租骨材の特性が超高強度コンクリートの力学的性質に及ぼす影響

(1)

Architectural Institute of Japan

NII-Electronic Library Service Arohiteotural エnstitute 　of 　Japan

【

論文

】

　　　日本建築学会構造系論文報告集第 451 号

・

1993 _年_{9 月}

Journal

　of　Struct

，

　Constr

．

　Engng

，

　A正

J

，

　No

．

45t

，

　Sep

．

，

1993

EFFECTS

OF

COARSE

AGGR

．

EGATE

CHARACTERISTICS

　　

．

ON

MECHANICAL

PROPERTIES

’

OF

ULTRA

HIGH

−

STRENGTH

CONCRETE

粗

骨材

の

特性

が

超高強度

コンク

リ

ー

ト

の

力学的性質

に

及

ぼ

す

影響

’

Masa

ツosノ匠」【ン

11

（

IZAKI

＊ and 　

Hidetoshi

EDAHfRO

＊＊

柿崎

正

義，枝広英俊

　 This

　report 　made 　a 　test　study 　abQut 　effects 　of　_quality　and 　

kinds

　of　coarse 　aggregate 　and 　

400 kN

crushing 　value 　and　maximum 　size　on 　compressive 　strength 　ahd 　crushing 　condition 　anCl　compress

．

ive

deformation

　of　ultra　

high・

strength 　concrete （about 　

90 −

130 MPa

）

．

The

　results 　are　shown 　as　

fol−

lows，

（

a

_）

，

When

400 kN

crushing 　value 　of　aggregate 　

is

11−

23

％ and 　water

−

to

−

cementitious 　ratio 　

is

less

　than　

O

，

25 ，

this

　strength　

is

　concluded 　

for

．

material 　and　mixing 　

proportions

…of　ultra 　

high・

strength 　concrete

．

_（

b

_）

．

Compressive

　strength 　of　concrete 　

increase

　with 　

decrease

in

　maximum 　size of　coarse　aggregate

，

Compressive

　strength 　of　concrete 　made 　with 　

limestone

　and　

hard

　sandstone

（

A

）

graded

　at　

10 −

5mm

is

　about 　

lO6

MPa

　and 　about 　

ll7MPa

，

　which 　

is

2 −

6

％

higher

　than　that　of concrete 　made 　with 　a　

grading

　of　

20−5

　mm

，

_（

c

_）

．

Co

皿

pressive

　strain 　

increase

　with 　

decrease

in

grading

　of　coarse 　aggregate

．

When

　compressive 　strength　of　rock 　reduces

_，

　we 　can

’

t　

find

　any 　

differ

・

ence 　

in

grading

，

_（

d

_）

．

In

　order 　

to

_get

　compressive 　strength 　of　ultra　

high−

sfrength 　concrete

_，

it

is

necessary 　to　raise　compressive

．

strength 　of　rock 　and 　crushing 　strength

．

　and 　

grading

_（maximum size

_）

of　coarse　aggregate 　and　

bonding

between

　coarse　aggregate 　and　mortar 　and 　at　

the

　same 　

time

しobring 　strength 　and 　

deformation

　of　aggregate 　close 　to　strength 　of　aggregate 　

tind

deformation

　of matriX 　mOrtar 　Or　

inCreaSe

it

．

　

Ke

∬roon ［

lk

：ultra

−high

strength

concrete

_，

₄₀₀

k

V

　

crushing

uatue

_，

kind

Of

aggregate

_，

water

−

　t7

　　　　　　　　　cententitious 厂atio

_，

　comPressive 　S’rain

　　　　　　　　　

超萵強度コンクリ

ー

ト

，

400kN

破砕率

，

粗

骨材の種類

，

水

結

合材比

，

圧縮ひずみ度

　　　　　　　

1

1 ．

lntroduction

　

Recent

progress

in

止e　

development

　of　

high

．

range 　water

−

reducing 　admixture 　

has

　made 　

it

　easy 　

to

ptoduce

high

　strength 　concrete

．

High

　strength 　cast

−in−place

　concrete 　of　

41 −

48 MPa

degree

　specified

design

　strength 　

is

　now 　commonly 　used 　

in

the

　construction 　of　

high

・

rise 　reinfQrced 　coIlcrete 　

buildingsi

）

’

3〕

_．

Furthermore

_，

the

　use　of　mixtures 　such 　as　silica　

fume

，

fly

　ash　and 　

ground

granulat

_俘

d

blast

−

furnace

　slag

makes 　

is

possible

to

produce

　ultra

−

high

　strength 　concrete 　of　over 　

100 MPa

degree

　strength

，

　and 　many

studies 　on 　

the

　use 　of　

these

　mixtures 　

have

been

　conducted 　

in

　the　

past

壬ew 　

Years4

）

−

6 〕

・

24 ］

・

32）

−

34｝

_，

　

Ahigh

　compressive 　strength 　

in

　concre

’

te

is

thought

to

depend

_primarily

　on　

the

　water

．

to

−

cdmentitious ratiq_，　

but

　compressive 　strength 　

ls

　also　

influenced

by

the

types

　of 　coarse 　aggregates 　used _，　

the

400 KN

crushing 　strength 　of　

the

　coarse 　aggregate

_，

　and　

the

　aggregate

_／

mortar 　

bbnd ．．

Detailed

　analysis 　of　

the

existing 　studies 　on 　

this

_、

．

subject 　revealed 　

the

following

：

・

　　

a

_）

The

　compressive

．

1strength

　of　concrete 　

is

greatly

influenced

by

the

　cornpres

_串

ive

　strength

properties

　of　

the

　rock 　used 　

in

the

　concrete _，　and 　may 　vary 　considerably 　

depending

　on　

the

brittleness

　of

the

　_rock7 ］

_．

』

　　

b

）

　The

　compressive

．

strength 　of　concrete

_，

　where 　the　water

−

to

−

cementitious 　ratio 　

is

　constant _，　

has

been

　reported 　as　

increasing

　with 　a　reduction 　

in

　the　maximum 　coarse 　

tiggregate

　size　

in

　the　compounds ｝

・

9 ｝

，

＊ Kajima

　Technical　

Research

Institute

，

Dr

．

Eng

．

＃

Shibaura

Institute

　of　Technology

，

鹿島　技術研究所　専門部長

・

工博芝浦工業大学建築学科　助教授

一

₁₉

一

(2)

whereas other studies report

the

opposite,

that

compressive strength

decreases

with smaller maximum coarse aggregate sizeiO].

c)

When

coarse aggregate

is

added

to

the

mortar,

the

compressive strength of concrete either

decreases

in

proportion

to

the

ratio of aggregate

to

mortar

by

volumeg', or shows no

_proportional

decrease9).

d)

The

influence

on

the

compressive strength of concrete resulting

fro'm

different

kinds

of aggregate

is

seen

to

be

small when concrete strength

is

Iow,

but

increase

as concrete strength

becomes

higheri2).

e)

The

larger

the

maximum size and unit volume of coarse aggregate,

the

less

the

strain

in

proportion

to

cornpressiye strength]Z),

As

we

have

_pointed

out,

the

kind

of coarse aggregate used,･ as well as

its

_quality,

crushing value, shape, maximum size and absolute volume can all

have

significant effects on the strength characteristics of

high-strength

concrete, which many

_previous

studies

have

demonstrated.

