.SC1r
American SocietyiiFII
..
of Civil Engineers180 I ALEXANDER BELL DRIVE
RESTON, VIRGINIA 20191-4400
EDITED BY
Atorod Azizinamini
David Darwin
Catherine French
July 13-18
,
1997
Kona, Hawaii
SPONSOREDBY
United Engineering Foundation, Inc.
PROCEEDINGS
First
International Conference
Copyright @ 1999 by the American Society of Civil Engineers, All Rights Reserved. Library of Congress Catalog Card No: 99-17899 ISBN 0-7844-0419-4 Manufactured in the United States of America.
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$.50 per page. Requests for special permission or bulk copying should be addressed to Permissions & Copyright Dept., ASCE.Engineering Foundation Conference on High Strength Concrete (1S!: 1997: Kona, Hawaii) High strength concrete: first international conference: proceedings, July 13-18, 1997, Kona, Hawaii /sponsored by United Engineering Foundation, Inc.; edited by Atorod Azizinamini, David Darwin, Catherine French.
p. cm.
Includes bibliographical references. ISBN 0-7844-0419-4
1. High strength concrete-Congresses. 2. Concrete construction-Congresses. I. Azizinamini, Atorod. II. Darwin, David. III. French, Catherine (Catherine E.) IV. United Engineering Foundation (U.S.) V. Title.
TA439.E474 1997
624.1'834-dc21 99-17899
CIP Library of Congress Cataloging-in-Publication Data
Abstract: This proceedings,
High Strength Concrete,
consists of papers presented at the first Engineering Foundation Conference on High Strength Concrete, held July 13-18, 1997, in Kona, Hawaii. The conference brought together a group of individuals known for their contributions to high strength concrete (HSC); from material aspects to applications in the field. Since the 1980s, intense research activities have been conducted to resolve design issues related to the use of HSC. These papers explore such issues as the behavior of interior beam-and column subassemblages in a reinforced concrete frame, ductility and strength of HSC columns, shear strength of HSC beams, seismic behavior of prestressed concrete beam-column joints, crack growth and cyclic loads, and thermal performance of HSC.High Strength Concrete: Design Issues in the Canadian Code 582
Dents
MitchellCo
d
es
On Extending ACI318 to High Strength Concrete 5S4
Mohamed A.At. and Richard N.White
Provisions in U.S. Codes Related to nigh Strength Concrete 568
S.
K
.
GhoshVII
Use of CFRP Composites with High Strength Concrete in Bridges ...•... 391 Nabil F Grace. GCO'1lCAbdel-Sayed, and Michael S. Ledesma
Cracking in HighStrength Concrete at Early Ages...•...•.••... 401 Tor Arne Hammer. Erik J. Sellevold, and 0yvind Bjontegaard
Studying Initiation and Growth of Shear Cracks inReinforced Concrete
Bea
m
s
lsing Full-Field Digital Imaging.. _ .41
2
Daniel C Jansen. Sokhwan Choi, and Surendra P.ShahPenetration Resistance Tests on High Strength Concrete ...•...•....•...•....•.. ·U5
Sergio \.1 R
L
o
pes
and Miguel C.S. NcpomuccnoHigh Strength Concrete from Low Water Demand Cemenl. ....•...•... .434 J Moreno. Sh
r
Babaev, N.F Bashlykov, C. Eberhardt. B.E. Yudovich. andV.
R
Fali
k
rnan
Crack Gro» tb in Four Concretes under Monotonic or Cyclic Splitting Load .444
Kal
Duan and Jan G.M.van MierFundamental Aspects of Mechanical Behavior of
H
S/
HP
C
:
The EuropeanApproach 457
Jan G.M van Mier
Comparative 'tudy of High Strength Concrete Fracture Uniaxial and
Triaxial Loading _ 470
K
a
mran M
Nemati and Paulo J.M. MonteiroFiber Reinforced Higb Strength Concrete Beams in Shear .480 Kelvan xoghabai, Thomas 010fs50n, and Jonas Gustafsson
High Performance :\Ju!timodal Fiber Reinforced
C
e
m
e
nt
Composites(HP;\fFRCC) 494
P
ROSSI~1aterial Aspects of High Performance Concrete
50..
