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    A P P L I C A T I C N S I M f L A R I T V P R I N C I P L E S AND

    TUR ULENCE RESEARCH TC BED LOAD M O V E M E N T

    by

    Dr . Ing. A. Shields

    T r a ns l a t e d f rom:

    Anwendung d e r Aehnlich keitsm echa nilr und

    der Turbulenzforschung a d die

    Geschiebe

    bewegung Mittei lungen d e r Pr eu ss is ch en

    Vers uch san sta l t fu r Nassexbau nd Schif fbau,

    Ber l in ,

    1936

    by W I? Ott and J C van U chelen

    Soil. Conservat ion Serv

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    n~Ove~ ken2n P V & ~aze 1 inadequ.a@s nce:t~Bedgeo

    the

    procaeees,

    and 23

    the

    caavoidable

    maek

    5 ~a:rnxiaaity a ^ ~ I Q ~ .qerimLcnt;3,

    eo

    bad-loa&

    xckovezmeat n

    r ivers, Mor,;vever, they-

    -wad. not cover

    LPP

    bed-isad

    prob1e:ms e n c o ~ ~ a t a r e dn hydrauA.ie en gins aria^^

    $+* oreover, he ux~avstsidabls

    - C l

    aec nd

    aec+Loa

    caneiders p r i ~ ~ ~ a ~ ~ ~

    zle

    c s k ~ d ~ ~ ~ s n e

    t

    he

    be-

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    finds

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     n &i %. i i~rm

    l osev

    t&e e

    25

    xist only

    the f.r.i&iou

    f o ~ c c a

    pressure ,Qarcca

    re@nl%%ng%ozfi he ~ d ~ i ~ h tf&be%.water,

    ~o n s e y a e n t l y , he

    eonaponent

    of

    the weigh5 in the

    direction 0 E f k v ~

    a s t

    e

    equated to the total

    slxeax*upon

    the

    perimeter::

    with smaL1

    d

    sin c:-- tzwg@ slope,

    -asregarding the fPicdtioa

    o

    air , nd v~rikfng:

    &.eaf%agstress

    ; an

    a : ~ e b a ~ @ d

    -+;erthe

    -wetted

    peri:me&er, As

    a ru le -

    this

    a

    momentum

    r ~ ~ e $e applied

    to the

    bottom s folPows:

    bottom nd

    perpendfeu1a.f

    zo t11e

    i s ~ v e ; ~

    f he s t ream

    Fig

    2

    shows

    the

    subdi~sion l

    yeas.

    fnee

    khc

    .si 3,g

    areas

    cu9

    the iso~sels e-:peneicu%ar, there a r c c

    shearing fopecs yaa . s fe r~edlona these asreas,

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    What rex~-mias

    a

    e

    de'kesmia&l

    age thb2 oubdivisiiandl areas ad Aw.

    f vv~s igae isn

    a - -

    of a

    series

    - f

    isa\*ebs

    shows -ih la

    composite

    cross-

    [email protected];iLh

    pc r i r ~e teb -a

    f u ~ i l o ~ p ~z irreg 4a.r

    ~ o u g b r ~ e s s ,

    ~ h., re

    vd

     a

     l

    1

    d ~

    .e

    05

    [see --age

    6

    nd

    J-

    page

    10)

    a

    desired

    a.9;.p.zi.oxbr?~;a;ee

    =&

    di%4s%ors%el:e ercas..seegion

    can

    agt;incd

    y ~ - ~ ~ ~ ~ ~fmiddle and

    arSgL~Ear

    division Ilne

    a ,

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    k e r

    *. --

    B + , % u ~ , . 1- a t e of . a - the computed sub-

    n

    &visiana*l vo.e~scf$-Jes,

    rhesa esmpu&aionsare

    ~a> It,ed..e h 0 ~ 8 M8f Z O V ~ P ,

    eince t S J

    ~

    qtzc.rfisn ~ ~ h c t h e ~

    o ap~ibicat ian

    6

    the

    resui ts o

    cir~ul:? :r.-

    ---

    COW &~$

    elq~eri:msnb

    s p:~ rn , fsible c,r

    the

    sub,divisional

    cross

    s e ~ f f n ~n

    q ~ ~ e ~ t ~ , ~ a ,t advi.sable to

    exnreae

    the

    mean

    part-ve5oeities in relation to

    the

    cross .~ec&iona,i loci&v,

    s n c e ;

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    B rs%rativc ~aghaess ~s v ~ c l lsa g;4her f a a c e ~ ~ s ,

    $ ~ ~ V ~ ~ . _ V C F .o

    res&

    gcaz;raS

    cancluaiolln,

    is

    ~ + e e e s a ~ r y-hat

    he

    q u ~ n t i l y - disc%-a&rgee a aawin3uim va:uc .