However,

in

the

90--13o

MPa

degree

range of ultra

high-strength

concrete, the specific effects

have

not

been

made adequately clear.

The

purpose

of

this

study was

to

gather

basic

data

on

the

selections of aggregate and concrete mixing

proportions

fer

ultra

high-strength

cencrete.

This

research

involvecl

consideration of the effects

that

such

_properties

of coarse aggregate

(including

kinds,

crushing vatue,

_grading)

would

have

on

the

compressive strength of concrete, and on

the

cornpressive

deformation

characteristics

in

90-l30

MPa

degree

strength concrete.

Table1

Factors

and

Levels

KindsofRock

Speeimen

ll'wattti",'l'..i.'i/i"','\tti.,.ttil'.i'iiS'i'''i...rm..'''i''i"''''''""'.',ss..'g'ltpa'

ttttttt/t

.trrc

±.I.'/･./.#'･./mm'.

IlardSandstoneAHardSandstoneBQuartzS ¢histLirnestonex.1..'1sc..･Andesite

Waoer-totCernetttitiousRatioe

O.2S

O.S5

m

-

-KindsofCoarse Aggregate HhrdSandstoneAHhrdSandstoneBQiartzSehistLimestoneAr:desite

CaerseAggregateGradingofCoarse

Aggregate(mm)

20--S

20-15ls--le10-55-2.5

kindsofFine Aggregate

HtSand

HhrdSandstoneAIinestone-

-FineAggregateGradingofFine Aggregate(mm)

2.5 -

-

-Note:

'

'Water-to-{ceiTient ₊

_Sraca

_Fume)_iatio

Tab[e2

Physical

Propeities

of Coarse Aggregates

HardSanttsrone(A>

l..g.i..,,,l.-ms-uai.,..

,X/.ii.I･i･.,,..., " 2.62O.671,56 ssg-'is'･ee'ie･as+,l,,.,ii..l/l ' .i...:･'}rr"

ts.rrIffi.maurer,II'ge:''/:

" S9,S 20.1 145

xs"ee'.fi.,"l'S'3,iSIg'･

lj

$･/S'･tlSXL"/inL/j'"･f'ew"'.tag'/Li'

IS-10mm14.6 e,6Si1ct 10 2,GlO,5S1.565S:S 17,2 Liptstore ee 2.69O.35;,6160.0 . 104 IS-10mm23.1 O.SSx1or 10 2.68e.3s1.6360.S 23.e

QuartzSahist10

2.S8O.9fi1,56S9.6 t4,2 tS3 IS-IOmmILa O.7tr1ct HatdSandstoneP}10 2.tiSo,ssIA3

54.2

21,2 133 IS-10mm20,7 O,67i1ct

Antesite 10 2,57o.as1," 55,S 192 104 IS-10mm11 O.4611cr

(3)

-20-Architectural Institute of Japan

NII-Electronic Library Service ArchitecturalInstitute of Japan

-Table3

Physical

Properties of Fine

AggTegates

Note: '

_Pit

_Sand

Table4

Mixing Propertions

l Sand. SSI

i,l

'iE.l,ttt'tt.,,i.t,o,ee,S/-,l.gets:･.I/tti,$//:,,me/.',$'

//ew,

er-" , en,･"o

i

'"t

.

'-//:'ssii3V'gtt'qx･l..eeX///,ee.as,tew,wwklkisc/;/\,.i{,,,,g,X,i, " E60610974 2HLrdS#ndttone(A)

o,oseruIhedtandM'1esstit7gGeo61g974 IS,S6 o.es

3 o.ssSendIS171313

'

Sl!eso9S6 O.7S

'

4 Sand SSI79 amSSI1026

sLimatone'o."Cruthedsand14lasSSI" amG031016 IS,Sfi

o,"

6 o.sfSend'IStn311

.

313S42.9S6- P.7S

7HtrdSrmdstonoCB) ,O.15SnndM16SSSIT9 amGsSm LS,es

･o."

eQuatuschli; e.2st/,Sand241essel" 660S97gse IS,as O.66

9Andeskoo.asSEndu16Ssgl7Pan664m IS.SG o."

(MaximumSiteofCos"cAggrcsetc: 10mm)

2. Experimental

Factors

and

Criteria

Using

the'experimental

factors

and criteria

described

in

Table

1.

3. Materials

,

In

the

･experiments,

ordinary

portland

cement and

five

kincls

of coarse aggregate were used.

Aggregates

¢onsisted of two

kinds

of

hard

sandstones,

limestone,

_quartz

schist, and andesite.

The

physical

properties

of

the

coarse

aggregates

are shown

in

Table

_2.

Regarding

the

maximum aggregate sizes

Iisited

in

Table

2 in

th.e

20 to

5

mm range,

the

aggregates were classified according

to

the

JASS

s,

and were

in

the

center of

the

standard

grading

ranges

for

･their

size

designations.

The

_physical

_preperties

of

the

fine

aggregate are shown

in

Table

3. The

_principal

ingredient

of

the

high-range

water-reducing admixture was

_{polycarbonate-ether,}

and an air-controlling agent was also used.

Granular

silica

fume

(specific

gravity

2. 23,

approximate specific surface are a

23.

2

m21g) was used as a mineral admixture, at an accretion rate of

12 %

of cement

･by

weight33',

The

clternical compQs-ition of

the

silica

fume

was

97 %

Si02,

O.

09 %

A1203,

O.

09 %

Fe20s

ancl

O,

11 %

CaO.

Potable

city water was used

for

all concrete

mixtures.

,.