Surendra P
ShahThe L e of High Reactiv it) Mctakaolin in Higb Performance Concrete .517
\1D.A Thomas. K.A Gruber. and R.D. Hooton
Thermal Performance of Concretes Including High Strength Concrete S31 J.A. Tinker
Higb Strengtb Phosphate Cement Using Industrial By-Product Ashes S42
·us
As
a way of estimating the "in situ" strength for high strength concrete, some techniques, previously used in normal strength concrete, have been adapted and The interest of high strength concrete has increased considerably in the last lew years. Several research works on this subject have contributed to a better understanding of the material properties and mechanical behavior in structural elements ofhigh strength concrete.One subject, which needs some investigation as far as the use of high strength concrete In building construction is concerned, is the prediction of "in situ' concrete strength. It is known that the strength measured on standard specimens, at 28 days and cured in standard conditions, only gives the potential value of the concrete strength, which is useful for quality control purposes and for checking the acceptability of the concrete as it is produced (1.
2).
However, this reference strength is normally achieved by the real structure at ages much higher than 28 days, depending on various parameters, mostly associated with curing conditions. On the other hand it is often necessary to know the strength of concrete before 28 days to determine when the forms can be disassembled or to know the structure peliormance at certain age.INTRODUCTION
The aim of the investigation described here is to verify the applicability of penetration resistance tests on high strength concrete as a way of estimating its compressive strength "in situ". A relationship between compressive strength of a given concrete and its resistance to penetration by a steel probe fired into the concrete surface is presented to a compressive strength range varying from 50 MPa to 90 MPa using an alternative firing apparatus to the standard apparatus Windsor Probe Test System.
ABSTRACT
Miguel C. S. Nepomuceno Lecturer
University of Beira Interior Dep. of Civil Eng.
6200 Covilha - Portugal Sergio M. R.Lopes
Assistant Professor University of Coimbra Dep. of Civil Eng. - FCTUC 3049 Coimbra Codex - Portugal
PENETRATION RESISTANCE TESTS ON
HIGH STRENGTH CONCRETE
The way of delivering the energy to the probe by
t
he A
l
temative Firing Appa
r
atus
has littl
e
difference from the
W
PT System previously mentioned
.
Bo
t
h sys
t
ems use
a po
w
der cartridge and probes, but
w
hile in the first apparatus I;NPT System)
d
e
tonation resu
l
tant energy of the powd
e
r cartridge is transmitted d
i
rectl
y
to
t
he
probe
,
which Is accele
r
a
t
ed and projected into the concrete surface, In the
Altemative FIring Apparatus this energy Is transmitted to a pis
t
on,
w
hich is projected
i
n high velo
ci
ty againstlhe probe
,
li
k
e a hammer
,
thrus
t
In the probe by the Impact.
A
l
t
e
rn
a
t
i
ve Fir
i
ng Apparatu
s
A test apparatus
,
designed for penetrat
i
on resistance measu
r
ements,
u
sing a
specia
l
probe and standardized po
w
de
r
charge,
w
as deve
l
oped In t
h
e US
A d
uring
the 1960s' and is kno
w
n as
W
indsor Probe Test System a
n
d covered by
t
he
A
ST
M
Standards (AST
M
-C803-90)
<a)
.
In Europe, similar s
t
andards are the British
Standards (BS 1881
:
Part 207
:
1992) (i). This system allo
w
s
t
he use of t
w
o
kin
ds of
probes:
t
he silver colored probe
,
t
o use
I
n co
n
cre
t
e
w
llh na
t
ural aggregate; and the
gold colored probe, to use with lightwe
i
ght co
n
crete. Two dif
f
e
r
en
t
power leve
l
s a
r
e
also posslole
,
using the same power
l
oad, by an adjustme
n
t
In
the instrumen
t
:
t
he
standard power and
l
ow power
.
For the purpose of this s
t
udy
,
I
t w
as decided
t
o use
the silver colored probe (of hardened steel alloy wi
t
h 6
.
35 mm diameter, 79
.
5 mm
leng
t
h, a b
l
unt conical end and a plastic guide) associated
w
ith the standard po
w
er.
