Pipe Instllation Guide Lines1

7/30/2019 Pipe Instllation Guide Lines1

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~AmlanlU q ~ . o - 1FIBERGlASS W " ' ~ ~-----

AMIANTIT FIBERGLASS INDUSTRIES LTD.PIPE INSTALLATION GUIDE LINES

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AMIANTIT FIBER GLASS IND. LTD. P.O.BOX 589DAMMAM 31421-SAUDI ARABIAPlease Visit Our Website www.afilpipe.com www.amiantit.com www.flowtite.com


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1.0 Introductory infotmation1.1 ForewordThis manual is intended to assist the installer inunderstanding the requirements and proceduresfor the successful handling and buriedinstallation ofAmiantit FIBERGLASS pipe. Itmay also be a helpful source of data for projectengineers.

The manual addresses most of the unusual, aswell as usual, circumstances that may beencountered in the field. Ask for AmiantitFIBERGLASS assistance for cases not covered.Also, installations other than direct bury, suchas sub-aqueous, partial buried, embankment, orabove ground on cradles, are not covered.Consult Amiantit FIBERGLASS for suggestedprocedures and limitations in these cases.Most importantly, this manual is not meant toreplace common sense or good engineeringjudgment, nor the specifications and instructionsof the owner's engineer, who is the finalauthority on all jobs. Should conflicts in any ofthese information arise that creates doubts ashow to proceed properly, please consultAmiantit FIBERGLASS and owner's engineerto obtain assistance.1.2 IntroductionThe excellent conosion resistance and manyother benefits ofAmiantit FIBERGLASS pipewill be realized if the pipe is properly installed.Amiantit FIBERGLASS pipe is designedconsidering the bedding and pipe zone backfillsupport that will result from these recommendedinstallation procedures. Together, the pipe andthe embedment material form a high-performance "Pipe/Soil y s t e m ' ~These instructions are easy to follow andmonitor. A good indication o f he quality o f heinstallation is immediately verifiable bymeasuring the vertical diametrical deflection ofthe buried pipe and by inspecting the pipe shape.

~ mlanw ~ 4 . - \fiBERGlASS 1 . 1 " ~ ~-----------------Initial deflections of the completely backfilledpipe should not exceed the values in Table 4.1.Bulges, flat areas or other abrupt changes ofcurvature are not permitted.Judgment of installation acceptability bymeasurement of initial vertical deflection is validonly when the specified installation procedureshave been followed, enabling long-term effectsto be reliably predicted.The installation procedures outlined in thisbrochure and the suggestions of the Field ServiceRepresentatives, when carefully followed, willhelp assure a proper, long-lasting installation.Consult Amiantit FIBERGLASS whenvariations in these instructions are beingconsidered.1.3 Field Service RepresentativeAmiantit FIBERGLASS can provide a FieldService Representative.The Field Service Representative will advicethe installer to help him achieve a satisfactorypipe installation. The "on the job" field servicewill be available early in the installation and maycontinue periodically throughout the project. Theservice will range from continuous (essentiallyfull time) to intermittent depending on the jobschedule, complexity and installation results.1.4 Fire SafetyGlass Reinforced Polyester (GRP) pipe can bum.During installation, care must be taken to avoidexposure of the pipe to welder's sparks, cuttingtorch flames or other heat/flame/electricalsources which could ignite the pipe material.This precaution is particularly important whenworking with volatile chemicals in making layup joints, repairing or modifying the pipe in thefield.


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2.0 Shipping, handling and storage2.1 Inspecting PipeAll pipes should be inspected upon receipt at thejob site to enswe that no damage has occurred intransit. Re-inspection of the pipe just prior toinstallation is advisable. Inspect the shipmentupon delivery, as follows:

I. Make an overall inspection ofthe load. Ifthe load is intact, ordinary inspection whileunloading will normally be sufficient tomake sure the pipe has arrived withoutdamage.2. If the load has shifted or indicates roughtreatment, carefully inspect each pipesection for damage. Generally, an exteriorinspection will be sufficient to detect anydamage.

3. If any imperfection or damage is found,immediately segregate the affected pipesand contact Amiantit FIBERGLASS.Do no t use pipe that appears damaged ordefected.2.2 Repairing PipeNormally, pipes with minor damage can berepaired quickly and easily at the job site by aqualified individual. I f n doubt about thecondition o f he pipe, do not use the pipe.The Field Service Representative can help youdetermine whether repair is required and weatherit is possible and practical. He can obtain theappropriate repair specification and arrange forthe required materials and a trained repairtechnician, if desired. Repair designs can varygreatly due to pipe thickness, wall composition,application, and type and extent of damage.Therefore, do no t attempt to repair a damagedpipe without consultingAmiantitFIBERGLASS first. Improper repairedpipesmay no tperform as intended.

2.3 Unloading and Handling Pipe

~Amlantu ~ \ . . o \FIBERGlASS 1 . 1 " ' ~ .- M-.-Unloading the pipe is the responsibility of thecustomer. Be sure to maintain control of the pipeduring unloading. Guide ropes attached to pipesor packages will enable easy manual controlwhen lifting and handling. Spreader bars may beused when multiple support locations arenecessary. Do 1101 drop, impact, or bump t" epipe, particularly at ends.2.3.1 Packaged Loads:Pipes 1400mm and smaller in diameter arepackaged as a unit. Packages may be handledusing a pair of slings as shown in Figure 2 .1.

Figure 2.1Lifting Pipe Package2.3.2 Single Pipes:Single pipes must be unloaded and handledseparately (one at a time). Use pliable straps,slings or ropes to lift single pipes. Do not usesteel cables or chains to lift or transport the pipe.Pipe sections can be lifted with only one supportpoint (Figure 2.2) although two support pointsplaced as in Figure 2.3 make the pipe easier tocontrol. Do not lift pipes by passing a ropethrough the section end to end.

See Appendix A for appropriate weights ofstandard pipes and couplings.If at any time during handling or installation

of the pipe, any damage such as gouge, crack, orfracture occurs, the pipe should be repairedbefore the section is installed. Contact AmiantitFIBERGLASS fo r inspection o fdamage andfo r recommendation fo r repair method ordisposal. See previous section on RepairingPipe.

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JA/\11/ANTIT

Figure 2.2Lifting Pipe at One Support Point

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~L Y. x L J.l xl Y.xl I' 1\\

Figure 2.3Lifting Pipe at Two Support Points2.4 Storing PipeIt is generally advantageous to store pipes on flattimber to facilitate placing and removal of liftingslings around the pipe.When storing pipe directly on the ground, besure that the area is relatively flat and free ofrock and other potentially damaging debris. Allpipes should be chocked to prevent rolling inhigh winds.

If it is necessary to stack pipes, it is best tostack on flat timber supports at maximum 6meter spacing (3 meter for small diameter) withchocks (See Figure 2.4).

__________________.Amlanlll ~ l , o lFIBERGlASS 1 . 1 " ~ ~------------------

Figure 2.4Storing PipeEnsure the stack will be stable for conditionssuch as high winds, un-level storage area orother horizontal loads. Maximum stack height isapproximately 2 meters. Stacking of pipes largerthan 1400mm diameter is not recommended.

Maximum diametrical deflection must notexceed the values in Table 2.1. Bulges, flatareas or other abrupt changes of curvatureare not permitted. Storing of pipes outsidethese limitations may result in damage to thepipes.Table 2.1Maximum Storage Deflections

Stiffness ClassSTIS (Pa)12502500500010000

Maximum Deflection(% ofDiameter)

3.02.52.01.5

2.5 Storing Gaskets and LubricantRubber ring gaskets, when shipped separatefrom the couplings, should be stored in the shadein their original packaging and should not beexposed to sunligh t except during the pipejoining. Also, the gasket must be protectedfrom exposures to grease or oils, which arepetroleum derivatives, and from solvents andother deleterious substances.

Gasket lubricant should be carefully storedto prevent damage to the container. Partiallyused buckets should be resealed to preventcontamination ofthe lubricant.

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A I V I I A N T I T

2.6 Transporting PipeIf it is necessary to transp01t pipes at the job site,support all pipe sections on flat timber spacedon a maximum of 4 meters centers (3 meter forsmall diameter) with 2 meters maximumoverhang. Chock the pipes to maintain stabilityand separation. Insure no pipes contact otherpipes, so vibrations during transport will notcause abrasion (Figure 2.5).Strap pipe to the vehicle over the supportpoints using pliable straps or rope- never usesteel cables or chains without adequatepadding to protect the pipe from abrasion.

Figure 2.5Transporting Pipe2.7 Handling Nested PipesPipes to be shipped long distances may be nested(smaller diameter pipes inside of larger sizes) toreduce the transportation cost. These pipesgenerally have special packaging and mayrequire non-standard procedures for un-loading,handling, storing and transporting. Non-standardpractices, if required, will be supplied prior toshipment. Regardless, the following generalprocedures should always be followed:1. Always lift the nested bundle using at leasttwo pliable straps (Figure 2. 6). Limitations,

if any, for spacing between straps andlifting locations will be specified for eachproject. Insure that the lifting slings havesufficient capacity for the bundle weight.This may be calculated from theapproximate pipe weights given inAppendix A.

