Abstract

Floating covers are examples of a large membrane structure used at sewage treatment plants. At the Western Treatment Plant (WTP), Werribee, Melbourne, Australia, floating covers are used in the anaerobic lagoons. They are deployed to assist with the anaerobic treatment of the raw sewage beneath, to harness the methane-rich biogas generated, and for odor control. In this respect, these floating covers are important assets for harnessing a sustainable and renewable energy source, as well as protecting the environment from the release of the damaging greenhouse methane-rich biogas from the treatment plant. Given the continuous nature of the biological process beneath the cover, the forces imposed on the floating cover will change with time. Hence, the monitoring and the assessment of the structural integrity of the floating cover are of paramount importance. These floating covers are made from high-density polyethylene (HDPE), a polymeric material. The size of these covers, the hazardous environment, and the expected life span demand a novel, remotely piloted, unmanned aerial vehicle based noncontact technique for the structural health assessment. This assessment methodology will utilize photogrammetry as the basis for determining the surface deformation of the membrane. This paper reports on an experimental study to determine the flight parameters and to assess the accuracy of the measurement technique. It was conducted over an area having similar dimensions to the large covers at the WTP. There are also features in this area, which are of similar scale to those expected in the floating cover. A total of nine test flights were used to investigate the parameters for optimal definition of the significant features to describe the deformation of the floating cover. The findings inform the selection of the unmanned aerial vehicle assisted photogrammetry parameters for optimal flight altitude, photogrammetry image overlap, and flight grid path for future integrity assessment of the floating covers. Two trial flights at WTP are also discussed to demonstrate the effectiveness of this noncontact technique for the future structural health assessment and in assisting with the operation of this large high-value asset.

