Testing & Performance of Scc

8/8/2019 Testing & Performance of Scc

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Materials and Structures/Mat6riaux et Constructions, Vol. 33 , July2000, pp 391-397

Testing and performance of fiber-reinforced, self-consolidating concreteK. H. Khayat and Y. RousselUniversit~ de Sherbrooke, Sherbrooke, QC, Canada,J1K 2R 1

Paper received:June 9, 1999; Paper accepted: December 7, 1999A B S T R A C T R I~ S U M I~

The cas ting of f iber-re inforced concre te presentsgreater handling difficulty and requires more deliberateplanning and workmanship than conventional concretewit hou t fibers. Th e feasibility of prod ucin g fiber-rein-forced, self-consolidat ing concrete ( FR-SC C) that canbe cast into place with minimum or no consolidat ionwas inves tiga ted. Sixteen mixtures made wi th steelfibers measuring 38 mm in length used at dosages of 0,0.5, and 1%, by volum e, were investigated. The m ix-tures were prepared with various types of binary an dternary cement i t ious mater ial s and W/C M of 0 .37 to0.45. The higher W/ CM mixtures incorporated a vis-cosity-enha ncing agent to reduce the risk of segregation.Concrete mixtures with slump flow consistencies of 650and 530 mm were prepared, with the latter representinga highly flowable concrete that wo uld require some co n-solidation. Th e characteristics of these mixtu res werecomp ared to those of a conve ntional fiber-reinforcedconcrete with a targeted slump consistency of 200 mm.The mixtures were tes ted for rheologica l parametersusing a concrete viscometer, for restricted d eformabilityusing the filling capacity and V-funnel flow tests, as wellas for compressive strength and flexural toughness. Th epaper evaluates the suitability of using the above worka -bility tests to assess restricted deformability of FR -S CCand discusses the effect of fiber volume, m ixture prop or-tioning, and consistency on con crete properties.

1. INTRODUCTIONThe incorporation of steel fibers improves engineer-ing performance of structural and non-structural con-crete, including better crack resistance, ductility, and

toughness, as well as greater tensile strength, resistanceto fatigue, impact , blast loading, and abrasion. Th eincorporation of metallic fibers enhances the structuralpe r fo rm a nc e o f r e i n fo rc e d c onc re t e , i nc l ud i ng t he

L'utilisation de fibres m(talliques dans le bSton am(lioreplusieurs de ses caract&istiques. Cepend ant, les b&ons avecfibres sont plus difficiles a mettre en place et requi&ent doncune plan~'cation et une main-d'oeuvre plus importante. Lapossibilit~ de produire des b~tons autopla; ants renforc& defibres m~talliques q ui peuvent dtre mis en place avec peu oupas de consolidation a (t( &alu&. Seize m(langes de b&on,fairs avec des fibres d'acier de 38 mm de longueur a desdosages de O, 0, 5 et 1 ,0% en volume, out (t( confectionn&.Les m(langes out ( t( pr(pare's avec diff&ents types de lia ntbinaire et ternaire et un rapport E l L de 0, 37 a 0,45 . Lesb&ons want un plus haut rapport E/C contenaient un agentde viscosit8 pou r assurer la stabi lit( du m(lange. Des b(tonsautoplafants avec un (talement de 650 et 530 mm out (t~

fabriqu&. Les m(langes de b(ton de 530 mm d'&alement,tout en &an t tr}s Aquides requi~rent une & ergie de consolida-tion limit&. Les caract&istiques de ces m(langes out (t~ com-par&s a un b&on conventionnel avec fibres de 20 0 mmd' affaissement. La mesure des param&res rh&logiques a l' aided'u n rh&m~tre a b~ton a ~tS fait e, ainsi que la mesure de ladSformabilit( restreinte a l'aide de la capacit( de remplissage etdu test de l'entonnoir. De plus , la r&istance a la compressionainsi que la t&acit( h la fle xio n out (t( d&ermin&s. Cetarticle &alue la pertinet~ce de l'utilisation de ces essais pourobtenir la d(formabilit( restreinte des b&ons autoplafants avec

fibre s et discute de l'effet du volume de fibre , des proportionsdu m(lange et de la consistance sur les propri(te's du m~lange.

ii{{i!{iiiiiiiireduction of spalling of the cover over reinforcement inc o l umn e l e me nt s , t he i nc re a se i n she a r s t r e ng t h o fbeams, as well a.s the enh ance men t of ductility of beam -colum n connect ions. The use of fiber-reinforced con-crete ( FRC ) is also of special interest for retro fit and seis-mic design.

The incorporat ion of metal lic fibers can be problem -atic in some situations, especially wh en the fiber v olum eis high and the F RC is cast in sections with mod erate to

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M ater ia ls and St ructures /Mat6r iaux e t Const ruct ions ,Vol.33 , July2000

T a b l e 1 - M i x t u r e p r o p o r t i o n i n g o f th e 1 6 t e s t e d m i x t u re s ( k g / m 3)S e r i e s M i x t ur e s F i be r B i nde r Wa t e r S a nd C oa r s e W / C M H R WR V E A

c ont e nt a ggr e ga t e ( I / m 3 ) ( % wa t e r )A C O N V -O 0 4 0 1 ( 1 ) 1 7 1 9 0 6 9 6 8 0 . 4 3 4 . 0 0

C O N V -O . 5 3 8 3 9 3 ( 1 ) 1 7 0 8 8 6 9 4 7 0 . 4 3 4 . 0 0C O N V -1 7 7 3 9 6 ( 1 ) 1 7 0 8 9 3 9 5 5 0 . 4 3 7 . 5 0

B S C C -6 5 0 -V E A -O 0 5 5 4 ( 2 ) 2 3 1 6 9 4 8 6 7 0 . 4 2 4 . 1 0 . 1 8S C C -6 5 0- VE A - O .5 3 9 5 6 4 ( 2 ) 2 3 5 7 8 2 7 6 1 0 . 4 2 4 . 4 0 . 1 8

S C C -6 5 0 -V E A -1 8 1 5 7 9 ( 2 ) 2 5 7 7 9 1 7 6 4 0 . 4 5 6 . 3 0 . 0 2C S C C - 6 5 0 -0 0 5 2 9 ( 1 ) 1 9 9 8 6 7 8 1 6 0 . 3 8 6 . 0 0

S C C - 6 5 0 - 0 .5 3 8 5 3 3 ( 1 ) 1 9 6 9 0 6 7 6 2 0 . 3 7 7 . 0 0S C C - 6 5 0 -1 7 3 5 0 2 ( 1 ) 1 8 9 9 9 1 7 0 5 0 . 3 8 7 . 0 0

