14
Review Comprehensive review of structural deterioration of water mains: physically based models Balvant Rajani * , Yehuda Kleiner Institute for Research in Construction, National Research Council Canada, Ottawa, Ont., Canada K1A 0R6 Received 14 July 2000; received in revised form 30 March 2001; accepted 11 May 2001 Abstract This paper provides a comprehensive although not exhaustive) overview of the physical/mechanical models that have been developed to improve the understanding of the structural performance of water mains. Several components have to be considered in modelling this structural behaviour. The residual structural capacity of water mains is aected by material deterioration due to environmental and operational conditions as well as quality of manufacturing and installation. This residual structural capacity is subjected to external and internal loads exerted by the soil pressure, trac loading, frost loads, operational pressure and third party interference. Some models address only one or a few of the numerous components of the physical process that lead to breakage, while others attempt to take a more comprehensive approach. Initial eorts were aimed mainly towards development of deter- ministic models, while more recent models use a probabilistic approach to deal with uncertainties in de®ning the deterioration and failure processes. The physical/mechanical models were classi®ed into two classes: deterministic and probabilistic models. The eect of temperature on pipe breakage is discussed from three angles; the ®rst deals with temperature eects on pipe-soil interaction, the second deals with frost load eects and the third provides a brief review of various attempts to statistically quantify in¯uence of temperature on water main failure. This paper complements the companion paper ``Comprehensive review of structural deterioration of water mains: statistical models'', which reviews statistical methods that explain, quantify and predict pipe breakage or structural failures of water mains. Crown Copyright Ó 2001 Published by Elsevier Science Ltd. All rights reserved. Keywords: Deterministic; Frost load; Physically based models; Probabilistic; Structural deterioration; Temperature eects; Water main failure 1. Introduction The physical mechanisms that lead to pipe breakage are often very complex and not completely understood. These physical mechanisms involve three principal as- pects: a) pipe structural properties, material type, pipe- soil interaction, and quality of installation; b) internal loads due to operational pressure and external loads due to soil overburden, trac loads, frost loads and third party interference; and c) material deterioration due largely to the external and internal chemical, bio- chemical and electro-chemical environment. The struc- tural behaviour of buried pipes is fairly well understood except for issues like frost loads and how material de- terioration aects structural behaviour and perfor- mance. Consequently, extensive eorts have been applied to model the physical processes of the degra- dation and failure of buried pipes. As discussed in the companion paper, more than two- thirds of all existing water pipes are metallic about 48% cast iron and 19% ductile iron). From the 1880s to the early 1930s, grey cast iron pipes were manufactured by pouring molten cast iron in upright sand moulds placed in a pit. These pipes were known as pit cast iron. In 1920s/1930s a new manufacturing process was intro- duced in which pipes were horizontally cast in moulds made of sand or metal that spun as the moulds were cooled externally with water. These pipes were known as spun cast iron, which had better material uniformity than their predecessors, with corresponding improve- ments in material properties. In 1948, the composition of the iron was changed to produce what is known as ductile iron pipe, which was more ductile and less prone to graphitisation. However, industrial production of ductile iron pipe did not begin until the late 1960s. By 1982, virtually all new iron pipes were ductile iron. Urban Water 3 2001) 151±164 www.elsevier.com/locate/urbwat * Corresponding author. Tel.: +1-613-993-3810; fax: +1-613-954- 5984. E-mail address: [email protected] B. Rajani). 1462-0758/01/$ - see front matter. Crown Copyright Ó 2001 Published by Elsevier Science Ltd. All rights reserved. PII: S 1 4 6 2 - 0 7 5 8 0 1 ) 0 0 0 3 2 - 2

6 PIPING

Embed Size (px)

DESCRIPTION

6 PIPING

Citation preview

  • !"""# $" % !""# % !""

    & C40( )* +

    ( , -

    ( , & .

    / ( , &

    ) )

    0 (

    , -

    1(

    1 , 2 . 3

    4(

    , & +

    4

    , & .

    1(

    (# 4

    . 3

    . / 5

    ,

    & 66

    77 ) / 1( ,

    ( !"" 8 9 - :, ; ( ,

    & 1( )

    ,& 3 C40* 3

    / # C40*

    ) 0 # C40* ( ) 3 3 , & 3

    )

    1 3 . 3, / ) .

    (3 ,

    ;

    3 )( C40 ?@ A@ *, = ??" A$" ( ( ( , & 1 , 2A!"+A$" (

    3 B ) , & 1

    ( 3 , 2 A? ( 1

    (, C ( AD", A?! ,

    E > $ C40!""* FGD

    ,,++

    ( , &, H3D$3AA$3$?"# ) H3D$3AF3

    FA?,

    ,I, C40, *,

    D!3"JF?+"+K 3 , ( !"" 8 9 - :, ; ( ,822 - D ! 3 " J F ? C40 " * " " " $ ! 3 !

  • & ) 3

    (

    (

    , & ( ( ( 66(77, L3 1 ( 51

    , 9

    ( 1, & (4 3 , =

    ( 3 ) , &

    ( . ( ( , -

    ,& .

