Application of Digital Image Correlation Technology in Geotechnical
Structure Measurement
ZhenZhu Guo
*
, Lu Wang and Xiaojuan Shi
Tianjin College, University of Science and Technology Beijing, Tianjin, China
Keywords: Digital Images, Civil Structures, Bridge Engineering, Applicability.
Abstract: With the international trend towards digitization and intelligence, traditional geotechnical testing technology
has gradually been replaced by digital image technology. This article focuses on the basic principle of digital
image correlation method, discusses the applicability of this technology in strain measurement of geotechnical
structures in civil engineering and bridge engineering, and discusses the development prospects of this
technology.
1 INTRODUCTION
As an important part of civil engineering
construction, the accuracy of geotechnical
measurement results determines the overall quality of
the project. However, existing testing techniques
often require manual analysis and processing of data,
resulting in low efficiency; The high cost of
machinery and labor used is not conducive to the
formation of scale. With the current international
trend, the production system of digital maps and the
intelligence and digitization of basic urban
information are continuously promoted. At the same
time, surveyors transmit the collected data in real-
time to the network, achieving visual manipulation
and efficient, convenient, and accurate data
transmission. The new demand for measurement
technology has accelerated the replacement of
traditional manual drawing and mechanical
measurement, and the application of digital image
correlation technology in geotechnical structure
measurement has emerged (Cao Lu, 2018).
Digital image related technology was proposed
by scholars in the United States and Japan as early as
the 1980s and has been invested in research and
development. It is a modern optical measurement
technology that integrates full field, three-
dimensional, and non-contact measurements. Due to
its strong adaptability to the external environment,
low susceptibility to light interference, high degree of
mechanical automation, and good operability, it has
been widely applied in various fields such as
bioscience, mechanical simulation, civil engineering,
food safety, etc. In the field of civil engineering
measurement, digital image related technology can be
applied to measure the static displacement of objects
during loading, such as torsion, bending, and tensile
deformation. The accuracy of the results has been
verified by scholars using finite element methods.
2 BASIC PRINCIPLES
Digital image correlation technology, also known as
digital speckle correlation method, mainly consists of
CCD or COMS cameras, lighting sources, image
acquisition cards, and computers (Zhang Shunqing,
2017). It uses a CCD or COMS camera to store the
captured image of the specimen on an image
acquisition card, divides it into regions of interest at the
pixel level through computer processing, and defines
the specimen in each sub region of the region of
interest as a rigid body. A search algorithm is used to
calculate according to the pre-set correlation function,
and the deformed rigid body specimen is compared
with the region of interest to find the region with the
highest correlation coefficient value, and locate the
deformed rigid body specimen, and then calculate the
deformation position of the rigid body specimen.
Figure 1. Schematic diagram of digital image related
technology measurement system.
Guo, Z., Wang, L. and Shi, X.
Application of Digital Image Correlation Technology in Geotechnical Structure Measurement.
DOI: 10.5220/0012284100003807
Paper published under CC license (CC BY-NC-ND 4.0)
In Proceedings of the 2nd International Seminar on Artificial Intelligence, Networking and Information Technology (ANIT 2023), pages 367-369
ISBN: 978-989-758-677-4
Proceedings Copyright © 2024 by SCITEPRESS Science and Technology Publications, Lda.
367
2.1 Application of Digital Image
Correlation Method in Bridge
Crack Deformation Monitoring
Monitoring
In bridge engineering, due to long-term external loads
such as vehicle loads on the beam structure, cracks
can easily occur over time, which can lead to
insufficient bearing capacity of the bridge structure.
Therefore, timely detection of cracks on the bridge
structure can help workers prevent accidents and
reduce the occurrence of dangerous accidents.
According to the specifications of ACI and CBE, the
allowable width of transverse cracks in bridge
structures is 0.2mm, which is more stringent in areas
with corrosion hazards. The allowable width defined
as transverse cracks is 0.1mm; At the same time,
longitudinal cracks are not allowed to appear in the
beam structure of the bridge. For cracks and other
deformations on the bridge beam structure, the
electrical measurement method is usually used, which
selects points for the bridge beam structure and
measures the strain at representative points. However,
this method is difficult to measure the strain at the mid
span of the bridge, and when measuring deformations
with minimal deformation, using a magnifying glass
cannot meet the accuracy requirements. Therefore,
non-contact digital image correlation technology was
used in the measurement of cracks in bridge beam
materials. In operational engineering, the field of
view of the digital camera was adjusted to 102.64. *
82.09, and the calibration result was 0.0802 pixel at
the pixel level. By intercepting the deformation area
of 30 * 30 pixel in DIC software and comparing the
displacement difference between the two areas, it was
found that digital correlation technology has
superiority and feasibility in measuring the
deformation properties of bridge beam structures
under dynamic and static loads (Bai Xiaohong, 2011).
Figure 2. Measurement process of strain points in bridge
structures (Wang Jing, 2003).
2.2 Application of Digital Image
Correlation Method in Rock
Microscopic Material Monitoring
In civil engineering, whether natural geotechnical
materials or artificial materials, there is heterogeneity
within them. This non-uniformity will lead to uneven
strain in the structure under external loads, resulting
in cracks in geotechnical structures constructed from
geotechnical or synthetic materials (airport taxiways,
large embankment supports, highway pavements),
leading to a decrease in their mechanical
performance. However, the detection of the
aforementioned geotechnical structures faces
challenges such as large monitoring areas and limited
selection of detection methods. Usually, traditional
sensors cannot solve problems such as cracks on
highways, and laser, radar, ultrasound, and other
technologies are used to solve them. However, if non-
contact detection of the object being tested is
required, digital image processing technology will
emerge. It uses DIP technology to analyze the image
situation and further detect the bedding structure of
concrete materials in geotechnical structures, Further
research will be conducted on the mechanical and
physical properties of rock and soil materials such as
concrete.
