study of stresses & strains in cylindrical cement silos-project proposal

7/23/2019 STUDY OF STRESSES & STRAINS IN CYLINDRICAL CEMENT SILOS-Project Proposal

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STUDY OF STRESSES & STRAINS IN CYLINDRICAL

CEMENT SILOS

By

E/08/039 BANDARA N.V.A.S

E/08/087 GAMAGE H.G.N.S.

E/08/323 SILVA W.G.S.W.

Su!"#$%! '(

)"*+. ).B.R. D$%%,-,(,!

Project No: C/08/08

Department of Civil EngineeringFaculty of Engineering

University of Peraeniya

Peraeniya !0"00

#ri $an%a

Fe&ruary !0'(



ABSTRACT

)all structures containing materials suc* as grains an cement are usually calle silos+ ,any failures

occurre in cylinrical silos ue to t*e lac% of unerstaning of stress an strain &e*avior of silo -alls+

)*is researc* is to stuy an analy.e stresses an strains in t*e -alls of cylinrical cement silos ue to

t*e store material -it* aisymmetric loaing an unloaing process+ n finally valiate/evelop t*e

eisting e1uation or efine t*e ne- e1uation for t*e stress in t*e silo -all+ Finally t*e eisting

relations*ips for pressure variations on silo -alls -ill &e valiate -it* appropriate moifications+

2



ACNOWLEDGEMENTS

2e -oul li%e to give our special t*an%s to t*e Department of Civil Engineering3 Faculty of

Engineering3 University of Peraeniya for giving us t*is opportunity to o a researc* project in our

acaemic course+ 4ur special t*an%ing goes to Prof+ P+ B+ 5+ Dissanaya%e-*o is t*e supervisor of our

project3 for *is guiance+

2e also li%e to t*an% Dr+ P+B+6+ Dissanaya%e an Dr+ 7+ 5+ B+ erat* -*o are t*e panel staff of our

project for giving a goo contri&ution to ma%e it a success+

Finally -e -oul li%e to t*an% Eng+ + ,+ + C+ #+ Banara 3instructors an tec*nical staff in t*e

structure la& for t*eir continuous support+

'9/0!/!0'(

Banara N+++#

6amage +6+N+#

#ilva 2+6+#+2

3



TABLE OF CONTENTS

);)$E++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++i

B#)5C)+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ii

C7N42$ED6E,EN)#++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++iii

)B$E 4F C4N)EN)#++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++iv

$;#) 4F F;6U5E#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++vi

$;#) 4F )B$E#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++vii

$;#) 4F BB5E;);4N#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++viii

C*apter ' ;N)54DUC);4N++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++'

'+' Bac%groun+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++'

'+! 4&jectives++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++!

'+( #cope 4f )*e #tuy++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++!

C*apter ! $;)E5)U5E 5E;E2+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++(

!+' ;ntrouction+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++(

!+! Bul% ,aterial Pressure++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++"

!+!+' ;nirect ,et*o+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++"

!+!+! Direct ,et*o+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++8

!+( cting loas on silo construction+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++'0

!+" Determination of safety for t*e silo structure+++++++++++++++++++++++++++++++++++++++++++++++++++++++++'0

C*apter ( ,E)4D4$46<+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++''

(+' option ' = test -it* prototype++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++''

(+! option ! = test -it* Cement silo in 6alle++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++'!

4



(+( Compare eisting e1uations++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++'!

C*apter " )5;$ )E#)++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++'(

"+' pparatus++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++'(

"+! Proceure+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++'(

"+( 4&servation+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++'"

"+" Calculations an 5esults+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++'>

"+> Develop )*e Finite Element ,oel for t*e ume Pipe++++++++++++++++++++++++++++++++++++++++++++'9

"+9 Comments on results+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++'?

2457 #CEDU$E++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++'8

C4#) E#);,);4N+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++'@

5EFE5ENCE#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++!0

5



LIST OF FIGURES

Figure '+': ie-s of silos !

Figure !+': #ection of t*e cement silo ?

Figure (+': Comparison of pressure ue to European Coe @

Figure "+': rrangement of t*e apparatus '!

