scispace - formally typeset
Search or ask a question
Journal Article•DOI•

Real-time structural health monitoring for concrete beams: a cost-effective ‘Industry 4.0’ solution using piezo sensors

Arka P. Ghosh, David J. Edwards, Mohammad Reza Hosseini, Riyadh Al-Ameri, Jemal H. Abawajy, Wellington Thwala 
05 May 2020-Vol. 39, Iss: 2, pp 283-311
TL;DR: This study merges industry 4.0 digital technologies with a novel low-cost and automated hybrid analysis for real-time structural health monitoring of concrete beams by fusing several multidisciplinary approaches into one integral technological configuration.
Abstract: Purpose: This research paper adopts the fundamental tenets of advanced technologies in industry 4.0 to monitor the structural health of concrete beam members using cost effective non-destructive technologies. In so doing, the work illustrates how a coalescence of low-cost digital technologies can seamlessly integrate to solve practical construction problems. Methodology: A mixed philosophies epistemological design is adopted to implement the empirical quantitative analysis of ‘real-time’ data collected via sensor-based technologies streamed through a Raspberry Pi and uploaded onto a cloud-based system. Data was analysed using a hybrid approach that combined both vibration characteristic based method and linear variable differential transducers (LVDT). Findings: The research utilises a novel digital research approach for accurately detecting and recording the localisation of structural cracks in concrete beams. This nondestructive low-cost approach was shown to perform with a high degree of accuracy and precision, as verified by the LVDT measurements. This research is testament to the fact that as technological advancements progress at an exponential rate, the cost of implementation continues to reduce to produce higher accuracy ‘mass-market’ solutions for industry practitioners. Originality: Accurate structural health monitoring of concrete structures necessitates expensive equipment, complex signal processing and skilled operator. The concrete industry is in dire need of a simple but reliable technique that can reduce the testing time, cost and complexity of maintenance of structures. This was the first experiment of its kind that seeks to develop an unconventional approach to solve the maintenance problem associated with concrete structures. This study merges industry 4.0 digital technologies with a novel low-cost and automated hybrid analysis for real-time structural health monitoring of concrete beams by fusing several multidisciplinary approaches in one integral technological configuration.

Summary (4 min read)

Jump to: [INTRODUCTION] – [STRUCTURAL HEALTH MONITORING OF CONCRETE MEMBERS] – [Sensor-based methods] – [Piezoceramic Sensors] – [RESEARCH PHILOSOPHY] – [Research Approach] – [Concrete member design] – [EXPERIMENT AND ANALYSIS DESIGN] – [Sensor Setup] – [Three-point bending test] – [FROM EXPERIMENTS TO FINDINGS] – [Test Beam 1 (control test)] – [THEORETICAL AND MANAGERIAL IMPLICATIONS] and [CONCLUSIONS]

INTRODUCTION

  • Indeed, over 25% of Canadian concrete bridges are deemed to be structurally deficient (Cusson et al., 2011), and 85% of high-rise buildings in New South Wales (NSW) built after 2000 had some form of structural failure (Randolph et al., 2019).
  • LVDT sensors will provide insufficient information regarding the cause of the observed displacement (Subramanian and Murugesan 2019), and microscopes can only observe and measure localised surface deformations without any indication of below surface deformations (Bernard 2019).
  • Researchers have also suggested the use of several forms of embedded and surface sensors in concrete to assess the concrete quality, economically (Taheri 2019b).

STRUCTURAL HEALTH MONITORING OF CONCRETE MEMBERS

  • Various methods for SHM are applied across the industry to observe, record and analyse physical changes to structural members throughout their lifecycle (Lynch et al., 2016).
  • Moreover, these methods are proven cumbersome with low efficacy and increasingly, are deemed impractical (Ghodoosi et al., 2018; Oesterreich and Teuteberg 2016).
  • Visual-based observation techniques such as the human eye, fibrescope, borescope, hand-held magnifier or stereo microscope are labour intensive and do not offer detailed or quantitative information about interior defects occurring internally within concrete members.
  • Acoustic techniques such as the rebound hammer, ultrasonic pulse velocity (UPV), impact echo, spectral wave analysis, crosshole sonic lagging or parallel seismic have various limitations.
  • Set against this contextual backdrop, a paradigm shift has occurred in the market, where new low-cost and highly accurate digital methods are designed based on including sensors that can be embedded internally in new structures or on the surface of already existing structures (Li et al., 2016).