'

,+/

4. Mixing

Proportions

Table

4

shows mixing

_propertions

for

various

'types

of concrete used

in

the

experiments,

The

mortar

sample used

for

the

concrete mixtures shown

in

Table4

was

first

_passed

through

a

5mm

sieve,

5. Preparation

of

Specimens

aDd

Test

Methods

5'.

1 Preparation

of

Specimens

Rock

specimens

for

the

tests

on various

kinds

of rock were cut out of

_quarries

in

(4)

-21-the

form

of

₄₀

cm3

blocks,

then

eore-bored

from

three

directions

(x,

_y

and z) with

due

regard

to

_joints,

and

finally

shaped

into

cylinders

5

cm

in

diameter

and

10cm

in

length.

Seven

to

nine such cylinders

were

_prepared

frorn

various

kind

of rock specimens.

The

concrete specimens were made

in

accordance with

the

JIS

A

1132

standards

for

_preparing

concrete

for

tests,

using

3

cylinder specirnens of each

type,

10

crn

in

diameter

and

20

cm

in

length,

and cured

in

standard water

7 days,

2s

days

and

91 days

respectively.

We

made cosideration

for

results of specimens

based

on standard water

curing.

The

surfaces of

the

specimens on which

loads

were

to

be

applied were machine

_polished.

For

the

tests

of mortar, concrete was used which

had

been

_passed

through

a

s

mm

standard sieve, according

to

the

JIS

A1132

standards.

The

5cm

diameterXIOcm

length

mortar cylinders were

_prepared

and cured

in

the

same way as

the

concrete

for

the

$ame

_peiiocls

oi

time

before

being

used

in

the

experiment.

5.2 Experimental

Methods

Comprehensive

strength

tests

of rock specimens were

_performed

in

accerdance with

JIS

A

11os,

JIS

B

7733,

and

JIS

M

0302,

and

then

tested

after

being

cut and cured

in

standard water

for

24 hours.

The

400 kN

crushing

tests

were

_performed

in

accordance with

BS

812 Standard'3',

using a standard aggregate

grading

ef

10-15

mm.

Abrasion

tests

were

_perferrned

in

accordance with

JIS

A

1121,

with an aggregate

grading

of

_IO-5mm

and

20-5

mm.

For

both

concrete and mortar, compressive strength

tests

were

conducted at

the

ages of

7 days,

28 clays

and

91 days,

in

accerdance with

JIS

A!108,

using a

high-rigidity

compression machine with a eapacity of

4,OOOkN.

Strain

was measured up

to

the

maximum stress of concrete using strain

_gauges

of

60

mm

length

(three

times

the

maximum size of

the

coarse aggregate).

Gauge

readings were recorded until

the

maximum stress was reached, after which

further

deformations

were measured

between

the

_pressure

_plate

and

the

specimen, using a strain

gauge-type

displacement

gauge.

Photograph

1

shows

the

results of

the

tests

and strain measurements.

The

static

modulus of elasticity of rock specimens was

determined

by

monitoring

two

strain

_gauges

of

30

mm

_gauge

length

sirnultaneously, while stressing

the

specimens

to

33 %

of

their

failure

stress along

the

stress-strain curve.

The

test

rnethod

for

mortar samples was as outlined above, and

the

test

method

for

concrete was similar, except

that

a

30

mm and a

60

mm

_gauge

length

were

both

used,

Specimens

of

mortar and concrete were

tested

at an age of

7

and

28 days

using

formula(1)

below.

Ev,=(S,-S,)!e,-50

×

10-fi)･･････---･--･--･･･--･---･-･･-･････････---････----････----･･･--･･･(1)

where

:

E=static

elastic modulus

(NlmmZ)

S,==stress

when strain=50 ×

10-E

S,=::stress

l!3

maximum

load

(Nlmm2)

E,==strain caused

by

stress

S,

6. Analysis

and

Discussion

of

Test

Results

6.1 Effect

of

Coarse

Aggregate

9uality

on

Compres$ive

Strength

of

Concrete

(1)

Quality

of eoarse aggregate

Evaluation

of

test

results obtained

from

tests

_performed

by

the

Cement

Associatien

of

Japan

on

the

correlations

between

various

_properties

of cearse aggregate

has

revealed

that

the

degree

of significance coarse aggregate

has

in

concrete

is

influenced

by

the

crushing

strength

and

abraded

quantity

and

the

percentage

of solid volume and specific

_physical

_properties

of

the

aggregateiS).

The

tests

determinecl

the

principal

physical

properties.

Table2,

Figure

1

shows

the

results

in

the

present

study

(grading

10-5mm,

with some

in

the

20-5mm

grading

range) and

in

_previous

studies

(grading

20-s

mm)s}･']･is)-ig]･Zi)

for

the

relationship

betwebn

the

400 kN

crushing values of coarse aggregate and

the

quantity

of aggregate abraded, and the

_percentage

of solid volome.

In

the

10-5mm

_gradine

range,

the

_quantity

of abraded aggregate, which showed a

tendency

to

increase

with an

increase

of

the

400 kN

crushing values, was about

14 %

for

_quartz

schist, about

17 %

for

hard

sandstone

(A),

about

19 %

for

andesite, about

21 %

for

hard

sandstone

(B),

and about

23 %

(5)

NII-Electronic Library Service ArchitecturalInstitute ofJapan

Photographl

Compfessive

Testing

O

AndesiteS}Disuii)-nno

-

Lime$toneS)is)iabn)m

e

Hard

sandstonefi)T]iSMoptvm},

a

River

_{gravelPiniOm)n)}

"Sand

stonenmTou>

a

Cobble

stonenrms)iom)

N

Cru$hed stoneinm

Y

Crystalline schisttS)

*

-'FFzq=qawoq=m<

292T25.2321191715131197

Figure

₁

//1111

AQuartz

schist

OBasaltTe)ie}

APit

gravelnn)

@

ChertiP

VSguare

stonelS

"Amphiboleistan]

±

Quart2item)u)

S+S :Herd sandstone{A)+Plt sand, S+K:Harq sandston?{A)+Crushed

sandstenesand

St+S:Hard sandstone(e)+Pit sand, Q+S:auerti schlst+Plt sand,

A+S:Andeslte+Pit sand

L+S:Limes ±one+Pltsand, L+K:Llmestone+Crushed 11mestonesand

ca160aE

.140I120og

loooL

80o;

60edi 40E 2o:oUl S+KS+SSI+SL+S S+k S+S

･Sl

-S

L.S S+K S.S SI

+S

L+S S+K$.SSI+$ L.s

"or1 _{L.+K atS A,S} _{L-K a+S}A+S _{L+K Q+s A+s} _{L+K a+s A.s} za

･

_KINDS _OF _COARSE AGGREGATE

5Figure

2 Relationship

betvveen

Kinds

of

Coarse

Aggregate

afid

Compressive

Strength

of

Concrete

2006f 180gEEii6ots

i'

!

g.:4o8::

M120kgooo=100 eo MaximumVtilue

_OMeanValue

･

Ee ENumber ot testspeclmens

'

E7

""ss

ii

---･-li

e

x.