Figure 2.6Double Support Point

- - - - - - - - - - - - - - - - ~Amw.W ~ 1 , - 1FIBERGlASS 1 . 1 " ' . ) \ . _ l : . ~

ControlRope

2. Nested pipes are usually best stored in thetransport packaging. Stacking of thesepackages is not advisable unless otherwisespecified.3. Nested pipe bundles can only be safely

transported in the original transportpackaging. Special requirements, if any, forsupport, configuration and/or strapping tothe vehicle will be specified for eachproject.4. Package removal and de-nesting of theinside pipe(s) is best accomplished at a denesting station. Typically, this consists ofthree or four fixed cradles to fit the outsidediameter ofthe largest pipe of the bundle.Inside pipes, starting with the smallest sizemay be removed by lifting slightly with aninserted paddle boom to suspend the sectionand carefully move it out the bundlewithout touching the other pipes (Figure2. 7). When weight, length and/or otherequipment limitations preclude the use ofthis method, procedures for sliding theinside pipe(s) out of the bundle will berecommended for each project.

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~"-7 hl"Z - ~- -ANIIANTIT 1\rnlnnut ~ t . ; . - \FIBERGLASS . . . r Y L . . . i : - ~-------------------

Figure 2.7nesting With Padc.)ed Boom on Forklift Truck

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--'MIVIIANTIT

3.0 Joining pipesAmitmtit FIBERGLASS pipe sections aretypically joined using GRP double bellcouplings. Pipe and couplings may be suppliedseparately or the pipe may be supplied with acoupling installed on one end.

Other joining systems such as flanges,mechanical couplings and lay-up joints mayalso be used with Amiantit FIBERGLASSpipe.3.1 Double Bell CouplingCleaning and Gasket InstallationThe following steps (1 to 4) apply to all doublebell coupling-joining procedures:Step 1: Clean CouplingThoroughly clean double bell coupling groovesand rubber gasket rings to make sure no dirt oroil is present (Figure 3.1).Step 2: Install GasketsInsert the gasket into the grooves, leaving twoor more uniform loops of rubber (dependingon diameter) extending out of the groove. Dono t put any lubricant in the grooves or on thegasket at this stage. There should be aminimum of one loop for each 450mm ofgasket ring circumference (Figure 3.2).With uniform pressure, push each loop of therubber gasket into the gasket groove.

When installed, pull carefully on the gasket inthe radial direction around the wholecircumference to check for well-distributedcompression of the gasket.Check also that both sides of the gasketprotrude equally above the top of the groovearound the whole circumference.Tapping with a rubber hummer will behelpful to accomplish the above.

Step 3: Lubricate GasketsNext, using a clean cloth, apply a thin film oflubricant to the rubber gaskets (Figure 3.3). SeeAppendix B for normal amount of lubricantconsumed per joint.

Figure3.1

Figure 3.2lnsfallin Gaskets

Figure 3.3Lubricatin

Figure 3.4Cleaning Spigot

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Step 4: Clean and Lubricate SpigotsT _ h o r o ~ g h l y clean pipe spigots to remove anydut, gnt, grease, etc. Using a clean cloth, apply athin film oflubricant to the spigots fiom the endof the pipe to the black positioning stripe. Afterlubricating, take care to keep the coupling andspigot clean (Figure 3.4).Caution: It is very important to use only thecorrect lubricant. Amia11tit FIBERGLASSprovides sufficient lubricant with each deliveryof coupling. If for some reason you run out,please contact Amitmtit FIBERGLASS foradditional supply or advice on alternativelubricants . Never use a petroleum basedlubricant.Step 5: Fixing of ClampsClamp A is fixed anywhere on first pipe or left inposition from previous joint. Fix Clamp B on thepipe to be connected in the correct positionrelative to the alignment stripe on the spigot-end(home-line) so as to act as a stopper (Figure 3.5).Note: The mechanical installation clamp is to actboth as a stop to position the coupling and as adevice on which to attach the pulling (comealong jacks) equipment. Clamp contact with thepipe shall be padded or otherwise protected toprevent damage to the pipe and to have highfriction resistance with the pipe surface. Ifclamps are not available, nylon slings or ropemay be used as in Figure 3.6, but care must betaken in the alignment of the coupling. A pipeclamp has the advantage of acting as a stopper.However, if not available, insert the pipe spigotsuntil the home-line (alignment stripe) aligns withthe coupling edge.

Figure 3. 5Clamp Location

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Step 6: Pipe PlacementThe pipe to be connected is placed on the bedwith sufficient distance from previously joinedpipe to allow lowering the coupling into position.

Figure 3.6

"Co m e -al o ng jack ' '(o ne o n each s id e)

1SF -J :::sl -_lIPlank on both Nylon o rsides to prev en t rope slingpipe dam ag e

Pipe Joining Without ClampStep 7: Join CouplingCome-along jacks are installed to connect thepipe clamps and two 1Ocm x 1Ocm timbers orsimilar (larger diameters require a bulkhead) areplaced between the pipe previously connectedand the coupling. While these are held inposition the new pipe is entered into the couplinguntil it rests against the pipe clamp. Come-alongjack might need protective blanket under it inorder not to touch against the pipe (Figure 3. 7).Note: Approximate joining force 1 kg/mm ofdiameter.Note: For smaller diameter (80 to 300mm) i tmight be possible to joint pipe and couplingwithout the use of come-along jacks. The use oflevers is common to join small diameters.

Woo d (1 0 em x 10 em )

Wood (1 0 em>< 10 em )

Figure3.7Join Coupling

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Step 8: Join PipesCome-along jacks are loosened and timbersremoved before re-tightening the jacks forentering the coupling onto the previouslyconnected pipe. Check the conect position of theedge of he coupling to the alignment stripe(Figure 3.8).Note: When step 8 has been completed, ClampB is left in position while Clamp A is moved onto the next .i e to be 'o ined .

Figure 3.8Pipe Joining

Table 3.1Angular Deflection at Double BeJI Coupling Joint \ 2

__________________Am1anJu 1.=-ZI..olFIBERGlASS W " " ~ . - " - .-

3.1.1 Angular Deflection of Double BellCouplings:Maximum angular deflection (tum) at eachcoupling joint must not exceed the amountsgiven in Table 3.1. The pipes should be joined instraight alignment and thereafter deflectedangularly as required (Figure 3.9).

Coupling

Figure 3.9Double Bell Coupling Angular Deflection

Nominal Offset Nominal Radius ofCurvatureNominal Pipe Angle of (mm) (m)Diameter Deflection Pipe Length Pipe Length(mm) (Degree) 3m 6m 12m 3m 6m 12m

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3.2 Flanged JointsGRP flanges with diameter 350mm and largershould be jointed according to the followingprocedure: (Figure 3.10)

1. Thoroughly clean the flange face and the'0 ' ring groove.

2. Ensure the '0 ' ring gasket is clean andundamaged. Do not use defective gaskets.

3. Position the '0 ' ring in the groove andsecure in position, if necessary, with smallstrips of adhesive tape.4. Align flanges to be jointed.

5. Insert bolts, washers, and nuts. Allhardware must be clean and lubricated toavoid incorrect tightening. Washers must beused on all GRP flanges.

6. Using a torque wrench, tighten all bolts to35 N.m (25 lb.ft) torque, following standardflange bolt tightening sequences.

7. Repeat this procedure, raising the bolttorque to 70 N .m (50 lb.ft) or until theflanges touch at their inside edges. Do notexceed this torque. To do so may causepermanent damage to the GRP flange.

8. Check bolt torque one hour later and adjustif necessary to 70 N.m.Note: When connecting two GRP flanges, only

one flange should have a gasket groove in theface.

MetalFlange

Figure 3.10Flanged Joints (Dia. 350mm)3.3 Other Joining Methods

FiberglasFlange

'0 ' Ring Gasket

3.3.1 Flexible Steel Couplings:(Straub, Tee Kay, etc. -See Figure 3.11)

~ ~.Amlo.nw ~ 4 . - 1fiBERGlASS L l " ' ~ ~-

These couplings can be used for join ing as wellas for repair. The coupling consists of a steelmantle with an interior rubber-sealing sleeve.Three grades are available:A. Epoxy or PVC-coated steel mantle.B. Stainless steel mantle.C. Hot dip galvanized steel mantle.

Control ofbolting torque with these couplingsis most important. After initial bolt up, thecoupling should be rapped with a rubber malletto help seat and flow the gasket. Bolt torqueshould then be adjusted up to proper levels.Depending on coupling size, this procedure mayneed to be repeated several times. Do not overtorque as this may over stress the bolts. Followthe manufacturer's recommended assemblyinstructions.

Figure 3.11Flexible Steel Coupling

3.3.2 Mechanical Steel Couplings:(Viking Johnson, Dresser etc.- See Figure 3.12)These couplings can be used for joining,typically to other types of pipe or to rigid items.Bolting torque must be controlled to notexceed the manufacturer's maximumrecommended values. Excess torque coulddamage the pipe.