Figure "+!: Crac% pattern in *ume pipe '>

Figure "+(: ariation of #train Ae '>

Figure "+": ariation of e -it* time '>

Figure "+>: FE, of *ume pipe '9

6



LIST OF TABLES

)a&le '+': ariation of e values -it* time '"

7



LIST OF ABBREVIATIONS

FE, Finite Element ,et*o

P Pac%ing ouse

8



CHA)TER INTRODUCTION

Containers use for storing &ul% solis are usually calle &ins3 &un%ers3 silos3 or tan%s+ Bins or Bun%ers

are s*allo- structures containing coal3 co%e3 ore3 crus*e stone3 gravel an similar materials+ But

mostly a silo is a tall cylinrical structure containing 6rain or Cement+ ,ost of t*e cases t*ese #ilo

structures are commonly use for store Cements+

#ilos are mostly are mae &y steel or reinforce concrete+ )*ere are lots of Cement silos t*at

are mae &y reinforce concrete+ ,ost of silos are constructe on mat or pille founations+

#ometimes #ilos coul &e elevate an supporte &y frames or reinforce concrete columns+ )*e

esign of a silo is normally epen on t*e type an t*e property of t*e fille material+ )*is structure is

loa carrying system is ifferent from t*e normal &uiling structures+ )*ere for t*ese #ilos are

esigne an evaluate as special structures+ Currently3 t*e C; ('( ocument AC; '@@? is t*e

-iely use guieline pu&lis*e in t*e Unite #tates for t*e esign an construction of #ilos+!

. BACGROUND

For ealing -it* a real silo -e selecte t*e cement silos of t*e olcim cement factory3 6alle t*at -ere

esigne in '@9! &y Danalit* a/s3 Copen*agen an F+$+ #mit* G Co+ $t+3 $onon for Ceylon

Cement Corporation3 Colom&o+ )*e factory3 incluing four cement silos -as commissione in '@9?+

)*ese cement silos -*ic* are "> years ol3 are still in use+

)*ese " cylinrical silos3 eac* -it* a *eig*t of (0+"m an eternal iameter of '0+0m3 are &uilt on

pile founations+ Cement is pumpe into all " silos from t*e top regulate &y valves fie in mac*ine

c*am&ers locate at t*e top Aelevation is at !9+!m from t*e top of founation of eac* silo+ ll "

mac*ine c*am&ers are connecte &y reinforce concrete passages at t*at same elevation+ ccess to t*e

mac*ine rooms is provie t*roug* a &rige constructe &et-een silo = " an t*e pac%ing *ouse AP

-*ic* is t*e ajacent &uiling+ )*e &ottom of eac* silo is slope Anot visi&le from t*e outsie+ Cement

t*at comes o-n along t*ese slopes is t*en pumpe into t*e P t*roug* pipes regulate at " ot*er

mac*ine rooms locate at t*e groun level+ )*ese mac*ine rooms are also connecte t*roug* a

reinforce concrete passage+ vie- of t*e four silos is given in Figure '+'+

1



F$1u"! . V$!% *+ %$4*%

.2 OB5ECTIVES

aliate/evelop t*e eisting relations*ips or efine moifications to t*e eisting relations*ips for

stresses in t*e silo -all+

.3 SCO)E OF THE STUDY

#tuy an analy.e t*e stress an strain in t*e -alls of a cylinrical silo ue to t*e store material -it*

aisymmetric loaing an unloaing process+

2



CHA)TER 2 LITERATURE REVIEW

2. INTRODUCTION

#ilo failure is a p*enomenon -*ic* *appens &ecause of t*e lac% unerstans of its &e*avior+ #o itHs

very important to get an iea a&out t*e silo failures to unerstan t*em+ #ilo fail -it* a fre1uency

-*ic* is muc* *ig*er t*an ot*er inustrial structures+ ;f some silo fails it is cause to financial loss as

-ell as loss of life also+ #ilo failures can &e occurre in t-o -ays+

• Dramatic structural collapse AComplete failure

• Non ramatic structural collapse

)*e major causes of silo failures are t*e s*ortcomings of t*e follo-ing four categories+

• Design

• Construction

• Usage

• ,aintenance

2.. F,$4u"!% u! 6* !%$1- !""*"%

;n esigns esigner s*oul *ave consiere non uniform loas3 t*ermal loas3 effect of nonstanarfa&rication etails an etc+ n also special attention s*oul &e given to *o- t*e most critical etails in

t*e structure -ill &e constructe+ )*ere are five most common pro&lems -*ic* esigners often ignore

are given &elo-+

• Bening of circular -alls cause &y eccentric -it*ra-als+

• $arge or nonsymmetric pressure cause &y inserts+

• ;gnoring flo- patterns an material properties+

• Non consieration of temperature an moisture effects+

2..2 F,$4u"!% u! 6* *-%6"u6$*- !""*"%.