D S C C - 5 3 0 - 0 0 5 3 0 ( 1 ) 1 9 9 8 6 9 8 1 8 0 . 3 7 4 . 3 0S C C - 5 3 0 - 0 .5 3 6 5 0 4 ( 1 ) 1 9 0 9 1 0 7 6 4 0 . 3 8 6 . 8 0S C C - 5 3 0 -1 7 7 5 2 8 ( 1 ) 1 9 8 8 8 9 7 6 2 0 . 3 7 7 . 0 0

E 2 -S C C -6 5 0- VE A - O 0 5 4 9 ( 2 ) 2 2 7 6 8 9 8 6 0 0 . 4 2 5 . 2 0 . 1 82 -S C C -6 5 0 -V E A -O . 5 3 9 5 6 4 ( 2 ) 2 3 3 7 8 3 7 6 2 0 . 4 2 7 . 1 0 . 1 1

F 3 -S C C -6 0 0- VE A - O 0 5 4 2 ( 3 ) 1 9 4 7 5 5 8 9 3 0 . 3 9 2 5 . 1 0 . 3 13 - S C C - 6 5 0 - V E A - 0 .5 3 9 5 2 3 ( 3 ) 1 9 2 8 9 0 7 6 2 0 . 3 8 1 0 . 2 0 . 1 2

(1) Type 10 + 8% SF (2) Type 10 + 3% S F + 40% BF S (3) Type 10 + 8% SF + 20% BF S.

h i g h d e g r e e o f r e i n f o r c e m e n t . T h e f i b e r c o n t e n t ,l eng th , a spec t ra t io , and shape p lay an impor tan t ro l e inc o n t r o l l i n g w o r k a b i l i t y o f F R C [ 1 ] . S u c h c o n c r e t e p r e -s e n t s g r e a t e r d i f f i c u l t y i n h a n d l i n g a n d r e q u i r e s m o r ed e l ib e r a te p l a n n i n g a n d w o r k m a n s h i p t h a n e s ta b l is h e dc o n c r e t e c o n s t r u c t io n p r o c e d u r e s [ 2] . T h e a d d i t io n a lc o n s o l i d a t i o n e f f o r t r e q u i r e d f o r s u c h c o n c r e t e c o n -t r ibu te s to the inc rease in cons t ruc t ion cos t . In o rde r top r o v i d e su f f i c i e n t c o n so l i d a t i o n , i m p r o v e f i b e r d i sp e r -s i o n , a n d r e d u c e t h e r i sk o f e n t r a p p i n g v o i d s, t h e F R C i so f t e n p r o p o r t i o n e d t o b e f l u i d e n o u g h t o r e d u c e t h ene ed for v ibra t ion cons o l ida t ion and fac il it a te p l acem ent .A n e x t e n s i o n o f th i s a p p r o a c h c a n i n v o l v e th e u se o f se lf -c o n s o l i d a t i n g c o n c r e t e ( S C C ) t o e l i m i n a t e , o r g r e a t l yr e d u c e , t h e n e e d f o r v i b r a t i o n a n d f u r t h e r f a c i li t a tep l a c e m e n t . A tr u l y f i b e r- r e in f o r c e d S C C ( F R - S C C )s h o u l d s p r e a d i n t o p l a c e u n d e r i t s o w n w e i g h t a n da c h ie v e c o n so l i d a t io n w i t h o u t i n t e r n a l o r e x t e r n a l v i b ra -t i o n , e n s u r e p r o p e r d i s p e r s i o n o f fi b e rs , a n d u n d e r g om i n i m u m e n t r a p m e n t o f ai r v o id s a n d l os s o f h o m o -g e n e i t y u n t il h a r d e n i n g . L a c k o f p r o p e r s e l f- c o n so l id a -t i o n o r i n t e n t i o n a l v i b r a t i o n a n d c o m p a c t i o n c a n r e su l ti n m a c r o - a n d m i c r o - s t r u c t u r a l d e f e c t s t h a t c a n a f f e c tm e c h a n i c a l p e r f o r m a n c e a n d d u r a b il it y .T h e i n c o r p o r a t i o n o f f ib e r s c a n s i g n i f ic a n t ly m o d i f yrheological prop ert ies as f ibers, by their ge om etr ical forms,in t e rac t w i th the aggrega te , hence inc reas ing the in t e rna lre si s tance to flow . Such in t e r fe rence should be reduced ,and a proper suspension of sol ids part ic les is necessary toprevent segrega tion in the v i c in i ty o f re s t r ic t ed a reas tha tcan result in blockage o f the f low. Typical ly, the redu ct ionin f ibe r l eng th a nd dec rease in the n om ina ! s i ze o f aggre -gate and aggregate volume reduce such internal resistanceto f lo w an d increase workabi li ty.P ro vid ing prope r re s is t ance to b l eed ing and segrega -t ion i s e ssen t ia l fo r the successfu l p rod uc t io n a nd cas t ing

o f S C C , e sp e c ia l ly w h e n r e la t iv e l y h e a v y m e t a ll i c f ib e r sa r e i n c o r p o r a t e d . A l a c k o f st ab il it y c a n l e a d to n o n - u n i -f o r m f l o w o f th e F R - S C C a m o n g c l o se ly sp a c ed o b s ta -c le s , i n c r e a s i n g i n t e r p a r t ic l e c o l l i s i o n a m o n g a g g r e g a t epa r t i c le s and f ibe rs . En sur ing adequa te st abi li ty ca n bese c u r e d b y r e d u c i n g t h e f r ee w a t e r c o n t e n t a n d / o r i n c o r -p o r a t i n g a v i s c o s i t y - e n h a n c i n g a g e n t (V E A ) . T h e l a t t erchoice enables the inc rease in wa te r and pas t e conten t s ,p e r m i t ti n g t h e l o w e r i n g o f a g gr e g at e v o l u m e a n d f l o win te r fe ren ce th ro ug h c lose ly spaced obs tac le s .Th e in corp ora t ion o f f ibe rs in SC C i s feas ib le [3 , 4 ];however , l imi t ed da ta a re ava i l ab le conce rn ing the t e s t -i n g , p r o p o r t i o n i n g , a n d p e r f o r m a n c e o f s u ch c o n c r e t e .R e se a r c h i s r e q u i r e d t o d e t e r m i n e t h e a d e q u a c y o f u s i n gt e s t m e t h o d s e m p l o y e d f o r r e g u l a r S C C t o e v a l u a t e t h er e s t r ic t e d d e f o r m a b i l i t y o f F R - S C C . F u r t h e r m o r e , i t i si m p o r t a n t t o e v a l u a te t h e i n f l u e n c e o f d i f f e re n t a spe c tso f m i x t u r e p r o p o r t i o n o n f re sh a n d h a r d e n e d p r o p e r t i e so f su c h c o n c r e t e .T h e o b j e c ti v e s o f th e s t u d y r e p o r t e d i n t h is p a p e r a r eto fur th e r e s t ab l ish the feas ib i li ty o f p ro du c ing and t e s t -i n g F R - S C C a n d e v a l u a t e t h e su i t a b il i ty o f t e s t in g t h er e s t ri c t e d d e f o rm a b i l i t y o f F R - S C C u s i n g w o r k a b i l i tyt es t m e t h o d s p r o v e n fo r n o n - f i b r o u s S C C . T h e s t u d ye v al ua te s t h e e f f e c t o f f ib e r v o l u m e a n d m i x t u r e p r o p o r -t i o n i n g o n f l o w c h a r a c t e r is t i cs a n d p r o p e r t i e s o f t h eh a r d e n e d c o n c r e te .