2.3 Application of Digital Image
Correlation Method in Weld
Strength of Materials Performance
Detection
Similar to rock materials, weld material is also a non-
uniform material, which is affected by different
materials, temperatures, and construction processes,
resulting in different mechanical properties;
Therefore, it is very important to conduct quantitative
research on weld material in different regions. With
the growing use of DIC, many scholars have applied
digital image correlation technology to the weld
research of base metal. They take TC4 titanium alloy
as the research object, place it in the uniaxial Tensile
testing, and measure the strain field of weld material
under different loads and areas. According to digital
image correlation technology, the experimental
results show that the strain in the base metal area is
much greater than that in the weld seam area and the
affected area, and the base metal area has good
toughness. At the same time, the finite element model
is used to verify the above results, indicating that
using digital correlation technology can effectively
detect the mechanical properties of the weld seam
ANIT 2023 - The International Seminar on Artificial Intelligence, Networking and Information Technology
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material, with high accuracy and good measurement
reliability (Hang Chao, 2013).
2.4 Applied to Damage Observation
and Fatigue Assessment of Steel
Components
Steel structural materials have the advantages of light
weight, short construction period, strong seismic
performance, and easy transportation, and are
currently highly praised by domestic and foreign
countries. With the vigorous promotion of steel
structures and prefabricated installation methods,
more and more building forms are constructed using
steel structures, such as steel residential buildings,
steel bridges, etc. It can be seen that the usage of steel
structures is increasing day by day. Therefore, the
damage and fatigue assessment of steel structural
components will play a very important role in the
operation of steel structural components, and have
very good development prospects. Traditionally, the
methods for damage and fatigue testing of steel
structural components have low efficiency, are prone
to blind spots in the detection process, and
measurement instruments are relatively expensive.
With the continuous fermentation of image
recognition technology, operations based on digital
image related technologies have emerged. Before the
experimental operation, the specimens need to be
divided into base metal and weld metal specimens. A
fatigue testing machine is used to cyclically load the
specimens, with a minimum loading setting of 10kN.
Optical calibration equipment is used to calibrate the
loaded specimens to form speckle. The fatigue
performance of the base metal or weld material of the
steel structure specimen is determined by comparing
the three-dimensional displacement parameters and
three-dimensional strain parameters of the speckle.
The experimental results indicate that this method has
a certain degree of predictability and can help
technicians detect fatigue signals of steel structural
materials in advance, providing effective support for
the study of residual bearing capacity of steel
structural components (Yang Yuntao, 2022).
3 CONCLUSION AND OUTLOOK
Digital image related technology is a widely used
technology with good development prospects and
advantages. It has good measurement stability in civil
engineering materials and bridge engineering, and its
future development trend will continue to develop
towards intelligence, wide applicability, high
precision, high efficiency, Technological
convergence and other aspects, bringing more
benefits to mass industrial production and life; At the
same time, there are still urgent problems to be solved
in digital image related technologies, including
further overcoming challenges in low-quality image
processing, multimodal image processing, privacy
protection, and other aspects.
Of course, in addition to the above, there are also
many material measurements using DIC technology,
such as internal deformation of pipelines (Xiangjun
Dai, 2023) and fatigue cracks. As well as rock cracks
under high water pressure (Yun Tian, 2023), it can be
seen that digital correlation technology (DIC) has
applicability in various fields of engineering and is
still worth further exploration.
REFERENCES
Cao Lu. The Application Significance of Digital Image
Technology in Building Materials Testing (J). Art
Technology, 2018, 31 (10): 287-288
Zhang Shunqing, Gao Chenjia, Zhang Long. Development
and Latest Applications of Digital Image Correlation
Technology in Stress and Strain Measurement (J).
Imaging Science and Photochemistry, 2017, 35 (02):
193-198
Bai Xiaohong. Application of Digital Image Correlation
(DIC) measurement method in material deformation
research (D). Northeastern University, 2011
Wang Jing, Li Hongqi, Xing Dongmei, etc. Application of
digital image correlation method in Deformation
monitoring of bridge cracks (J). Mechanics Quarterly,
2003 (04): 512-516
Hang Chao, Yang Guang, Li Yulong, etc. The application of
digital image correlation method in the measurement of
mechanical properties of weld Strength of materials (J).
Journal of Aeronautics, 2013, 34 (10): 2372-2382
Yang Yuntao Research on damage observation and fatigue
assessment of steel members based on digital image
correlation technology (D). Beijing Jiaotong University,
2022. DOI: 10.26944/d.cnki. gbfju. 2022.003469
Xiangjun Dai, Jiankang Qi, Mengqiao Xu,
et,Omnidirectional 3D-DIC method for determining
inner deformation in pipelines, Measurement, Volume
216,2023,112924,ISSN 0263-2241,
https://doi.org/10.1016/j.measurement.2023.112924.
Yun Tian, Xiyao Zhao, Yating Tai, et, Crack extension at
the concrete-rock interface damaged by high-pressure
water environment: DIC research (J), Theoretical and
Applied Fracture Mechanics, 2023, 103966, ISSN
0167-8442,
https://doi.org/10.1016/j.tafmec.2023.103966.
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