Sensor-based methods

  • The contemporary concreting industry has progressively moved away from cumbersome SHM tools and techniques (Zinno et al., 2019).
  • As illustrated, most existing techniques are complex, expensive and operators require rigorous training to possess competency in these techniques.
  • This study proposes a novel technique with the help of a pilot study to address this research and provide industry with a viable accurate solution at an extremely affordable cost.
  • Low- cost piezoceramic sensors ($2.22 AUD each) and a raspberry pi model B 3+ ($54 AUD) as a controller are identified as a viable alternative package for monitoring the structural health of concrete members.

Piezoceramic Sensors

  • Piezoceramic sensors have been utilised heavily for SHM in the aircraft industry (Chang 2016; Shen et al., 2006), automobile (Martinotto et al., 2016) and manufacturing (Hossain et al., 2016) industries.
  • Water solubility and high humidity environments can affect the sensor (Mikulik and Linderman 2019).
  • Moreover, Dong et al., (2019) suggest that the use of piezoceramic sensors may affect the mechanical properties of the concrete structure when they are embedded.
  • That said, these barriers can readily be overcome with cost-effective techniques.
  • Yan et al. (2013), also embedded sensors into smaller sized concrete blocks to form a concrete smart aggregate and avoid physical damage that may occur to the delicate patches (where the latter may be damaged during curing of concrete members).

RESEARCH PHILOSOPHY

  • Whilst interpretavism (Roberts et al. 2019) informs the research direction and methods of measurement employed (via qualitative analysis of literature), positivism is employed to conduct quantitative analysis of empirical data (Edwards et al. 2019).
  • This combination of philosophies ensures that a scientifically robust research instrument is adopted.

Research Approach

  • When piezoceramic sensors are used to measure the mechanical properties of concrete, one of three common methods are often adopted: the impendence based method; the vibration characteristic based method; and the lamb-wave based method (Stojić et al., 2012).
  • This data is then correlated to strain displacements measurements collected by a LVDT electric strain gauge to assess crack detection and occurrence in four test sample members under various loading conditions.
  • For data analysis, signal processing techniques were adopted including Fourier transform (ul Haq et al., 2017), Hilbert-Huang transform (Wei et al., 2016) and wavelet analysis (Jain et al., 2016).
  • Fourier transform, Hilbert-Huang transform and wavelet analysis methods require extensive mathematical computation and signal processing.
  • Hence, for the purposes of this study, a simple hybrid analysis technique that correlates vibrational voltage feedback from piezoelectric elements and simple LVDT strain gauge displacements is adopted to facilitate easy adoption by industry practitioners.

Concrete member design

  • The beam will have 25 mm cover on all sides .
  • The mix-design and material composition of the M25 grade concrete members are provided in Table 1.
  • The Raspberry Pi microcontroller is a low cost, credit card-sized computer that plugs into a computer monitor or TV, and uses a standard keyboard and mouse, and uses much lesser power than other equivalent computing units (Raspberry Pi Foundation 2019).
  • The analogue to digital converter (ADC), is utilised to convert the analogue data received from the piezoceramic sensor into digital signals that are passed to the Raspberry Pi.

EXPERIMENT AND ANALYSIS DESIGN

  • The concrete mix components have been prepared, weighed, and dry mixed before adding the water using a lab scale mixer at Deakin’s concrete laboratory.
  • Then, the wet mix has been poured into the prepared moulds.
  • The piezoceramic sensors are then attached to the pre-determined locations on the surface of the beams .
  • One beam will be tested in flexure under three- point loading set up.
  • Furthermore, surface cracks were visually monitored and measured to use as further reference material when compari g several results.

Sensor Setup

  • Sensors were attached to each beam externally using adhesive tape to ensure optimised surface contact between the sensors and the concrete beam.
  • The final beam included five sensors where there were two on each of the front and rear faces and one on the base of the beam .
  • Setting up the sensors involved attaching the wiring by ensuring the male end of a wire was touching the exposed wire from the sensor and securing with tape.
  • Where the wire length previously connected to the sensors was not long enough, further extensions are attached ensuring that the length ends with a male connection point.
  • First, it was anticipated that because the sensors will collect data within a range of 20 – 50 mm, they were placed in the region of expected large damage on the beam.