2 . EX P E R IM E N T A L I N V E S T I G A T I O N2 . 1 M a t e r i a l s a n d m i x t u r e p r o p o r t i o n i n g

T h e p r o p o r t i o n i n g o f t h e 1 6 c o n c r e t e m i x t u r e s e v a l -u a t e d i n t h i s p r o j e c t a re g i v en i n T a b le 1 , T h e m i x t u r e sw e r e p r e p a r e d w i t h a w e l l - g r a d e d r i v e r - b e d s a n d w i t h a3 9 2


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Khayat,Rousselspecif ic gravity o f 2.69, an ab sorptio n value of 1.2%, anda f ineness mo dulu s of 2 .36 . A c rush ed l imestone aggre -ga te wi th a nom ina l s ize of 10 mm was used . I ts spec if icgravi ty measu red 2 .79 , and i t s absorpt ion ra te was 0 .77%.A cont inu ously defo rme d shape s ta in less stee l f ibe r wi th am in im um t e ns i le s tr e ng th o f 830 M P a w a s u se d . Th ef ibe r le ng th o f 38 m m w a s s e l e c te d to be o n th e s a m eorder as the na r rowest spacing be twee n the tubes of thef i l l i ng c a pa c i ty t e s t , de sc r ibe d be low , t o e va lua t e t hein t e r f e r e nc e o f suc h spac ing on f l ow p r ope r t i e s o f t heF R - S C C . F u r t h e r m o r e , s u ch l e n g t h w a s f a v o re d t oe n h a n c e a n c h o r a g e o f t h e c o v e r o v e r r e in f o r c e m e n t i nFR C sections wh ich is necessary to delay the spall ing o fthe cover and enhan ce s t ruc tura l pe r form ance .A n a p h t h a l e n e - b a s e d h i g h - r a n g e w a t e r r e d u c e r(H RW R) wi th a speci fic gravi ty of 1 .21 and a so lid con -t e n t o f 42% w a s u se d , a long w i th a s et r e t a rd ing w a te rr e duc ing a ge n t, t o e nha nc e f l u id i ty r e t e n t ion . K e lc o -C r e t e V EA w a s inc o r po r a t e d in som e m ix tu r e s t o p r o -vide be t te r s tab i li ty . Th ree types of b ind er sys tems wereused, as shown in Table 1 . A b len ded s i lica fum e cem en tconta in ing approxim ate ly 8% s i l ica fum e, by mass , andtw o c e m e n t s m a de w i th 3% s i l i c a f um e a nd 40% b la s tf u r na c e s l a g ( B F S ) a nd 8% s i l i c a f um e a nd 20% B F Sreplacements were used . Th e Bla ine f ineness va lues ofthe C a na d ia n C S A Typ e 10 c e m e n t a nd B F S a r e 375 a nd445 m2/kg, respectively. Th e Ty pe 10 ce m en t is similarto a n A S TM C 150 Typ e I c e m e n t , e xc e p t f o r t he u se o fa m a x im u m o f 5% l im e s tone fi ll er .A c onc r e t e d r um m ixe r w i th a c a pac i ty o f 45 L w a suse d . The ba t c h ing se que nc e c ons i s t ed in m ix ing thes a n d a n d b i n d e r f o r 30 s e c o n d s . H a l f o f t h e m i x i n gw a t e r w a s th e n a d d e d a lo n g w i t h 5 0 % o f t h e H R W R .A f te r 30 s e c onds o f m ix ing , t he c oa r se agg r e ga t e a ndr e m a i n i n g w a t e r w e r e in t r o d u c e d . T h e s e t - re t a r d in ga ge n t a nd le f tove r H 1K W R w e r e t he n inc o r po r a t e d . Thef ibe r s w e r e i n t r oduc e d g r a dua l ly t o t he f l u id c onc r e t ef o l low e d by the V EA tha t w as p r e m ixe d w i th 1% o f t hem i x i n g w a te r . T h e c o n c r e t e w a s th e n m i x e d f o r tw om inu te s . N o a dd i ti ona l m ix ing w a s ne e de d fo r t he F l%SCC to ensure f iber dispersion.For the 16 mixtures given in Table 1, the contents ofc o a rs e ag g r e g at e a n d s a n d , b i n d e r , a n d H R W R w e r eadjus ted to obta in s lum p-f low va lues of 530 m m + 15 mmo r 65 0 m m + 1 5 m m . T h e e v a l u a te d m i x t u r e s w e r ediv ided in to s ix ser ies (A throu gh F) wi th each conta in ingmixtures wi th va r ious fibe r volumes . Series A consists ofc onve n t iona l ( C O N V ) m ix tu r e s w i th a t a r get e d s lum p o f200 m m . Th i s w as no t t he c ase f o r t he C O N V c onc r e t ew i th 1% f ibe r t ha t ha d a s lum p o f 140 m m . Th e S C C -650 m ixtures in se ries B and C have s lump f low va lues of650 + 15 m m w i th t he B m ix tu r e s inc o r po r a t ing V EAa n d m o d e r a t e W / C M c o m p a r e d t o t h o se i n s er ie s Cm a d e w i t h lo w e r W / C M a n d n o V E A . T h e l o w e rW /C M was necessa ry to m ainta in a h igh s tabi li ty o f thef resh concre te w hich is necessary to prevent segrega t iona nd b loc kage o f t he S C C . S uc h S C C ha d h igh b inde rcon tent to l imi t aggregate volum e and in te r fe rence wi t hthe steel f ibers. Th e m ixture s in series D are similar tot h o s e o f s e ri e s C , e x c e p t f o r l o w e r H 1 K W R c o n t e n t .

. . ~ 5 0 0 m m

7 5 m mF i g . 1 - V - F u n n e l t e s t u s e d t o e v a l u a t e f l o w a b i f i t y t h r o u g hr e s t r i c t e d s e c t i o n .

S uc h c onc r e t e ha d a s lum p f low o f 530 + 15 m m ( S C C -5 3 0 ), r e s u l t i n g i n a h i g h l y f lo w a b l e m i x t u r e , y e t n o tSCC . Th e SC C m ixtures in ser ies E and F a re preparedw i t h V E A a n d v a ri ou s W / C M a n d b i n d e r co m b i n a ti o n sto s e c u r e a h igh s lum p f low c ons i s t enc y o f 650 m m . Thevar ious types of b inders indica ted in Table I w ere chosento secure mixtures o f h igh w orkabi l i ty and s tabil ity but ofd i f fe rent leve ls of compress ive s t rength (45 to 85 MPa) .The f resh a i r content va r ied be tween 0 .5 and 3 .5% withthe low er va lues associated w i th the m ore f lu id concre te .