,, Mtnimumvaiue

Xsli--.-ss 5

₁₀

15 20 25 30

AGGREGATE CRUSHtNG VALUE OF 4eekN ,%

Relatienship

between

AbrF,decl

_Qvantity

and

Aggre-gate

Crushing

Value

Figure

₃

QUAFrrZ HAHDSAND- HARO SAND.ANDESrrE LIMESTONE SCHIST'STONEfA} STeNE(B}

KINDs oF

'HOCK.

spEclMEk

Relationship

between

Kinds of Rock Specimen and

Compressive

Strength

of

Rock

Specimen

tt

for

limestone.

Ttie

abraded

_quantity

of

harcl

sandstone

(A)

of

_10-5

mm

_grading

decreased

-about

₁₄

_%

in

comparison with

those

of

20-5

mm

_giading.

As

reported

by

M. Hisaka

and

H,

Numazawa

(

7 ),

on

the

quantity

of abraded aggregate

forhard

sandstone,

the

abraded

_quantity

of

the

basalt

(grading

20--s

mm)

was

the

lowest

at

13 %,

while natural coarse aggregate and

_pit

coarse aggregate

(grading

25-5mm),

and

crushed stone were

16 %,

and sandstone and

limestone

were

20-22

%.

The

abraded

_quantity

in

the

present

experiment was a

larger

quantity

of abraded stone

than

found

in

_previous

studies,

however

it

was still smaller

than

the

regulation of within

25 _%

which

_qualified

as "high

_quality"

crushed stone22).

Furethermore,

comparing

the

percentage

of solid volume and

the

400 kN

crushing ratio _,

there

_,was

no

'

apparent correlation.

(2)

Kind

of

Coarse

Aggregate

･

''

Figure2

shows

the

relationship

between

kind

of coarse,aggregate

(grading

10-5mm)'and

compressive strength of concrete.

It

indicates

that

_the

compressive strength of concrete

for

a

_given

c6ncrete

type

at

the

age of

28 days

(standard

water curing),

in

decreasing

erder according

to

type

of

.

(6)

1408E:

1305gi2di

i611oiEm100!8E

gok8

80 eMean

Value Hard Sendstone(A) +Crushed Sandstone SandCA}

olCr"sedLimestene+Limestenei-VeaQuartz---"a----Schlst+PIt'g

Sand Snd e-ae-p-"O"-di

opoI:-eV("----e

::

ee

tL---e)-m-e"edii

o

HardSand$tene{ANPits

ee

Grading IO.v5mrn WIC+SF=O.25

e

Hard Sandstone(B) +Pit 5and Andesite+PitSand Llmestene+Pit Sand

80

100 I20

l4e

160

180

200

COMPRES$SVE STRENGTH OF ROCK SPECIMEN , MPa

Figure

4 Relationship

between

CempTessive

Strength

of

erete and

Compressive

Strength

of

Rock

Specimen

O.T5

'e.-o.7oLXpt:2 e.6sBio= -E

e･6o82

o.ssomrve

:

oseJOwc OA5 100 110 120 130 140 150 160

COwrPRESStVE STRENGTH OF ROCK SpECIMEN,MPa

Figure5

Relationship

between

Cempressive

Strength

ancl

Etastic

Modulus

of

Rock

Specimen

concrete are

:

from

the

highest,

_quartz

schist and

_pit

sand atabout

118 MPa,

hard

sandstone

(A)

and

_pit

sand at about

114 MPa,

andesite and

_pit

sand at about

104 MPa,

hard

sandstone

(B)

and

_pit

sand at about

₁₀₂

MPa,

and

limestone

and

_pit

sand at about

98 MPa.

The

order of

this

list

is

almost

identical

to

that

of

the

rock specirnents

of

Figure

3 (from

7 to

9

specimens) ranked

by

average compressive strength

in

decreasing

orcter.

The

discrepancy

observed

in

_part

ef

these

two

ranking orders seems

to

have

been

caused

by

differences

in

the

internal

structure or composition of

the

rock specimens.

This

suggests

that

the

average compressive strength of rock specimens may vary with

the

diTection

(x,

_y,

and

z)

and

joint

in

which

the

rock

is

cut, and

is

thought

to

occur

in

the

way expressed

in

Figure3.

Figure

4

shows

the

relationship

between

the

compressive strength of concrete ancl compressive

strength of rock specimens

for

various

kinds

of aggregate.

Compressive

strength of concrete

for

limestone

and

_pit

sand and andesite and

_pit

sand showed results nearing

the

average compressive

strength of Tock specimens.

On

comparison,

the

compressive strength of mortar

tuTned

out

to

be

either nearly

_the

same as

the

average cornpressive strength of rock specimens, or even slightly

_greater,

maintaining a

balance.

In

contrast,

the

compressive strength of concrete made with

_quartz

schist,

hard

sandstone

(A),

hlard

sandstone

(B)

and

_pit

sand was

less

than

that

of rock specimens.

From

this we can

infer

that

the

compressive strength of

the

coarse aggregate/mortar

bond

or mortar

itself

was srnall compared

to

the

average compressive stTength of

the

rock specimens,

When

varying

the

kinds

of aggregate used

in

agiven concrete

type

at

the

age of

28 days

(standard

water curing)

to

determine

its

compressive strength, concrete made with

quartz

schist and

_pit

sand

[hard

sandstone

(A)

and sandstone sand,

limestone

and

lime

sand]

clemonstrated

the

largest

compressive strength.

When

increasing

the

aging

from

₂₈

to

91 days

to

increase

the

compressive strength, concrete

made

from

_quartz

schist,

hard

sandstone

(A)

and

_pit

sand

[hard

sandstone

(A)

and sandstone sand]

had

the

Iargest

compressive strength, while concrete made with andesite,

limestone

and

_pit

sand

[linestone

and

lime

sand]

had

the

smallest.