Three-point bending test

  • The test is performed on the beams to achieve the ultimate flexural load.
  • This is the maximum transverse load and the corresponding bending moment that the beam can tolerate before full structural failure.
  • All outputs have been connected to a control panel and data acquisitioning system to capture the load-displacement relationship of each test.
  • Therefore, the piezoceramic sensors were attached towards the mid-section of the beam.
  • The materials have the property of generating an electric charge when subjected to a mechanical strain (direct effect for sensor) and conversely, generate a mechanical strain when subjected to an applied electric field (Taheri 2019b).

FROM EXPERIMENTS TO FINDINGS

  • Final testing was carried on once the entire setup was ready.
  • The beam was placed on the testing frame and ensuring that the marking were made in such a way that 13 sensors are connected to the correct location.
  • The load was gradually applied on the beams and the code was run at the start of loading and the loading on the beams continued till the specimen failed due to excessive deformation and concrete crushing.
  • Data streams from the piezoceramic sensors were collected for all four samples in SmartWorks platform with technical support provided by AltAir Solutions Company (Agarwal and Alam 2018).

Test Beam 1 (control test)

  • Beam 1 had 13 sensors attached on the surfaces when the load was applied.
  • At initial time instant, the voltage fluctuation of the sensors is ignored.
  • In fact the voltage spikes occur a few seconds before the surface cracks are observed on camera.
  • Also certain micro-cracks and internal cracks which cannot be registered on camera or even on a microscope are easily detected through the piezoceramic sensors through minor voltage spikes.
  • Similar tests are repeated for beams 2, 3, 4 respectively with similar displacement graphs obtained for the respective beams with the piezoceramic sensors detecting a spike in voltage at each of the major displacement spikes.

THEORETICAL AND MANAGERIAL IMPLICATIONS

  • The multidisciplinary approach (using Industry 4.0 advanced technologies) adopted towards solving an important maintenance issues associated with the construction industry has some significant theoretical and managerial implications.
  • Specifically, the work provides an economical and multi-featured addition to extant literature in the area of non-destructive testing (NDT) techniques (as outlined in Appendices 1 and 2).
  • The research presented therefore provides a useful case study of Industry 4.0 adoption and thus serves to generate wider polemic debate and discussion within the contemporary construction and civil e gineering management discipline.
  • Significant time savings (and by implication, cost savings) can be made in turnaround time required to obtain test results.
  • Enhanced transferability of data across the supply chain to better inform practitioners involved in the post-construction stages and assist decision making on maintaining concrete structures.

CONCLUSIONS

  • Many of these techniques suffer from the limitations of economic infeasibility or complex signal-processing techniques.
  • Presently this method has been used on large scale infrastructure projects or some critical projects (Park et al., 2003; Su et al., 2018).
  • The results of this study prove that piezoceramic sensors could detect both internal and external cracks and assist in real-time monitoring of concrete structures.
  • This study also serves as a real-life application of Industry 4.0 in the construction sector and consequently, reveals how technology can automated this process moving forwards.

Did you find this useful? Give us your feedback

Figures (8)