2 . 2 T e st in g m e t h o d sT h e s l u m p - f l o w t e s t w a s c h o s e n t o s t u d y t h e f r e ede f o r m a b i li t y o f t he S C C , w h i l e t he V - f unne l f l ow a nd

fil l ing capacity tests were used to evaluate the restr ic teddeformability. Th e V-fu nne l test was emplo yed to assessthe facil ity of aggregate partic les an d m orta r to change th eirf low pa ths and spread through a res t r ic ted a rea wi thoutblockage ( Fig. 1). Th is test is similar to tha t suggested byOzaw a e t a l. [5] . T he f low o f concre te i s noted as the t imebe tw e e n the r e m ova l o f t he o u t l e t a nd se i z u re o f fl ow .Th e f i ll ing capacity test (Fig. 2) was used to d eterm ine thefac il i ty of the c oncre te to de f orm readi ly amon g c lose lys p a c e d o b s t a c l es [ 6] . T h e c e n t e r - t o - c e n t e r s p a c i n gbe tw een smo oth copper tubes i s 50 m m in tw o d i rec t ions ,result ing in a clear spacing o f 34 m m . Th e test involves thecast ing o f concre te in the non- re inforced sec tion a t a co n-s tant r ate up to a he ight o f 220 m m and observing the easewi th wh ich the concre te flows in the res t r ic ted region .T h e r h e o lo g i c al p a ra m e t e rs w e r e d e t e r m i n e d u s i n gt h e IB B c o n c r e t e r h e o m e t e r [ 7] . T h e t e s t i n v o l v e sr e c o r d i n g t h e t o r q u e r e q u i r e d t o m a i n t a i n a g i v e nimpel le r angula r ve loc i ty tha t was var ied be tw een 0 and1.2 rpm . A tw o- f in ger impe l le r sys tem shears the con -

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Ma terials and Structures/Ma tdriaux et Constructions, Vol. 33 , July 2000

F i g . 2 - S c h e m a t i c o f t h e f i l l i n g c a p a c i t y a p p a r a t u s .

crete as it moves in a planetary motion . Th e test para-meters involving the dura t ion of the tes t, ma xim umimposed veloci ty, and nu mbe r of measured data pointswere adjusted to avoid segregation dur ing the test. Th edescending curve was used for the l inear regress ionanalysis to derive the relative yield value (g) and torqueviscosity (h) parameters to fit the Bing ham flo w mo del.The compressive strength was determined in compli-ance with AS TM C 39 standard [8] on 100 m m x 200 mmcylinders. Similarly, 100 m m x 100 m m x 350 m m prismswere used to evaluate the flexural toughness indices I5through I30 for the FRC in compliance with ASTM C1018. Th e S CC specimens were cast in two lifts with eachlightly consolidated with five strokes using a standard steelrod. This was fou nd to reduce the variability o f strengthresults of the SCC [9]. The specimens were dem olded oneday after casting and stored in lime-saturated water untilthe age of testing. It is imp orta nt to note th at the estimatederrors, with 95% confid ence limit, for the slump flow, fill-ing capacity, V-funnel flo w time, g and h parameters, and28-day compressive strength of highly flowable SC C areon t he o rd & o f + 20 mm, 6%, 0 . 5 s e c , 0 . 24 N m,1.1 Nm.s , and 1.6 MP a, respectively [10].

3. TESTING RESTRICTED DE FORM ABIL ITYOF FR-SCC

In general, the F1K-SCC was easy to handle and fin-ish, and the fibers appeared to be unifo rmly dispersed inthe matrix following casting and testing. The restricteddeformability of the concrete evaluated using the fillingcapacity is comp ared with the slump, flow in Fig. 3, an dto the V-fun nel test in Fig. 4. Th e results clearly indi-cate that the FR-SCC fol lows the general t rend foundfor SCC, whereby the restricted workability is enhancedwith the increase in slump flow. However, the relation-ship between the restricted flow capacity and slump flo wis depe nde nt on the fiber volum e. Th e results in Fig. 4show that for mixtures that do not exhibit segregationand flow blockage, there is a relat ion between the V-funnel and filling capacity values where the r eductio n o f

65oq o /9 0~... . . - ~ %55

} 45 olume_~ o 9 9I P

25 0 I , , , , , , , , , , ,0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 8 0 9 0 10 0

Box f i l l ing capaci ty (% )Fig . 3 - Relat ion between s lump f low and f i l l i n g cap ac i t y .

3 0 -- 9 F i be r vo l ume

! 5 - - ~ 0 % 0 . 5% 1%- CONV [ x x 9

!0 - SCC Lx 9 xo s o 2 : P o . .

- X = out of range.0 -- S C C - 6 0 0 - V E A - 0- 9 95 - - a 9 '~0o0 I ' I ' I ' I ' I I ' I ' t I ' I

0 10 20 30 40 50 60 70 8 0 90 100Box filling c a p a c i t y ( % )

Fig . 4 - Comparison of restricted f low determined by V-funnelan d f i l l i n g cap ac i t y tests.

flow time due to the increase in slump flow correspondsto an increase in filling capacity. Aga in such a relation -ship is fiber dependen t. For example, SC C w ith a slumpflow of 650 + 15 mm and 0.5% fiber can exhibit a flowtime and filling capacity values of 6 sec and 57%, respec-t ively, compared to 7 sec and 34% when 1% fiber isincorporated.

The e ffec t of f ibers , measured by the s lump-f lowtest, is clearly shown to be dependent on the fluidity ofthe concrete. The degree of workabili ty reduct ion dueto fiber addit ion is lower in the case of the SCC-530concrete than the SC C- 650 mixtur e. In real ity, thisshows the limitation of the s lump -flow test to assess theworkabili ty of FR- SCC . On the other hand, for a givenslump flow, the increase in fiber volum e resulted in a netreduction in filling capacity and an increase in V-funnelflow time. This was especially significant for the highlyflowable SCC. Th e dispersion of the data shows that forthe same slump-flow of 650 + 15 mm, the filling capac-ity and flow time values can vary from ap proximately 30to 85% and 4 to 13 sec, respectively.The f i ll i ng c a pac i ty o f non- f i b rou s SCC wi t h aslump flow of 650 mm was approximately 85% versus5% for the conventional concrete that had a slump of200 ram. Wh en the fiber volume was increased to 1%,a significant drop in deformability was obtain ed for bothmixture types. This is because a high volum e of steel