    ( ,(, C

    )3( 1 , ( ,

    & (3 8M 8M 3 $FG"

    , & 3 ( ) (

    C40

  • !,! ( , - $

    , 9. 1( .

    - F, & 1( (3

    ( . 1( ,

    * / 0 0 &

    * 1 2 0, & ( 1( /

    ( 3 ) ,, , & ( ) ) (, P C40AAD* P C40AAJ*

    , & 3

    &"

    &

    .

    3 B

    B( 14G .

    3 3

    / 5

    ,

    2 / . 14 3 14G , & . 14 .

    B( .

    14G ( , & 14 (

    =(, !, (

    ,

    =(, , = C40* (

    5) C40*

    C40*,

    ! " # $ %& ' ( C40*+ ,-. F$

  • ( ( 3 )

    ,4, & 3

    ( 3 (( , & )

    ,;( 4 / (4 , &

    4 (3 ( ( ,5 4 , & /

    B( ) 14 (( B

    ( B( , &

    (( 14 3 3 (( ) ( (3(, & ( B( 1

    4 4(, & ( ) / ( 3 ,

    ** 60 2 0, & 3

    0 7 3, -( C40A*

    ( 3 5)

    ( , >1 -( C40AF?*

    , &

    / (

    (

    )

    ( 5 ( C40,(,

    0 ,*, & 3

    D

    $ !$ !

    !

    0 ( 0

    1

    5 0 3

    ( 5

    14 ( . ( ,

    P 1 C40AAD* 3

    7 3

    ( )

    (, & 3

    )

    )

    ! $ $

    ) ( 8 8

    0

    )

    3 . 1

    G

    ! $ 3 ,

    & ( 3

    1

    , ; 8M ) )

    3 B, & ) 3 C40,(, N L A?F* (

    ( 1 ( ( , & (

    1

    ((,& ) 3

    1( 3

    , & B 14

    ( ( .

    , 3

    1 P C40AAD* , C40AAD* ( 4 8M 9 ,4, & -(G>1 3 3

    33 1 ( 3

    , & 3 3 ( /

    , % 5 (

    -(G>31 , & ( , C40AAD*

    F ! " # $ %& ' ( C40*+ ,-.

  • . ) / 3

    1

    , C

    ( ) 3

    / 1(, & 3 ) 3 ( (

    1 ,5 4 , & /

    ) G , & 3

    (

    5 ) ) , 2

    ( ( 3 ,

    *( 2 0, &

    3 ( ;-%9+;Q-2$L C40AA*, & 33 )

    , : MC40A?A*

    "

    F

    "

    )

    3

    ( ( ) (

    ( ) (

    1

    (2 = ((

    ,4, &

    ( , &(( C40 = * , -

    , &

    (

    ( 1,

    & / 3

    , &

    ( ( 1 (, & ( ( ( ( 1 / 3 , 2 (

    ( ) , 3/ / (

    (

    , 2

    ( ( ( / ,5 4 , & /

    3

    , (

    3

    /

    ( ,2 0, %1 %

  • **

    8

    2 0, %1 -(C40A?*

    ) C40-2* 3

    ,;( -2 ( ( C40 4* 4, & -2 (

    -2 "" ""

    J

    (

    1

    ,

    > -2 "" 3(

    J"@ ( 1

    -2 $", &

    ( )

    /",J, = (

    ( 3 ( ), & -2 $",&

    ( 661 77 ( -2 ( ( C ( 1 ( . ,;( 3

    C405

    *

    4 ( .

    , O -2 $" 4

    1

    , , C40A?* 1 ( 4

    1

    , & ) 1 3

    , ; 1(66877 / ( ( ,4, &

    4

    3)

    3

    ( ( 4

    1

    / 1, , C40A?* ( ,&

    C40ADA* ( , 2 ( /

    , = ) ",F? ( C40",JG",F* C40,(,

    ADA*, & ) 1

    ( 4

    1

    1 -. LC40A?!*, ; )

    1( C40/ 4

    1* ) , Q 66(

    477

    ,5 4 , 2

    / ( G 1

    3 G 3 C 4

    1 C40 *,

    2 0,

  • , = C40) * 9/, C40?*

    C40ADA* ) ( , 2 ) ( ( , & 0 >;+;Q-2 "3DJ AJJ* ) 4

    ,(, ) ,5 4 , & /

    (

    ( C , & )3 4 ,2 0, 3-

    O3

    C40AA!* 3

    (

    C40

    *

    ( ,

    "

    ( (

    1

    ( ) ,

    & ( ( 1, 2 ( 3

    3 ( ( ) ( B

    ( 1 ( 3

    ,

    (

    ( (

    ( , 2

    9/, C40"* ( ) , & (3 ( / ( 66 77,4, &

    /, &

    )

    ( 1 )

    . , &

    (

    , C 3

    )

    / 1

    , & 3

    (

    ( , - 3( 3

    (, = )

    3(

    ( ,5 4 , & / (

    1

    )

    (

    , & )

    , ; (

    3

    / (

    3

    ,2 0, %1 C40!"""* 3

    ( ( ( ( (

    , & 4 66 77 (

    , & (

    3

    ) ( 3

    , & 9/, C40* C40$* C40* C40D* C40?* C40A*,

  • =(, , 8 %1 C40!"""*,

    =(, $, 8+ ,

    F? ! " # $ %& ' ( C40*+ ,-.