Probes were fired into concrete, using
t
he driver unit, and t
h
e exposed le
n
g
t
h
w
as
measured Individually, by using a rectangu
l
ar p
l
a
t
e
,
placed over p
r
obe and
pressured agains
t
the concrete by a knurted spring-nut, and a measuring cap
threaded on top of probe
.
The distance
w
as measured
f
rom
t
op of cap to plate
w
i
t
h
the micrometer depth gauge
.
W
i
ndsor Pr
o
be T
es
t System
TEST EQUIPMENT
In an attempt to use
W
indsor Probe Test S
y
stem in
hi
gh strength conc
r
e
t
e,
pertormed by the authors
,
it
w
as foun
d
tha
t
the available
pr
ob
e
s and/or t
h
e
p
o
w
er
level are unsuitable; probes didn't pene
t
rate the co
n
crete surtace. I
t
means tha
t
probab
l
y a new probe and/or a ne
w
po
w
er leve
l
has
t
o be pro
v
ided by manufacturer
in order to be possible i
t
s use in high stre
n
gth conc
r
ete.
On the present i
n
vestigation
t
he possibility of us
i
ng a
n
a
l
temati
v
e firing a
p
para
tu
s
t
o
the traditiona
l W
indsor P
r
obe Test System
w
as e
v
aluated fo
r th
e ra
n
ge o
f
concrete
compressive strengt
h
varyi
n
g
f
rom 50
M
Pa to 90
M
Pa
.
A
p
r
e
v
ious study, comparing
the reliability of bo
t
h appara
t
us, Is a
l
so presented for
th
e
r
ange of co
n
c
r
ete
compressive strength up to 50
M
Pa.
used. One of those tech
n
iques cons
i
s
t
s on
ca
l
ibratin
g a
rel
ations
hi
p be
twe
e
n th
e
compressive strength
of a
gi
ven
conc
ret
e
and
its r
e
sis
ta
nce
to pene
tration b
y a s
t
e
el
probe
f
i
r
ed in
t
o the co
n
crete surtace. T
hi
s test, genera
ll
y
kn
o
wn
as
W
indso
r P
robe
Test System
,
has o
n
ly s
h
own its applicabil
i
ty in conc
r
e
t
es i
n wh
ich strengths are
n
o
more than 50
M
Pa (measuredIn cubes o
f
150 mm).
HIGH STRENGTHCONCRETE
The specimens
w
ere cured together at approximately 1~C and relative humidity of
65%.
A
ll the tests were performed at 28 days age lor each group of specimens and,
at the time o
f
testing
,
the specimencondition was dry.
Five differen
t
mix propo
rt
ions, cor
r
espondingto five different c
l
asses of compression
st
r
ength,
w
e
r
e produced in order
t
o obtain five sets of specimens, each one
comprising a 750x550x
1
70 mm slab and 4 cubes o
f
150 mm, all obtained by using
metallic
m
oulds
.
Each slab
w
as co
n
struc
t
ed to
w
i
t
hstand S tests of
W
PT System
and, at least, 12 tests by the
Alt
emative Firing Appara
t
us
.
The dimensions were
determined in order
t
o obtain
,
l
or standard power, the recommended edge
distances
,
member thickness and minimum dista
n
ces bet
w
een tests, given by
AST
M
standards
(a),to preven
t
splitting of
t
he member under tes
t
, structural
crackinga
n
d a
l
so to avoid overlapping 01 zones 01 inlluence
.
The mix proportions were estab
l
ished In order to fix the maximum number of
parameters.
Th
erefore,
t
he Faury modules of fineness remained exact
l
y the same
and the workability of fresh concrete
,
measured by slump test
,
was fixed between
80 mm and 120 mm.
Al
so the operations of mixing and compacting (type and
frequency)were kept cons
t
an
t
In all
t
he cast specimens.
The coarse aggregates were crushed rock from granite with
t
he max
i
mum
dimension of 25.4 mm and a Mohs
'
hardness scale level 7
.
The fine aggregate was
a natu
r
a
l
sa
n
d
f
rom the river
.
In a pre
v
ious study o
n
normal st
r
ength concrete, performed b
y t
he au
t
hors ~),
t
he
possibili
t
y of using a
n
a
lt
emative
f
iring apparatus to the traditional
W
indsor Probe
Tes
t
System
w
as evaluated
.