This

shows

that

the

is

clearly affected

by

the

con}pressive strength of

its

composite rock specimens, as shown

in

Figure

5. Rock

specimens made with andesite and

limestone

demonstrated

and average compressive strength of only

_lo4

MPa,

while rock specimens made

frorn

_quartz

schist and sandstone

(A)

showed a compressive strength of

153 MPa

and

145 MPa

respectively.

However,

_the

compressive strength of concrete made with

limestone

and

lirne

sand not only

increases

with

the

static modulus of elasticity of

the

rock specimen,

but

is

also

thought

to

increase

with

the

chemical

bond

formed

between

the

limestene

and

the

cement

_paste.

(7)

s

15o:[ 130Ez 110ooLg go

!

70

e

,,dimW

30ie=' to

e20$S

Q22%",

o2sxS)ii)

v3o$E)

l31kiop

i4oxn]

Asoxts)an)a')icssxm

D60$IS)n}

ltr6stsIS)ll)

S 10 12 14 16 18 20 22 24 26 28

AGGREGATECRUSHtNGVALUEOF40ekN,%

Figure6

Relatibnship

be.tween

Compressive

Strength

and

Aggregate

Crushing

Value

(WateT-to-Cementltlous

Ratio)

O

AndesiteS}T):E}ts)-mto

-

LimestoneS}iilie)imi)

e

Hard sandstones)nis)ie)m)m･

O

River _{graveli):SM)nni)}

"Sand

stonenTs]Tsn"

al

Cobble

stenenivie]:sn"

ew

Cru.Shed stoneiS)dT)

E

YCrystalline

schlseg) E ₁₅₀

AQuartz

schist

OB'asalt:t)is]

APit

gravelnn)

@

Chertie)

VSquare

stene,S)

trllinpbiboleds)n]

)i(

_{QUartzitett)ii]}

ur-taggx2g:

g-:8

130ltO9070503010

Largemark :Resultsofthis study Age:28 days

.e.S.S'.q

ee:g

WtC+SF

gre.-:)r

ow.za ¢

e.es) 8

Figure7

10 t2 14 16 18

20

22

24 26 2S AGGREGATECRU$HINGVALUEOF400kN,%

Relationship

between

Cempresslve

Strength

and Aggregate Crushing

Yalue

(Kinds

of Aggregate>

(3)

400kN

crushing value

Figure

6

shows

the

relationships

between

the

cornpressive strength of concrete and

the

400 kN

crushing values of coarse aggregate

for

various water-to-cementitious ratios obtained

in

the

_present

study

(gTading

10-5

mm,

large

marks),

together

with

the

results of

_previous

studies

(grading

20-5

mm, with some

in

the

25-5

mm

_grading

range)S)･i5]･i6LiS)･20)･Ei)･i4}.

The

compressive strength of concrete with a

･water-to-cementitious

ratio of

O. 25,

when

the

400 kN

crushing value ranged

from

17 %-23

%,

was

less

than

90-110

MPa.

When

the

400 kN

crushing valve of coarse aggregate ranged

from

U--ls

%,

the

compressive strength of cbncrete was

110-130

MPa.

In

contrast, with a water-to-cementitious ratio of

O. 55,

when

the

4oo

kN

crushing valve of coarse aggregate ranged

from

14-23

%,

the

com'pressive strength of concrete was

less

than

35 MPa.

Among

the

results of,the

_previous

studies, a compressive strength of

less

than

50 MPa

degrees

was observed

in

concrete with a water-to-cementitious ratio of

O. 40-O.

65

and a

₄₀₀

kN

crushifig value ranging

from

₁₀

%

to

27 %.

This

is

because

the

compressive

strength of mortar

is

tess

than

the

crushing strength of aggiegate,

Th.at

is,

.as

in

llltra

high-strength

concrete,

it

is

not

influenced

by

the

crushing strength of

the

coarse aggregate,

Figure

7

shows

･the

relationship

between

the

compressive strength of concrete and

the

400 kN

aggregate crushing value of coase, and

presents

the

results of

Figure

6 by

kind

of aggregate.

The

compressive strength of concrete with a water-to-cementitious ratio of

O,

25

ranged

from

90-130

MPa

degr'ee,

and

the

400 kN

crushing value of

the

aggregate ranged

from

_11-23

%

for

_quartz

schist,

hard

sandstone, andesite, and

limestone

coase aggregate materials.

With

a compressive strength of only

3s

'abie5

ll

,Lat8".lh,;p.,be.t::f,:e.",ligm,?Le,ss:,e.S.t:?;.gtllk,f)g,gg:,

llli.l:,S.e,gge,e,,f."cl.fa,

W,a,lel'"2

,C,e6

･

kN

brushing

value was

in

_the

14'23

%

range

foe

hard

sandstone

(A)

and

1imestone

coarse

gate.

From

the

test

results of

Figlires

6

and

7,

the

relationships

between

the

compressive strength of cen

crete, water-to-cementlotlous ratlo,

-25-'

ll･l.i'･k-eeff"･S･"Ftetag.eE.kff･aFee",

'g.e.rn.e[itrbovst.Rlltrew..kI･--.galEst,geEl.,

eewleeveM...,..X..-,.,gge.;vai

ge..ee"g'sEi""i"'tewaliew..ps,ta'ii

lee1ww.iilzaii.,les.,.,/iwa.lgfftwy"tk'a'X'me.ee

s35 s5S 14SA.S,23Limestone,

Ha:dsandstone(A) 90Sac<110 sas usA.s23Hardsandstone(Axu),iindesite,

Quarzschist,Limestone･

11osacs13o ses 11SA.S15Hardsandstene{N,

(8)

and

400 kN

crushing value

together

are shown

in

Table

5,

Therefore,

the

compressive strength of ultra

high-strength

concrete

is

_greatly

influenced

by

the

rock specimen, as well as

by

the

crushing strength and

kinds

of coarse aggregate used

in

the

mixture.

(

4 )

Grading

of

Coarse

Aggregate

Figure

8

shows

the

relationship

between

one-$ized coarse aggregate and

the

concrete

with a water-to-cementitious ratio of

O.25.

Here,

the

concrete shows a

tendency

to

increase

with a

decrease

in

the

maximum size of

the

coarse aggregate, as well as

in

the

case of one-sized coarse aggregate.

This

tendency was

the

same

fer

each

kind

of coarse aggregate, and also

held

true

for

concrete

in

the

present

study, as well as

in

_previous

studiesS)'g"2S"2`' with a

water-to-cementitious ratio of

O.55,

as shown

in

Figure9.

