may occur due to surge in the pipes. *he 3alues are

alays gi3en #y the Piping department. >nly fe lines may #e concerned. *his phenomenon mayin3ol3e se3eral lines at a time. But unless specified otherise it ill #e considered that only oneline is concerned at a time.

Since these loads are accidental they shall #e considered as such in load com#inations and theappropriate load factors ill #e used. >f course surge loads cannot #e com#ined ith ind orearthua)e loads.

*hese loads last a 3ery short time and are transient loads. It means that the energy #rought #y thesurge is dissipated also as mo3ement 9deformations: and heat 9damping: in the structure. *hisdissipation means that surge loads ill #e considered for the girders or elements close to the pipesupports here the load ta)es place. *hey are assumed to #e local loads. Foundations or remoteelements of the structure shall not #e designed to ithstand the surge loads.

3. 8ind loads ,8'-

3..1 *rans4ersal +ind loads

-s a general rule the ind loads are composed of the loads applied #y the ind on,

7 *he structure of the pipe rac)

7 *he pipes

7 *he ca#les

7 *he air coolers.

Pipes

Knless Piping department already pro3ides ind loads from pipes the general formula to #eapplied at each pipe layer is,

F D " R Cf R 9ma O 0.1 R l: R L

Hhere


24/38

F is the hori"ontal ind load for the concerned layer

" is the dynamic ind pressure at the considered le3el

Cf is the force coefficient for pipes

ma is the diameter of the largest pipe at the concerned layer 9minimum 10 inches or 2$0 mm:

l is the pipe rac) idth

L is the length of the eposed area usually this is the pipe rac) span.

*he term D " R Cf must include any gust factor or dynamic factor as reuired #y the applica#lecode.

If not defined in the T+esign Criteria or in the applica#le codes Cf shall #e ta)en as eual to 0.' asa minimum.

Ca"le trays

*he general formula to #e applied at each pipe layer is,

F D " R Cf R 9hma O 0.1 R l: R L

Hhere



Cf is the force coefficient for pipes

hma is the height of the largest ca#le tray at the concerned layer


L is the length of the eposed area usually this is the pipe rac) span.

*he term D " R Cf must include any gust factor or dynamic factor as reuired #y the applica#lecode.

If not defined in the T+esign Criteria or in the applica#le codes Cf shall #e ta)en as eual to 2.0 asa minimum.

ir coolers

*he resulting ind loads on the supports of the air coolers must #e gi3en #y the euipmentmanufacturer.

'ongitudinal +ind loads


25/38

-s a general rule and unless otherise reuired #y pro5ect specifications the ind loads arecomposed of the loads applied #y the ind on,

7 *he structure of the pipe rac)

7 *he pipes

7 the Ca#les

7 *he air coolers.

Pipes and ca"le trays

*he general formula to #e applied at each pipe layer is,

F D " R U R l R L

Hhere




L is the length of the eposed area usually this is the pipe rac) length #eteen to epansion 5oints

U is a coefficient eual to 0.1 for the top layer and 0.0$ for the other layers.

ir coolers

*he resulting ind loads on the supports of the air coolers must #e gi3en #y the euipmentmanufacturer.

Sno+ loads

Ksually sno loads 9or dust and sand loads: are not ta)en into account in the design of pipe rac)s.

9arthua)e loads ,9'-

*he loads due to earthua)e shall #e estimated in accordance ith the corresponding codespecified in the T+esign Criteria.

*he gra3ity loads hich are assumed to #e considered for this estimation are the deal loads andthe pipe loads in operation.

+ue to the lo freuency of 3isits on access platforms of pipe rac)s the corresponding li3e loadsmay #e omitted.

9F'9C*I:S


26/38

Knless noted otherise in the T+esign criteria the alloa#le deflections for pipe rac)s shall #e asfollos.

%ertical deflections

ain girders

*otal deflection in normal operation 9all load cases ecept ind and earthua)e loads: L/!00

Intermediate girders

Com#ined deflection of longitudinal girder and intermediate girder L/200 ith L D span of theintermediate girder D idth of pipe rac).

6ori!ontal deflections ,trans4ersal-

Knder ind loads ithout air7cooler 9or other euipment: 8/1$0 Knder ind loads ith air coolers9or other euipment: 8/200

5;I9 F( S*(;C*;(9 S9'9C*I:

*his selection is not easy to do and no a#solute rule may #e reasona#ly gi3en #ecause of the3arious parameters to #e ta)en into account.

Criteria for selection

*he 3arious criteria to #e retained in the selection of the pipe rac) structure are,

7 *he cost

7 *he construction/erection simplicity and the time schedule

7 *he possi#le ris) of fire and of passi3e fire protection 9fireproofing: in relation ith cost

7 *he local ha#its for pipe rac)s

7 *he location of the pipe rac)

Cost

*he cost direct and indirect is of course the most important criteria ith time schedule for thematerial construction seuence selection.