Content maybe subject to copyright    Report

International Journal of Building Pathology and Adaptation
REAL-TIME STRUCTURAL HEALTH MONITORING FOR
CONCRETE BEAMS: A COST-EFFECTIVE ‘INDUSTRY 4.0’
SOLUTION USING PIEZO SENSORS
Journal:
International Journal of Building Pathology and Adaptation
Manuscript ID
IJBPA-12-2019-0111.R3
Manuscript Type:
Original Article
Keywords:
Structural health monitoring, Industry 4.0, piezoceramic sensor,
concrete, Internet of things (IoT), Construction industry
International Journal of Building Pathology and Adaptation
International Journal of Building Pathology and Adaptation
Page 1 of 2
Ref: Manuscript ID IJBPA-12-2019-0111.R2
Journal: International Journal of Building Pathology and Adaptation
Title: Real-time structural health monitoring for concrete beams: a cost-effective ‘industry 4.0’
solution using piezo sensors
REVIEWERS’ COMMENTS AND AUTHORS’ RESPONSE
The authors wish to extend thanks to the referees once again for their constructive comments and
suggestions. These minor comments have now been addressed and a final file resubmitted for your
consideration using the ‘tracked changes’ feature within MS Word. Once again, thank you.
No.
Reviewer
Editor Comments
1
We are almost ready to accept your
manuscript for publication, however
there are a few minor points to be
addressed.
Referee No.1
2
Accept - The authors have certainly
made significant effort in addressing
some of the reviewer’s earlier comments,
and the quality of the manuscript has
significantly improved from the
‘originality’ and ‘contributions’
perspectives.
Referee No.2
3
The authors have made effort to improve
the paper, further change would be made
to expand the research implication
section and make sure the originality are
aligned with the research aims and
objectives.
4
The rationale of this research study is
interesting and meaning to the industry.
However, the solid explanations or
examples of its research implications are
neglect. The results and implications of
this research can be seen as practical.
More discussions on its implications on
theory and real work practices are looked
Page 1 of 39 International Journal of Building Pathology and Adaptation
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
International Journal of Building Pathology and Adaptation
Page 2 of 2
forward.
Page 2 of 39International Journal of Building Pathology and Adaptation
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
International Journal of Building Pathology and Adaptation
REAL-TIME STRUCTURAL HEALTH MONITORING FOR
CONCRETE BEAMS: A COST-EFFECTIVE ‘INDUSTRY 4.0’
SOLUTION USING PIEZO SENSORS
ABSTRACT
Purpose: This research paper adopts the fundamental tenets of advanced technologies in
industry 4.0 to monitor the structural health of concrete beam members using cost
effective non-destructive technologies. In so doing, the work illustrates how a
coalescence of low-cost digital technologies can seamlessly integrate to solve practical
construction problems.
Methodology: A mixed philosophies epistemological design is adopted to implement
the empirical quantitative analysis of ‘real-time’ data collected via sensor-based
technologies streamed through a Raspberry Pi and uploaded onto a cloud-based system.
Data was analysed using a hybrid approach that combined both vibration characteristic
based method and linear variable differential transducers (LVDT).
Findings: The research utilises a novel digital research approach for accurately
detecting and recording the localisation of structural cracks in concrete beams. This non-
destructive low-cost approach was shown to perform with a high degree of accuracy and
precision, as verified by the LVDT measurements. This research is testament to the fact
that as technological advancements progress at an exponential rate, the cost of
implementation continues to reduce to produce higher accuracy ‘mass-market’ solutions
for industry practitioners.
Originality: Accurate structural health monitoring of concrete structures necessitates
expensive equipment, complex signal processing and skilled operator. The concrete
industry is in dire need of a simple but reliable technique that can reduce the testing
time, cost and complexity of maintenance of structures. This was the first experiment of
its kind that seeks to develop an unconventional approach to solve the maintenance
problem associated with concrete structures. This study merges industry 4.0 digital
technologies with a novel low-cost and automated hybrid analysis for real-time
structural health monitoring of concrete beams by fusing several multidisciplinary
approaches in one integral technological configuration.
KEYWORDS
Page 3 of 39 International Journal of Building Pathology and Adaptation
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
International Journal of Building Pathology and Adaptation
Structural health monitoring, Industry 4.0, piezoceramic sensor, Internet of Things
(IoT), concrete, construction industry.
INTRODUCTION
Extant literature acknowledges the significance of implementing long-term structural
health monitoring (SHM) (Sheikh et al., 2016) systems for civil infrastructures, in order
to secure structural safety and issue incipient warnings of structural damage prior to
costly repair (Li et al., 2016). To underscore the scale of this operations and
maintenance activity, the concrete repair industry in the US is estimated to generate 25
billion USD per year (Al-Mahaidi and Kalfat 2018). Indeed, over 25% of Canadian
concrete bridges are deemed to be structurally deficient (Cusson et al., 2011), and 85%
of high-rise buildings in New South Wales (NSW) built after 2000 had some form of
structural failure (Randolph et al., 2019). SHM refers to a non-destructive process of
implementing a damage identification and diagnosis strategy (Sohn et al., 2003). In the
context of concrete members (cast in-situ or prefabricated), SHM refers to the detection
of abnormalities or deformities (i.e., arising via deterioration, damage or failure) and
provides information regarding structural health and integrity of concrete members for
continued use (Agarwal et al., 2017; Zou et al., 2019).
The structural health of concrete members relies on several factors, including
temperature (both external and internal), humidity, moisture content, applied stresses,
and boundary conditions during manufacturing and its life cycle (Strangfeld et al., 2017;
Tran et al., 2017). Structural members’ design normally takes these factors into
consideration (Ghodoosi et al., 2018). However, conditions are likely to change during
the service life of concrete members, with the potential to significantly affect the overall
health of the structure, providing the likelihood of deformations and failure (James et al.,
2019). Moreover, designers can implement little control over the external conditions
confronting concrete during its curing process (Joshi 2019; Moon et al., 2016).
In the current practice, several innovative and non-destructive methodologies have been
developed to address the above challenges, including c-scan (Liu et al., 2019); x-rays
(Marzec and Tejchman 2019); linear variable displacement transformers (LVDT)
(Mohandoss et al., 2019); conventional microscopes (Jang et al., 2019). The aim is to
identify and/or monitor structural deficiencies and cracks present in concrete structures
Page 4 of 39International Journal of Building Pathology and Adaptation
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Citations
More filters
Journal Article•DOI•
The Exposure of Workers at a Busy Road Node to PM2.5: Occupational Risk Characterisation and Mitigation Measures