The

compressive strength of concrete rnade with

hard

sandstone

(A)

_graded

at

10-5

mm

is

about

117 MPa,

which

is

2-6

%

higher

than

that

of concrete made with a

_grading

of

20-5

mm.

On

the

other

hand,

the

compressive strength of concrete made

frorn

limestone

made with a

_grading

of

10'5

mm

is

only about

106 MPa,

which

is

1'2

%

higher

than

that

of concrete made with

grading

of

20J5

mm.

Concrete

made with

limestone

_graded

at

10'5

mm

has

a compressive strength about

4 %

Iess

than

that

grade

at

5'2.5mm.

8 13oEti5

12oz85r 1108imts 100!zaE goE

MOR-

5-2.5 10-5 15-10 20-15 20-5 e

TAR

e

_COARSE

_AGGREGATE

_OF

_ONE-SIZED,

mm

Figure8

ReLationship

between

Coarse

Aggregate ef

Sized

and

Compressive

Strength

of

Concrete

QHardsandstoneCA)

aLlmestone

Mxe;-'

s

e

/1::.s!

WIC+SF:O.25

_a

Age:2Bdeys

OHard

sandstene{A),

_nLTmestone,

-Tutt'T)

OCrushed

stenesu,

eHard

sandstoneN)

eQuartz schlst') , ARiver gravela)

iLRIvergravetiD 1.22Elg1.ozatsyS

O･8

g

E･,.,

MORTAR5

₁₀

₁₅

₂₀

25

30

35

40

(5-2.5)(10-5N15-10X20-15)

MAXIMUM SIZE OF COAnSE AGGREGATE _,mm

(ONE-SIZED

COARSE AGGREGATE}

Flgure9

Relationship

between

Maximum

Size

ef

Coarse

Aggregate and

Compressive

Strength

of

Concrete

Strength

Ratio

In

this

way, when a smaller

grading

of one-sized coarse aggregate

increases

the

concrete,

This

is

thought

to

be

because

the

boundary

surface of cement

_paste

(mortar)

and coarse aggregate

becomes

$maller, making

it

difficult

for

defects

to

forrn,

and

leaving

fewer

_gaps

between

the

coarse aggregates.

The

size of one-sized coarse aggregate at

the

maximum

hard

standstone

(A)

-aggregate

_(pit

_sand) _concrete

_is

_larger

_than

_that

for

limestone-aggregate

(pit

sand) concrete,

This

is

thought

to

be

due

to

the

incfeased

bond

strength

between

the

boundary

surfaces of

the

coarse

aggregate and mortor, which arises

from

differ-ences

between

the

surface structure and

the

percentage

of solid volume ef coarse aggregate,

There

was considerably more

fracturing

of coarse aggregate noticeable

in

broken

specirnens o{

Gra

'2'o-smm

le--5

_2o-s.m

10-5

Mtx.W/C+SF

O.2S,.Age:2S

days

(9)

Architectural Institute of Japan

,

limest6ne-aggregate

(pit

sand) concrete

because

the

400 kN

crushing value of

limestone

is

larger

than

that

of

hard

sandstone

(A)

(see

Photograph

2).

Here,

under stress, cracks

inside

the

'

,

aggregate concrete

_grew

with

increased

load

on

'tbe

specimen.'

It

was

thought

that

the

cracking speed

was

higher

after reaching

the

aggregate surface,

than

in

the

matrix mortar.

Further,

Johnston's2"'

experiments on

the

relation of net

tensile

strength and aggregate

_grading

have

shown

that

the

bond

strength

.be,tween

coarse aggregate and mortar.decreases with an

ingrease

in

the

maximum size and

grading/.of

the

coarse aggregate.

･

'

,

Frorn

the

results shown

in

Figure

8,

to

increase

the

compressive strength of concrete made

from

hard

.sandstone

(A)

and

limestone,

it

is

adviaable

to

increase

the

cementitious-to-water ratio so

that

the

concrete compressive,stre.ngth

does

not

fall

below

that

of

the

mortar

itself

by

using one-slzed coarse

aggregate, or

by

using a-one-sized coarse aggregate within

the

range that

has

a smaller strength

reduction

than

the,compressive

strength of

the'mortar,

Therefore,

in

order

to

_produce

concrete with a' compressive strength of

110-120

MPa

and a

water-to-c'ementitious ratio of

O. 2s,

it

is

recommended

to

us'e･hard sandstone

(･A)

with a

_grading

of

10-5

mm, or

limestone

ulith

a

_grading

of

'5-2.5mm.

_.

6.2 ･

Effect

of

Aggregate

Quahtity

on

Compressive

Deformation

of

Concrete

(

1 )

,Relation'ship

Between

Stress

'and

Strain

1)

Kind

of rbck s'pecimens

,

･

Figure

10

shows'the stress-strain curves

for

the

compressive

tests

and

tensite

tests

of rock specimens.

,'The

stress-strain.curves

for

rock specimens are approximately

linear,

up to

the

p6int

where stress

is

the

highe$t.

This

different

from

the

tendency

of such curves

for

concrete.

When

the

compressive stress of

rock specimens

is

100 MPa,

the

conipressive strain

is

about

27

×

10"`

for

andesite,

the

largest,

followed

by

about

20

×

10-`

for

limestone

and about

14

×

1.0-`

for

quartz

schist and

hard

sandstone

(A

or

B>,

showing variety among

the

kinds

of rock specilnens.

However,

the

compressive strain of

the

rock

specimen

_generally

decreases

with an

increase

in

the

compressives stress of

the

rock specimen.

The

same

tepdency

is

seen

for

the

tensile

strain of

the

rock specimen, which

is

about

O.

5

of

the

compressive

strqin

for

each of

the

rock specimens, except

for

andesite.

.

,

'

t

'

2)

Kind

of

Coarse

Aggregate

'

Figure

11

shows

the

stress-strain curves

in

the

high-stress

range,

including

the

region

frQm

maximum

r

'

t

_:

'160a'

t

E.

zy8i2o.thg2.6

so8zatsy

dem:E.

o.20

Figure

lO

10

O 10

STRAIN,xte-`

SLress-Stfain

Curyes

fgr

Rock

20

30

Specimen

t50a"･E.:::8

ioots$:zaw)

508:l8oo

10 Figurell

Stress-Strain

Concrete)

20

30

40 STRAtN,xlo-4

CuTves･

for

ConcTete

50

(Types

of

(10)

-27-stress

to

declining

stress,

forvarious

concretes

that

contain

different

coarse aggregates.