Ksually steelor) is less costly than reinforced concrete. 8oe3er this may 3ary idely from onecountry to the other.

#.3 Construction/erection


27/38

*he second important criteria ith cost. -ctually #oth criteria are connected to each other in mostpro5ects.

Steelor) could e3en #e uic)er than poured in7place concrete depending upon country hereconstruction site is ith conseuent prefa#rication and transportation time despite of the cycle fordetail design of connections and shop draings.

Hhere prefa#rication of concrete elements may #e made erection can start earlier than forsteelor). rection may #e as uic) as for steelor) #ut ma)ing the connections is longerespecially in the case of moment connections. *his is hy if prefa#ricated concrete is selectedmoment connections shall #e a3oided as much as possi#le or shall #e designed in order to #e easyto #e made.

Passi4e fire protection

Hhere passi3e fire protection has to #e pro3ided this ill ha3e a 3ery minimum influence on

concrete design since the co3er on re#ars can adeuately pro3ide fire protection.

In case of steel structure fireproofing ill need to #e applied. *he corresponding cost and time forapplication may ma)e concrete prefera#le to steelor) hen the etent of fireproofing is large9case of pipe rac)s supporting air coolers:.

'ocal ha"its

Some countries ha3e a strong culture in terms of use of steelor) or concrete. Selection of amaterial hich is not usual for pipe rac)s may lead to pro#lems. For instance use of structuralconcrete in the KS- is not common. *hese pro#lems may affect the design #ut essentially theprefa#rication and erection of the 3arious elements.

'ocation of the pipe rac)

*he location of the pipe rac) is of course in relation ith erection simplicity 9access: and also ithneed for fire protection. But other points may ha3e an influence on the design of the pipe rac)s.Pipe rac)s in process units ill ha3e a large num#er of outgoing and in going pipes. *his is also3alid for interconnecting pipe rac)s close to process units. For interconnecting pipe rac)s far fromprocess units the num#er of going and in going pipes is reduced and use of longitudinal girdersmade of steel truss may #e of some ad3antage.

Soil conditions

Ksually pipe rac) columns are fied 9moment connections: on foundations. *his ill allo smaller#ending moments in the columns and smaller columns so lighter structures. -d3ersely foundations

ill #e larger than ith hinged connections #eteen column and foundation. But glo#ally thissolution is more economical.

In the case of soil conditions implying the use of piled foundations this may ha3e anotherconseuence. Ksually piles cannot ithstand large #ending moments. *o support #endingmoments to 9or more: piles per foundations ill #e needed. In that case the increase of the costof the foundation may #e such that hinged connection are prefera#le.

?enerally this ill not #e the case. ;oreo3er ith the use of trans3ersal tie #eams #eteen

foundations the #ending moments may #e ithstood and the num#er of piles reduced to one perfoundation. Hhere important earthua)es may occur this ill #e the #est solution.


28/38

In case of large idth pipe rac)s and of piled foundations it may #e of some interest to ha3ehinged columns at the #ottom. For foundation design it must #e )ept in mind that for small idthpipe rac)s a common mat per frame supporting #oth columns could #e more economical than tofoundations one per column. *he limit idth cannot #e fied4 it depends on the pro5ect local costs

etc. Ksually it is in the range of ! to % meters.

*


29/38

7 Possi#ility of modifications 9e3en at a late stage:

7 Local loads.

- + model allos all )ind of modifications #ut implies to redesign 9or rechec): the hole pipe rac)for a local modification. It allos also the introduction of local loads hich ill #e used only inspecific load com#inations for local design. *his ill imply a large increase of the num#er of loadcom#inations and the ris) to include local load com#inations. But usually confusion is made#eteen local loads and other loads. -ctually pipe rac)s include a large num#er of isostatic #eams9intermediate girders longitudinal girders #racing diagonals:. It is possi#le to split the holestructure in smaller elements intermediate girders longitudinal #eams trans3ersal frames and#racing #ays. ach element is then designed separately starting of course #y intermediate girders.;odels are 1+ or 2+ and are much simpler to handle so local design is easier as ell as design#y stages incorporation of modifications is also much easier. ?athering of similar elements ingroups is also possi#le. *his method is highly recommended for the design of pipe rac)s.

3.0 Structural 'ayout of *an) farm

*he use of tan)s is common in all )inds of plants found in oil V gas industry.

1. Process Plant2. (efineries

. Petrochemicals!. Specialty chemicals$. *erminals%. -dministration #uildings'. ;aterial 8andling Plants

Storage tan) are containers used for storage of fluids for the short or long term. Cluster of tan)stogether in a same are termed as W*an) FarmsX.