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Flange Sleeve Flange~ ~askets PiJ>f' 00Figure 3.12Mechanical Steel Coupling3.3.3 Special GRP Couplings3:(Step GRP coupling, Special GRP Double BellCoupling, etc.- See Figure 3.13).These couplings can be used for joining to othertypes of pipe like concrete, asbestos or ductileiron pipes. Contact Amiantit FIBERGLASS forfurther advice on the supply of such type ofspecial GRP couplings.

Figure 3.13Special GRP Step-CouplingBuried flexible and mechanical steel couplingsoften require special corrosion protection with asleeve or shrinkable polyethylene or other meansas approved by the engineer. while special GRPcouplings do not require corrosion protection.Manufacturer's assembly instructions will beprovided for the type supplied.

3 Amiantit FIBERGLASS can supply different types oftie-in connections with existing pipe or structures. ContactAmiantit FIBERGLASS for further details on yourrequirements.

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~ I A N TIT

4 Standard installationThe type of installation appropriate for Am an itFIBERGLASS pipe varies with pipe stiffness,cover depth and native soil characteristics.The native material must adequately confinethe pipe zone backfill (see Figure 4.1) to achieveproper pipe support. The following installa tionprocedures are intended to assist the installer inachieving an acceptable pipe installation.However, regardless of soil conditions andinstallation method, the initial and long-termdeflections must not exceed the values given inTable 4.1. Pipes installed outside these limitsmay not perform as intended.In Table 4.2 are descriptions of the nativesoil groups.

Appendix C gives more detailed definitionsfor the native soil groups. Testing of native soilshould be done frequently and particularly wherechanges are suspected. Properties of importanceTable 4.1Allowable Vertical Deflection(% of Diameter)

Nominal Pipe DiameterDN2:350mmMaximum Allowable

2

Initial Deflection 3.5% 3.25%Maximum AllowableLong-Term Deflection 5.0% 5.0%

DN$300mm 2Maximum Allowable

Initial Deflection 2.5% 2.5%Maximum AllowableLong-Term Deflection 4.0% 4.0%

Table4.2Native Soil Group Classification4 5Soil Group 2Cohesive Hard&

(Fine Grained2 Very Stiff StiffGranular

4 See Appendix C for more detailed definition.5 See Appendix D for soil group classification of native soils.

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are those obtained at the bed and pipe zoneelevation. The blow counts or soil strengths mustrepresent the most severe (weakest) conditionexpected to exis t for any significant period oftime. (Normally this occurs when the water tableis at its highest elevation). Appendix D relatesthe consistency of cohesive soils andcompactness of granular soils to variousengineering properties characteristic of these soiltypes.

u n c t , c ~ t i o n(if requ1red) - - - ----"--------"Mrn DN/4M a x . lS O m m

Figure 4.1Pipe Backfill Nomenclature

Native Soil Group3 43.0% 2.5%5.0% 5.0%

3 42.0% 1.5%4.0% 4.0%

3 4

52.0%5.0%

51.5%4.0%

5

Medium Soft Very Soft

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~..: t'l ..- -/A/\11/ANT/T

(Coarse Grained) Very Dense DenseBlow Counts >30 16-30

4.1 Standard TrenchIn general, the trench shall always be made wideenough to pennit placement and propercompaction of the pipe zone backfilling material.Minimum trench dimensions shall meet thelimits shown in Figure 4.2

Minimum Trench WidthDN (mm) A(mm)80 to 300 150350 to 500 200550 to 900 3001000 to 1600 4501700 to 2400 600

2500 to 4000 750Figure 4.2Standard Trench DetailsWhere rock, hardpan, soft, loose, unstable orhighly expansive soils are encountered in thetrench bottom, it may be necessary to increasethe depth of the bedding layer to achieveadequate longitudinal support. Dimension "A"must allow for adequate space to operatecompaction equipment and ensure properhaunching of the pipe. This can necessitate alarger trench than the minimum specified above.4.2 Backfill MaterialsMost coarse-grained soils, (gravel, crushedstone, and sand) are the recommended pipe zone

__________________.Amianlll ~ l . , o lFIBERGlASS L r ~ ~-

Medium Loose Very Loose6-15 3-5 0-3

backfill materials. Gravel is easier to compactthan sand and allows the pipe to be installeddeeper

4.2.1 Use of Native SoilsWhere native soil is used as pipe zone backfill,the following restrictions apply:

1. No rocks greater than maximum gravelsize in Table 4.3.2. No soil clumps greater than 2 times themaximum gravel size.3. No organic material.4. No debris (tires, bottles, metals, etc.).5. Where compaction is specified: thenative soil must be granular in nature(classification).

4.3 Backfill Migrat ion CriteriaWhen selecting the backfill materials, it isnecessary to check its compatibility with thenative soil. It is very important that the pipe zonebackfill material not washes away or migratesinto the native soil. Likewise, potential migrationof the native soil into the pipe zone backfill mustbe prevented. Should this happen, the pipe mayloose its side support, deflect excessively and notperform as intended. Typically, migration canonly occur ifthere is movement of water in thepipe zone and the following relationship existsbetween the two adjacent soils:

0 85 finer::::; 0.2 D1s coarserWhere:

0 85 finer = sieve opening passing 85% of thefiner materialD 15 coarser= sieve opening passing 15% ofthe coarser material {Figure 4.3).

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__________________Amlanw . . . . ; w ~ o - 1FIBERGLASS 1 . 1 " ~ ~------------------

Where incompatible materials must be used,they must be separated by fi Iter fabric designedto last the life of the pipeline to prevent washaway and migration. The filter fabric mustcompletely surround the bedding and pipe zone

backfill material and must be folded over thepipe zone area in order to prevent contaminationof the selected backfill material.

Table 4.3Acceptable Pipe Zone Backfill Materials Gradation

GradationSpecificationGravel

Clean Sand

Sand

Maximum Particle Size

10 0' -o M.ater.al 85pc'ISSmgseve

0 0 01

Pipe DiameterLess than 600mm

600mm to 1600mmGreater than 1600mm

10

Acceptable Backfill()GW,GP

GW-GC, GW-GMGP-GC, GP-GMSW,SPSW-SC, SW-SMSP-SC, SP-SMSW,SPSW-SC, SW-SMSP-SC, SP-SM

Coarsurmat&ral

S1;,ve o p e n m g (m m rD B5 fmer D 1S coars er

Figure 4.3Backfill Migration Criteria

6 Unified soils classification systems- ASTM D2487

May be Acceptable Backfill

SM,SCGM,GC

Maximum Gravel or Stone Size13mm19mm25mm

7 Silty and clayey gravels (OM, GC, SM, SC) are acceptable pipe zone backfills for sand specifications only when:(Eoptimum1Esarurated) :S 4, in a drained, confined consolidation test; ASTM D2435, where E is the soil secant modulus.

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..... .....

"'-; t ~ -- .....j ~ I A N T I T4.4 Burial Limitation- Maximum8Because Amiantit FIBERGLASS pipes areflexible conduits, they must be supported by thesurrounding soil to carry the overburden loads.The allowable cover depths are related to:

(1) The type of pipe zone backfill materialand its compaction (density).(2) Native soil characteristics.(3) Trench construction, and(4) Pipe stiffness.Four standard installation types are used.

Selection depends on:( l) Pipe stiffness.(2) Native soil, and(3) Required depth ofbury.Table 4.4 gives general guidelines for thefour installation types.

8 Regardless of soil conditions and installation methods,the initial and long-term deflections must not exceed thevalues given in Table 4.1.

_____J!Amlanlll ~ " " ' ' FIBERGlASS I . I " ) L . . . . l : . . ~-

Installation Type 1 Careful I) con,toucicu bed Backfill 70'1f Rdati\e Densi1y Goa,el Backfill ~ o m p a ~ t e d to JOOmm over pip


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_J:r.JVIIANTIT

Table 4.4Standard Trench

Maximum Burial Depth- MetersInstallation Native Soil G r o u ~

? ; ~ e 1 2LDP , DN > 300mmSTIS 12501 7 42 6 33 4 2.54 NR NR

STIS 25001 11 62 7 43 5 34 NR NRSTIS 5000

1 13 82 8 53 6 44 5 3

STIS 100001 16 102 12 73 11 64 10 5

9 LDP =Large Diameter Pipe.10 NR =Not Recommended.

3 4

2.5 21.5 NRNR NRNR NR

5 43 2.52.5 NRNR NR

6 54 33 2.51.5 NR

9 76 55 44 3

________RJAmlanJjJ ~ ~ \FIBERGlASS 1 . 1 " ~ ~--------

5

NR10NRNRNR

NRNRNRNR

21NRNR

321.51

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Burial Limitation- MinimumThe following circumstances require minimumcover depth (in meters) as indicated:4.4.1 Traffic:All pipe zone backfill to grade must becompacted when traffic loads are to be present.Minimum cover restrictions maybe reduced withspecial installations such as concreteencasement, concrete cover slabs, casings, etc.(See Table 4. 5.)Table 4.5Surface Loads

Load Type

AASHO H20 (C)BS 153 HA (C2ATV LKW 12 (C)ATVSLW30{C2ATVSLW60(C2M.O.C. 11CooEerE80

Traffic (Wheel)Load

KN lb72 16,00090 20,00040 9,00050 11!000100 22,000160 36 000

Rail-Road4.4.2 High water table:

MinimumBurialDe)2th

m1.01.51.01.01.51.53.0

A minimum of0.75 diameter of earth cover(minimum dry soil bulk density of 1900kg!m\but not less than 1.0m for sizes above 300mmdiameter and not less than 0.6m for sizes 80 to300mm diameter, is required to prevent an emptysubmerged pipe from floating.