As

seen

in

the

figure,

while

the

stress-strain curves of concrete containing

limestone

and

_pit

sand, andesite and

_pit

sand

inereases

en a curve

in

the

increasing

stress region.

In

centrast,

that

for

concrete which cQntains

hard

sandstone

(A

or

B)

and

_pit

sand

does

so

linearly

in

the

increasing

stress Tegion.

However,

both

concretes show non-linear

deformation

characteristics.

Also,

the

stre$s strain curves show

irregularity

in

the

declining

region after maximum stress.

This

is

due

te

the

repeated re-distribution of stress.

On

the

other

hand,

the

curve

for

concrete containing

lirnestone,

andesite and

_pit

sand

falls

sharply

in

_the

declining

region after maximum stress,

indicating

ductile

_properties.

This

behavior

occurs

because

of

the

low

level

of compressive strength of

the

rock specimen.

Therefore

the

coarse aggregate

becomes-unable

to

withstand

the

cTushing energy of

the

concrete

immediately

after maximum stress, and suddenly

fractures,

resulting

in

weakness of

the

bond

strength

between

the

mortar and

the

coarse aggregate.

The

slopes of

the

curves

in

the

region subsequent

to

maximum stress

tend

to

differ

_greatly,

depending

on the

kind

of coarse aggregate, and

_particularly

on

its

crushing strength.

Photograph

₃

shows examples of

the

compressive

fracture

of

limestone-aggregate

concrete.

This

seems

to

indicate

that

the

nature of

the

breakage

was very similar

to

brittle

stress

fracture,

due

to

the

influence

of

the

small

difference

between

the

elastic modulus of

the

rock specimens and

that

of

the

mortar,

the

lesser

mechanical non-uniformity within

the

specimens, and

differences

in

bond

strengths3]).

At

a stress of

O.9a,

and above, surface

delaminatidn

_phenomena

started,

followed

by

mortar cracking,

in

every

type

of concrete.

3)

Grading

of

Coarse

Aggregate

Figure

12

shows

the

stress-strain curves

for

concretes with various of one-sized coaTse aggregates.

The

slope

falls

more sharply

for

ultra

high-strength

concrete containing

hard

sandstone

(A),

limestone

and

_pit

sand with

_grading

of

20-15

mm, subsequent

to'

maximum stress, compared

to

the

same concrete with

_grading

of

_10-5

mm.

This

indicates

that

coarse aggregate

becomes

unable

to

withstand

the

crushing

energy of

the

concrete

immediately

after

rnax-S80

150ca"swFwmozoe･L

100ococataorHquilmgeE

sogo

oo

Figure

₁₂

10 Stress-Strain

Aggregate)

20STRASNCurves

30

40

,X10-4for

Conerete

50

{One-Sized

imum

stress, and suddenly

fractures,

resulting

in

weakness of

the

bond

strength

between

_the

mortar and

the

coarse aggregate.

The

maximurn strains of concretes

that

con-tained

hard

sandstone

(A)

of

10-5rnm

and

20-15

mm

_grading

when

the

water-to-cementitious ratio was

O.25,

were

33

×

10+`

and

29

×

10-`

re-spectively.

The

maximum strain was

12 %

higher

for

the

10-smm

grading

than

for

the

20-15

mm

grading.

In

contrast,

the

maximum strain of

Gra

Photograph3

Limestone-Aggregate

Specirnens

Fractured

by

Compression

(11)

'

concrete

that

contains

limestone

in

_grading

of

10-5

mm as well

_as

in

_gracling

of

_20-15

mm were

both

about

the

same, at

25

×

10-4.

It

also appears

that

there

were no･differences

in

maximum strain

for

concrete made with

hard

sandstone.

On

the

other

hand,

when

the

water-to-cementitious ratio was

O. 55,

the

maximum stiain of

the

concretes containing'hard sandstone'in

grading

of

10-5

mm･was about

17 %

_gTeateT

than

that

with

_grading

of

20-15mm.

Futhermore,

limestone

with

_grading

10-5mm

showed about

28･%

_greater

strain at maximum compressive stress

than

concrete with a

grading

of

20-'5

mm of

the

same

coarse

aggregate.

cbarse aggregate and

the

rnortar,

Qr

the

greater

influence

than

the

fracturing

of

the

concrete

'

-(

2 ₁

Strain

'for

maximum c6mpressive stress

'

These

10-'

for

andesite and

_pit

sand,

₂₉

×

･10-4

for

sand, and

26

×

10+-

for･hard

'sandStone

CB)

and

'

This

tendency

agrees with

the-results

of

the

compressive strain of concrete

is

influenced

to

a

'speclmen.

_'

_･

pit

sand

fine

aggregate

_produced

higher

values when stress was

the

same,

bond

strengths of coarse aggregate and mortar

speclmens.

･

,

'

,7.

conchusioh

A

summary of

the

results

is

listed

below,

I. On

Compressive

Strength

1)effect

on

the

compr,essive strength of

the

2)

With

a water-to-cementitious ratio of

O. 25,

sand,

the

compTe$sive'strength

is

on

the

average strength of rock specimens.

In

contrast,

sand,

the

is

lewer

than

specimens.

The

compress･ive strength of u corppressive' strength of

the

eriginal rock used

3)

The

range of our research covered coarse

high-strength

concretes centaining

ll-23

%

'

limestone

with a water-to-cementitious ratio

increases

with a

decrease

'in'the

maximum size observed equally

in

each

kin

/

/t

wtmcowmi:ootq!(crFm

40

30TpXrco-208Em

10

When

the

water-to-cementitious ratio

is'large

compresslve

coarse

Figure

13

shows the compressive strains of concretes

for

compressive stress of

100 .curves

show

that

the

strain of concrete.increases

linearly

with an

increase

in

compressive stress

The

stTains of concretes at compressive stress of

110 MPa

degrees

were

limestonei

quartz

schist

pit

test

on

great

As

for

the

compressive strain ofconcretes according

to

the

kincls

of

fine

aggregate used

than

This

difference

is

thought

to

have

been

an

'effect

of

the

differences

between

r

90

tOO

110

120 130 140

COMPRESS:VE STRESS

OF

CONCRETE,MPa

Figure13

Relationship

6etween

Compressive

Stress

and

Strain

of

Concrete

,

the

bond

strength

between

the

strength of

the

mortar

itself,

seems

to

have

a aggregate on

the

maxjmum compressive strain of

-13o

MPa

degree.