3 9 4


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g ( N m ) h ( N m . s )F i g . 5 - C o m p a r i s o n o f f d l i n g c a p a c i t y V a l ue s t o t h e g a n d h r h e o l o g i c a l p a r a m e t e r s .

f i b e r s i n c r e a s e s i n t e r n a l r e s i s t a n c e t o f l o w a n d i n t r i n s i cv i s c o s it y a s w e l l a s t h e d e g r e e o f f i b e r i n t e r f e r e n c e w i t ht h e f l o w t h r o u g h t h e r e s t r ic t e d s p a c i n g o f t h e b o x t e s t.D e s p i t e t h i s ; t h e f i l li n g c a p a c i ty o f t h e S C C - 6 5 0 - 1 m i x -t u r e w a s s i g n if ic a n tl y g r e a te r t h a n t h a t o f t h e C O N V - 1c o n c re t e o f a li m i t e d sl u m p o f 14 0 m m . T h e S C C - 5 3 0m i x t u r e s w i t h 0 . 5 a n d 1 % f i b e rs h a d s l i g h t ly l o w e r fi l l -i n g c a p a c i t y v a l u e s t h a n t h e c o r r e s p o n d i n g S C C - 6 5 0m i x t u r e s .T h e f i l l i n g c a p a c i t y r e s u l t s o b t a i n e d f o r m i x t u r e s i ns e ri es A t h r o u g h D a re c o m p a r e d i n F i g . 5 t o t h e g a n d hr h e o l o g i c a I p a r a m e t e r s . A g a i n , t h e f i ll i n g c a p a c i t yi n c re a s e s w i t h t h e r e d u c t i o n i n g t h a t i s a s s o ci a t ed w i t ht h e i n c re a s e i n s l u m p f l o w c o n s i s t e n c y . H o w e v e r , f o r ag i v e n g v a l u e , t h e f i b e r c o n t e n t a ff ec ts t h e v a l u e o f t h ef i l l i n g c a p a c i t y . S u c h c a p a c i t y d e c r e a s e s w i t h t h ei n c r e a s e i n t o r q u e v i s c o s i ty (h ). T h e i n c r e a s e i n f i b e rv o l u m e r e s u l t s i n a s h a r p i n c r e a s e i n h w i t h o u t a n yc h a n g e i n s lu m p f l o w . T h e h p a r a m e t e r s e e m s to h a v e ab e t t e r c o r r e l a t io n w i t h t h e f i ll i n g c a p a c it y o f t h e S C Ca n d F R - S C C t h a n t h e g v a lu e .

4 . E FF EC T O F P R O P O R T I O N I N G A N D C O N -SIST ENCY O N F R-SCC PERF ORMA NCET h e e f fe c ts o f f i b e r v o l u m e , i n c o r p o r a t i o n o f V E A t o

s e c u r e p r o p e r s ta b i li t y v e r s u s l o w e r i n g t h e W / C M , a n d.s lu m p f l o w c o n s i s t e nc y o n t h e p e r f o r m a n c e o f S C C a red iscussed . S ta r p lo ts [ 1 1 ] i n F i g . 6 a re u s e d t o r e p r e s e n tt h e t e s t d a t a o f si x re s p o n s e t y p e s d e t e r m i n e d f o r t h e 1 2m i x t u r e s o f s e ri es A t h r o u g h D . E a c h b r a n c h ( o r r a d iu s )o f t h e s t a r p l o t r e p r e s e n t s a r e s p o n s e w i t h t h e t e s t v a l u ei n d i c a t e d a t t h e e x t r e m i t y . T h e s c a le o f e a c h b r a n c hv a ri es f r o m t h e m i n i m u m r e s ul t o b t a in e d f o r t h e s e t o f1 2 m i x t u r e s n o t e d a t t h e c e n t e r o f t h e s ta r, t o t h e m a x i -m u m v a l ue i n d ic a t e d a t th e e x t r e m i ty . F o r t h e V - f u n n e lt e s t , g a n d h r h e o l o g i c a l p a r a m e t e r s , t h e v a l u e s a r ee x p r e s s e d i n t h e o p p o s i t e d i r e c t i o n w h e r e a s m a l l a n dfavo rab le va lue i s sh ow n to have a la rge r ad iu s . Th is i sd o n e t o m a i n t a i n a r e p r e s e n t a ti o n w h e r e b y a b ro a d e r s ta rr e p r e s e n t a t i o n c o r r e s p o n d s t o m o r e f a v o r a b l e f l e s h a n dh a r d e n e d c o n c r e t e c h a r a ct e r is t ic s .

4.1 Effect of f iber volum eA s d i s c u s s e d e a r l i e r , t h e i n c r e a s e i nf i b e r v o l u m e h a d a s i g n i f i c a n t i m p a c t o nr e s t r i c t e d f l o w p r o p e r t i e s d e s p ? t e t h ee q u i v a l en t s l u m p ~ lo v~ c o n s i s t e n @ w i t h i ne a c h m i x s e ri e s . T h e f i b r o u s c o n c r e t ew i t h t h e l e a s t h i n d r a n c e t o f l o w w a s t h eS C C - 6 5 0 - V E A m i x t u r e w i t h 0 , 5 % f i b e r st h a t h a d a l m o s t i d e n t i c a l f i l l i n g c a p a c i t ya n d V - f u n n e l f l o w v a l u e s a s t h o s e d e t e r -m i n e d fo r t h e n o n - f i b r o u s S C C .H o w e v e r , a 1 % f i b e r a d d i t i o n r e s u l t e d i nc o n s i d e ra b l e l i m i t a t i o n o f th e r e s t ri c t e df l o w . A s e x p e c t e d , t h e r e l at i v e l y r i g i dS C C - 5 3 0 m i x t u r e h a d t h e l o w e s t r e si d u a ld e f o r m a b i l i t y a f t e r f i b e r a d d i t i o n w i t h t h eu s e o f f ib e r s r e s u l t i n g i n c o n s i d e r a b l ei n c r ea s e i n t h e g a n d h v a lu e s .W i t h t h e i n c re a s e in f i b e r v o l u m e f r o m0 t o 0 . 5% , t h e H R W R d e m a n d w a s sl ig h tl y i n c re a s e d t om a i n t a i n s l u m p o r s l u m p f l o w c o n s i s te n c y w i t h i n e a c h