Prev
i
ous Studies on Normal Strength Concrete
PROCEDURE
In bo
t
h cases
t
he exposed lengt
h w
as direct
l
y measured, by using a depth gauge,
relatively
t
o the original surface of the concrete.
For high streng
t
h conc
r
ete,
t
he probe
w
as made of steel alloy with 4.5 mm diameter
a
nd
42.0 mm length, a conical end an
d
a plastic guide
.
The powder charge
w
as
l
evel 7
.
T
he probe used for normal st
r
e
n
gth co
n
crete
w
as made of s
t
eel alloy
w
iltl 4.5 mm
dia
m
e
t
er and 52
.
0 mm
l
e
n
gth, a conical end and a plastic guide
.
The po
w
der charge
w
as
l
evelS.
The
A
ltemat
iv
e
F
iring
A
p
p
aratusenables the control
o
f the energy leve
l
, delivered to
the probe by
t
he driver, as well as dif
f
erent dime
n
sions and geometries
f
or the
p
r
obe.
4
27
I
g
h
i
i
Sand (ko)
802
755
660
549
422
Coarse agg.l (kg)
241
306
399
401
503
Coarse aoo.2(ko)
730
708
670
732
716
Cement (kg)
400
425
485
535
600
Admixture
(I)10
.
0
10
.
6
12.1
13.4
15
.
0
Water!l)
142
140
1
4
5
145
157
WIC
0
.
36
0
.
33
0
.
30
0
.
27
0
.
26
T
a
b
le
1
- Basic m
i
x proportions per cubic meier
For concrete mix proportions a water
/
cement relationship based on we
i
ght varying
from 0.36 to 0.26 was considered in order to obtain the compresstve strength
between 50 MPa and 90 MPa. The cement quantity varied from 400 kg to 600 kg
per cubic meter and the workability
,
measured by slump lest
,
remained between 60
and 100 mm
.
The live basic mix proport
i
ons are presented on Table 1.
The fine aggregate is nalural sand from
t
he river
w
ith a fineness modulus about 3.5
and the coarse aggregates is a crushed rock from granite supplied with
two
gradations, classified as coarse aggregate 1 and coarse aggregate 2, with a
maximum dimension of 25.4 mm and a Mohs
'
hardness scale level 7
.
As for normal strength concrete, mix proportions were determined
i
n order to keep
constant the maximum number of parameters, such as, Faury modules of
f
ineness,
workability and the operations of mixing and compacting.
Among the types of cement available in Portugal
,
a normal portland cement
,
type I,
class 42.5R
,
class
i
fied accordingto the Portuguese Norms NP2064, was chosen.
Considering the desirable level of strength and concre
t
e producing conditions, a
superplasticizer was selected which was highly concentrated and based on
synthetic resins without air-enlraining agents. This superplastiCizerenabled a water
reduction of about 22%, keeping the same workabili
t
y.
Five different mix proportions were produced with constituent materials of the same
characteristics, which allows five different classes of compression strength between
50 MPa and 90 MPa
.
From each batch 3 standard cubes of 150 mm were produced
as well as one prismatic slab with dimensions 550x50Ox170mm
.
Studies
o
n H
ig
h Stre
n
gth Con
cr
ete
The Altemative Firing Apparatus
was
studied in order to find out its suitability and
reliability for normal strength concretes and good results were obtained. Therefore
the same study was applied to high strength concrete
w
hich is explained in this
paper.
HIGHSTRENGTH CONCRETE
The results presented on the above Table 2 were analyzed and plotted individually for both apparatus used, as shown in Fig. 1 and Fig.2.
a b c
d
eCubes of 150 mm fem[MPa] 17.70 23.80 37.43 42.33 53.18
cured at 1211C, (4) (3) (4) (4) (4)
R.H. 65%, tested SOX [MPa) 0.47 2.62 0.87 1.74 1.94 drv, at 28 days CVI%] 2.66 11.00 2.32 4.11 3.65 Penetration Test E (mm] 39.14 43.59 51.52 52.97 54.70 Resistance by (6) (6) (6) (6) (5) WPT System SOX [mmJ 3.34 1.54 1.65 1.64 2.34 CV 1%1 8.53 3.53 3.20 3.10 4.27 Penetration Test E [mm] 16.40 19.82 24.53 25.08 26.92 Resistance by (17) (13) (12) (13) (17) the Altemative SOX [mmJ 1.40 0.85 1.65 0.80 1.13 Firina Apparatus CVI%l 8.54 4.29 6.73 3.19 4.20
Table 2 -Results obtained for normal strength concrete (Number in parenthesis shows the number of measurements).