*ypes of *an)s,

*ypes of *an)s in Process plant depend on the product to #e stored potential for fire and capacity

to #e handled.

Cone roof tan),

Ksed for countless products including Petroleum Chemicals Petrochemicals Food products VHater

Floating roof tan),

*he roof of tan) rises and loers ith the stored contents there#y reducing 3apour loss Vminimi"ing fire ha"ard. Commonly found in >il refineries.

Lo temperature storage tan),

http://www.piping-engineering.com/types-of-fire-protection-systems.htmlhttp://www.piping-engineering.com/types-of-fire-protection-systems.htmlhttp://www.piping-engineering.com/types-of-fire-protection-systems.html


30/38

*an)s stores liuefied gases at their #oiling point. Products found in such tan)s include -mmonia 972G NF: Propane 97!.' NF: and ;ethane 972$GNF:.

8ori"ontal pressure tan) 9Bullet:,

Ksed to store products under high pressure.

8ortonsphere pressure tan),

8andles large capacity under high pressure.

Knderground *an)s,

Commonly used for drain collection of the plant at atmospheric pressure.

F(P *an)s,

Commonly used for corrosi3e fluid at atmospheric pressure.

Y


31/38

esign Considerations for *an)farm 'ayout>

Belo considerations are to ta)en into account hile designing a *an)farm for Process plants,

?eneral considerations,

• Local codes and regulations

• Client specification


32/38

• *opography

• -d5acent process units

• eigh#oring commercial and residential property

• ;aintenance and operation

+etail design,

• Identification of storage #ased on fluid stored.

• Safety considerations/Statutory reuirements

•

?eneral / Plot plan arrangement

• ?eneral piping layout

• ;aterial of Construction.

Statutory and Safety (euirements,

• Folloing are the )ey statutory reuirements 9India:. 8oe3er these are to #e

reloo)ed #ased on geographical location,

• >IS+ 711G 9 Plant Layout :

• >IS+ 711% / 11' 9Fire Fighting :

• Fire 8ydrant ;anual V Spray ;anual.

• Factory -ct of State. If -ny

• Petroleum -ct 1E! 9-ct 0.0 of 1E!: -long ith *he Petroleum (ules.

• Static and ;o#ile Pressure &essel 9S;P&:.

• ational Fire Protection -ct 9FP-:.

• -part from this local rules and regulations pertaining to State and local industrial

reuirement should #e ta)en into consideration.

• Safety ensures proper protection and safe operation7 Lifetime.

• Insurance Premium.


33/38

Plot Plan rrangement for *an)farm

• 8ydrocar#on processing and handling plants are inherently ha"ardous in3ol3ing

large and comple processes and su#stantial ris) potential4 hence a careful consideration shall #egi3en hile de3eloping a plot plan.

• Plot plan is a spatial arrangement of euipment considering proper flo seuence

system grouping safety statutory reuirements maintenance operation erection and constructionith logistical economy.

• ?eneral classification of petroleum products for storage.

1. Class = -, Flash Point #elo 2 NC

2. Class = B, Flash Point of 2 NC V a#o3e #ut #elo %$ NC.

. Class = C, Flash Point of %$ NC V a#o3e #ut #elo E NC.

!. cluded Petroleum class, Flash Point of E0 NC V a#o3e.

$. LP? doesnt fall under this classification #ut form separate category.

• ?rouping of petroleum products for storage shall #e #ased on product classification.

• Classification #ased on capacity and diameter,

1. Larger installations, -ggregate capacity of Class - and Class B petroleum product ismore than $000 cu.m or diameter of Class - or Class B product tan) is more than Em.

2. Smaller installations, -ggregate capacity of Class - and Class B petroleum productis less than $000 cu.m or diameter of Class - or Class B product tan) is less than Em.

• *he storage tan)s shall #e located at loer ele3ation here3er possi#le.

• *he storage tan)s should #e located donind of process units.

• +ue to ris) of failure of storage tan)s and primary piping systems means must #e

pro3ided to contain the spills. *he containment for petroleum storage tan)s is in the form of y)ed

enclosures.


34/38

y)e 9nclosure

•

-ggregate capacity in one dy)e enclosure,

1. ?roup of Fied roof tan)s, Kpto %0000 m

2. ?roup of Floating roof tan)s, Kpto 120000 m

. Fied cum floating roof tan)s shall #e treated as fied roof tan)s.

!. ?roup containing #oth Fied roof tan)s V Floating roof tan)s shall #e treated asfied roof tan)s.

• Class = - and / or Class = B petroleum products ,7 Same dy)ed enclosure

• Class = C, = Prefera#ly separate dy)ed enclosures.