  • & (

    ( ( 1 3 C40Q1 3 3 (

    , ! = 1

    9/, C40!* 5

    1

    : (

    3

    , & / 3

    ( , 9 3

    1 , ; 3 ) 3

    , -/ ) 3 C40 * 3 , ; ( 5 3

    , & 5 ( C40* 3 , 2 / ; %

    C40AAF* ) 1( 5 (

    , :13( )

    ( , &

    1( ) 34,4, & ;

    %

    C40AA AAF* 1 ,& (

    ( ,& 33 4

    3 ) , & 3 ) ,& .

    -(G>1 3 3

    ! &

    ( 5

    ; %

    C40AA*,

    ! " # $ %& ' ( C40*+ ,-. FA

  • , & )3

    C403* ( 0 3

    (

    ,=

    ( 5 (43, & 1( ( 5 ( , 2 Q; ( (

    ,5 4 , & /

    / -(G>1 3 3

    3

    , & C40 * / , % )3

    , -

    , 2 ) 3

    1

    %3 , & %3 ( 4 ( 3 3) ,2 0, -

    ,(, C( C40AAJ AA?* C40AAJ*:1 - C40AA?* 8 C40AA?* - C40AA*

    ( (( M C40A?A*, &

    ( 3

    5 ,

    8 C40AA?* ( 1 (

    , & 3

    ( (/ ( ,

    C( C40AAJ* (( C40* ( ( " C409/, C40F** ) (3 , C( C40AA?* )

    3 (

    ( (

    (

    , & )

    , C %1

    ( 3 3, & 3

    C40

    * , & ( B( ,O (

    ,4, & 1

    ; %

    C40AA AAF*

    ( (( M C40A?A*,-

    3

    , C3

    3( ) 1 ( 3

    ( ( 3 /, & ( (

    (4 ( ,5 4 , & /

    ( 1

    )3

    ( , ; 3 /

    ( 3 )( ( 4

    ,2 0, EQ 3

    ( (

    (

    9E, ;( CB , C40!"""* 3 / ( , & ( 1 /

    ( 3 , -4 EQ

    . / 4 /,C 3 ,(, B =3 C40AAD AAA* (

    ( ,

    &

    %1 C40!"""*,

    D" ! " # $ %& ' ( C40*+ ,-.

  • &

    C40 * 0 1(

    (

    ( C40 * )

    ( (

    ( )

    0 ( C40( *) ) (

    , &

    ,C40A?* ; %

    C40AA*, & 3 + 1 34 , & %3 3 ) / , &

    ,

    =

    + EQ

    1 %1 C40!"""* =(, ,

    & . 1( , >1 8 C40A?!* (( 1( (

    ) ( , & 1

    1(

    ( 3(

    (

    " (# " 1 1

    # ; ( # , &

    / 1( ,

    Q C40A?* 1( -3&> ;, C 1(

    (3 C40

    B( ) Q ; )3

    (3* , C 1( ,,

    1(

    ) 1( , C

    3

    1( C40 1 3(3* 4

    ) , C 66(77

    1 ( , Q C40A?*

    AJ" AJJ ( C40

    0 ",A* 3 1 3 (3 (

    &

    !F & ( F"" !

    9/, C40!* - -3 & (

    4, & (( ( !,F1 F"@ ) )

    (3, Q

    1 ( ) (,

    C C40AA* >( C40

  • (3# ( Q C40A?*

    , Q 1

    ,

    - - P( C40AAA* 43 1 C40;QQ* 3 9 , & ;QQ 1 ( C40 * C40 *

    (

    1

    , - 1 ( ( ((3 , & 1 3

    3 F" D

    , ;

    3(

    , &

    ( ;QQ 6677 1( , $

    & ;QQ 1 3( , ; ( 1 / , & 1 J3 , & / 3 (3 ( , & 5 3 /, 2 (( 3 ( 1 / ( ,

    & ;QQ (

    1, 2 ( ) 3 3

    1( , 2

    , ;( 3

    C40 )* ( , 2 1

    ( 1 0, =3 1(

    ) , > 1(

    ;QQ ( , = ( / ,

    & 1 ( ) , & ( 3 / /

    , 8( 3 /

    , &

    /3

    ( ,

    & + (

    , & ) ) / 5

    ( (

    , & +

    (

    , & 4 ) / 1(

    ,

    & +

    1( /

    / 4, -

    ( 1(

    , &

    4 3( 1

    , & (

    , & 1(

    ,

    & ( ( , ; )3

    3

    .( 1( 1( C40(

    *, C

    $ 2 ;QQ 663

    77 ( 66(77

    ( ( (

    ,

    D! ! " # $ %& ' ( C40*+ ,-.

  • (

    /, 2

    (

    / / , &

    , % / ( ( ,

    !"

    &

    ) E( > 2 :, C40E>2*