    SJ- a

    the latter being an a ~ ~ t ~ - a o i . a fequisi te, F s z a

    h ~ % ~ L e d g e

    f

    the processes

    involved,

    vcPocity

    mmacaur

    emants

    a r e

    necae

    sr

    in order

    tea

    eonstruet

    t he

    isoval

    patterns.

    On he ather hand, since the canstruetion s complete

    i ~ 6 v e I ateern requires Baborio~~s

    ork

    and

    i s agtte.cnunnecessary,

    t

    i s

    more przetics%to d e t e r r ~ i n e portion sf' be pattern,

    Measurements n MI

    open

    channel

    '8.Sitere

    arried sut in the follo\z~%ng

    anner:

    A Pitot tube v ~ a , ~Eaced upon a kzidge in

    such a

    n ~ a r n e r ha h tube

    could

    be

    moved horizantafiy across in he ci~a-mef,

    A perpendicular velocity

    as t r ibut ion

    n

    %e

    m i d d l e

    Bane

    vvas

    next

    recorded,

    order

    to

    deter ldnc

    ta what wid & the uelocitiaa of he

    zor,e: ecxtsnd~d, he Pitot tube wao

    %en gradually .r;-.,o~~edcross the chanael ,

    In this -aanner

    the

    region of

    validity his

    V~IOC~ ~;-

    .

    s ributBon

    W ~ I

    e8kabE8 ds

    Thereupon

    tsac~:'17e

    farce

    axqd r n i . 8 ~

    scloeiPf

    w e r 8

    graphically

    dete~x:ained,

    ebis region

    also

    being dzciaive for bed-load.

    I T I O V ~ ~ ~ ~ E ~ ~

    The value

    5 tbe tractive X Q P ~ ka th i s region

    was

    determined by She

    level

    of

    he -maximum

    vz,scitg,

    As

    Lsng

    as

    ekis

    i%23.~~-mern

    velocity

    was

    main-

    tained

    at

    the

    s~~.rt%acz,t

    w a g

    pc~ssfbfe O UPC the ~i iaiter epth fn t h i ~ O % ~ ~ U -

    lation, Up to he

    t ime

    the bed was

    cxees~ i vc2y

    ev:delsged, re-cxaminatisa

    of

    the tractive force swsa pss sx i i ka ace no ~4laence as exercised

    by

    the

    UI

    vta14is, and the km:bBfez~e

    COU

    d.eveIop freeky, n a m

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    siace

    P=Til:uza2se',

    veluc;: A : E, 8

    ia

    v d i d

    8cg xalp*Per ta definite roughn ss

    ,

    (see Pn$luanre sf Grain 6&3,pe), A -- provided

    I 1s icx~ewn

    could

    be computed,

    This rcauPted i n A .- va ues

    -;thich

    z agprax J z:~oteiy, O C s~nalieria,~

    -a

    &

    d

    &%

    one

    p ~ ~ t & ~ ~ ~ gjf --- against

    Isg

    An

    the; g ~ k % c l ~ a l~'z$bb~.S,fngf

    the bed., due

    8 $e

    6

    - f s

    0

    d e w ~ ~ ~ p ~ ~ ~ . i . ~ t ~

    ~t :d

    e dete;:rnrrtea

    ~y gstanxatic

    dewiationa, The

    m a g ~ d t ~ d cfA $OX

    2h,e

    ~;esiaus kinds

    sf r ~ ~ ~ g h n c s s

    ith

    quadreABc resistance

    is

    given by a q u s & i ~ ~

    -i-3

    an6

    p

    gs

    4

    a~ x d

    5%ll,u&zz te tine

    pi3Miag

    0 2 u

    agaiaat y a

    logarithmic

    f t9rm

    * 9

    far

    variaus wszar d-.pt::l.,s W P G ~c m~ ta r~ tiope,

    6

    Hz obvious that the

    friction

    Ip

    this

    geckiwfi

    t

    jz s

    been

    S ~ B Q - ~ ~ P ; ~

    &i,yc,*j

    j e

    sh,ear

    ~ - n &

    s s ~ h & ~ g e

    & a

    e

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    .