[...]

Obuks Ejohwomu, Majeed Olaide Oladokun, Olalekan Shamsideen Oshodi, Oyegoke Teslim Bukoye, David J. Edwards, Nwabueze Emekwuru, O. A. Adenuga, Adegboyega Sunday Sotunbo, Ola Uduku, Mobolanle Balogun, Rose Alani 
01 Apr 2022-International Journal of Environmental Research and Public Health
TL;DR: In this paper , the authors assess the temporal variability of pollutants around the university environment to provide a novel comparative evaluation of occupational shift patterns and the use of facemasks as risk control interventions.
Abstract: The link between air pollution and health burden in urban areas has been well researched. This has led to a plethora of effective policy-induced monitoring and interventions in the global south. However, the implication of pollutant species like PM2.5 in low middle income countries (LMIC) still remains a concern. By adopting a positivist philosophy and deductive reasoning, this research addresses the question, to what extent can we deliver effective interventions to improve air quality at a building structure located at a busy road node in a LMIC? This study assessed the temporal variability of pollutants around the university environment to provide a novel comparative evaluation of occupational shift patterns and the use of facemasks as risk control interventions. The findings indicate that the concentration of PM2.5, which can be as high as 300% compared to the WHO reference, was exacerbated by episodic events. With a notable decay period of approximately one-week, adequate protection and/or avoidance of hotspots are required for at-risk individuals within a busy road node. The use of masks with 80% efficiency provides sufficient mitigation against exposure risks to elevated PM2.5 concentrations without occupational shift, and 50% efficiency with at least ‘2 h ON, 2 h OFF’ occupational shift scenario.

3 citations

Journal Article•DOI•
Accurate strength prediction models of ordinary concrete using early-age complex permittivity

[...]

Song Gao1, Kwok L. Chung2, Aiqi Cui1, Mohamed Ghannam3, Jianlin Luo1, Lingling Wang1, Mingliang Ma1, Zijian Liao1 •
Qingdao University1, Huizhou University2, Mansoura University3
01 Aug 2021-Materials and Structures
TL;DR: In this article, the compressive strength prediction models for ordinary concrete using early-age measurements of relative complex permittivity were presented, and the proposed models not only have high regression accuracy with R2-values of greater than 0.97 but also the low prediction errors of within 10%, which significantly outperform the existing models of the same kind.
Abstract: Early determination of correct cement dosage for concrete mixes and prediction of their compressive strengths are very valuable in construction industry. This article presents a few compressive-strength prediction models for ordinary concrete using early-age measurements of relative complex permittivity. Both the dielectric constant and loss factor of the first-seven-day concrete with four types of mix proportions were measured for building the mathematical models composed of exponential functions at 6 GHz, whereas the measured dielectric data at 28 d were used for model validations. The proposed models not only have high regression accuracy with R2-values of greater than 0.97 but also the low prediction errors of within 10%, which significantly outperform the existing models of the same kind. Through Cole–Cole plot analysis, this article reveals an interesting finding that a minimum loss factor was located at 3 GHz regardless of the age of concrete, which would be useful for wireless network design and planning inside a building. The average loss tangents of various concrete mixes have also been verified to have the same value (~ 0.33) regardless of concrete age, which explains the confidence in use of early-age dielectric properties. Moreover, this article also initiates a precise prediction method of using loss factor and dielectric constant simultaneously in a 3-dimensional plot, wherein no explicit mathematical model is required.