Construction is one of t*e main processes t*at irectly cause to failures+ Construction failures can &e

occurre ue to t*e follo-ing t-o reasons+

• Poor -or%mans*ip+

• Faulty construction+

3



)*ese construction errors can &e categori.e in t*ree ifferent -ays+

• ;ncorrect material+

• Uneven founation settlement+

• Design c*anges in construction+

2..3 F,$4u"!% u! 6* u%,1!

Normally structures are esign for a certain esign+ But &ecause of incorrect usage t*e service life of

t*e structure reuces+ For eample3 some pro&lems can &e raise -*en t*e flo- properties of t*e

material c*ange+ ;f ifferent material is place in a silo t*an t*e materials for -*ic* it *as &een

esigne+ )*at may &e a reason for failures+ )*ese failures can &e categori.e into t*ree sections+

• Dynamic loas ue to collapsing arc*es or rat*oles3 selfinuce vi&rations or eplosions+

• C*anges in flo- patterns+

• Buc%ling of unsupporte -alls+

2.. F,$4u"!% u! 6* $"*!" ,$-6!-,-!

,aintenance is a major re1uirement for every structure+ ,aintenance *elps %eeping a structure *ealt*y

for a longer service life+ #ome of t*e pro&lems ue to improper maintenances are given &elo-+

• Corrosion an erosion+

• $ac% of routine inspection+

• ;mproper reaction to signs of istress+'

2.2 BUL MATERIAL )RESSURE)*e static pressure inuce &y a store material on a silo -all is t*e most important component3 -*ic*

may also inclue ynamic forces &ecause of loaing or unloaing3 t*ermal effects3 an seismic or

-in+ )o etermine &ul% material pressure t-o met*os can &e use+

2.2.1 I-$"!6 M!6:*

)*e inirect met*o consists of etermining t*e strains in t*e silo structure3 for eample on t*e

concrete surface or on t*e *oop reinforcing+ But o&taine in t*is -ay t*e tensile strains are very

ifficult to interpret in vie- of t*ermal3 ynamic influence+ #everal researc*es

4



-or%s -ere carrie out &y several researc* groups to stuy t*is area+

2.2.. 5,-%%!-;% <89=> %$4* 6:!*"( ,- $6% !#!4*!-6%

IanssenHs A'8@> silo t*eory *as constitute t*e &asis of silo esign for many ecaes+ )*is t*eory

accounts for t*earc*ing effect -it*in t*e &ul% solis an allo-s for transfer of part of t*eir -eig*t to

t*e -all in s*ear -*ere it is carrie to t*e &ase of t*e silo as -all t*rust+ ;t suggests t*at t*e *ori.ontal

pressure P may &e esta&lis*e as

PJγ sr [1−exp (−2 Kμy /r )]

2 μ '

P ori.ontal Pressure

ɤs Unit 2eig*t 4f #tore ,aterial

r 5aius 4f )*e #ilo

y Dept* ,easure From )*e )op 4f )*e #ilo

Friction Coefficient Bet-een #tore ,aterial n ertical 2all

K Friction ngle

7 5atio Bet-een ori.ontal n ertical Pressure APv/P*

7 is t*e ratio of mean *ori.ontalto mean vertical pressures3 assume e1ual to t*e 5an%ineHs coefficient

of static eart* pressure Ae+g+3 6urfin%el '@?@L6aylor an 6aylor '@8":

K =1−sin∅

1+sin∅ !