Ets the mean value ofthe exposure length.
femis the mean value of compressive strength on standard cubes.
Both apparatus were simultaneously used on the same concrete and the obtained experimental results are shown In Table 2.
Previous Studies on Normal Strength Concrete ANALYSIS OF RESULTS
All specimens (slab and cubes) were cured in water at controlled temperature of 2()!!C±2!!C and ali the tests were performed at 28 days. For each batch, 3 cubes were tested for compression strength and penetration resistance tests applied on concrete slab surface by using the "Altematlve Firing Apparatus". All specimens were wet at the time oftesting.
4
29
HIGH STRENGTH CONCRETEFig. 2 - Results obtained from theAltemative Firing Apparatus lor normal strength concrete.
60
~L TERN~ TIVE FIRINQ AEP~BAI!.!S
:;
0)c
(Il....
~ 50-
VIa.as
~~.
2j
E
(iii) tem=·37.5+
3.2101 • E!!!
0.co
,a. -
_
\
,/
<;
E VI8~
- a
0 30 (Il"e,
,
'
.:2~ """as c
>
as
20(Iv)
fem= 3.1772 • EXP(0.1 02926 • E)c-as
VI (Il C ~ 010
16 18 20 22 24 26 28Mean value of exposure length E [mm)
Fig. 1-Results obtained from the Windsor Probe Test for normal strength concrete. Mean value of exposure length E[mm)
45 50 55 40
104----.----~---r----~--,_--~----,_--~
(if)
f
e
m
= 1.31038 • EXP (0.06627S·E)(i)
tern
= - 64.929+
2.06301 • E\_
,,///
~
/'•
WINDSOR PROBE TEST SYSTEM
HIGH STRENGTH CONCRETE
Fi
g
.
3 - Results obtained
I
rom the
A
ltemati
v
e F
i
ring
A
pparatus fo
r
high streng
th
Concre
t
e
.
21
17 18 19 20
M
ean value 01 e
x
posure length E [mm)
16 £;
OJ
a5
ALTER
NA
TIVE FIRING APPAR
A
TUS
.:::(i 80
"'a.
~~.
_
~'"
~ 5
a. - 70E
<Ii8~
00
Q)'O .2 (ij 60 CIl '0(
v
)
'
em::
-
81
.
5344
+8
.
02508
•
E
> c:: ~~ Q)c
~ 0 50The obtained results (Table 3)
w
ere analyzed and p
l
otted as shown
i
n Fig
.
3
.
f
gh
I
I
Cubes o
f
150 rnm
'0m[
M
Pa)
4
9.12
58
.
27
67
.
77
7
8.35
8
1
.9
4
cured in
wat
er
(3)
(3)
(3)
(3)
(3)
at 20 !lC. tested
SOX [
M
Pal
1.02
0
.
82
1.56
2
.
17
1
.
12
w
et at 28 days
CV(
%
)
2.08
1.
4
1
2
.
30
2
.
77
1
.
37
Pene
t
ration Test
E [mm)
16
.
32
17
.
48
18.49
20.31
20.00
Resis
t
ance by
(10)
(9)
(
1
0)
(7)
(8)
t
h
e Alt
emati
v
e
SO
X (
mm}
0.92
0.97
1.64
0.56
0.8
7
Flri
nq A
pparatus
CV
(
%
1
5.64
5
.
50
8
.
87
2.7
6
4
.
35
T
able 3
- Resulls obtained for high strenglh concre
t
e
.
(Number In parenthesis shows the number of measurements)
.
E is the mean value 01the exposure length
.
l
em
Is the mean value of compressive s
t
rength on standard cubes
.
The
e
xperimental study on high strength concrete lead
t
o the
t
olowing results
presented on Table 3
.
S
t
udies
o
n
H
igh S
t
r
eng
t
h C
o
n
c
rete
411
(
1)
-
Yuan
,
Robert L
.
