Smart Sensing Using Electromagnetic Waves for Inspection of Defects in Rock Bolts

Yu, Jung-Doung; Lee, Jong Sub

doi:10.3390/s20102821

Cited by 13 publications

(8 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Overall, these values were similar, regardless of the probe length. Since the lengths of HETDR probes were higher than that of the conventional TDR probe, attenuation and dispersion may be more obvious in the case of the HETDR probe, causing a significant increase in the rising time [28]. Consequently, the travel time, dielectric constant, and SWC obtained through the HETDR probe were higher than those obtained through the conventional TDR probe.…”

Section: Hetdr Versus Conventional Tdrmentioning

confidence: 96%

“…Lee et al [27] reported that the TDR is an effective method for detecting necking defects in bored piles. Another application of the TDR method is the identification of defects in rock bolts used to improve the stability of tunnels and rock slopes [28]. Furthermore, Yu et al [29] suggested the use of a circular TDR system to enhance the resolution of scour depth monitoring around piers and bridge abutments.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Horizontally Elongated Time Domain Reflectometry System for Evaluation of Soil Moisture Distribution

Kim

Byun

2020

Sensors

Self Cite

View full text Add to dashboard Cite

The objective of this study was to develop a horizontally elongated time domain reflectometry (HETDR) system to evaluate the water content in nonuniformly wetted soils. The HETDR probe consists of three rods of stainless steel and a cuboid head: A center electrode and two outer electrodes are connected to the inner and outer conductors of a coaxial cable, respectively. An acrylic container divided into several segments was used to prepare nonuniformly wetted soils with different water contents for a series of model tests. The HETDR probe was placed horizontally at the middle height of each soil specimen, while a conventional time domain reflectometry (TDR) probe was applied vertically on the surface of the specimen. The experimental results show that as the soil water content (SWC) at a segment increases, the average amplitude decreases and the duration increases. The estimated SWC increases with the measured SWC, and especially, the difference between actual segment length and the segment length estimated from the HETDR probes is significant under dry conditions. This study demonstrates that HETDR may be a promising field-testing method for evaluating the average water content in nonuniformly wetted soils.

show abstract

Section: Hetdr Versus Conventional Tdrmentioning

confidence: 96%

Section: Introductionmentioning

confidence: 99%

Horizontally Elongated Time Domain Reflectometry System for Evaluation of Soil Moisture Distribution

Kim

Byun

2020

Sensors

Self Cite

View full text Add to dashboard Cite

show abstract

“…A non-destructive test method for monitoring rock bolt condition [186] is required and ultrasonic methods have previously been applied. While these sensors provide satisfactory performance, the ultrasonic energy from the bolt continues to pass into the nearby rock [187] and the ultrasonic sensors are costly, and specific skills are required for the data analysis [188]. Therefore, using piezoceramic transducers with electro-mechanical impendence sensors to monitor rock bolts is a new alternative [189].…”

Section: Rock Bolt Tension/stress Assessmentmentioning

confidence: 99%

MEMS technology and applications in geotechnical monitoring: a review

Barzegar

Blanks²,

Sainsbury

et al. 2022

Meas. Sci. Technol.

View full text Add to dashboard Cite

In-situ monitoring is an important aspect of geotechnical projects to ensure safety and optimise design measures. However, existing conventional monitoring instruments are limited in their accuracy, durability, complex and high cost of installation and requirement for ongoing real time measurement. Advancements in sensing technology in recent years have created a unique prospect for geotechnical monitoring to overcome some of those limitations. For this reason, micro-electro-mechanical system (MEMS) technology has gained popularity for geotechnical monitoring. MEMS devices combine both mechanical and electrical components to convert environment system stimuli to electrical signals. MEMS-based sensors provide advantages to traditional sensors in that they are millimetre to micron sized and sufficiently inexpensive to be ubiquitously distributed within an environment or structure. This ensures that the monitoring of the in-situ system goes beyond discrete point data but provides an accurate assessment of the entire structures response. The capability to operate with wireless technology makes MEMS microsensors even more desirable in geotechnical monitoring where dynamic changes in heterogeneous materials at great depth and over large areas are expected. Many of these locations are remote or hazardous to access directly and are thus a target for MEMS development. This paper provides a review of current applications of existing MEMS technology to the field/s of geotechnical engineering and provides a path forward for the expansion of this research and commercialisation of products.

show abstract

“…A general procedure for the installation of rock bolts includes drilling, the insertion of rock bolts, and grouting. Drill hole wall collapse, groundwater flow, poor grout mixture, and leakage of grout into the surrounding voids are some of the factors responsible for affecting the quality of grouting used in rock bolting operations [2]. There are various types of rock bolts that are available to us.…”

Section: Introductionmentioning

confidence: 99%

Review of Non-Destructive Methods for Rock Bolts Condition Evaluation

Lama

Momayez

2023

Mining

View full text Add to dashboard Cite

Rock bolts are one of the most effective and conventional support techniques widely used in underground mining and tunneling operations to stabilize excavations and jointed rock masses. External factors such as corrosion, overloading, and improper installation can weaken rock bolts, which could result in ground failure causing injury or loss of life and production. Monitoring the health condition of rock bolts will reduce the risk of accidents providing a safer environment for workers and equipment. This paper reviews monitoring methods currently used to assess the condition of installed rock bolts. Furthermore, we classify the surveyed techniques depending on the type of problems they attempt to solve. Presented are methods such as ultrasonics, fiber optics, piezoelectric, electromagnetics, impact echo, acoustic emission, and numerical algorithms. Each method is based on a unique physical principle that aids in evaluating corrosion and strain levels in the rock bolt. However, recent research to detect corrosion has primarily focused on rebar type of rock bolts used in concrete structures. Consequently, more research is needed to monitor the condition of the other types of rock bolts used in the industry such as cable bolts and split set bolts. In conclusion, the paper highlights various methods of studying rock bolt failure initiated by strain, corrosion, and improper installation of the grouts. It also explores the research advancement made for the study of rock bolt failure. This investigation is specifically beneficial to the mining and tunneling industry for better understanding and prediction of rock bolt failure.

show abstract

Smart Sensing Using Electromagnetic Waves for Inspection of Defects in Rock Bolts

Cited by 13 publications

References 32 publications

Horizontally Elongated Time Domain Reflectometry System for Evaluation of Soil Moisture Distribution

Horizontally Elongated Time Domain Reflectometry System for Evaluation of Soil Moisture Distribution

MEMS technology and applications in geotechnical monitoring: a review

Review of Non-Destructive Methods for Rock Bolts Condition Evaluation

Contact Info

Product

Resources

About