This investigation studies the behavior of surface wave velocity in concrete specimens subjected to low levels of compressive and tensile stress in beams from applied flexural loads. Beam specimen is loaded in a 4-point-load bending configuration, generating uniaxial compression and tension stress fields at the top and bottom surfaces of the beam, respectively. Surface waves are generated through contactless air-coupled transducers and received through contact accelerometers. Results show a clear distinction in responses from compression and tension zones, where velocity increases in the former and decreases in the latter, with increasing load levels. These trends agree with existing acoustoelastic literature. Surface wave velocity tends to decrease more under tension than it tends to increase under compression, for equal load levels. It is observed that even at low stress levels, surface wave velocity is affected by acoustoelastic effects, coupled with plastic effects (stress-induced damage). The acoustoelastic effect is isolated by means of considering the Kaiser effect and by experimentally mitigating the viscoelastic effects of concrete. Results of this ongoing investigation contribute to the overall knowledge of the acoustoelastic behavior of concrete. Applications of this knowledge may include structural health monitoring of members under flexural loads, improved high order modelling of materials, and validation of results seen in dynamic acoustoelasticity testing.

1.
J.L.
Rose
,
Ultrasonic Waves in Solid Media
(
Cambridge
,
University Press
,
1999
).
2.
A.N.
Guz
and
F.G.
Makhort
,
The Physical Fundamentals of the Ultrasonic Nondestructive Stress Analysis of Solids
,
International Applied Mechanics
, vol.
36
(
9
),
2000
, pp
1119
1149
.
3.
A.
Chen
and
T.
Schumacher
, “
Estimation of In-situ Stresses in Concrete Members using Polarized Ultrasonic Shear Waves
” in
AIP Conference Proceedings
, vol.
1581
,
2014
, pp
903
908
.
4.
R.
Ellwood
,
T.
Stratoudaki
,
S.D.
Sharples
,
M.
Clark
, and
M.G.
Somekh
, “
Determination of the Acoustoelastic Coefficient for Surface Acoustic Waves using Dynamic Acoustoelastography: an Alternative to Static Strain
” in
Journal of the Acoustical Society of America
, vol.
135
(
3
),
2014
, pp
1064
1070
.
5.
J.N.
Eiras
,
Q.A.
Vu
,
M.
Lott
,
J.
Payá
,
V.
Garnier
,
C.
Payan
, “
Dynamic Acousto-elastic Test Using Continuous Probe Wave and Transient Vibration to Investigate Material Nonlinearity
” in
Ultrasonics
, vol.
69
,
2016
, pp
29
37
.
6.
Lillamand
,
J.F
Chaix
,
M.A.
Ploix
, and
V.
Garnier
, “
Acoustoelastic Effect in Concrete Material Under Uni-axial Compressive Loading
” in
NDT and E International
, vol.
43
(
8
),
2010
pp:
655
660
.
7.
F.G.
Makhort
,
O.I.
Gushcha
, and
A.A.
Chernoochenko
, “
Theory of acoustoelasticity of Rayleigh Surface Waves
” in
Soviet Applied Mechanics
, vol.
26
(
4
),
1990
, pp
346
350
.
8.
G.A.
Rogerson
and
J.G.
Murphy
, “Surface Waves in Elastic Compressible, Finitely Deformed Elastic Media,” in
Mechanics Research Communications
, vol.
25
(
5
),
1998
, pp
493
502
.
9.
P.
Shokouhi
,
A.
Zoega
,
H.
Wiggenhauser
, and
G.
Fischer
, “
Surface Wave Velocity-Stress Relationship in Uniaxially Loaded Concrete
” in
ACI Materials Journal
, vol.
109
(
2
),
2012
, pp
141
148
.
10.
C.
Payan
,
V.
Garnier
, and
J.
Moysan
, “Determination of Third Order Elastic Constants in a Complex Solid Applying Coda Wave Interferometry”, in
Applied Physics Letters
, vol.
94
(
011904
),
2009
, pp
1
2
.
11.
P.
Lundqvist
and N Rydèn, “
Acoustoelastic Effects on the Resonance Frequencies of Prestressed Concrete Beams—Short-Term Measurements
” in
NDT and E International
, vol.
50
,
2012
, pp
36
41
.
12.
Y.
Zhang
,
O.
Abraham
,
F.
Grondin
,
A.
Loukili
,
V.
Tournat
,
A.
Le Duff
,
B.
Lascoup
, and
O.
Durand
, “
Study of Stress-Induced Velocity Variation in Concrete Under Direct Tensile Force and Monitoring of the Damage Level by Using Thermally-Compensated Coda Wave Interferometry
” in
Ultrasonics
, vol.
52
,
2012
, pp
1038
1045
.
13.
D.S.
Hughes
and
J.L.
Kelly
, “
Second-Order Elastic Deformation of Solids
” in
Physical Review
, vol.
92
(
5
),
1953
, pp
1145
1149
.
14.
T.
Berruti
and
M.M.
Gola
, “
Acoustoelastic Determination of Stresses in Steel Using Rayleigh Ultrasonic Waves
” in
Materials Science Forum
, vols.
210-213
,
1996
, pp
171
178
.
15.
P.
Shokouhi
,
A.
Zoega
, and
H.
Wiggenhauser
, “
Nondestructive Investigation of Stress-Induced Damage in Concrete
”,
Advances in Civil Engineering
, vol. Article ID
740189
,
9
pages,
2010
.
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