3 citations

Journal Article•DOI•
The Impact of Industry 4.0 Concepts and Technologies on Different Phases of Construction Project Lifecycle: A Literature Review

[...]

Julia Menegon, Luiz Carlos Pinto da Silva Filho
17 Dec 2022

2 citations

Book Chapter•DOI•
Detection and processing of real-time carotid pulse waves

[...]

Dipali Bansal
01 Jan 2021

1 citations

Journal Article•DOI•
Implementation of Digital Technologies in Construction Companies: Establishing a Holistic Process which Addresses Current Barriers

[...]

Peter Schnell, Phillip Haag, Hans Christian Jünger
27 Dec 2022-Businesses
TL;DR: In this article , the authors present a concept for a holistic digital-technology-implementation-process which addresses current barriers in the construction industry, namely Acceptance, Control and Competence.
Abstract: Digital technologies are being introduced in all areas of the construction industry with the overarching goals of increasing productivity while simultaneously simplifying work and reducing errors. Nevertheless, their use and the associated implementation in construction companies is currently still inhibited. One reason for this is the lack of a holistic implementation process for digital technologies. Therefore, the aim of this paper is to deliver a concept for such a holistic digital-technology-implementation-process which addresses current barriers. For this purpose, a qualitative literature analysis was conducted first, which reveals the current focus of research on digital technologies. In a second step, current barriers regarding the implementation of digital technologies were identified by conducting interviews with experts from German construction companies. The interview concept combined and adapted the survey instruments Technology Commitment by Neyer et al. and Technophobia by Sinkovics. Based on the findings of the qualitative literature research and the expert interviews, a holistic implementation process for the introduction of digital technologies for construction companies was developed, which specifically addresses the currently prevailing barriers. Therefore, the barriers Acceptance, Control and Competence were classified in a temporal context within the implementation process and recommendations for action are presented for the individual process steps of implementing digital technologies.

1 citations

References
More filters
Journal Article•DOI•
Overview of Piezoelectric Impedance-Based Health Monitoring and Path Forward

[...]

Gyuhae Park, Hoon Sohn, Charles R. Farrar, Daniel J. Inman
01 Nov 2003-The Shock and Vibration Digest
TL;DR: In this article, Niezrecki et al. summarized the hardware and software issues of impedance-based structural health modi- toring based on piezoelectric materials.
Abstract: In this paper we summarize the hardware and software issues of impedance-based structural health moni- toring based on piezoelectric materials. The basic concept of the method is to use high-frequency structural excitations to monitor the local area of a structure for changes in structural impedance that would indicate imminent damage. A brief overview of research work on experimental and theoretical stud- ies on various structures is considered and several research papers on these topics are cited. This paper concludes with a discussion of future research areas and path forward. Piezoelectric materials acting in the "direct" manner pro- duce an electrical charge when stressed mechanically. Con- versely, a mechanical strain is produced when an electrical field is applied. The direct piezoelectric effect has often been used in sensors such as piezoelectric accelerometers. With the converse effect, piezoelectric materials apply local- ized strains and directly influence the dynamic response of the structural elements when either embedded or surface bonded into a structure. Piezoelectric materials have been widely used in structural dynamics applications because they are lightweight, robust, inexpensive, and come in a variety of forms ranging from thin rectangular patches to complex shapes being used in microelectromechanical systems (MEMS) fabrications. The applications of piezoelectric mate- rials in structural dynamics are too numerous to mention and are detailed in the literature (Niezrecki et al., 2001; Chopra, 2002). The purpose of this paper is to explore the importance and effectiveness of impedance-based structural health mon- itoring from both hardware and software standpoints. Imped- ance-based structural health monitoring techniques have been developed as a promising tool for real-time structural dam- age assessment, and are considered as a new non-destructive evaluation (NDE) method. A key aspect of impedance-based structural health monitoring is the use of piezoceramic (PZT) materials as collocated sensors and actuators. The basis of this active sensing technology is the energy transfer between the actuator and its host mechanical system. It has been shown that the electrical impedance of the PZT material can be directly related to the mechanical impedance of a host structural component where the PZT patch is attached. Uti- lizing the same material for both actuation and sensing not only reduces the number of sensors and actuators, but also reduces the electrical wiring and associated hardware. Fur- thermore, the size and weight of the PZT patch are negligible compared to those of the host structures so that its attach- ment to the structure introduces no impact on dynamic char- acteristics of the structure. A typical deployment of a PZT on a structure being monitored is shown in Figure 1. The first part of this paper (Sections 2 and 3) deals with the theoretical background and design considerations of the impedance-based structural health monitoring. The signal processing of the impedance method is outlined in Section 4. In Section 5, experimental studies using the impedance approaches are summarized and related previous works are listed. Section 6 presents a brief comparison of the imped- ance method with other NDE approaches and, finally, sev- eral future issues are outlined in Section 7. 2. Theoretical Background