Alternatively, the installation may proceed byanchoring the pipes. If anchoring is proposed,restraining straps must he a flat material,minimum 25mm wide, placed at maximum 4.0mintervals. Consult Amiantit FIBERGLASS fordetails on anchoring and minimum cover depthwith anchors4.4.3 Negative Pressure:Allowable negative pressure is a function of:11 Ministry Of Communication (M.O.C.) - Saudi Arabialoading

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( 1) Pipe stiffness.(2) Burial depth, and(3) Type of installation.

In Table 4.6 maximum allowable negativepressures are given.Table4.6Allowable Negntive Pressures

Allowable Negative Pressure (Kpa)13 14STIS 15 STIS 16 STIS STISnstallationTypet2 1250 2500 5000 10000-50 17 -100 -100 -100

-75 to Sm-100 to 3m2 25 -25 -75 -100-50 to 4m -100 to 6m

-25 -50 -100-75 to 4m

4 NR NR -25 -100-50 to 4m4.5 Pipe BeddingPipe bedding material shall he sand or gravel inaccordance to the requirements of section 4.2(Backfill Materials). The bedding shall he placedafter the trench bottom is compacted so as toprovide proper support. Minimum compaction ofthe bed shall he 90% Standard Proctor Density(70% of maximum relative density for crushedrock, crushed stone or gravels).

The finished bed shall be plane, shall have aminimum depth equal to DN/4 (maximum150mm required for sizes below 2500mmdiameter and 200mm for sizes above 2500mmdiameter) and must provide uniform andcontinuous support to the pipe. The bed must heover-excavated at each joint location to ensurethat the pipe will have a continuous support and12 Refer to Figure 4.4 for standard installation types.13 100 Kpa= I bar.14 For maximum cover depth, see Table 4. 4.IS sn = Specific Initial Tangential Stiffness= Elill3expressed in Pa or N/m l.16 Required minimum burial depth of 0.5 DN, but not lessthan l.Om.17 The first number represents the pipes allowable negativepressure at its maximum allowable cover depth, (Table4.4)18 Allowed only for clean sand (


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docs not rest on the couplings. However, thisarea must be properly bedded and backfilledafter the joint assembly is completed. SeeFigures 4.5 and 4.6 for proper and improperbedding support.

____J).Auh \. l i l t - - ; . Fl BE RGL.A.SS .r ~ . , . . _ _ _ ; _-

17


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~..: , . ~ ..- -NI IANTIT

Figure 4.5Proper Bedding Support

f \

(0)

Figure 4.6Improper Bedding Support4.6 Backfilling PipeImmediate backfilling after joining is desirableas it will prevent two serious hazards -floatingof pipe and thermal movements. Floating of pipecan damage the pipe and create unnecessaryreinstallation costs. Thermal movement causedby exposure to the elements can cause the loss ofseal due to movement of several lengths actingon one joint.Proper selection, placement, and compactionof pipe zone backfill is important for controllingthe vertical deflection and is critical for pipeperformance. Attention must be paid so that thebackfill material is not contaminated with debrisor other foreign materials that could damage thepipe or cause loss of side support. Duringbackfilling, the granular material should flowcompletely under the pipe to provide fullsupport. A blunt tool maybe used to push andcompact the backfill under the pipe, withoutraising the pipe up (See Figures 4. 7 and 4.8).Proper backfilling should be done in 150mm to300mm lifts depending on backfill material andcompaction method. When gravel or crushed

_________ !,Amlanill ~ l o - 1FIBERGlASS I J " ~ -" --------------

stone is used as backfill material, 300mm liftswill be adequate since gravel is relatively easy tocompact. Sand needs more compactive effort andthe lift height should he limited to 150mm. Pleasenote that it is important to achieve propercompaction of each lift to ensure that the pipewill have adeguate suwort.

Us e board orother deviceto push an dcompactembedmentmaterial underpipe .

Bedding Correct: Pipe f i rmly supportedFigure 4.7Ensuring Firm Pipe Support

X

Figure 4.8Improper Haunch

WRONG !

The compaction of sandy backfill is most easilyaccomplished when the material is at or near itsoptimum moisture content. When backfillingreaches pipe spring-line, all compaction shall bedone first near the trench sides and proceedstowards the pipe.It is recommended that placing andcompacting of the pipe zone backfill is done insuch a way as to cause the pipe to ovalizeslightly in the vertical direction. Initial verticalovalization must not exceed 1.5%- ofpipediameter as measured when backfill reaches pipeCrown.Table 4. 7 shows the minimum cover height overthe pipe necessary before certain compactionequipment may be used directly above the pipe.

18


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~~ .. ..- -V!.JVIIANTITCare must he taken to avoid excessivecompactive effort above the pipe crown, whichmay cause bulges or flat areas. However, thematerial in this area must not he left loose andthe desired specific density should he achieved.

Table4.7Minimum CoverDepths For Compaction Above Pipe10

EquipmentWeight (Kg)< 100

100 to 200200 to 500500 to 1000

1000 to 20002000 to 40004000 to 80008000 to 1200012000 to 16000

Minimum Pipe Cover (mm)Tamped Vibrated250 150350 200450 300700 450900 6001200 8001500 10001800 12002200 1500

20 It is may be necessary to begin with higher covering sothat, as compaction is achieved, the cover will not be lessthan minimum.

( r > )--------- -------.Am!anw ~ t . . . \FIBERGlASS 1 . 1 " ~ .- M-.----------------

19


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5 Alternate installationI f he burial depth requirement for the selectedpipe stiffness, installation type, and native soilgroup exceeds the limits given in Table 4.4,select higher stiffi1ess pipe or consider using oneof the alternative installation procedures.

Three alternative installation methods areavailable:

Wide Trench. Permanent Sheeting. Cement Stabilized Backfill.

5.1 Wide TrenchIncreasing the trench width distances the poornative soil (Native Soil Group 3. 4 or 5) fartherfrom the pipe allowing a deeper installation inthe native soil groups 3, 4 or 5. Trench widths of3 to 4 times the pipe diameter for LargeDiameter Pipes ( L D P ~ 3 5 0 m m ) or 4 to 5 timesthe pipe diameter for Small Diameter Pipes(SDP::;300mm) could allow increasing themaximum allowable cover depths above valuesstated in Table 4.4 for the three native soilgroups 3, 4 or 5. Consult AmiantitFIBERGLASS for maximum allowable coverfor each case.5.2 Permanent SheetingUse permanent sheeting of ufficient length (atleast 300mm over pipe crown) to appropriatelydistribute the pipe's lateral loads and ofsufficient quality to last the design life of thepipe. (See Figure 5.1.)

Note that backfilling procedure andmaximum cover depths are the same as forstandard installations.

Sheeted trench

15 035 0 to 500 20060 0 to 900 300~ 0 0 0 to 1600 45 01800 to 2400 60 0

Figure 5.1

- - - - - - - - - - - - - - - - - - ~AmlanW ~ 4 - 1FIBERGlASS 1 . 1 " ~ ~------------------

f' As requ.red by nI ' - shee t i ng desgn...., 1I !Tvp.l I II IIIIIII

: IuIu

Permanent Sheeted Trench5.3 Cement Stabilized BackfillTypically, around 50Kg of cement per ton ofsand (around 5% cement) will be sufficient. Thesand shall have a maximum of 12% passing a200 sieve. Seven-day strength of the stabilizedmaterial should be 690-1380kPa.The stabilized backfill should be compactedto 90 SPD in layers of 150 to 200 mm. Thestabilized material mus t be allowed to "set" 24hours at maximum initial cover beforebackfilling to grade. Maximum initial cover isequal to:

l.Om for STIS 1250 and 2500Pa1.5m for STIS 5000 and lOOOOPa.The pipe must be surrounded in stabilizedbackfill as shown in Figure 5.2. Maximum pipelength is 6 meters.

20


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FigUJe 5.2Sta bilized Backfill

Over-excavation must be fi ied withcom pacted stabilized material and as trenchboxes or temporary sheeting is pulled thestabilized backfill must be com pacted against thenative so i l. Maximum total cover depth is 5meters.

21


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"A/VIIANTIT

6 Other Installation Procedures6.1 Multiple Pipes In Same TrenchWhen two or more pipes are installed parallel inthe same trench, clear spacing between the pipesshall be as per Figure 6.1. Space between pipeand trench wall shall be as Figure 4.2.

It is advisable when laying pipes of differentdiameters in the same trench, to lay them invertto-invert. When this is not possible, selectbackfill material must be used to fill all the spacefrom the trench bottom to the invert of the higherpipe. Proper compaction must be achieved.