    --

    ~ ~ ~ ~ f d e ~ i n g

    he

    grad3 s

    k~:

    ;s

    bad

    ~ f

    ~;r.~~~.rcr:::~~

    5:~~~j.n

    f.aes

    tpbc

    q ac:gtion

    is .---

    v , ?&~a&

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    reppase. Lsa d e c i 3 i ~ ~ ezain area {i h

    -again

    d e p e ~ d i z g

    olely up n ~ n c

    -

    grain

    shape

    [ a

    / x ~

    n&icates tb, stagp-ation

    pressure

    o

    a

    crktieal

    e

    veIocieJj l

    :zin. shape ),

    ~ y c 2 ~ 2 e R 8 y v L

    I-irb eC.eqc..i3'ia.:iduL5.td~ecief;.'i.cient 2 the grain depends

    upon both,

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      ourth regicn, \:J;~:~

    gre~kex*s*-d k~

    alues th t

    i s

    cgioa

    i 17

    iP

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    q - 5 8 balds ir8pap ;

    u]ar

    for

    e w

    -..-

    --A .

    ,J.&,A ~.ne,,~si t sh ooting f3.o~~

    since

    4

    al.1 s

    Iacae \yJaF@

    ?:i

    oQf;

    i , e -v~ith

    amka,'Jl

    depths,

    of

    njovercank

    sf m2zrtarL:t,

    E.P

    paaBPq

    x i s c ~ 0 ~?iasiciiiik~rf:y 2 the

    gsaia

    a>apes,

    i

    sav9, ,'* vbr. ..rp 3 P

    *=,,*

    t :

    *,,

    ; ~ c c g ~ ~ L c . A I BetaLai,~ .3ii,

    bec use rixjs .TI

    he

    nand ~ K I ~ X ~ U ~ Se , ~~~;* rxs - ;

    9

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    8 i n e ~

    >-- i s also valid fo r the inyrestigate4 type of broavn

    coal

    %

    '3

    bed

    loadAi,

    w e can

    210:

    the c o r r r s p o n d i ~ ~ goints in Fig. 6.

    The

    obvious

    h

    odorm mi ;^,,

    together w$th

    Lkc conformity of barite

    and granite bed laad

    .

    =

    ere he b r o v ~ n

    exeeg.:

    the

    separat io:~

    nd

    cornenLnkisn o

    f iner parzs lead to a sanirnewhat l%i@hercritical

    i w, . A ~ Z G ~ ~

    ---P-~-e ---.p

    urnishes

    e-vidsnce

    that the influence sf iweigkt upon t he

    beginning sf

    haa bean

    ftelly

    covered,

    Influence

    o

    Grain

    Sbape

    -1Pw

    The

    grain.

    shape

    Tray

    i n i i u c ~ c e

    he beginning

    af

    movement

    in

    just as

    many

    respeces as tbc

    -~ai.al=aeq

    ;ppe:-as-ing

    in derivszisns of the aqusa kiongar

    ha b eg i n a l ~ ~ g%~xoxren~ent ,

    hey

    we.+e

    ae follov~s:

    = in6Buence

    of

    grain

    shape

    upan p~%r $rsi ty

    P

    d z

    =

    ixifluznce of grain shape upor. bed- i r ic i iua

    coefficient

    @

     

    i ~ f l u z n c e

    f grain

    shaglie

    u p ~ n

    r a i n

    surface

    3

    Pa4 .Ge:r?rasses influence of grain s i ~ a p e pon

    flow

    cond ik io~s n

    l t is evident

    from. Fig,

    6 $haitthese

    131,

    s a y

    elczrt opposing in -

    rounded

    gr~a ins nd s h a ~ p - e d g e d r s i ~ sie

    sor12ewl1.,at

    higher

    than

    those

    f o r

    grain shape garan:etritaEly,

    In

    eat:er lo

    llu&rw& thie

    point,

    @

    muat

    investigated

    eeparatzPy,

    The

    g ~ r o s i t ~

    ,

    :an

    be 2asiI.y dekt~1~~4fLi~$d,

    I

    +

    q may

    'p 6siblg

    be

    d i t ~ r a l ~ n e d

    y ~ r ? ~ i ~ r e i ~ ;

    at is,

    by

    s-irt,usring

    a ew

    - .

    erains on a beard

    wli &-~

    i3i i forzm.