series (Tab le 1 ). Fu r the r increase in f iber vo lum e to 1%r e su l te d i n c o n s i de r ab l y g r ea t er d e m a n d o f H R W R f o rt h e C O N V a n d S C C - 6 5 0 - V E A m i x tu r es . T h e s l u m p o ft h e C O N V - 1 m i x t u r e w a s l i m i te d to 1 4 0 m m t h a t w a so b t a i n e d e v e n a ft e r a p p r o x im a t e l y d o u b l i n g t h e H R W Rc o n t e n t c o m p a r e d t o t h a t o f t h e 0 . 5 % f i b ro u s m i x t u r e .F o r m i x t u r e s o f s i m i l a r c o n s i s t e n c y l e v e l s w i t h i n e a c hs er ie s, t h e i n c re a s e i n f i b e r v o l u m e h a d l i m i t e d e f f e c t o n gb u t r e s u l t e d i n c o n s i d e r a b l e i n cr e a s e i n h ( t o r q u e v i sc o s -i ty ) . Fo r exam ple , f o r m ix tu re s in ser ies C (S C C -650 ) ,t h e a d d i t i o n o f 0 . 5 a n d 1 % f i b e r v o l u m e s i n c re a s e d t h e hv a l u e s f r o m 8 . 5 t o 1 2 . 2 a n d 2 1 . 3 N m . s , r e s p e c t i v e l y ,w h e r e a s t h e g va l u e s r e m a i n e d l o w a t 0 . 4 t o 1 .4 N m .F r o m a m e c h a n i c a l p o i n t o f v i e w , t h e a d d i t i o n o ff ib e r s h a d m i x e d e f fe c t o n t h e 4 5 - d a y c o m p r e s s i v es t r e n g t h . W i t h t h e i n c o r p o r a t i o n o f 0 . 5 % f i b e r, a s i g n i f-i c a n t i n c r e a s e i n s t r e n g t h w a s o b t a i n e d i n m i x t u r e s w i t hW / C M o f 0 . 3 8 - 0 . 3 7 ( se ri es C a n d D ) r e s u l t i n g i n a 10 to1 4 M P a g a i n , o r 1 5 t o 2 0 % r e l a t i v e s t r e n g t h . O n t h eo t h e r h a n d , t h e s t r e n g t h g a i n o f m i x e s i n s e r ie s A a n d Bw i t h 0 . 4 2 W / C M h a d 0 to 3 M P a s t r e n g t h g a i n w i t h t h ea d d i t i o n o f 0 . 5 % f i b er s . T h e i n c r e a s e i n f i b e r c o n t e n t t o1 % r e s u l t e d i n l o w e r s t r e n g t h ( 1 to 1 4 % ) t h a n t h e 0 . 5 %f i b r o u s c o n c r e t e . I n th e c as e o f t h e S C C - 6 5 0 - V E A - 1m i x t u r e , t h e s t r e n g t h w a s l o w e r b e c a u se o f t h e h i g h e rW / C M ( 0. 45 c o m p a r e d to 0 .4 2 ). R e g a r d le s s o f t h e m i xt y p e , t h e i n c r e a s e i n f i b e r v o l u m e h a d a s i g n i f i c a n t i n f l u -e n c e o n t h e I 3 0 t o u g h n e s s i n d ex .

4.2 R educing W /C M vs. incorporating VEA toenhance stabi li ty of FR-SCCE n s u r i n g u n i f o r m f l o w o f t h e S C C t h r o u g h r e s t ri c te da re a s a n d u n i f o r m s u s p e n s i o n o f c o n s t i t u e n t s i s e s s e n ti a lt o p r o v i d e g o o d q u a li t y c o n s t r u c t i o n . T h e i n c r ea s e ins t a bi li t y c a n b e o b t a i n e d e i t h e r b y r e d u c i n g t h e f r e e w a t e r

c o n t e n t b y l o w e r i n g t h e W / C M , o r b y us i n g a V E A t oi n c re a s e v i sc o s it y o f t h e S C C . T h e S C C m i x t u r e s o fs e ri e s B i n T a b l e 1 a re p r o p o r t i o n e d w i t h a V E A a n dW / C M o f 0 . 4 2 t o 0 .4 5 , w h e r e a s t h o s e i n se ri es C a re p r e -3 9 5


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Mater ia ls and St ructures /Mat~r iaux e t Co nst ructions ,Vol. 33 , July2000

t~~5

S e r i e s A S e r i e s B S e r i e s C S e r i e s DCONV-O S C C - 6 5 0 - V E A SCC-650 SCC-5308 % S F 8 % S F + 4 0 % B F S 8 % S F 8 % S FW / C M = 0 .4 3 W / C M = 0.42 - 0.45 W/CM = 0.38 W/CM = 0.37

4.4 5 1.5 77 1.4 83 1.8 582 0 . 5 % B lk * 6 . ! ~ , 4 8 . 5 ~ , 4 8 . 1 ~ 4

70 53 72 704.9 0 0.8 77 0.4 57 1.5 38

4 6 . 9 - - ~ B lk * 9 . 8 ~ 5 1 2 . 2 ~ 6 1 8 . 0 - - - - ~ 2870 18 56 23 82 20 84 20

NA 0 1.5 28 1.0 34 1.6 19N A - ) ~ I ~ 17 1 8 , 2 - - - ~ 13 2 1 . 3 - - ~ 7 2 0 . 3 - ~ 46

65 22 46 29 81 29 73 21* Blockingof flow through V-funnel L e g e n d

g F i l l i ng capacityh ~ V- funne l

45-d f e I30

Fi g . 6 - S u m m a r y o f r e s u h s o f m i x t u r e s o f s e ri es A t h r o u g h D . H i g h e r open areaso f p o l y g o n s ind ica te genera l ly be tter per formance o f F R .- S C C . T h e g , h, V - f u n -n e l axes are reversed w ith m in im um va lue correspond ing to t ips o f the branch .

30 725 "12 0 "1 5 "1 0 "5 "0

V f - 0 5% ] SCC-650-VE A-0.51 Age= ' 4 5 d a y s / 3% S F + 40% slag CM =560 kg/m~, / f e=56 MPa WlCM=0.45

. . . . scc. o.o' / 8% SF CM= 530 kg/m

scc-~a0-0 .s "- - , ,__ - , , , ~ - _ ~fc = 70 MPa W /CM = 0.43

I l 1

com press ive s t r eng th va lues . Suc h s t r eng thw a s l o w e r fo r th e S C C - 6 5 0 - V E A m i x t u r eb e c a u s e o f t h e r e p l a c e m e n t o f 4 0 % o fc e m e n t m a s s b y B F S , l o w e r s i li ca fu m e c o n -t e n t, a n d h i g h e r W / C M . O t h e r w i s e , t h ep e r f o r m a n c e o f b o t h S C C t y p e s i s f ai rl y s i m -i l a r . T h e t o r q u e v is c o s it y o f t h e S C C - 6 5 0 -V E A c o n c re t e m a d e w i t h o u t a n y f ib e rs w a s6 .1 N m . s c o m p a r e d t o 8 . 2 N m . s f o r th eS C C - 6 5 0 m i x t u r e t h a t c o n t a i n e d a l o w e rv o l u m e o f p a s t e a n d g r e a t e r a g g r e g a te v o l -u m e . T h i s d i f fe r e n c e w a s m a i n t a i n e d f o r t h eF R - S C C m i x tu r es .