2*ere ∅ is t*e angle of internal friction+ Eperimental stuieson eep silos carrie out &y Pieper

an 2en.el A'@9"reveale t*at IanssenHs silo t*eory coul lea to &etter results &y calculating t*e

coefficient 7 as

K =1−sin∅ (

Furt*ermore3 Briassoulis A'@@' reporte t*at many investigators Ae+g+3 Co-in '@?@L Da&ro-s%i '@8>

*a s*o-n analytically t*at 7 may &e &oune &y

1−sin∅

1+sin∅

< K <1

"

5



an t*erefore e1+ ! merely represents a lo-er &oun for t*e pressure ratio 7+5otter A'@@0 s*o-e

t*at a more realistic value of 7 can &e erive from t*e relation first introuce &y 2al%er A'@99 as

K =

1+sin2∅−2√ sin

2∅− μs

2cos

2∅

4 μs2+cos

2∅ >

)*e values of 7 estimate from e1uations+ ! an > iffer only slig*tly unless t*e -all is

consiera&ly roug* A5otter '@@0+"

2.2..2 M!6:* ,% "**%! '( S*:",'u$- A:,? M. A4,u$-? @$, W,u<2003>

Conventional analysis of silos for stresses istri&ution cannot preict all t*e stress resultants re1uire

for silo esign+ )raitional met*os also cannot efficiently incorporate effects of lateral force ue to

-in+ #o*ra&uin *ma3 ,+ lauin an Mia 2au *ave carrie out an etensive parametric

stuy &ase on finite element analysis of structures+ )*e met*o propose &y t*em gives all possi&le

forces an moments re1uire for t*e esign of t*e silo an consiere various support systems an

loaing conitions3 incluing -in effect+ 9

ear t*ey *ave consiere t*ree loa cases3

'+ #elf-eig*t3 consiere aisymmetric

!+ #tore material pressure3 consiere aisymmetric

(+ 2in loa3 consiere nonaisymmetric

n also t-o parts of silo *ave &een consiere separately3'+ Conical *opper

!+ ertical -all

Parameters consiere in t*e parametric stuy

• eig*t of vertical -all3

• ;nternal iameter of silo3 D

• )*ic%ness of vertical -all at &ottom3 ) &ottom

• )*ic%ness of conical *opper at top3 )top

6



• Dept* of ring &eam3

• ;nclination of conical *opper3

• eig*t of *opper &ottom a&ove flo- level3 *O

• Unit -eig*t3

• ngle of internal friction3 Q

• Coefficient of -all friction3 O

F$1u"! 2.S!6$*- *+ 6:! !!-6 %$4*

#o*ra&uin *ma3 ,+ lauin an Mia 2au moele an analy.e a circular silo &y finite

element met*o using aisymmetric s*ell elements an &asis of t*e parametric stuy3 it *as &een foun

t*at t*e meriional an circumferential moments *ave significant values an it is suggeste t*at t*ese

&e consiere in esign+

,aimum stress resultant Aper foot of t*e element J R7+f '+f !+f (+f "++++++++++f n

ear3 % a is numeric constant an f '+f !+f (+f "++++++++++f n are multiplying factors+ ,ultiplying factors -*ic*

are relevant to t*eir researc* are s*o-n &elo-+

7



,aimum oopAnegative Forces in t*e ertical 2all ue to ,aterial Pressure

k -1273f 1 1+0.0071(H-39.6)0.827

f 2 1+0.0583(D-10)1.916

f 3 1+0.0226(α-40)1.014

f 4 1f 5 1+0.0392(Tbottom-6)1.053

f 6 1+0.0243(d-24)0.732

f 7 1+0.0285(γ-35)f 8 1+0.008(ρ-15)1.311

F9 1-0.8723(μ’-0.2)0.511

,aimum oop Acompressive Forces in t*e ertical 2all ue to #elf 2eig*t

k -868f 1 1+0.0061(H-39.6)0.968

f 2 1+0.0204(D-10)1.220

f 3 1+0.0140(α-40)0.794

f 4 1+0.0393(Tto-4)1.002

f 5 1+0.0145(Tbottom-6)0.811

f 6 1+0.0375(Tto-6)0.972

f 7 1+0.01609(Tbottom-6)1.004

f 8 0.9638+0.000223!d-36"1.658

2.2.2 D$"!6 M!6:*

)*e irect met*o -as &ase on pneumatic3 ynamometer3 &one -ire strain gauge magneto

elasticity sensors+ )*e formula for *ori.ontal pressure ue to store material is given &y3>