Figure 6.1

but no t less t h an 1 5 0 mm o rsuff icient room to place andco mp ac t backfi l l

Spacing Between Pipes in the Same Trench6.2 Cross-OverWhen two pipes cross, so that one passes overthe other, vetiical spacing between pipes andinstallation for the bottom pipe shall be as perFigure 6.2.

r, + r2f 2 - 2 - b u t no t Jess t h a n 150 mrn

Figure 6.2Cross Over

__________________Amlanu1 ~ 4 . - 1FIBERGLASS 1 . 1 " ' ~ ~------------------

In some cases, it is necessary to lay a pipeunder an existing line. Extra care should he takennot to damage the existing pipe. It should heprotected by fastening it to a steel beam crossingthe trench. It is advisable to also wrap the pipe inorder to protect it from impact damage. Whenthe new pipe is laid, selected backfill materialmust be placed back into the trench and handcompacted in order to completely surround bothpipes and also achieve the required density.6.3 Unstable Trench BottomWhere the trench bottom has soft, loose orhighly expansive soils, it is regarded as unstable.An unstable trench bottom most he stabilizedbefore laying pipe or a foundation must beconstructed to minimize differential settlementof the trench bottom.The depth of the gravel or crushed stone

material used for foundation depends upon theseverity of the trench bottom soil conditions, butshould not he less than 150mm. The normalbedding must be placed on top of suchfoundations. The use of filter cloth to completelysunound the foundation material will preventfoundation and bedding materials from migratinginto one another that could cause loss of pipebottom support. Additionally, the maximum pipesection length between flexible joints shall be 6meters.6.4 Flooded TrenchWhen the ground water table is above the trenchbottom, the water level must be lowered to atleast the trench bottom (preferably about 200mmbelow) prior to preparation of the bed. Differenttechniques may be used depending on the natureof the native material.For sandy or silty soils, a system ofwell

points to a header pipe and a pump isrecommended. The spacing between individualwell-points and the depth at which they will bedriven, depends on the ground water table. It isimportant to use a filter around the suction point(coarse sand or gravel) to prevent clogging of thewell-points by fine grained native material.

22


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When the native material consists of clay orbedrock, well-points will not work. Dewateringis more difficult to achieve in this case if theground water table is high. The use of sumps andpumps is recommended.

If the water cannot he maintained below thetop of the bedding, subdrains must be provided.The subdrains shall be made using single sizeaggregate (20-25 mm) totally embedded in filtercloth. The depth of the subdrains under the bedshall depend on the amount of water in thetrench. If the ground water can still not bemaintained below the bed, filter cloth shall beused to surround the bed (and if necessary thepipe zone area as well) to prevent it from beingcontaminated by the native material. Gravel orcrushed stone shall be used for bed and backfill.The following cautions should be noted whendewatering:

Avoid pumping long distances throughthe backfill materials or native soils,which could cause loss of support topreviously installed pipes due to removalof materials or migration of soils. Do not turn of f the dewatering systemuntil sufficient cover has been reached toprevent pipe flotation.

6.5 Use of Temporary Trench ShoringIf at all possible, the use oftemporary trenchshoring or sheeting at pipe level should beavoided. This is because it is important that thebedding and pipe zone backfill are compactedhard against the native trench wall. If the shoringor sheeting is pulled out after backfill. the pipezone material will tend to move into the gap leftby the sheeting, reducing support to the pipe, andin many cases, resulting in excessive deflectionsof the pipes.

In cases where temporary shoring and sheetingare necessary and cannot be avoided, thefollowing requirements should be met:

Install the shoring to a depth of300mmabove the top of he pipe. leaving thenative trench sides fully exposed at pipelevel.

-----2'Amlanw ~ l e - IFIBERGlASS 1 . 1 " ~ ~-

Use a type of shoring, which can beremoved in stages either by pulling upindividual sheets or by pulling up thebottom panel of a trench systemindependent of the upper panels. Thislifting of sheets or panels must he doneprogressively so that pipe bedding andpipe zone material can be compactedhard against the native trench side up to300mm above the pipe crown forInstallation Type-1 and 2, to the pipecrown for Installation Type-3, and to60% of the pipe diameter for InstallationType-4.

Use trench boxes. It is fairly easy to pullthem in stages using a crane or excavator.Note: if water and/or native soil are seen toescape between sheets then there are certain tohe voids. These must be filled with compactedbackfill.6.6 Trench Construction In RockMinimum dimensions for pipe installations in arock trench shall be per Figure 4.2. Where therock ends and the pipe passes into a soil trencharea (or reverse), flexible joints shall he locatedas shown in Figure 6.3. Trench constructionshall be according to the method applicable forthe native soil condition.

Short section lengthlexible joint locatedat drop-off potnt Max.- Smaller of 2 m or 2 x DMin .- Smaller of 1 m or 1 x D

Figure 6.3Method of Trench Construction and Pipe Layout atRock-Soil Trench Transition6.7 Inadvertent Over-Excavation

23


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~......- .. .. "- -ANIIANTIT

Any inadvertent over-excavation of the lrenchwalls or the trench bottom in the foundation, bedor pipe zone areas shall be filled with compactedbackfill material. The native material shall not bereturned into these areas regardless of thecompacli.on level unless it qualifies as thebackfill material.

I An.n'l ~ " ' '

IFIBERGLASS _ r ' ) ! . . _ j . _ ~

24


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__________________.Amlanlu ~ l , o lFIBERGlASS 1 . 1 " ~ ~-

7 Thrust Blocks, Concrete Encasement and Rigid Connections7.1 Thrust RestraintsWhen the pipeline is pressurized, unbalancedthrust forces occur at bends, reducers, tees, wyes,bulkheads and other changes in line direction.These forces must be restrained in some mannerto prevent joint separation. When thesurrounding soil cannot provide this restraint,thrust or stress I thrust blocks must be used.Determination of need and design of theserestraints is the responsibility of the owner'sengineer subject to the following limitations:

Thrust BlocksThrust blocks must limit the displacement of thefitting to 0.5% of the diameter or 6mmwhichever is less. The block must completelysurround the fitting for its entire length andcircumference (Figure 7.1) and should be placedeither against undisturbed earth or backfilledwith pipe zone materials as appropriate for thenative soil characteristics. See sections onConcrete Encasement (Section 7.2) and RigidConnections (Section 7.3) for details of pipeinstallation and system layout. These blocks areapplicable to:

1- All bends, reducers, bulkheads and blindflanges.

2- Tees21 , when the branch pipe isconcentric to the header pipe centerline.Thrust/Stress Blocks

Thrust/stress blocks must limit the displacementof the fitting to 0.5% of the diameter or 6mmwhichever is less. They must also restrict theradial deformation of the fitting to 0.1% of theradius of the respective pipe sections. The block21 Concentric man-ways (blind flange tees) smaller thanhalf of the header pipe diameter do not requireencasement.

must completely surround the fitting for its entirelength and circumference (Figure 7.1) andshould be placed either against undisturbed eatthor backfilled with pipe zone material asappropriate for the native soil characteristics.

These blocks are required for the followingfittings when the line pressure exceeds I bar(lOOkPa), (See Figure 7.2.)

1- Tees, when the branch pipe is eccentric tothe header pipe centerline.

2- Lateral wyes.3- Bifurcations.4- Custom fittings as noted by special

instructions.7.1.1 ValvesValves must be sufficiently anchored to absorbthe pressure thrust.Note: It is not necessary to encase nozzleconnections in concrete.

Nozzles are tee branches meeting all thefollowing criteria:

1- Nozzle diameter :S 300mm.2- Header i a m e t e r ~ 3 times nozzlediameter.3- If the nozzle is not concentric and/or not

perpendicular to the header pipe axis, thenozzle diameter shall be considered to bethe longest chord distance on the headerpipe wall at the nozzle/pipe intersection.

7.2 Concrete EncasementWhen pipes must be encased in concrete, such asfor thrust blocks, stress blocks, or to carryunusual loads, specific additions to theinstallation procedures must be observed.These are:7.2.1 Pipe Anchoring

25


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..rru\11/ANT/T

During the pouring of the concrete, the emptypipe will experience large uplift (flotation)forces. The pipe must be restrained againstmovement that could be caused by these loads.This is normally accomplished by strapping overthe pipe to a base slab or other anchor(s). Strapsshould be a flat material ofminimum 25mmwidth, strong enough to withstand flotation upliftforces, spaced not to exceed 4 meters, with aminimum of one strap per section length. Thestraps should be tightened to prevent pipe uplift,but not so tight that additional pipe deflection iscaused (Figure 7.3).

Figure 7.3Pipe AnchoringPipe Supports

The pipe should he supported in such a way thatthe concrete can easily flow completely aroundand fully underneath the pipe. Also, the supportsshould result in an acceptable pipe shape (lessthan 3% deflection and no bulges orflat area).Supports are normally placed at strap locations(not exceeding 4 meter spacing) (Figure 7.4).