    +rsdna g;.iled an do IE* thzn

    b y g r a d ~ ~ a l l y

    n

    = k*

    #

    clining the bsrArd vhile si-$?&l$ sl~a-icin.~j$;

    4@sz~*&~~nding

    ~rbultgia $ZCI~~tu-

    &e$cas),

    un.tjl

    the g2:ains

    3-s)iil

    of;,

    xfi

    &f

    manne$f

    ~ g i $ i @ a l

    l ~ p e

    e

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    used

    by

    Cdsey,

    ix:,?gi:ther

    % t i k d r ~ & %

    ap ith he^^

    ;lave

    zk:-,aJa

    experit1~1.?n$c

    n ; ,?~s

    v i t i a aagular grai12.3 I ~ Q : X J ~ % ~ ~ F

    q2eti'~ 1-tez.7r@9rl cbp x? c$aanncls

    * i ~ l ~ 5 : 1

    granite

    f d i1gzxentsof

    ar sh8-r.m ( t y ~ , ~

    -3 IT? -;$ittiv e r y sharp edges

    were

    avail-

    slbe

    to

    clea.2

    u

    :=his

    point,

    To

    deskzr~mj-neefinitely

    he

    nfluence

    of

    the

    grain shape requires

    that

    all

    ather

    variables mechanical. m d hydrhulic .-

    - *

    be ekim-icated,

    k c ~ a r ~ n g l p ,

    he axpe5.rncnts \

    it11 gzanite gr ,~in- t yes

    ere

    made not only v ~ i t ? - ~hs s ~ x r ~ enif~>:~n-i~ a i n

    i zes {d -.

    0 , 8 5 mm, d -- 1-23mm,

    d =

    %,44

    nxx and in same channel, bat also with

    be

    same slopes, and by

    using the sams ewperiixeatsl technique as

    sad

    by Gasey in his

    s a r ~ d xperime~:ts~

    rzle ~iftzsuj. . fa:: grain sjzeg 3,

    g 5

    ;m3yI a2.ltl

    2,44 3 3s

    Eire

    very

    cl-.,dractzr-

    i ~ t i c

    ;mid

    85 j3

    d s p i& b

    i g s u 9 and

    lii:

    > f

    3

    pja'kted agdas t f ie ,

    il?ustri*';ion ehaivs ti2ni

    kc

    -values fo r

    the

    meny-edged gj:.;iils iie every

    t ime

    about

    ten

    pe:- ;.zent higher than hose

    Isx

    rounded sends

    - i

    e,

    n

    awguls-z

    qrsie~ ;.o&~~,ces

    p2a t e s c

    ~ I O ~ J Y

    uesistzt~ee&aa

    z-ounde2 one, Thus he --a

    * A h n

    velocity,

    wit;. constar& 5 ,

    i a

    es w i t 3 fr g ~ ~ e n t a

    b a . wit

    sand,

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    ff3Pnxaeio -' eel rLc ~ ~ s s U ~ &~asgi.::~@ ys oon :eache& Tl~tas,

    ba

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    The

    3eroistenee 0. He

    type

    oi

    moEfau

    and Lhe t i m e required for

    %t.sith

    a

    miovable bed this

    3criad

    indicates

    he

    pcrtiaeng

    sea , for

    bed-

    3.4

    Bsad ~mo ~ezx3.,ebfs. ,ee

    Krey

    t i m e scale

    ?OF thzt e~z;>zripn~nd9

    1 : ; h

    a t ~ a i g k t hannc ,

    Eowevcr

    results

    ob%&ned

    i~itk

    -~i:fe~Trne~t&.Z

    h a ~ a , z h areish

    vahsbfe

    facts

    {barn-i,%g

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    P*S;

    inus

    i r o ~ ;

    i ~ e ebd-tivc

    ~ ~ ~ , . g 4 n c s s ,-:l~ce ,pa.~ii~bHe~re

    a be

    considered:

    P PL

    1

    sne born?

    of

    the *&~ataauzface

    2,

    Tbe

    w a t e r

    depth

    3

    The bed

    shape

    A t the

    present

    state

    61 seier t2Ae

    i avea t ig~~t iont s practical&

    *

    iwlpossihte

    0

    Saifi 3

    a?&,a,-

    c*zy~f~ens--en&sn6

    one

    a*L.,us ie

    oetisfied

    w i t h

    csas ide~ai ion be ?