1,048 citations

Journal Article•DOI•
Understanding the implications of digitisation and automation in the context of Industry 4.0

[...]

Thuy Duong Oesterreich, Frank Teuteberg
01 Dec 2016-Computers in Industry
TL;DR: The results of the triangulation approach, which consists of a comprehensive systematic literature review and case study research, are presented, by illustrating a PESTEL framework and a value chain model, to present the implications of Industry 4.0 for the construction industry.

915 citations

Journal Article•DOI•
Hybrid fiber Bragg grating/long period fiber grating sensor for strain/temperature discrimination

[...]

Heather Patrick1, G.M. Williams2, Alan D. Kersey2, J.R. Pedrazzani, A.M. Vengsarkar •
United States Naval Research Laboratory1, United States Department of the Navy2
01 Sep 1996-IEEE Photonics Technology Letters
TL;DR: In this paper, the difference in strain and temperature response of fiber Bragg gratings and a long period fiber grating was used to discriminate between strain induced and temperature induced wavelength shifts.
Abstract: We demonstrate a novel sensor which uses the difference in strain and temperature response of fiber Bragg gratings and a long period fiber grating to discriminate between strain and temperature induced wavelength shifts. Sensor interrogation is performed entirely on the fiber Bragg grating reflection signals. Strain and temperature were simultaneously measured to /spl plusmn/9 /spl mu/strain and /spl plusmn/1.5/spl deg/C over a wide range of conditions.

546 citations

Journal Article•DOI•
Detection and monitoring of hidden fatigue crack growth using a built-in piezoelectric sensor/actuator network: I. Diagnostics

[...]

Jeong-Beom Ihn, Fu-Kuo Chang
01 Jun 2004-Smart Materials and Structures
TL;DR: In this paper, a piezoelectric-based built-in diagnostic technique has been developed for monitoring fatigue crack growth in metallic structures, which consists of three major components: diagnostic signal generation, signal processing and damage interpretation.
Abstract: A piezoelectric based built-in diagnostic technique has been developed for monitoring fatigue crack growth in metallic structures. The technique uses diagnostic signals, generated from nearby piezoelectric actuators built into the structures, to detect crack growth. It consists of three major components: diagnostic signal generation, signal processing and damage interpretation. In diagnostic signal generation, appropriate ultrasonic guided Lamb waves were selected for actuators to maximize receiving sensor measurements. In signal processing, methods were developed to select an individual mode for damage detection and maximize signal to noise ratio in recorded sensor signals. Finally, in damage interpretation, a physics based damage index was developed relating sensor measurements to crack growth size. Fatigue tests were performed on laboratory coupons with a notch to verify the proposed technique. The damage index measured from built-in piezoceramics on the coupons showed a good correlation with the actual fatigue crack growth obtained from visual inspection. Furthermore, parametric studies were also performed to characterize the sensitivity of sensor/actuator location for the proposed technique.

476 citations

Hybrid Fiber Bragg GratingLong Period Fiber Grating Sensor for S train/Temperature Discrimination

[...]

H. J. Patrick, G. M. Williams, A. D. Kersey, J. R. Pedrazzani, A. M. Vengsarkar 
01 Jan 1996

475 citations

Related Papers (5)
A Review of Machine Vision-Based Structural Health Monitoring: Methodologies and Applications

[...]

