JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 52
health monitoring
Strain measurements and damage detection
by fibre optics sensors in large structures
By means of a novel and robust automated technique based on strain field pattern recognition, a
defect detectability study was performed for two
13.5-metre-long wind turbine blade prototypes
under different load scenarios. Fibre optic sensors
(FOS) were embedded into the blades (fully made
of composite materials) during the manufacturing
process, which consisted in an experimental RTM
light procedure. Two different FOS technologies
were used: fibre Bragg gratings (FBGs) and distributed sensing by means of an optical backscatter
reflectometer (OBR). Some challenges associated with the integration of the sensor within the
structure had to be faced in order to guarantee
the appropriate operation of the sensors network
during the service life of the blades (in this case,
during the experiments). Several static tests were
conducted, including a test campaign in a wind turbine test laboratory with known artificial damages
induced into the structure, and the sensitivity of
the technique was evaluated. The results showed
that each damage could be detected using both
sensing techniques.
T
he integrity and reliability of structures are extremely important in many engineering fields like aeronautics, space,
civil engineering, architecture and energy, among others.
They are controlled through adequate knowledge of existing
damages. Typically, achieving the level of knowledge necessary
to characterize structural integrity involves the usage of nondestructive testing techniques (NDT), which are often expensive
and time consuming.
Need for health monitoring
As the complexity of structures increases, so do the physical and/
or mathematical models that describe such structures as well as
the techniques used to ensure their structural integrity during
their service life. Nowadays, several structural health monitoring (SHM) techniques for determining at an early stage whether
a structure is damaged are being developed by diverse research
groups around the world. One of the proposed "philosophies"
consists in building models based on information (experimental
data). This current has been called data-driven models (DDM)
and employs experimental data instead of deterministic models
(such as the stiffness matrix, modal parameters, etc.). Experimental data are used for "training" or "learning" of different types of
algorithms. The technique has been called "pattern recognition".
Thanks to their high strength-to-weight ratios, corrosion
resistance, fatigue performance, high stiffness and many other
advantages over conventional metallic materials, composite
materials are increasingly used in aerospace structures. However,
composite materials present some uncertainties and limitations
from the reliability perspective and, therefore, the development
of techniques which allow replacing the current schedule-based
maintenance of damage-tolerant composite structures by condition-based maintenance would allow improving the durability
and safety of structures.
In recent years, several authors have been working on the development of SHM techniques in order to predict the onset of damage in complex structures made of composite materials.
By
Strain measurement methodology
Dr. Julián Sierra-Pérez
aSSociate ProfeSSor
aeroSPace engineering reSearch grouP
univerSiDaD Pontificia Bolivariana
52 jec composites magazine / No96 April 2015
A novel methodology for damage detection in structures is
proposed. The methodology is based on strain measurements
and consists in the development of strain field pattern recognition techniques. The changes in the local strain field may be very
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015
Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #96 - April 2015
Cover
Edito
Point of view : composites integration
Contents
COMPANY & BUSINESS
China
In brief
JEC Americas
Agenda of Events
APPLICATIONS
Catamaran
RIB
Trimaran
MARKET
Carbon fibre
FEATURE AERONAUTICS
Simulation
Cost-effectiveness
Low cost manufacturing
Thin-ply
High temperature
LFT
Thermoplastics
Laser projection
Release agent
Manufacturing
RESEARCH & DEVELOPMENT
Health Monitoring
Health monitoring techique for large composite structures
TECHNOLOGY & INNOVATIONS
IOT
Braiding
Resin
Vacuum infusion
Machining center
PBT
Index
In the world
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Cover
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 2
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Edito
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Point of view : composites integration
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 5
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Contents
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 7
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - China
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - In brief
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - JEC Americas
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 11
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 12
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 13
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Agenda of Events
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 15
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Catamaran
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 17