References

References
1.
Su
,
Z.
,
Yuan
,
S.
, and
Sohn
,
H.
,
2018
,
Proceedings of the 7th Asia Pacific Workshop on Structural Health Monitoring (APWSHM-2018)
,
NDT.net
,
Bad Breisig, Germany
.
2.
Breitenbach
,
A.
, and
Smith
,
M.
,
2006
, “
Overview of Geomembrane History in the Mining Industry
,”
The Proceedings of the 8th Bi-Annual Meeting of the International Geosynthetics Society
,
Japan
,
Sept. 18–22
, p.
044
.
3.
Rowe
,
R. K.
, and
Sangam
,
H. P.
,
2002
, “
Durability of HDPE Geomembranes
,”
Geotext. Geomembr.
,
20
(
2
), pp.
77
95
. 10.1016/S0266-1144(02)00005-5
4.
Scheirs
,
J.
,
2009
,
A Guide to Polymeric Geomembranes: A Practical Approach
,
John Wiley & Sons
,
New York
.
5.
Eisenbeiss
,
H.
, and
Sauerbier
,
M.
,
2011
, “
Investigation of UAV Systems and Flight Modes for Photogrammetric Applications: Investigation of UAV Systems and Flight Modes
,”
Photogramm. Rec.
,
26
(
136
), pp.
400
421
. 10.1111/j.1477-9730.2011.00657.x
6.
Dominici
,
D.
,
Alicandro
,
M.
, and
Massimi
,
V.
,
2016
, “
UAV Photogrammetry in the Post-Earthquake Scenario: Case Studies in L’Aquila
,”
Geomat. Nat. Haz. Risk
,
8
(
1
), pp.
87
103
. 10.1080/19475705.2016.1176605
7.
Tucci
,
G.
,
Parisi
,
E. I.
,
Castelli
,
G.
,
Errico
,
A.
,
Corongiu
,
M.
,
Sona
,
G.
,
Viviani
,
E.
,
Bresci
,
E.
, and
Preti
,
F.
,
2019
, “
Multi-Sensor UAV Application for Thermal Analysis on a Dry-Stone Terraced Vineyard in Rural Tuscany Landscape
,”
Int. J. Geo-Inf.
,
8
(
2
), p.
87
. 10.3390/ijgi8020087
8.
Chiabrando
,
F.
,
Lingua
,
A.
, and
Piras
,
M.
,
2013
, “
Direct Photogrammetry Using UAV: Tests and First Results
,”
ISPRS Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci.
,
XL-1/W2
, pp.
81
86
. 10.5194/isprsarchives-XL-1-W2-81-2013
9.
Baqersad
,
J.
,
2015
, “
A Non-Contacting Approach for Full Field Dynamic Strain Monitoring of Rotating Structures Using the Photogrammetry, Finite Element, and Modal Expansion Techniques
,”
University of Massachusetts Lowell
,
Lowell, MA
.
10.
Baqersad
,
J.
,
Niezrecki
,
C.
, and
Avitabile
,
P.
,
2015
, “
Full-Field Dynamic Strain Prediction on a Wind Turbine Using Displacements of Optical Targets Measured by Stereophotogrammetry
,”
Mech. Syst. Sig. Process.
,
62–63
, pp.
284
295
. 10.1016/j.ymssp.2015.03.021
11.
Baqersad
,
J.
,
Poozesh
,
P.
,
Niezrecki
,
C.
, and
Avitabile
,
P.
,
2017
, “
Photogrammetry and Optical Methods in Structural Dynamics—A Review
,”
Mech. Syst. Sig. Process.
,
86
Part B, pp.
17
34
. 10.1016/j.ymssp.2016.02.011
12.
Baqersad
,
J.
,
Poozesh
,
P.
,
Niezrecki
,
C.
, and
Avitabile
,
P.
,
2016
, “
A Non-Contacting Approach for Full-Field Strain Monitoring of Rotating Structures
,”
ASME J. Vib. Acoust.
,
138
(
3
), p.
031008
. 10.1115/1.4032721
13.
Pappa
,
R. S.
,
Black
,
J. T.
,
Blandino
,
J. R.
,
Jones
,
T. W.
,
Danehy
,
P. M.
, and
Dorrington
,
A. A.
,
2003
, “
Dot-Projection Photogrammetry and Videogrammetry of Gossamer Space Structures
,”
J. Spacecr. Rockets
,
40
(
6
), pp.
858
867
. 10.2514/2.7047
14.
Zhao
,
B.
,
Chen
,
W.
,
Hu
,
J.
,
Chen
,
J.
,
Qiu
,
Z.
,
Zhou
,
J.
, and
Gao
,
C.
,
2015
, “
An Innovative Methodology for Measurement of Stress Distribution of Inflatable Membrane Structures
,”
Meas. Sci. Technol.
,
27
(
2
), p.
025002
. 10.1088/0957-0233/27/2/025002
15.
Chiu
,
W. K.
,
Ong
,
W. H.
,
Kuen
,
T.
, and
Courtney
,
F.
,
2017
, “
Large Structures Monitoring Using Unmanned Aerial Vehicles
,”
Procedia Eng.
,
188
, pp.
415
423
. 10.1016/j.proeng.2017.04.503
16.
Ong
,
W. H.
,
Chiu
,
W. K.
,
Kuen
,
T.
, and
Kodikara
,
J.
,
2017
, “
Determination of the State of Strain of Large Floating Covers Using Unmanned Aerial Vehicle (UAV) Aided Photogrammetry
,”
Sensors
,
17
(
8
), p.
1731
. 10.3390/s17081731
17.
Barazzetti
,
L.
,
Forlani
,
G.
,
Remondino
,
F.
,
Roncella
,
R.
, and
Scaioni
,
M.
,
2011
, “
Experiences and Achievements in Automated Image Sequence Orientation for Close-Range Photogrammetric Projects
,”
Proceedings SPIE 8085, Videometrics, Range Imaging and Applications XI, 80850F
,
Munich, Germany
,
May 23–26
, pp.
1
13
.
18.
Westoby
,
M. J.
,
Brasington
,
J.
,
Glasser
,
N. F.
,
Hambrey
,
M. J.
, and
Reynolds
,
J. M.
,
2012
, “
Structure-From-Motion Photogrammetry: A Low-Cost, Effective Tool for Geoscience Applications
,”
Geomorphology
,
179
, pp.
300
314
. 10.1016/j.geomorph.2012.08.021
19.
Triggs
,
B.
,
Zisserman
,
A.
, and
Szeliski
,
R.
,
2000
, “
Bundle Adjustment. A Modern Synthesis, Vision Algorithms: Theory and Practice
,”
Proceedings of International Workshop on Vision Algorithms
,
September 1999
,
Springer-Verlag
,
New York
.
20.
DJI
,
2018
,
Matrice 600 PRO User Manual V1.0
,
DJI
,
Shenzhen, China
.
21.
DJI
,
2017
,
Phantom 4 PRO/PRO+ User Manual V1.4
,
DJI
,
Shenzhen, China
, pp.
62
64
.
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