06 Nov 2016-Journal of Sensors
Ye Xiaowei, Chuan-Zhi Dong, Liu Tan
Structural Health Monitoring: with Piezoelectric Wafer Active Sensors

[...]

05 Dec 2007
Victor Giurgiutiu
Study of Sensor Network Applications in Building Construction

[...]

01 Jan 2013
Xiaotao Wang
Digital technologies in non-destructive testing

[...]

01 Oct 2019
A V Ponomarev, O V Ponomareva
Machine learning at the interface of structural health monitoring and non-destructive evaluation

[...]

16 Oct 2020-Philosophical Transactions of the Royal Society A
Paul Gardner, R. Fuentes, Nikolaos Dervilis, Carmelo Mineo, Stephen Pierce, Elizabeth J. Cross, Keith Worden 
Frequently Asked Questions (16)
Q1. What contributions have the authors mentioned in the paper "Real-time structural health monitoring for concrete beams: a cost-effective ‘industry 4.0’ solution using piezo sensors" ?

This research paper adopts the fundamental tenets of advanced technologies in industry 4. 0 to monitor the structural health of concrete beam members using cost effective non-destructive technologies. This research is testament to the fact that as technological advancements progress at an exponential rate, the cost of implementation continues to reduce to produce higher accuracy ‘ mass-market ’ solutions for industry practitioners. This study merges industry 4. 0 digital technologies with a novel low-cost and automated hybrid analysis for real-time structural health monitoring of concrete beams by fusing several multidisciplinary approaches in one integral technological configuration. 

However, this approach being a preliminary scoping study had several limitations and some significant lessons for future studies. The use of wired sensors and its complex and sensitive circuit could potentially lead to delays and damage to devices. Studies investigating the exact range and lifespan of piezoceramic sensors could also further assist in fine-tuning this technique for in ustrial use. 

As cement continually reacts with water and developstrong bonds between mix components to build the final concrete strength, a protectivelayer is necessary to protect the embedded sensors from its boundary, moisture damage,and corrosion (Sanches et al., 2019). 

Acting as a sensor, actuator, accelerator ortransducer within the concrete member, the piezoceramic sensors detect the electricalenergy converted from mechanical energy and convert it into a voltage output (Ballasand Schoen 2017). 

Acoustic techniques such as the rebound hammer, ultrasonic pulse velocity(UPV), impact echo, spectral wave analysis, crosshole sonic lagging or parallel seismichave various limitations. 

The testing frame is self-supported type andprovide a full circle of loading system, while the loading has been introduced through ahydraulic jack with load cell to monitor the actual applied load. 

The ultimate load at which the structures failed was recorded as 88.37 kN , 83.31 kN,78.71 kN and 89.61kN for test samples 1, 2, 3 and 4 respectively. 

Piezoceramic sensors have been utilised heavily for SHM in the aircraft industry (Chang2016; Shen et al., 2006), automobile (Martinotto et al., 2016) and manufacturing(Hossain et al., 2016) industries. 

In summary, although piezo elements have limitations of being fragile and non-waterresistant, their economic feasibility and simplicity of usage provide strong arguments forusing them on real-time SHM projects. 

it was anticipated that because the sensorswill collect data within a range of 20 – 50 mm, they were placed in the region ofexpected large damage on the beam. 

while it has been changed to deflection control of 1 mm/minute at the laterstages to ensure capturing the full load-deflection relationship and to avoid suddenfailure and damages to the instrumentations. 

This study investigates the application of low-costpiezoceramic sensors to detect deformations within the concrete structure (i.e., cracksand fractures) due to the member being placed under physical strain. 

The multidisciplinary approach (using Industry 4.0 advanced technologies) adoptedtowards solving an important maintenance issues associated with the constructionindustry has some significant theoretical and managerial implications. 

The four beams included 13sensors for each beam with five on the front and rear faces of the beam, one on the baseand two on the top (ref. Fig. 5 and 6). 

The main components used in the present ‘Industry 4.0’ study include: a Raspberry Pi;piezoceramic sensors; a breadboard; analogue to digital converter; and two 16-bitmultiplexers (refer to Figure 2).<Insert Figure 2 about here> 

conventional methods include different tests such as a simple human eyedetection of surface defects (Ghodoosi et al., 2018) or a compressive strength test whichonly provides results after a 28 day curing period (Yildirim et al., 2015).