Ph=α ∗γ s∗ D

Ph ori.ontal pressure

D iameter γ s specific -eig*t of store material

α Comparisons of coefficient

Comparisons of coefficient α for t*ese measure materials ue European Coe are presente

in follo-ing figure+

8



F$1u"! 3.C*,"$%*- *+ "!%%u"! u! 6* Eu"*!,- C*!=

9



2.3 LOADS ACTING ON SILO CONSTRUCTION

#6S5 6 o# MJ 5 6 #6T0

#6 AComponents of loas loas acting against silo construction Ac*aracteri.e &y 5 63

,aterial pressure ph3

Pressure of aeration an *omogeni.ation3

)emperature graient across t*e silo -all )3

)emperature fiel on t*e silo -all cause &y storage grain T 3

;nsolation an aily temperature variation3

Displacement cause &y s*rin%age3

$oas cause &y post tensions3

4t*er as concentrate loas3A suc* as patc* loaings3

$oas cause &y eccentricity of isc*arging material etc+

5 6 AComponents of strengt* #trengt* of silo construction is c*aracteri.e &y suc* parameters suc* as:

stell an concrete3 strengt*3 cover3 iameter of &ars3 1uantity of reinforce *ori.ontal an

vertical &ars3 a*esion of &ars to concrete3 1uality of lap splices3 type an 1uality of -all

strengt*ening3 openings in t*e silo -all3 imperfections3 crac%s3 conition of &ars ta%ing into

account corrosion3 tec*nical conition of concrete3 i+e+ car&oni.ation3 etc+

2. DETERMINATION OF SAFETY FOR THE SILO STRUCTURE

#6J∑iAtmi#i3%

5 6J∑iAγmi5 i3%

tmi loa factor

mi are resistance factor

#i3% components of loas of silo construction

5 i3% components of strengt* of silo construction

%#6% S5 6%

#6 =multi componential action effects3

5 6 =resistance

10



% #ignificant c*aracteristic values+

6lo&al safety factorῶ

11



CHA)TER 3 METHODOLOGY

3. O)TION TEST WITH )ROTOTY)E

3.. D!#!4*$-1 A )"*6*6(!

prototype s*oul &e evelope using concrete3 plastic etc+ n it s*oul &e a&le to s*o- strain

variation for small loas+ )*is prototype -ill &e use to ientify stress an strain istri&ution of t*e

silo+

3..2 L*, T:! )"*6*6(!

First of all t*e prototype s*oul &e valiate+ For t*at uniformly istri&ute loa -ill &e applie along

t*e outer surface+ n t*e strain gauges -ill &e fie on t*e outer surface+ Using t*ose strain ata t*e

stress -ill &e calculate+

3..3 D!#!4* T:! F$-$6! E4!!-6 M*!4 +*" "*6*6(!

Finite element moel -ill &e evelope an it -ill &e valiate using a&ove calculate stress+

linear finite element moel is to &e one -it* #P !000+

• t first3 FE, moeling is one accoring to t*e imension an properties foun &y earlier+

• )*in s*ell elements -ill &e use to moel t*e prototype+

• )*e moel -ill &e analy.e -it* t*e loaing com&ination -*ic* -as use in t*e loa testing

an run t*e moel

• )*e FE, -ill &e compare results -it* t*e o&serve eperimental results

• Necessary c*anges -ill &e one to t*e moel until t*e eperimental an t*eoretical results are

almost e1ual+

fter t*at t*is valiate moel of t*e prototype -ill &e use for our future tests+

3.. T!%6$-1 T:! )"*6*6(! W$6: V,"$*u% M,6!"$,4%

Prototype -ill &e teste for t*e strain &y loaing various materials+ For t*at #train gauges an loa

cells -ill &e use+

12



3.2 O)TION 2 TEST WITH CEMENT SILOS IN GALLE

For t*is met*o t*e cement silos at Volcim Cement Factory3 6alleH -ill &e use instea of t*e

prototype+

3.2. L*,$-1 6:! S$4*

)*e silo -ill &e loae using t*e cement an t*e strain -ill &e measure &y using t*e strain gauges an

t*e ata logger+

3.2.2 D!#!4* F$-$6! E4!!-6 M*!4

Finite element moel -ill &e evelope an it -ill &e use to compare t*e e1uations an t*e test

results+

3.3 COM)ARING EISTING RELATIONSHI)S

;n t*ese &ot* options3 t*e values o&taine from t*e test results -ill &e compare -it* t*e finite element

moel results o&taine -it* various relations*ips escri&e in section !+! an !+(+ )*en t*e comments