Figure 7.4Pipe Support

max4 meters

c ea r area

------.!!'Am1anut ~ 1 . . - 1FIBERGlASS 1 . 1 " ~ ~-

7.2.2 Concrete PouringThe concrete surround must be placed in stagesallowing sufficient time between layers for thecement to set (no longer exert buoyant forces).Maximum lift height is variable with nominalpipe stiffness:STIS 1250 -Smaller of300mm or 1/41h DN22 STIS 2500 -Smaller of300mm or 1/41h DN.STIS 5000 -Larger of 450mm or 12 pipe DN.STIS 10000 -Larger of 600mm or 12 pipe DN

7.3 Rigid ConnectionsWhen a pipe passes through a wall, is encased inconcrete, meets a junction with a manhole, or isflanged to a pump, valve, or other structure,excessive bending stresses may develop in thepipe if differential movement occurs between thepipe and the rigid connection.For all rigid connections action must be takenby the installer to minimize the development ofhigh discontinuity stresses in the pipe.Two options are available. Alternate A(prefened) uses a coupling joint cast into theconcrete-pipe interface. Alternate B wraps thepipe in rubber to ease the transition.7.3.1 Alternative AWhere possible, cast a coupling joint in theconcrete at the interface (Figure 7.5) so that thefirst pipe outside the concrete has completefreedom of movement (within the join t limits).

22 DN = Pipe Nominal Diameter.26


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Coupling Cost ----,in ConcreteSpec ial Pipe ~ 1- max . ~Shon Pipe Section1 -----._ 25mm .

Ma)C . -Smallerof2mor2xD \ ,"' _ -:-:": : . :Min . - Smaller of 1m or 1 x D - " " ' . "" ' .. .. .., .. . ' . .

Fill below pipe to str ucture baseshall be same as pipe zone materinl (Typ.)

Figure 7.5Alternative A

Caution:

max.45 A

.. ' t . . . .. .' ..: ..._ .. . ' . . .. : ....... .,. .. ... . . ..

1- When casting a coupling in concrete, besure to maintain its roundness so laterjoint assembly may be accomplishedeasily. Alternatively, makeup the jointoutside the encasement prior to pouringthe concrete.2- Since the coupling cast in concrete isrigid23, it is important to minimize thevertical deflection and deformation of headjacent pipe24.7 3.2 Alternative BWhere A is not possible, wrap a band (or bands)of standard concrete encasement rubber (Table7-1 and Figures 7.7 and 7.8) around the pipeprior to placement of any concrete such that therubber slightly protrudes (25 mm) from theconcrete. Layout the pipeline so the firstcompletely exposed coupling joint is located adistance greater of(l/41h DN and 400mm) asshown in Figure 7.6.

23 Ensure the concrete keeps the joint rigidity (axial cracksare not developed allowing the coupling to expand).24 Short pipe section for Alternative A may require specialfactory reinforcement to maintain spigot roundness in theconcrete coupling for sizes above 1m in diameter. Ensurethe required reinforcement is provided by providing theproper information/drawings to Amiantit FIBERGLASS.

_________________AmlanJil ~ L o - 1FIBERGlASS 1 . . 1 " ~ ~-

Slandard FLOWTITE Pipeconcrete encasement rubber,50 Durometer Neoprene,dimensions and wrapcontigurations perFigures 7.7 and 7.8.

Figure 7.6Alternative A

Table 7-1

max 45' A_

Quanti!;r and Configuration of RubberSTIS 1250 I 2500Dia. Pressure C l a s s ( ~ a ~

~ m m ) 1500


29/43

..,.. ..,..~ I A N T I T

j_) 150mm 410mmli \ IVVVVWVWVJ ~ m-t t

Figure 7.8Wrap Configuration26

7.3.2.1 Construct ion Details1- When the design ofthe concrete structureis considered, it should be noted that anyexcessive settlement of the structurerelative to the pipe could be the cause ofa pipe failure.2- The pipeline layout shall be such that thefirst pipe section near the rigidconnection is a short length as follows:(See Figures 7.5 and 7.6.)

a. For Sizes up to 300mm diameter,short piece length is 300 to 500mm.b. For sizes 350 to 2500mm diameter,short piece length is

i. Minimum: Smaller of1m or 1diameter.

ii. Maximum: Smaller of2m or 2diameter.c. For sizes above 2500mm diameter,

short piece length is one diameterbut not more than 3m.3- Extra care and caution must be taken toreplace and properly compact backfilladjacent to the concrete structure.Construction of the concrete structurewill frequently require over-excavationfor formwork. etc. This extra-excavatedmaterial must be restored to a densitylevel compatible with surroundings or

26 The cross sec tion can be used without 4mm lips. Referto Table 7-1 and Figure 7.7.

-AmlanUI ~ ~ \FIBERGlASS 1 . 1 " ~ ~------------------

excess deformation or joint rotation27adjacent to the structure may occur7.4 Casing (Tunnels/Sleeves)When pipe is installed in a casing or inside asleeve, the following precautions should beobserved:

1. Pipes maybe placed into the casing bypulling (drawn) or pushing Gackingi8.2. Pipes should be protected from slidingdamage by the use ofwooden skidsattached to the pipe by strapping as

shown in Figure 7.9. Plastic SpacerUnits, or an FRP lamination rings spacedalong the pipe length can also be used.Skids, Plastic Spacers, or FRPLamination rings must provide sufficientheight to permit clearance between thecoupling joints and the casing wa11293. installation into the casing is madeconsiderably easier by using lubricantbetween the skids and the casing wall. Donot use a petroleum-based lubricant as itmay cause harm to some gaskets.4. The annular space between the casing andpipe may be filled with sand, gravel, orcement grout. Care must be taken to notoverstress or collapse the pipe during thisstep, particularly when grouting.Maximum grouting pressure is given in

Table 7.1.Do not wedge or brace the pipe in amanner to cause concentrated or pointloads on the pipe. Consult AmiantitFIBERGLASS prior to thisstep for advice on suitability of thechosen method.

27 Refer to Figure 7. 5 and Figure 7. 6 where the overexcavation near the rigid structure, like a thrust block,shall be done with maximum slope of 45.28 Additional pulling lugs can be provided.29 Note that in some cases, rigid lay-up joints (Section 3.4)may be used along the length of the sleeve. ContactAmia11tit FIBERGLASS for further advice.

28


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. . , ~ I A N T I T

WoodenSkid \

StrappingJ\I I

Typ.Figure 7-9Typical Skid ArrangementNote: If the pipe will be subjected to negativepressure. the pipe stiffness- installationcombination must he sufficient to withstand theload. Consult Amiantit F/BERGLASS foradvice.Table 7.1Maximum GroutPressure

STIS (Pa)12502500500010000

Maximum GroutPressure (KPa)

142754108

----------------.Anuanill ~ l...olFIBERGLASS I J " ~ .- _- ..------------------.

29


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~" ' - ~ ) .. :. ... ~ ~_AI\ I I IANTIT

8 Field Adjustment8.1 Length AdjustmentThe following procedure shall be followed torproper length adjustment:

1- Determine length required and mark asquare cut location on the selected pipe.

2- Measure pipe diameter at point of cutwith a circumferential Pl tape.3- Compare measurement with spigottolerance range given in Table 8.1. (Note:manufacturers may give the pipe aspecial marking (Adjustment Pipe) at thefactory indicating the entire pipe barrel iswithin spigot tolerance range). Select oneof these pipes (i f available) for the fieldadjustment to avoid spigot machining.

4- Cut the pipe at the appropriate locationusing a circular saw with a masonryblade.

5- If pipe diameter is within the spigottolerance range, clean the surface in thejointing area, sand smooth any roughspots and with a grinder bevel cut pipeend to ease assembly. No further grindingis necessary.

6- Ifthe pipe diameter is not in the spigottolerance range use a field lathe orgrinder and machine the jointing (spigot)surface to the tolerances as indicated inTable 8.1, Bevel pipe end. (See Figure8.1.)

~Amlanlll 1.=.J:o 1oooIFIBERGlASS 1 . 1 " ' ~ ~- ---------------~ s p ; g m w ; ~ CLBL

Pipe Wall

Figure 8.1Pipe spigot and bevel dimensions definition forcoupling joints. Note: For field closure section, doublethe spigot width (CL).Table 8-1

S ~ i g o t Dimensions and TolerancesDN Min. Max. CL BL~ m m l (mm) ~ m m l ~ m m } !mm}80 98.9 99.4 105 4100 118.9 119.4 105 4150 170.9 171.4 107 520010 222.3 222.8 107 5200 31 221.8 222.3 107 5250 273 .6 274.1 109 7300 325 .2 325.7 109 7350 378 379 135 8400 412 413 135 8450 463 464 135 8500 514 515 135 10600 616 617 135 12700 718 719 172 14800 820 821 172 17900 922 923 172 201000 1024 1025 172 201100 1126 1127 172 201200 1228 1229 172 201300 1330 1331 172 201400 1432 1433 172 201500 1534 1535 172 201600 1636 1637 172 201700 1738 1739 172 201800 1840 1841 172 201900 1942 1943 172 202000 2044 2045 172 202100 2146 2147 172 202200 2248 2249 172 202300 2350 2351 172 202400 2452 2453 172 202500 2554 2555 172 20

3 or 150mm wide coupling joint.31 For 175mm wide coupling joint.

30


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rr.NIIANTIT

2600 to3700 ContactAmiantit FIBERGL4SS for exactdimensions

8.2 Field Closure1. Carefully measure the space where the

closure pipe is to be placed. The closurepiece must be 50mm shorter than the lengthof the space. The piece must be centeredwith an equal clearance of 25mm leftbetween the inserted pipe and the adjacentones.