• *an)s shall #e arranged in maimum to ros. *an)s ha3ing $0000 m capacities

and a#o3e shall #e laid in single ro.

• *he tan) height shall not eceed one and half times the diameter of the tan) or 20 m

hiche3er is less.

• *he minimum distance #eteen a tan) shell and the inside toe of the dy)e all shall

not #e less than half the height of the tan).


35/38

• +y)ed enclosure for petroleum class shall #e a#le to contain the complete contents

of the largest tan) in the dy)e in case of any emergency.

1. 8eight of +y)e 98:, 1m Z 8 Z 2m

2. Hidth of +y)e 9H:, ;inimum 0.%m 9arthen dy)e: ot Specific 9(CC dy)e:

Separation distances #eteen the nearest tan)s located in separate dy)es shall not #e less thanthe diameter of the larger of the to tan)s or 0 meters hiche3er is more.

• -ll process units and dy)ed enclosures of storage tan)s shall #e planned in separate

#loc)s ith roads all around for access and safety.

• In a dy)ed enclosure here more than one tan) is located firealls of minimum

height %00mm shall #e pro3ided to pre3ent spills from one tan) endangering any other tan) in thesame enclosure.

• For larger installation minimum separation distances shall #e as specified in

folloing ta#les.


36/38

y)e 8all 6eight Calculation>

-rea of +y)e , 21$G2.$ ;2

8eight of +y)e -ssumed , T8 D 1.2 ;

8eight of Foundation Th hich is 0.E;

+iameter of Foundation , T+ D +iameter of *an) O 1.$ ;

um#er of *an)s , Tn

Fire all dimensions , 200 ;; *h). [ %00 ;; 8igh

+y)e enclosure 3ol. \ Hor)ing capacity of Largest tan) O +ead 3olumes

- \ B O C

-: +y)e enclosure 3olume D -rea of +y)e [ +y)e 8eight

D 21$G2.$ [ 1.2 D2$GEE ;

B: Hor)ing capacity of Largest tan) D 1'0! ;

C: +ead 3olume D -ll tan)s foundation 3olume O Liuid 3olume of tan)s 9other than thelargest tan): upto the 8t. of the enclosure O +ead 3olume of Fire all

1: -ll *an) foundation 3olume,

&olume of a tan) foundation D ]/! +2 [ h [ n

Let

+1 , Fdn +ia of 00 tan) D '.$ ;4 +2 , Fdn +ia of 2$0 tan) D 2%.$ ;4 + , Fdn +ia of 210 tan) D

22.$ ;


37/38

n1 , um#er of 00 tan) fdns D 2 nos4 n2 , um#er of 2$0 tan) fdns D ! nos4 n , um#er of 210tan) fdns D % nos4

&olume of all tan) foundations D ]/! +12 [ h [ n1 O ]/! +22 [ h [ n2 O ]/! +2 [ h [ n

D ]/! [ '.$2 [ 0.E [ 2O ]/! [ 2%.$2 [ 0.E [ ! O ]/! [ 22.$2 [ 0.E [ %

D 1EGG.0! O 1EG$.$% O21!'.0G

D %120.%G ; ^^^^^^^^^^^^^^^^^^^..91:

2: Liuid 3olume of tan)s 9other than the Largest *an): a#o3e Fdn upto +y)e 8t,

Liuid 3olume of tan) a#o3e Fdn upto +y)e 8t. D ]/! d2 [ 987h: [ nD ]/! d2 [ 90.: [ n

Hhere d , +ia of *an)

n , um#er of tan)

*otal &olume of all tan)s 9other than the Largest *an): a#o3e Fdn upto +y)e 8t,

D ]/! d12 [ 90.: [ n1 O]/! d22 [ 90.: [ n2O]/! d2 [ 90.: [ n

D ]/! [ 9%:2 [ 90.: [ 1 O]/! [ 92$:2 [ 90.: [ !O]/! [ 921:2 [ 90.: [ %

D 0$.% O $GE.0$ O %2.!$

D 1$1'.G% ; ^^^^^^^^^^^^^^^^^^^..92:

: +ead &olume of Fire all D 0.2 [ 0.% [ 9$% O 1EEO ''.$ O ''.$ O ''.$ O ''.$ O ''.$: D ''.1 ;

D 100 ; 9;in +ead &olume of Sleepers V Crosso3ers: ^^^^^..9:

C: +ead 3olume D 91: O 92: O 9:

D %120.%G O 1$1'.G% O 100

D ''G.$! ;

B O C D 1'0! O ''G.$!

D 2$0!2.$! ;

- D 2$GEE ;

- _ B O C

+y)e height 91.2 ;: assumed is >IS+ 200 ;; free #oard is to #e added to +y)e height


38/38

+y)e Hall 8eight D 1.2 O 0.2

D 1.! ;

Structural layout

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