,

in

declining

orther, about33 ×

,･ ancl

hard

sandstone

(A)

and

pit

sand, which was

_the

lowest

value.

the

compressive strain of rock specimens.

The

extent

by

the

compressive strain of

the

reck

concrete with

'

concretes with crushed sand,

by

about

6

×

10-`,

ancl

differences'

in,

the

eiastic moclulus of ToCk

'

A

reduption of

the

abraded

_quantity

and

400 kN

crushing value of coarse aggregate

h.as

a ¢ontrolling

concrete.

･

for

concrete containing

limestone,

andesite- and

_pit

about

the

same as

that

of

the

average copapressive

for

concrete containing

quartz

schist,

hard

sandstone and

pit

that

of

the

average compressive strength of rock

Itra

high-strength

concrete

is

strongly affected

by

the

kind

and

for

coarse aggregate.

,

'

aggregates with a crushing value of

400 kN,

with ultra

mixtures

_quartz

schist,

hard

sandstone, andesite and

of

less

than

O.

25. The

of

the

coarse aggregate used.

This.tendency,

wqs

ds

of coarse aggregate we examined,

The

'

(12)

r29-containing aggregate

_graded

at

10-5

mm was

frem

2-6

%

higher

than

that

of concrete with

20-5

mm

graded

aggregate.

The

mest effective

_grading

size varied acoording

to

the

kind

of aggregate used, with

10-5

mrn

grading

being

the

best

for

hard

sandstone, and

_5-2.5mm

being

the

best

for

limestone.

ll.

On

Compressive

Deformation

1)

The

stress-strain curve of

the

rock specimens was almost

linear,

with

the

degree

of strain

dropping

with an

increase

in

the

cornpressive strength of

the

rock specimens.

The

tensile

strain was

approximately

1!2

of

the

compressive strain.

2)

Depending

on

the

kinds

of coarse aggregate used,

the

stress-strain curve of

the

concrete,

including

the

region of maximum stress,

in

some cases showed a curved

increase

with

_greater

compressive strength of ro.ck specimens, and

in

other cases a

linear

increase.

When

the

degree

ofcompressive stress of

the

concrete was

high,

the

hysterisis

curve also showed a

large

increase.

The

slopes of

the

curves

in

the

declining

region subsequent

to

maximum stress

dropped,

_particularly

sharply when

the

cempressive

strength of

the

rock was small, when

the

maximum size of

the

coarse aggregate was

large,

and when

the,

compTessive strength of

the

concrete

increased,

leading

to

sudden

fracture

of

the

concrete.

The

the

reck specimens and

the

maximum size of

the

coarse aggregate, and

of

the

bond

strength

between

the

aggregate and

the

mortar

had

a

determining

influence

on whenther

the

concrete was subject

to

sudden

fracture

failure.

After

the

_point

of maxirnum'stress,

the

characteTistics of

the

curve

in

decline

differed

with the

types

of concrete,

in

some cases showing a redistribution of stress, and

in

other cases exhibiting

ductile

_properties.

The

pToportional

limit

stress, with

the

kinds

and

_grading

of coars'e aggregate, and compressive

strength set at a

degree

of

_90-130

MPa,

changed

from

O. 7-O.

8

ab,

3)

Compressive

strain

increased

with

decreases

in

the

maximum size of

the

coarse aggregate.

No

differences

were observed

through

changes

in

the

maximum size when

the

rock specimens was small.

Compressive

strain of concrete

incTeased

with

increases

in

the

absolute volume of coarse aggregate, with

increase$

uniformly occurring on a curve.

4)

The

maximum compressive strain

increases

linearly

with

increases

in

compressive stress

in･the

concrete.

The

compressive strain of concrete according

to

kinds

of coarse aggregate

increased

with

decrea$es

in

the

rock specimens.

The

maximum compressiye

strain

of

concrete, with

the

kinds

and

_grading

of coarse aggregate, and at a

degree

of

90-130

MPa,

changecl

from

O.23-O.33

%

in

compressive strength,

In

order

te

increase

the

compressive strength of ultra

high-strength

concrete,

it

is

advisable

_to

strengthen

the

rock specimens,

the

crushing strength of

the

coarse

aggregate, and reduce the maximum size of

the

_grading,

afid strengthen

the

bond

strength

between

coarse aggregate and mortar.

At

the

same

time

it

is

necessary

to

bring

the

value of

the

strength or

the

deformation

of

the

rnatrix mortar close

to

that

of

the

coarse aggregate, or

to

ensure

that

the

value of

the

matrix rnortar

is

somewhat stronger

than

that

of

the

coarse aggregate.

Acknowledgements

The

author

_gratefully

acknowledges

the

advice and suggestions

_provided

by

Masami

Murata,

Shibaura

FactoTy

chief,

Hiroyuki

Kataoka,

section chief of

Keihin

Ryoko

Concrete

Company,

Ltd.

_,

and

Kazuomi

Okamura,

_group

leader,

and

Toru

Kanda,

researcher, of

Fujita

Gijutsu

Kenkyusho.

We

also extend our

thanks

to

Yasuhara

Matsuura

and

Takushi

Kamiya,

both

of whom are construction

g[aduates

in

the

class of

1990

of

the

shibaura

Institute

of

Technology,

for

their

assistance

in

_preparing

this

_paper.

References

1)

Kaneko,

H,

and

Okamoto,

K.,

et al. :

High-Rise

RC

Buildings

Constructed

with

High-Strength

(Fc420

kgVcmZ}

Cencrete,

for

Community

Dwelling

in

Park

City,

Shin-Kawasaki,

Architectural

Product

Engineering,

No.

263, pp.23-32,

租骨材の特性が超高強度コンクリートの力学的性質に及ぼす影響

【

】

・

Journal

，

．

，

J

，

．

，

．

，

EFFECTS

OF

COARSE

AGGR

．

EGATE

CHARACTERISTICS

．

ON

MECHANICAL

PROPERTIES

’

OF

ULTRA

HIGH

−

STRENGTH

CONCRETE

粗

骨材

特 性

超 高強 度

リ

ー

ト

力学 的性 質

及

す

影 響

’

Masa

11

IZAKI

Hidetoshi

EDAHfRO

柿 崎

正

義 ，枝 広 英 俊

This

kinds

400

kN

．

ive

deformation

high・

90

−

130

MPa

．

The

fol−

lows，

（

）

，

When

400

kN

is

11−

23

−

−

is

特性

超高強度

力学的性質

影響

柿崎

義，枝広英俊

　 This

_）

_（

_）

_（

_）

_，

_get