2. Use a special pipe with long machined endsordered or prepared specifically for thispurpose.

3. Else two double bell couplings without acenter register or two wide type flexiblesteel couplings.

4. Pull the couplings onto the machined endsof the closure pipe after lubricatingabundantly the ends and the rubber ring. Itmay be necessary to gently help the secondring over the chamfered end of the pipes.

5. Lubricate well the ends of the two adjacentpipes after they are cleaned thoroughly.6. Place the closure pipe in its final position

and pull the coupling over the adjacent pipesup to the home line (Figure 8.2. Steps 2 and3).

Note: After the coupling is in final position a"feeler" gauge maybe used to assure that gasketlips are properly oriented

0o . . _ _ - - - - ~ ~ l ~ - - - - - . - - . ~ n

0~ 0 03 c : x t r = = j ~Figure 8.2Closu re Section Assembly

__________________Amlanu1 ~ L . - 1FIBERGlASS 1 . . 1 " ~ ~- - -

31


33/43

c;..~ : " " ..,.. .. - ' ~. . . . . _ _ . , . . . ~ - - > .......... - ~ ~ "

..,.. -_,RI\II/ANTIT9 Post-Installation9.1 Checking the Installed PipeReg uiremen :

Maximum installed diametrical deflectionmust no t exceed the values in Table 9.1initially or long term. Bulges, flat areas, orother abrupt changes of pipe wall curvatureare not permitted. Pipes installed outside ofthese limitations may not perform asintended.

Checking to insure that the initialrequirements have been met is easy to do andshould be done for each pipe immediately aftercompletion of installation (typically within 24hours after reaching maximum cover).The expected initial pipe deflection isapproximately 2% for most installations at theTable 9.1Allowable Vertical Deflection(% of Diameter)

Nominal Pipe DiameterDN2:350mm

Maximum Allowable2

Initial Deflection 3.5% 3.25%Maximum Allowable

Long-Term Deflection 5.0%D N ~ 3 0 0 m m

Maximum AllowableInitial Deflection 2.5%

Maximum AllowableLong-Term Deflection 4.0%

Pipes installed with initial deflectionsexceeding the values in Table 9.1 must bereinstalled so the initial deflection is less thanthose values. See section, Correcting Over-Deflected Pipe, for limitations applicable to thiswork.

Procedure for checking the initial diametricaldeflection for installed pipes:l. Complete backfill ing to grade.

5.0%2

2.5%4.0%

- - - - - - - - - - - - - - - - ~AmianiU ..:.,;u4-1FIBERGlASS I J " ~ ~-maximum cover given in Table 4.4 and isprop01tionally less at shallower depths.Therefore, while initial deflections in Table 9.1are acceptable for the pipe performance, a valueexceeding the expected amount indicates theinstallation intended has not been achieved andshould be improved for future pipes Ci.e.increased pipe zone backfill compaction. coarsergrained pipe zone backtill materials. or widertrench. etc.).Deflection checks should be done when the firstinstalled pipes are backfilled to grade andcontinue periodically throughout the entireproject. Never let pipe laying get too far aheadbefore verifying the installation quality. This willpermit early detection and correction ofinadequate installation methods and keep to aminimum the number of inadequately installedpipes.

Native Soil Group3 4 5

3.0% 2.5% 2.0%5.0% 5.0% 5.0%

3 4 52.0% 1.5% 1.5%4.0% 4.0% 4.0%

2. Complete removal of temporary sheeting (i fused).3. Turn off the dewatering system (i f used).

4. Measure and record the pipes' verticaldiameter. Note: for small diameter pipes, adeflectometer or similar device may bepulled through the pipes to measure thevertical diameter.

5. Calculate vertical deflection:32


34/43

~\.,- >-=- ..- -. / ~ I A N T I TActual 10 - Installed Vertical 10

%Deflection = ------------Actual 10Actuall.D. maybe verified or detennined bymeasuring the diameters of a pipe not yetinstalled lying loose (no pipes stackedabove) on a reasonably plane surface.Calculate as follows:

Vertical J.D.+ Horizontal J.D.Actual I.D. = -----------2

I.D.(l) + I.D.(2)Actual I.D. = ------2

(See Figure 9.1 below).

Figure 9.1Determining Actual Pipe I.D. On Pipe Not Yet Installed

9.2 Correcting Over-Deflected PipePipes installed with initial diametricaldeflections exceeding the values in Table 9.1

must be corrected to insure the long-termperformance of the pipe.Procedure:For pipe deflected up to 8% of diameter:1. Excavate to a level equal to approximately85% ofthe pipe diameter. Excavation just

- - - - - - - - - - ~Amlanlu ~ \ o - 1FIBERGlASS I J " ~ ~--------------

above and at the sides of the pipe shouJd hedone utilizing hand tools to avoid impact ingthe pipe with heavy equipment (Figure 9.2).

2. Inspect the pipe for damage. Damaged pipeshould be repaired or replaced.

3. Re-compact haunch backfill, insuring it isnot contaminated with the native soil.4. Re-backfill the pipe zone in lifts with

appropriate material, compacting each layerto limit the pipe deflection.

5. Backfill to grade and check the pipedeflections to verify they have not exceededthe values in Table 9.1.

For pipe deflected greater than 8% pipediameter:1. Pipes with over 8% deflection shouJd be

replaced completely.

May beexcavatedby machine

Must beexcavatedwith hand tools

Must bere-compacted

Figure 9.2Excavating over-deflected pipe

9.3 Field Hydro-testing

JOOmm

Some job specifications require thecompleted pipe installation to be hydrostaticallytested prior to acceptance and service. This isgood practice as it can permit early detection andcorrection of some installation flaws, damagedproducts, etc. If a field hydro-test is specified, itmust be done regularly as installation proceeds.Installation should never exceed testing by more

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than IKm. In addition to routine care, normalprecautions and typical procedures used in thiswork, the following suggestions should be noted:1 Preparation Prior to Test:

Inspect the completed installation to assurethat all work has been finished properly. Ofcritical importance are:

a. Pipe deflection limited to the valuesin Table 9.1.b. Joints assembled correctly. Systemrestraints (i.e. thrust blocks. andother anchors) in place and properlycured.

c. Flange bolting torqued pe rinstructions.d. Backfilling completed. (It ispermissible to leave joints exposed ifthe line is restrained sufficiently toprevent movement).

e. Valves and pumps anchored.2. Filling the Line with Water- Open

valves and vents, so that all air isexpelled from the line during filling andavoid pressure surges.

3. Pressurize the line slowly. Considerableenergy is stored in a pipeline underpressure and this power should berespected.

4. Insure the gauge location will read thehighest line pressure or adjustaccordingly. Locations lower in the linewill have higher pressure due toadditional head.

5. Insure the maximum test pressure is notexceeded. (See Table 9.2.) This may bedangerous and result in damage to thepipe system.

6. If after a brief period for stabilization theline does not hold constant pressure,insure that thermal effect (a temperaturechange) or entrapped air is not the

__________________.Am1anlll ~ - . . . \FIBERGlASS U " " ~ ~-

cause32. lfthe pipe is determined to beleaking and the location is not readilyapparent, the following methods may aiddiscovery of the problem source:

a. Check flange and valve areas.b. Check line tap locations.c. Use sound detection equipment.d. Test the line in smaller segments

to isolate the leak.Table 9.2Maximum Field Test Pressure33, 34

PressureClass (K.Pa)I 00 (Gravity)300 (3 Bar)600 (6 Bar)900 (9 Bar)

1000 (10 Bar)1200 (12 Bar)1500 (15 Bar)1600 (16 Bar)1800 (18 Bar)2000 (20 Bar)2500 (25 Bar)3200 (32 Bar)

9.4 Field Joint Tester

Maximum FieldTest Pressure35 (KPa)

150450900135015001800225024002700300037504800

Portable hydraulic field joint test equipmentcan be supplied for diameters 700mm and above(see Figure 9.3).

This equipment can be used to internally testpipe joints prior to or after backfilling.Additional details are available from thesupplier's Field Service Representative.32 Amiantit FIBERGLASS pipe, being a glass-reinforcedpolyester pipe, will expand under pressure. Henceadditional water will be required to make up for thisexpansion.33 Refer to section 9.4 for alternative to the complete linefield hydro testing.34 Ensure thrust blocks are designed to resist the field testpressure with adequate safety factor.35 Pressure head difference between pressure gaugeelevation and the lowest pipe invert elevation (Bottom ofthe lowest point in the line) shall be added to the pressuregauge reading (lm elevation diffe rence= I 0 KPa).

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_Y4/VIIANTIT

Caution: Field Joint Tester is designed toa llow a test of the joint to verify that th e joint hasbeen assembled properly with gaskets in properposition. This equipment is limited to atmudmum pressme lest Level of 6 bars.Additional care shall be taken whe11 testing thejoint of a short pipe length to ensure the shottpipe develop adequate soil resjstance to preventsliding.