;
Ragab
,
Mostala
;
H
ill,
Robert E.
;
Cook
,
James E. - Evaluat
i
on
of Core Strength
i
n H
i
gh
-
Strength Concrete
,
Concrete Internati
o
nal
,
Vol. 13
.
pp 30
to
3
4
,
May 1991
.
(2) - Price
,
W. F
.
;
Hynes. J
.
P
.
-
I
n-s
i
tu Strength Test
i
ng of H
i
gh Strength Concrete.
Magazine of Concrete Research,48
,
N!l176
,
pp 189 to 197, Sept
1996
.
REFERENCES
E
- is the mean value of
the exposure length
.
f
em - I
s the mean value of compress
i
vestrength on standard cubes
.
SDX -
is the Standard deviation
.
CV
-
is
the Coeffic
i
ent of variation
.
R
.
H.
-
is the relative hum
i
dity
.
NOTATION
The authors
would like to thank the Univers
i
ty of Be
i
ra Interior for providing the
laboratory conditions and to
Mr. Armando
M
.
C
.
Trindade for h
i
s precious
collaboration
in the laboratory
works
.
They would like
to extend the
i
r thanks to the Univers
i
ty of Co
i
mbra and JNICT
research project ref.
PBIC/C/CEG/2384/95.ACKNOWLEDGMENTS
Other aspect that cannot be ignored
i
s the h
i
gher cost of WPT System equ
i
pment
and probes
in Europe when compared
w
i
th the Altemative Firing Apparatus
.
It is clear and mentioned by different authors (Q.
n
that. as most other
non-destructive
tests. aggregate characteristics and other factors may have a
considerable influence on the results and, therefore
,
the valid
i
ty of calibration tables
has to be carefully analyzed for each Situation.So
.
the results presented
on
Fig
.
1
.
Fig.
2 and
Fig
.
3 are valid for
the
established condit
i
ons of th
i
s
i
nvestigation
.
The main
physical limitation of penetration resistance
tests is
the surface damage
and the danger of splitting of members,which limits
the zones of testing. However. it
was found that the Altemative F
i
ring Apparatus causes less damage than
WPT
System
.
Consequently
,
m
i
nor distances between probes are possible
.
Penetration resistance tests applied to high strength concrete, using the
Altemative
Firing
Apparatus has shown
a linear correlation, Fig.
3.
which probably can be
impute to more closeness between cement paste and aggregate strength.
The results obta
i
ned for the range
o
f norma
l
strengt
h
concrete, Fig. 1 and Fig. 2,
showed that the A
lt
emat
i
ve Fi
rin
g Apparatus
co
uld be
a
suitable mean for the
assessment of "in-situ
·
strength, and gives a good agreement when compared to
Windsor Probe Test System
@
.
When testing high strength concrete (Fig. 3), the
Altemative Firing
Apparatus appears
to be
particularly useful since the results
obtained so far are very consistent.
CONCLUSIONS
HIGH STRENGTHCONCRETE 432
(3)
-
A
ST
M
Ca03-90
.
Standard
T
est
M
ethod for Pe
n
etration Res
i
s
t
a
n
ce of Harde
n
ed
Con
c
rete
.
American So
ci
ety for Testing and
M
ateria
l
s
.
(4) - BS 1881
:
Part 207
:
1992 - Recommendat
i
onsfor
t
he assess
m
en
t
of concrete
strength by near
-
to
-
surface
t
ests
.
British Standards Institutio
n
,
L
ondon
.
(
5
)
- Lopes
,
Serg
io;
Nepomuceno,
M
iguel
-
A Compa
r
a
t
i
v
e S
tu
d
y
of Penetration
Resistance Apparatus on Concrete
,
ICCEJ
4
,Ha
w
aii
,
Ju
1
1997
.
(
6
) -
Bungey
,
J. H. - Testing by Pene
t
ra
ti
on Resis
t
ance - Concre
t
e,
V
ol. 15,
N
il
1
,
Jan
.
1981
,
pp 30 to 32.
(7)
-
Bungey
,
J. H
.;
M
illard
,
S. G
.
-
Testing of Co
n
crete in
St
ructures
,
3 ed
.,
Chapman
&Hall
,
London - UK.
,
1996.
433