    shape

    w: ..rdvpa ep

    dep &*

    It

    ~ ~ f i c e s

    o design&%@%e

    bed sh pe

    xaerely by the

    relation

    oi

    -

    heigkk

    to length,

    nd

    0%

    bed

    de~fe lsp~~e, r irsegulas:i&ies

    d

    LQe

    b~etow-,

    k CC c

    d

    thi

    s

    &he

    extent

    ~ e d

    de-:re%oprfie: ;:&Ci

    3~Hichs 2

    -.sq;.rea

    sed

    sLwmeneisn-.

    l e s ~ l y

    y

    the relation

    of the

    hsEgh4 0%

    he

    ripples, dx..x~es,xe S OUT

    holes to

    the w a t e r

    de;:-&,

    &J'a

    &p$l2e:c &e

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    TL

    s s a ~ ~ e z * -he

    gs&n matzraa i ,

    tnt

    y :

    2~&%9:jccn

    eiabt

    e2

    an.d

    %eae&$

    of

    bed

    f s ~ ~ ~ ~ ~ i o n

    ecpaeese~, ,.r>&e a fire

    sarF,e

    E fi2e -

    as

    s h o ~ l in

    iT

    g , 6 -

    the

    r31am3er

    0 ed-load

    r~~ovemze:18h a ~ ~ g e s

    n

    the fo elox:ring

    sequeaee:

    scaLe3,

    g & ~ r ~ ~ ~ ~ ~ ~ ,

    ~ y q

    ze,- ~

    (f?:eq:ao-&H.br of &;2liqnz sl~.aupe)ntil

    -~j&eahe

    oalace v,

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    &*

    8 -

    ? +

    IT d

    #

    ,""*

    *---

      ~ S and s k a ~ ~ e

    ac&aps

    nd

    ally

    ccsm~?,a?~t$sa

    K

    >rp

    "

    these raagaitudsa

    rs analysi s pro~dsl;

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    ..-.

    I1 pp

    7 ;th

    st ll

    i;rijates

    I{ l

    -*>a] also for b =

    ; : S ~ . Q Q

    coal i s

    t rausgressed.

    vev y

    ngjl

    v ~ B U C : ~

    T- f ff,,-

    _.y di g E ~ ~ Ffii~..

    ~ f i l g

    b e smbes. hesl~kts

    O 1 1 . 6

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     -a  

    pee i g z

    c

    n

    Grain .m

    q gh

    6 ~

    *'* -?* Zq

    u

    s,dv~2d,3~a~~6. aa

    diam.e er &~pe

    y 7 ex

    >-

    : &- a

    VJ ?

    I L ~ ~ ~ z

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    Fi g . 1

    F i g .

    2

    F i g . 3 Rat io of hydraul ic ra d iu s to

    dep th

    a s

    funct ion of depth width ra t io .

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    Fig .

    4.

    Veloci ty d is t r ibut ion

    c u r v e s f o r B a r i t e .

    d 1 .52rnm S 1/500

    Fig. 5. Velocity distr ibuti on

    c u r v e s f o r B a r i t e .

    d

    2. .?6mm

    S

    1/380

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    Fig.

    6 .

    Trac t ive fo r ce coeff i ci en t

    Y ,

    Y)d

    a g a i n s t t h e

    V4cd

    Reynolds numb er of the gra in

    Fig .

    7. C r i t i c a l tr a c t i v e f o r c e r aga ins t we igh t

    of

    g r a i n l a y e r s ,

    y

    y d ,

    the c u r v e s re ob ta ined f r om F ig . 6 a s s u m i n g

    =

    0.012 a n d =

    1) .

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    Fig 8

    Cumulat ive mechanical

    ana ly s i s cu rve and modulus

    M

    Af /A c of a bed m at er ia l

    Fig 10 Res is tance coeff ic ient a s a funct ion

    of the Reynolds nu mb er

    Fig 11 Ge om etri c si m il ar i ty of two sta tes of flow

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    Fig .

    15.

    Plo t of e m pi r ic al equat ion fo r

    bed- load t ranspor ta t ion .

    Fig.

    16

    Sieve ana lys i s squ a re mesh ) .

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