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - RIB
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Trimaran
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 20
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Carbon fibre
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 22
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 23
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 24
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 25
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Simulation
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 27
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Cost-effectiveness
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 29
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Low cost manufacturing
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 31
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 32
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Thin-ply
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 34
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 35
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - High temperature
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 37
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - LFT
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 39
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 40
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Thermoplastics
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 42
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 43
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 44
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Laser projection
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 46
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Release agent
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Manufacturing
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 49
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 50
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 51
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Health Monitoring
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 53
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 54
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 55
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Health monitoring techique for large composite structures
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 57
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 58
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 59
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - IOT
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 61
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Braiding
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 63
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 64
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Resin
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 66
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Vacuum infusion
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 68
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Machining center
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 70
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 71
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - PBT
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - Index
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - In the world
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 75
JEC COMPOSITES MAGAZINE - Issue #96 - April 2015 - 76
https://www.nxtbook.fr/newpress/jeccomposites/jcm2211_148
https://www.nxtbook.fr/newpress/jeccomposites/jcm2209_147
https://www.nxtbook.fr/newpress/jeccomposites/jcm2206_146
https://www.nxtbook.fr/newpress/jeccomposites/jcm2204_145
https://www.nxtbook.fr/newpress/jeccomposites/jcm2201_144
https://www.nxtbook.fr/newpress/jeccomposites/jcm211_143
https://www.nxtbook.fr/newpress/jeccomposites/jcm2109_142
https://www.nxtbook.fr/newpress/jeccomposites/jcm2107_141
https://www.nxtbook.fr/newpress/jeccomposites/jcm2105_140
https://www.nxtbook.fr/newpress/jeccomposites/jcm2103_139
https://www.nxtbook.fr/newpress/jeccomposites/jcm-experts-digest-additive-manufacturing-2020
https://www.nxtbook.fr/newpress/jeccomposites/jcm2101_138
https://www.nxtbook.fr/newpress/jeccomposites/jcm2011_Special_Issue4
https://www.nxtbook.fr/newpress/jeccomposites/jcm2011_137
https://www.nxtbook.fr/newpress/jeccomposites/jcm2009_136
https://www.nxtbook.fr/newpress/jeccomposites/jcm2007_135
https://www.nxtbook.fr/newpress/jeccomposites/jcm_2020_Q1_Innovation_Report
https://www.nxtbook.fr/newpress/jeccomposites/jcm2005_Special_Issue3
https://www.nxtbook.fr/newpress/jeccomposites/jcm2005_134
https://www.nxtbook.fr/newpress/jeccomposites/jcm2003_133
https://www.nxtbook.fr/newpress/jeccomposites/jcm2001_132
https://www.nxtbook.fr/newpress/jeccomposites/jcm1911_Special_Issue2
https://www.nxtbook.fr/newpress/jeccomposites/jcm1911_131
https://www.nxtbook.fr/newpress/jeccomposites/jcm1909_130
https://www.nxtbook.fr/newpress/jeccomposites/jcm1907_129
https://www.nxtbook.fr/newpress/jeccomposites/jcm1905_128
https://www.nxtbook.fr/newpress/jeccomposites/jcm1903_Special_Issue1
https://www.nxtbook.fr/newpress/jeccomposites/jcm1903_127
https://www.nxtbook.fr/newpress/jeccomposites/jcm1901_126
https://www.nxtbook.fr/newpress/jeccomposites/jcm1811_125