' "".4nl1alllll.FIBERGlASS < J " y , _ i ; . . ~

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9.5 Field Air TestAn alternate leak test for gravity pipesystems may be conducted with air pressureinstead of water. In addition to routine carenormal precautions, and typical procedures,usedin this work, the following suggestions andcriteria should be noted:

1. As with the hydro-test, the line should betested in small segments, usually the pipecontained between adjacent manholes.

2. Assure the pipeline and all laterals, stubs,accesses, drops, etc. are adequately cappedor plugged and braced against the internalpressure.3. Slowly pressurize the system to 24kPa. Thepressure must he regulated to prevent overpressurization (maximum 35kPa).4. Allow the air temperature to stabilize forseveral minutes while maintaining thepressure at 24kPa.5. During this stabilization period, it is

advisable to check all plugged and cappedoutlets with a soap solution to detectleakage. If leakage is found at anyconnection, release the system pressure, sealthe leaky cap(s) or plug(s) and begin theprocedure again at Step 3.

-------fD.Amlanu1 ~ l . . o lFIBERGlASS I J " )L . l . .H------------------

6. After the stabilization period, adjust the airpressure to 24kPa and shut-offor disconnectthe air supply.

7. The pipe system passes this test if thepressure drop is 3.5kPa or less during thetime periods given in Table 9.3.Caution: Considerable potential energy is storedin a pipeline under pressure. This is particularlytrue when air (even at low pressures) is the testmedium. Take great care to be sure the pipelineis adequately restrained at changes in linedirection.Table 9.3Test Tame- Field Air Test

Dia. Time Dia. Time(mm) (min.) (mm) (min.)80 2 800 20100 2Y, 900 22Y,ISO 3% 1000 25200 5 1100 27Y,250 6'!. 1200 30300 7% 1300 32Y,350 8% 1400 35400 10 1500 37Y,450 llY, 1600 40500 12Y, 1800 45550 14 2000 50600 15 2200 55700 17Y, 2500 60800 20

8. Should the section of line under test fail theair test acceptance requirements, thepneumatic plugs can he coupled fairly closetogether and moved up or down the line,repeating the air test at each location, untilthe leak is found. This leak location methodis very accurate, pinpointing the location ofthe leak to within one or two meters. Consequently, the area that must be excavated tomake repairs is minimized, resulting inlower repair costs and considerable savedtime.

Note:1. This test will determine the rate at which airunder pressure escapes from an isolatedsection of the pipeline. It is suited to

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determine the presence or absence of pipedamage and/or improperly assembled joints.

2. This test is not intended to indicate waterleakage limits. If he pipeline fai ls this air test ,it should not be rejected until a hydro-test iscoaducted.

!RI< 1 , ~ w r . . U I ~ ..... olFIBERGLASS . _ r ) A _ _ _ . C . . ~

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Appendix AApproximate Weights of Pipes and Couplings36Nominal PiJ!e \ K ~ m } WeightDiameter STIS STIS STIS STIS Per(mm) 1250 2500 5000 10000 CouplingK 37

80100 2.5 2150 5 3200 7.5 4250 11 6300 15 10350 13 16 18 12400 15 19 22 13500 23 29 33 17600 32 41 46 21700 42 54 62 26800 53 70 80 31900 67 88 101 361000 82 108 123 421200 117 153 176 541400 158 207 238 681600 204 268 3091800 256 337 3892000 316 416 417

2500 470Appendix B

Joint Lubricant Requirements

NominalPipe Diameter (mm)80 to 300350 to 600600 to 800900 to 10001100 to 12001300 to 14001500 to 16001800200022002500

Nominal AmountOf Lubricant (Kg)Required per Joint

0.050.0750.1000.1500.2000.2500.3000.3500.4000.4500.550

36 For sizes not covered, contact Amiu11tit FIBERGLASS.37 Coupling weight may vary depending on the couplingpressure class.

';___J.Aml.ti\IIJ q ~ o - 1iFIBERGlASS 1 . 1 " ~ ~~

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Appendix CNative Soil Groups (Classification)Native soils are classified into five main groups,ranging from very stable dense granular soils andrelatively hard cohesive soils to relatively poororganic and fine-grained soils. The soil groupsare a function of both soil types (classification)and soil density, which together determines themodulus of the soil and its ability to support thepipe and backfill material. Relative quantificationof densities may be determined from blowcounts38 measurements as given in Table Cl. Theblow counts must represent the most severe(weakest conditions expected to exist for anysignificant period of time. (Normally thiscondition occurs when the water table is at itshighest elevation).Group 1 -Very Stable SoilslA - Dense (per Table Cl) gravels or sands,

according to ASTM D248739 GW, GP, SWand SP containing less than 5% fines(orATV Type I).

lB - Hard or very stiff cohesive soils as perTable CJ.

Group 2 - Stable SoilslA- Medium consistency per (Table Cl ) slightlysilty or clayey gravels or sands, according to

ASTM D2487 GM, GC, SM and SCcontaining less than 15% fines (or ATVType 2).

lB - Stiff cohesive soils as per Table Cl .

38 Blows are measured with 50mm (2in) OD; 35mm (1 3/8in) sampler driven 305mm (I ft) by 63.5 Kg (140 lb)hammer falling 762mm (30 in). See Standard Method ForPenetration Test and Split-Barrel Sampling of Soils (SPT)ASTMD1586.39 "Standard Test Method for Classification ofSoils For Engineering Purposes".

- - - - - - - - - - - - - - - - ~.AmlanU1 ~ l o o lfiBERGlASS i J " ' ~ ~----------------

Group 3 - Soil Mixtures (Medium Soils)Typically medium consistency cohesiveand/or loose granular soils, (per Table CI),according to ASTM D2487 ML or CL withliquid limit less than 50 and GM, GC, SMand SC (or ATV Type 3).

Group 4 - Cohesive Soil (Poor Soils)Soft and very loose consistency soils (perTable CJ), according to ASTM D2487 MH,CH, OLand OH (or ATV Ty pe 4).

Group 5 - Very Poor SoilsVery Soft and very loose consistency soils(per Table Cl), according to ASTM D2487MH, CH, OL and OH. These soils are of fthe ATV scale for soil quality.

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.......... .. ...- -I A N T I T

Table C1Native Soil Group Classification

SoiJ Groupobesive40(Fine Grained)

Granular011(Coar e Grained)Blow Counts

Table C2

Very Stable1Hard orVery tiff

Very Den e>30

Stable2

StiffDense16-30

Soil Mixtures(Medium)3MediumMedium

6-15

__________________Am1anlll ~ \ . o - 1FIBERGLASS 1 . 1 " ~ ~------------------

Cohesive Soils(Poor) Very Poor5of t Very oft

Loose Very Loose3-5 0-3

Simple Field Test for Determining Soil Group42Soil Group Measurable Characteristic

1 Can barely penetrate to readily penet rate with thumbnail2 Can barely penetrate with thumb3 Can penetrate to 50mm with thumb with significant effort4 Can easily penetrate 50mm with thumb5 Can penetrate with moderate effort SOmm with fist

40 Soils containing a large portion of fine particles (clay and colloidal size). Shear strength is already or entirety derived fromcohesion (natural attraction ofparticles). Includes clays, silty clays and clays mixed with sand or gravel.41 Soils not exhibiting natural particle attraction. Shear strength is mostly related to compactness (density) of the confinedgrains. Includes sand, gravel, cobbles, stones, etc.42 Peck, Hanson and Thombum, Foundation Engineen'ng, 2nd ed., John Wiley and Sons, Inc., 1974.

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Appendix DSoil Characterist ics

ConsistencyVery SoftSoftMediumStiff

Very StiffHard

CompactnessVery LooseLoose

MediumDenseVery Dense

Blows44 Per305 mm (ft)(No.)0-23-56-1516-30

31-50>50

~ mwll1l ~ ~ . , < \FIBERGlASS I . I " ) L . l : . ~------------------Cohesive Soilsqu45

( K N / m Identification Characteristics

0 to 25 Sample tends to lose shape under own weight26 to 50 Molded with slight finger pressure51 to 150 Molded with moderate finger pressure151 to 300 Molded with substantial finger pressure

Molded with substantial finger pressure Not301 to 500 molded by finger pressure ; requires pickingto remove>500 Difficult to remove by picking

Granular SoilsBlows Per Relative Moist Unit Weight305 mm (ft) Density (KN/m3)No.0-5 0 to 15% 11-166-15 16 to 40% 14-18

16-20 41 to 65% 17-2031-50 66to 85% 18-22>50 >85% 20-23

43 Soils containing a large portion of fine particles (clay and colloidal size). Shear strength is largely or entirely derived fromcohesion (natural attraction of particles). Includes clays, silty clays and clays mixed with sand or gravel.44 Blows are measured with 50mm (2in) OD; 35mm (I 3/8 in) sampler driven 305mm ( l ft) by 63.5 Kg (140 lb) hammerfalling 762rnm (30 in). See Standard Method For Penetration Test and Split-Barrel Sampling of Soils (SPT) ASTM Dl586.45 Unconfined compressive strength.46 Soils not exhibiting natural particle attraction. Shear strength is mostly related to compactness (density) of the confinedgrains. Includes sand, gravel, cobbles, stones, etc.41


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