I n g e n e ra l , t h e S C C - 6 5 0 - V E A a n dS C C - 6 5 0 m i x t u re s m a d e w i t h 0 . 5 % f i b e re x h i b i t e d t h e b e s t o ve r al l p e r f o r m a n c ea m o n g t h e 1 2 m i x t u r e s p r e s e n t e d i n F i g . 6.T h i s i s r e f l e c t e d b y t h e s iz e o f t h e s t a rp l o ts . F o r m i x t u r e s m a d e w i t h 1 % f i b e r,t h e S C C - 6 5 0 c o n c r e t e h a d t h e b e s t o v e ra l lp e r f o r m a n c e . T h e f i l l in g c a p a c i ty o f t h isc o n c r e t e r e m a i n s h o w e v e r l o w b e c a u s e o ft h e h i g h v i s c o s i t y a n d f i b e r l e n g t h .T h e f l e x u r a l l o a d - d e f l e c t i o n c u r v e s o fS C C - 6 5 0 - V E A a n d S C C - 6 5 0 m i x t u r e sm a d e w i t h 0 . 5 % f i b e r v o l u m e a re p r e -s e n t e d i n F i g . 7 a l o n g w i t h t h e r e s u l t so b t a i n e d w i t h t h e c o n v e n t i o n a l c o n c r e te .T h e d a t a c o r r e s p o n d t o t h e r e s u l ts o f a s i n -g l e f le x u r a l b e a m f o r e a c h c o n c r e te ; h o w -e v e r , t h e t o u g h n e s s i n d i c e s a r e r e p o r t e d a st h e a v er ag e o f t w o t e s t s a m p l e s . T h e S C C -6 5 0 - V E A c o n c r e t e h a d a c o n s id e r a b l yl o w e r c o m p r e s s i v e s t r e n g t h t h a n t h eC O N V a n d S C C - 6 5 0 m i x t u re s (5 6 M P ac o m p a r e d t o 7 0 a n d 8 2 M P a ) , a n d h a d as i m i l a r f l e x u r a l s t r e n g t h a s t h e C O N Vm i x t u r e b u t a l o w e r s t r e n g t h t h a n t h eS C C - 6 5 0 m i x t u r e . I n g e n e r a l l t h e, C O N V - 0 . 5 a n d S C C m i x t u r e s d e v e l o p e d2 s i m il a r f l ex u r a l s t re n g t h s w i t h t h e C O N Vc o n c r e t e e x h i b i t i n g s l ig h t ly la r g e r m e a ns t re n g t h . B o t h S C C m i x t u r e s d e v e l o p e dg r e at e r t o u g h n e ss th a n t he C O N V c o n -c r e t e t h a t c a n b e d u e t o t h e l o w e r s ti ff ne s so f th e l o a d - d e f o r m a t i o n c u r v e o f t h e S C Cc o n c r e t e g i v e n i ts l o w e r c o a rs e a g g r e g a t e c o n t e n t . T h em e a n I 5 a n d I 30 t o u g h n e s s i n d ic e s o f t h e C O N V - 0 . 5

c o n c r e t e w e r e 4 . 7 a n d 2 2 . 2 , r e s p ec t i ve l y . T h e s e v a l u e sw e r e 4 . 8 a n d 29 .1 f o r t h e S C C - 6 5 0 - V E A - 0 . 5 m i x t u r ea n d 4 .9 a n d 2 9 .2 f o r t h e S C C - 6 5 0 - 1 m i x t u r e .

0.5 1 1.5Deformation ( m m )

F i g . 7 - F l e x u r a l load-def lec t ion curves o f m ix tures w i t h 0 . 5 % f ib e r .

p a re d w i t h o u t a n y V E A b u t w i t h a l o w e r W / C M o f 0.3 7.T h e f o r m e r m e t h o d e n a b l e s t h e r e d u c t i o n o f a g g re g a tev o l u m e t h a t c a n l i m i t in t e r fe r e n c e w i t h f i be r s. U n l i k et h e S C C - 6 5 0 - V E A , t h e S C C - 6 5 0 m i x t u r e s e x h i b i t e ds o m e s e p a r a t io n o f pa s t e a t t h e o u t e r e d g e s o f t h e s p r ea do u t c o n c r e t e d u r i n g t h e s l u m p f l o w t e st .H P , , W R d e m a n d i n th e S C C - 6 5 0 - V E A m i x t u re s w e r el o w e r th a n t h o s e fo r th e S C C - 6 5 0 c o n c re t e m a d e w i t h o u t

a n y V E A b e c a u s e o f t h e h i g h e r w a t e r c o n t e n t o f th e f o r -m e r m i x tu r es . T h e d e m a n d o f t h e H R W R w a s a p p ro x i-m a t e l y 5 0 % h i g h e r f o r t h e S C C - 6 5 0 m i x t u r e w i t h o u tf ib e r, b u t o n l y 1 0 % h i g h e r w h e n 1 % f i b e r w a s e m p l o y e d .Th e m ajo r d i f fe r ence be tw een the r esul ts sh ow n in F ig . 6f o r t h e S C C - 6 5 0 - V E A a n d S C C - 6 5 0 m i x t u r e s l i e s i n t h e

4 . 3 P e r f o rm a n c e o f S C C - 6 5 0 vs . S C C - 5 3 0T h e d a t a o f s e ri e s C a n d D o f F i g . 6 c o m p a r e t h e

c h a ra c t er is t ic s o f t h e S C C - 5 3 0 a n d S C C - 6 5 0 m i x t u r e sm a d e w i t h o u t a n y V E A w i t h t h e f o r m e r c o n c r e te b e i n gn o t t r u l y s e l f - c o n s o l id a t i n g b u t r a t h e r a h i g h l y f l o w a b l ec o n c r e t e r e q u i r in g m i n i m a l v i b r a t io n f o r p l a c e m e n t a n d3 9 6


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Khayat, Rousselconso l ida t ion . Thes e mix tu res d if fer on ly in the H R.W Rc o n c e n t r a t i o n r e q u i r e d t o e n s u r e t h e t a r g e t t e d s l u m pf low consi st ency . T he g va lues o f the SC C-5 30 mix tu resw e r e c o n s is t e n tl y h ig h e r t h a n t h o se o f t h e m o r e f l o w a b leS C C - 6 5 0 . H o w e v e r , b o t h s ets o f m i x t u r e s d e v el o p e ds imi la r to rque v i scos i ty va lues . In the case o f the n on -f i b ro u s S C C , b o t h m i x t u r e s h a d s i m i l ar V - f u n n e l f l o wt imes desp i t e the d i f fe rence in s lump-f low va lues , ind i -ca t ing d if fe ren t f il l ing capac i ty leve ls . W i th the inco r po -ra t ion o f f ibers , the S CC -530 m ix tu re exh ib i t ed a l im i tedf i l ling capac i ty comp ared to the SC C-6 50 m ix tu re . Th et o u g h n e s s i n d ic e s o f t h e S C C - 5 3 0 m i x t u r e s m a d e w i t h0 .5 and 1% f iber were s l igh t ly lower than the SCC-650mix tu res desp i t e the conso l ida t ion o f the spec im ens p re -p a r e d w i t h t h e S C C - 5 3 0 m i x t u r e s.