https://www.nxtbook.fr/newpress/jeccomposites/jcm1810_124
https://www.nxtbook.fr/newpress/jeccomposites/jcm1808_123
https://www.nxtbook.fr/newpress/jeccomposites/jcm1807_122
https://www.nxtbook.fr/newpress/jeccomposites/jcm1805_121
https://www.nxtbook.fr/newpress/jeccomposites/jcm1804_120
https://www.nxtbook.fr/newpress/jeccomposites/jcm1803_119
https://www.nxtbook.fr/newpress/jeccomposites/jcm1802_119-Supplement_Innovation_Report
https://www.nxtbook.fr/newpress/jeccomposites/jcm1801_118
https://www.nxtbook.fr/newpress/jeccomposites/jcm1711_117
https://www.nxtbook.fr/newpress/jeccomposites/jcm1710_116
https://www.nxtbook.fr/newpress/jeccomposites/jcm1708_115
https://www.nxtbook.fr/newpress/jeccomposites/jcm1707_114
https://www.nxtbook.fr/newpress/jeccomposites/jcm1706_113
https://www.nxtbook.fr/newpress/jeccomposites/jcm1704_112
https://www.nxtbook.fr/newpress/jeccomposites/jcm1703_111
https://www.nxtbook.fr/newpress/jeccomposites/jcm1701_110
https://www.nxtbook.fr/newpress/jeccomposites/jcm1611_109
https://www.nxtbook.fr/newpress/jeccomposites/jcm1610_108
https://www.nxtbook.fr/newpress/jeccomposites/jcm1608_107
https://www.nxtbook.fr/newpress/jeccomposites/jcm1607_106
https://www.nxtbook.fr/newpress/jeccomposites/jcm1605_105
https://www.nxtbook.fr/newpress/jeccomposites/jcm1604_104
https://www.nxtbook.fr/newpress/jeccomposites/jcm1603_103
https://www.nxtbook.fr/newpress/jeccomposites/jcm1601_102
https://www.nxtbook.fr/newpress/jeccomposites/jcm1511_101
https://www.nxtbook.fr/newpress/jeccomposites/jcm1510_100
https://www.nxtbook.fr/newpress/jeccomposites/jcm1509_99
https://www.nxtbook.fr/newpress/jeccomposites/jcm1507_98
https://www.nxtbook.fr/newpress/jeccomposites/jcm1505_97
https://www.nxtbook.fr/newpress/jeccomposites/jcm1504_96
https://www.nxtbook.com/newpress/jeccomposites/jcm1503_95
https://www.nxtbook.com/newpress/jeccomposites/jcm1501_94
https://www.nxtbook.com/newpress/jeccomposites/jcm1412_93
https://www.nxtbook.com/newpress/jeccomposites/jcm1410_92
https://www.nxtbook.com/newpress/jeccomposites/jcm1409_91
https://www.nxtbook.com/newpress/jeccomposites/jcm1406_90
https://www.nxtbook.com/newpress/jeccomposites/jcm1405_89
https://www.nxtbook.com/newpress/jeccomposites/jcm1404_88
https://www.nxtbook.com/newpress/jeccomposites/jcm1403_87
https://www.nxtbook.com/newpress/jeccomposites/jcm1401_86
https://www.nxtbook.com/newpress/jeccomposites/jcm1311_85
https://www.nxtbook.com/newpress/jeccomposites/jcm1310_84
https://www.nxtbook.com/newpress/jeccomposites/jcm1308_83
https://www.nxtbook.com/newpress/jeccomposites/jcm1307_82
https://www.nxtbook.com/newpress/jeccomposites/jcm1305_81
https://www.nxtbook.com/newpress/jeccomposites/jcm1304_80
https://www.nxtbook.com/newpress/jeccomposites/jcm1303_79
https://www.nxtbook.com/newpress/jeccomposites/jcm1301_78
https://www.nxtbook.com/newpress/jeccomposites/jcm1212_77
https://www.nxtbook.com/newpress/jeccomposites/jcm1210_76
https://www.nxtbook.com/newpress/jeccomposites/jcm1208_75
https://www.nxtbook.com/newpress/jeccomposites/jcm1207_74
https://www.nxtbook.com/newpress/jeccomposites/jcm1206_73
https://www.nxtbook.com/newpress/jeccomposites/jcm1204_72
https://www.nxtbook.com/newpress/jeccomposites/jcm1203_71
https://www.nxtbook.com/newpress/jeccomposites/jcm1201_70
https://www.nxtbook.com/newpress/jeccomposites/jcm1111_69
https://www.nxtbook.com/newpress/jeccomposites/jcm1110_68
https://www.nxtbook.com/newpress/jeccomposites/jcm1108_67
https://www.nxtbook.com/newpress/jeccomposites/jcm1107_66
https://www.nxtbook.com/newpress/jeccomposites/jcm1105_65
https://www.nxtbook.com/newpress/jeccomposites/jcm1104_64
https://www.nxtbook.com/newpress/jeccomposites/jcm1103_63
https://www.nxtbook.com/newpress/jeccomposites/jcm1101_62
https://www.nxtbook.com/newpress/jeccomposites/jcm1011_61
https://www.nxtbook.com/newpress/jeccomposites/jcm1010_60
https://www.nxtbook.com/newpress/jeccomposites/jcm1009_59
https://www.nxtbook.com/newpress/jeccomposites/jcm1006_58
https://www.nxtbook.com/newpress/jeccomposites/jcm1005_57
https://www.nxtbook.com/newpress/jeccomposites/jcm1004_56
https://www.nxtbook.com/newpress/jeccomposites/jcm1003_55
https://www.nxtbook.com/newpress/jeccomposites/jcm1001_54
https://www.nxtbook.com/newpress/jeccomposites/jcm0911_53
https://www.nxtbook.com/newpress/jeccomposites/jcm0910_52
https://www.nxtbook.com/newpress/jeccomposites/jcm0909_51
https://www.nxtbook.com/newpress/jeccomposites/jcm0907-08_50
https://www.nxtbook.com/newpress/jeccomposites/jcm0906_49
https://www.nxtbook.com/newpress/jeccomposites/jcm0904_48
https://www.nxtbook.com/newpress/jeccomposites/jcm0903_47
https://www.nxtbook.com/newpress/jeccomposites/jcm0901_46
https://www.nxtbook.com/newpress/jeccomposites/jcm0811_45
https://www.nxtbook.com/newpress/jeccomposites/jcm0810_44
https://www.nxtbook.com/newpress/jeccomposites/jcm0809_43
https://www.nxtbook.com/newpress/jeccomposites/jcm0807_42
https://www.nxtbook.com/newpress/jeccomposites/jcm0806_41
https://www.nxtbook.com/newpress/jeccomposites/jcm0805_40
https://www.nxtbook.com/newpress/jeccomposites/jcm0803_39
https://www.nxtbook.com/newpress/jeccomposites/jcm0801_38
https://www.nxtbook.com/newpress/jeccomposites/jcm0712_37
https://www.nxtbook.com/newpress/jeccomposites/jcm0710_36
https://www.nxtbook.com/newpress/jeccomposites/jcm0709_35
https://www.nxtbook.com/newpress/jeccomposites/jcm0707_34
https://www.nxtbook.com/newpress/jeccomposites/jcm0706_33
https://www.nxtbookmedia.com