-ill &e one on t*ose relations*ips an valiate/moify t*e eisting relations*ips or introuce t*e ne-

e1uations t*at are appropriate+

13



CHA)TER TRIAL TEST

<DETERMINATION OF STRESS STRAIN DISTRIBUTION IN A HUME )I)E DUE TO A

LATERAL LOAD>

,ainly t*is test -as conucte to ientify t*e stress an strain variation in a cylinrical *ume pipe ue

to lateral force+ )*e etermination of strains -as one &y placing strain gauges on t*e *ume pipe an

calculating stresses using t*ose strain values+

. A))ARATUS

• #train gauges

• Data logger

• Compression testing mac*ine

• erniercalliper

• 5uler

.2 )ROCEDURE

)*e *ume pipe -as carefully centere on t*e lo-er plate+ #urface of t*e *ume pipe t*at strain gauges

-ere fie -as cleane properly using a san paper to get a proper contact &et-een strain gauges an

surface+ ;n t*is case t-o strain gauges -ere use to o&tain vertical an *ori.ontal strains+ #train gauges

A6auge' to measure vertical strains3 6auge! to measure *ori.ontal strains -ere fie on t*e outer

surface of t*e *ume pipe at mile of t*e *ume pipe+ #train gauges -ere connecte to t*e computer

t*roug* t*e ata logger+ )*e loa -as applie t*roug* a steel ;&eam to give an e1ually istri&ute

lateral force on t*e *ume pipe+ )*e loa -as applie -it*out s*oc% continuously at a certain rate until

&rea%ing t*e *ume pipe an strain ata -ere recore in t*e computer+

14

61.83mm

2480mm

880mm #train gauges

6auge'

6auge!



F$1u"! . A"",-1!!-6 *+ 6:! ,,",6u%

.3 OBSERVATION

pplie loa -*en *ume pipe &rea%s J (>%N

T,'4! . V,"$,6$*- *+ ! #,4u!% $6: 6$!

T&m'(m) '-Ho#&*oto, '-'#t&/,

1 53.7738 77.358810 45.2832 66.981420 50.0002 72.6418

30 51.887 74.528640 47.17 69.8116

50 39.6228 63.207860 47.17 74.528670 51.887 82.0758180 40.5662 75.47290 36.7926 79.24561100 50.9436 108.491

110 52.8304 116.9816120 51.887 127.359

130 54.7172 164.1516140 68.8682 128.3024150 21.6982 93.3966

160 6.6038 111.3212170 5.6604 109.4344180 -14.151 78.3022190 -10.3774 67.9248200 -8.4906 67.9248210 -3.7736 72.6418

15

Crack starts

from outer side

Crack starts

from inner side

F$1u"! .2 C", ,66!"- $- :u! $!



F$1u"! .3 V,"$,6$*- *+ S6",$- <!>

16



. CALCULATIONS AND RESULTS

0 50 100 150 200 250

0

50

100

150

200

Time/(ms)

!V!"6$4!

0 50 100 150 200 250-20

0

20

40

60

80

100

120

Time/(ms)

!H*"$*-6,4

,aimum *ori.ontal stress3 W J EXAemaeinitiaX'09

J !9000XA'0! "?X'09

J '+"(0 N/mm!

,aimum verticle stress3 W J EXAemaeinitiaX'09

J !9000XA'?> ?(X'09

J !+9>! N/mm!

.= DEVELO)ING THE FINITE ELEMENT MODEL FOR THE HUME )I)E

Finite element moel -as evelope to compare FE, results -it* a&ove calculate stress+

linear finite element moel -as one -it* #P !000+

• t first3 FE, moeling -as one accoring to t*e imension an properties+

• )*in s*ell element -as use to moel t*e *ume pipe+

• )*e moel -as analy.e -it* t*e loaing com&ination -*ic* -as use in t*e loa testing an

running t*e moel+

• )*e FE, results -ere compare -it* t*e o&serve eperimental results+

17

1u"! . V,"$,6$*- *+ ! $6: 6$!