5 . C O N C L U S I O NBased on the resu l t s p resen ted above , the fo l lowingconc lus ions a re warran ted :1 . H i g h l y f l o w a b l e , y e t c o h e s iv e , F R - S C C c a p ab le o fspead ing in to p lace wi thou t b lockage can g rea t ly fac i l i -t a te c o n s t r u c ti b i li t y o f F R C . S u c h c o n c r e t e w i t h h i g hs lu m p f l o w o f 65 0 m m c a n d ev e l o p c o m p r e s s i v es t reng ths and f l exu ra l tough ness s imi la r to those o f con -ven t iona l FR.C tha t i s v ib ra ted in to p lace .2 . A s i n t h e c a se o f n o n - f i b r o u s S C C , t h e s l u m p f l o wtest and rheo log ica l parameters a re n o t su f f i c i en t to eva l -u a t e t h e r e s tr i c te d d e f o rm a b i l i ty o f F R - S C C . T h e f i ll -i n g c a p a c i t y o r V - f u n n e l t e s t s h o u l d b e u s e d t o a s s e s s

wo rkab i l i ty and b lockage res i s tance . Th i s i s espec ia l lyi m p o r t a n t w h e n t h e f i b e r v o l u m e i n c re a s es c a u s in gg rea te r h ind rance o f sp read ing . Fo r mix tu res w i th a f il l -ing capac i ty g rea te r than 30%, the f i l l ing capac i ty t es tbecom es m ore su i tab le to assess the res t r i c t ed defo rm a-b i l ity than the V-fu nne l t es t.3 . Fo r a g iven s lump f low and 2 va lue , the increase inf iber con ten t reduces the f i l ling capac i ty and increases h .T h e r e l a t i o n s h i p b e t w e e n f i l l i n g c a p a c i t y o n t h e o n eh a n d a n d g a n d s l u m p f l o w o n t h e o t h e r h a n d i s d e p e n -d a n t o n f i b e r v o l u m e .4 . Desp i t e the 3 8 -m m long f ibers wh ich a re s imi lar in s izeto the m in im um c lear spacing be tw een obs tac les o f the f i l l-ing capac i ty t es t , h igh defo rmab i l i ty was ob ta ined whenthe f iber vo lum e was l im i ted to 0 .5%. At 1% f iber , thefdl ing capaci ty was low bu t s t i l l considerably greater than

t h a t o f t h e C O N V m i x t u r e . W i t h t h e d ec re a se i n f i b e rl eng th to ensu re compat ib i l i ty wi th the nar rowes t d imen-s ion between the various obstacles , the f i l l ing capaci ty ofthe FP, .-SCC wi th 1% fibers should increase.5 . B o t h t h e S C C - 6 5 0 m i x t u r e s m a d e w i t h 0 .3 7 W / C Ma n d n o V E A , a n d 0. 4 2 W / C M a n d V E A d e v e l op e d s im i -l a r f resh p roper t i es and toughness ind ices tha t we re co n -s i d e r a b l y g r e a t e r t h a n c o n v e n t i o n a l c o n c r e t e t h a tr e c e i v ed i n t e rn a l v i b ra t io n . T h e f o r m e r m i x t u r e t y p ee x h i b i t e d h i g h e r s t r e n g t h b e c a u s e o f i ts l o w e r W / C Ma n d m o r e f a v o ra b l e b i n d e r t y p e .6 . A s in t h e c as e o f C O N V m i x t u r e w i t h 2 0 0 m m s lu m p ,the increase o f f iber vo lume o f the FP , .-SCC f rom 0 .5 tot % resu lted in a significant increase in ductility.7 . P r o p o r t i o n in g S C C w i t h l i m i t e d s l um p f l o w o f 5 3 0m m c a n n o t e n s u r e s e l f - c o n so l i d a ti o n b u t c a n b e u s e fu lfo r cas t ing p la in o r l igh t ly re in fo rce d sec tions w i th l im -i t ed nee d fo r conso l ida t ion .

R E F E R E N C E S[ 1] B a l a g u r u , P . a n d S h ah , S . , ' F i b e r - R e i n f o r c e d C e m e n tComposites' , (Mc-Graw-Hill, Inc., 1991).[2 ] 'AC I Manua l o f Con cre te P ra t i ce Pa r t 5 ' (Amer ican C oncre teInstitute, 1993).[3] Yang, C .-A., Ch ern, J .-C. and M iao, B., 'Effects of s teel f iberconten t on properties of high-performance concrete' ; in 'H igh-P e r f o r m a n c e C o n c r e t e ' , S u p p l e m e n t a r y P a p e r s o f A C IInternational Conference, Malaysia, (1997) 355-369.[4] Ro y, C., 'High-perform ance, fiber-reinforced self-consolidatingconcrete' , Technical Re port , U niversit4 de Sherbrooke (1996).[5] Ozawa, K., Sak ata, N. a nd Ok am ura, H ., 'Evaluat ion of self-

c o m p a c t i b i l i t y o f f r e s h c o n c r e t e u s i n g t h e f u n n e l t e s t ',Proceedings, Japan Society of Civil Engineering (1995) 59-75.[6] Yurugi , M ., Sakata, N., Iwai , M. and Sakai , G., 'M ix prop ort ionfor highly workable concrete ' , in 'C onc rete 2000' , Proceedings,Dundee (1993) 579-589.[7] Beaupr~ , D . , 'Rheo log y o f h igh pe r fo rmance concre te ' , Ph .D .Thesis , Universi ty o f Bri t ish Columbia, Canada (1994).[8] Annual Boo k of AS TM Standards ', volume 04.02 C oncrete andAggregates (American Society for testing and M aterials, 1996).[9] Takenaka, H., Kakizaki , M ., Abe, Y. and Okada, M ., 'Effects ofspecimen preparation on the pro pert ies of fresh and harde nedh i g h f lu i d i t y c o n c r e t e s ' , P r o c e e d i n g s , F o u r t hC A N M E T / A C I / J C I I n t e rn a t i o n a l S y m p o s i u m - A d va n ce s i nconcrete technology, Japan (1998) 605-616.[10] Khayat , K., Ghezal , A. and Hadriche, M., 'Factorial designmode ls fo r p ropor t ion ing se l f -conso l ida t ing concre te ' , Ma t e r .Struct. 32 (1999) 679-686.[11] Toit , S., Steyn, A. and Stunpf, R. 'Graphical Exploratory D ataAnalysis' , (Springer Te xts in Statistics, 1986).

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