F$1u"! .= FEM *+ :u! $!

ccoring to FE,

ori.ontal stress3 W J 0+(@? N/mm!

verticle stress3 W J '+@>" N/mm

!

. COMMENTS ON RESULTS

)*ere is a &ig ifference &et-een t*e FE, results an t*e eperimental results+ Concrete is not a

totally elastic material+ ;t *as t*e plastic region too+ #o -*en t*e crac% occurs it *as passe t*e elastic

region+ But t*e #P!000 analy.e t*e moel &y assuming t*e elastic properties+ o-ever3 t*e actual

test -as one until failure -*ere t*e elastic region *as passe+ )*is may &e t*e closest reason for t*e

ifference of eperimental an moel preicte results+

18



WOR SCHEDULE

WORK 1 2 3 4 5 6 7 8 9 10 11 12

Develop a prototype

Load The Prototype

Develop The Finite

Element Model&

validate

Test The Prototype

With ario!s

Materials

"ompare e#istin$

e%!ations

Load the ilo in

'alle

Develop FiniteElement Model

"ompare e#istin$

e%!ations

Final report

19



COST ESTIMATION

t'm &t /t&t &t #&' #&'()

Hm' &' &t'm 1 16000 16000/d m3 1.5 2400 3600'm't &t'm 1 1000 1000't/, m3 0.25 2200 550 T#/o#t to :/,,' '# ;'/d 3 1000 3000 Tot/, 24150

20



REFERENCES

'+ Carson3 I+23 !000+ Silo failures: Case Histories and Lessons Learned. 4nline vaila&le at:

*ttp://---+inti+go&+ar/cirsoc/pf/silos/silofailures+pf ccesse '> Fe&ruary !0'(+

!+ em Dogangun3 Me%i 7araca3 *me Durmus an alil#e.en3 !00@+ Cause of Damage and

Failures in Silo Structures Iournal of Performance of Constructe Facilities3 ol+ !(3 No+ !3

pril '3 !00@+ Y#CE3;##N 088?(8!8/!00@/!9>=?'

(+ Prof+ pra 4ros.3 6yorgy Csato3 Ianos )amas%a3 Strengthning of a 2000 wagon capacity

reinforced concrete grain silo locate at marcali in Hungary. 4nline vaila&le at:

*ttp://fi&+&me+*u/ne-s/ci%%/v00ZenZfull/ci%%Z00en'0+*tm ccesse '> Fe&ruary !0'(+

"+ &elFatta*3)+,3 ,oore3;+D 3 &elFatta*3)+)3 !009+ Behaiour of eleated concrete silos

filled with saturated solids! 4nline vaila&le at:

*ttp://---+inti+go&+ar/cirsoc/pf/silos/&elFatta*Z,oore+pf ccesse '> Fe&ruary !0'(

>+ 7,;N#7;3,3 ,are% ,I3 !00@+ "#perimental and design loads of pressure of $ul%

materials against silo wall! Proceeings of t*e ;nternational ssociation for #*ell an #patial

#tructures A;## #ymposium !00@3 alencia Evolution an )rens in Design3 nalysis an

Construction of #*ell an #patial #tructures+

9+ *ma3#+3 lauin3, an 2au3+M3 !00(+ & Design 'ationale for circular Silos $ased on

finite element &nalysis! Iournal of Civil Engineering3 )*e ;nstitution of Engineers3 Banglaes*+

ol+ CE ('3No+ '3!00(+

http://www.inti.gob.ar/cirsoc/pdf/silos/silo-failures.pdf


http://fib.bme.hu/news/cikk/v00_en_full/cikk_00en-10.htm

http://www.inti.gob.ar/cirsoc/pdf/silos/AbdelFattah_Moore.pdf


http://fib.bme.hu/news/cikk/v00_en_full/cikk_00en-10.htm

http://www.inti.gob.ar/cirsoc/pdf/silos/AbdelFattah_Moore.pdf

study of stresses & strains in cylindrical cement silos-project proposal

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