Method for Identifying the Grout Defects of the Anchors at Ultra-Early-Stage Based on Time-Domain Waveform Characteristic Reflection Points

Sun, Bing; Zhu, Cong; Zou, Junhui; Wang, Shanyong; Zeng, Sheng

doi:10.1134/s106183092360079x

Cited by 3 publications

(2 citation statements)

References 36 publications

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“…The wave velocities obtained at different filtering levels are presented in table 3. It can be observed that the wave velocities obtained from d4 and d5 exhibit significant differences when compared to the results calculated in existing literature [31][32][33]. In the case of d6, although the size of the wave velocity is consistent with the range of the existing literature, the size changes under the influence of the size effect are quite different [34][35][36].…”

Section: Methodssupporting

confidence: 61%

“…However, the wave velocity obtained by the FDM method differs significantly from the literature [30], suggesting that IIR and IIR-FDM perform better than FDM in extracting characteristic parameters. Furthermore, following the calculation method outlined in [33], the theoretical wave velocity of A-1 is calculated as 3849.40 m s −1 . Among the three methods, the IIR-FDM processing yields the smallest wave velocity error, only 1.35%.…”

Section: Methodsmentioning

confidence: 99%

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Investigation on the dynamic characteristics of anchor rods considering size effect and pull-out loads based on IIR-FDM

Sun,

Zhu,

Song

et al. 2024

Meas. Sci. Technol.

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When the surrounding rock of tunnel anchor bars has boundaries, the signals obtained from NDT of anchor rods will be simultaneously affected by size effects and pull-out loads, leading to potential misinterpretation of the test results. In order to accurately assess the anchorage quality of anchor rods under this interference, NDT and numerical simulations of anchor rods subjected to different anchorage quality were conducted under the influence of size effects and pull-out loads. A signal filtering method, which combines the infinite impulse response-finite difference method , was proposed for identify the impact of size effects. The study analyzed the variations in wave velocity and fundamental frequency of anchor rods with anchorage defects and intact anchor rods under the influence of size effects and pull-out loads. The results indicate that the IIR-FDM method, in comparison to the traditional wavelet method, provides better agreement between the calculated wave velocities and existing findings. With the increase of size effect, the wave velocity and amplitude ratio of the anchor rods decrease, and the fundamental frequency increases first and then decreases. As the working load on the anchor rods increases, the wave velocity initially decreases, then rises, while the fundamental frequency initially increases and then experiences a slight decrease. The presence of anchorage defect results in an increase in the wave velocity and amplitude ratio of the anchor rods, while causing a decrease in the fundamental frequency. This effect of defects on wave velocity and fundamental frequency is more pronounced at lower loads. The wave velocity after IIR-FDM processing has a small error with the simulated wave velocity, indicating the reliability of the processing method.

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Section: Methodssupporting

confidence: 61%

Section: Methodsmentioning

confidence: 99%

Investigation on the dynamic characteristics of anchor rods considering size effect and pull-out loads based on IIR-FDM

Sun,

Zhu,

Song

et al. 2024

Meas. Sci. Technol.

Self Cite

View full text Add to dashboard Cite

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Variation characteristics of key dynamic measurement signals of anchor bolts with different anchorage qualities under pull-out loads

Sun,

Zhu,

Zou

et al. 2024

Alexandria Engineering Journal

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Investigation on the variations of dynamic characteristics of anchor bolts considering transverse inertia effects under tensile loads

Sun,

Zou,

Peng

et al. 2024

Meas. Sci. Technol.

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In the case where tunnel anchor bolts are located in strata with limited surrounding rock boundaries, the response signals of the anchor bolts are affected by the tensile load and the transverse inertia effect, resulting in a decrease in the reliability of the non-destructive testing (NDT) results. To accurately assess the anchorage quality under these disturbances, a vibration energy loss model for anchor bolts after excitation was proposed. NDT experiments and numerical simulation studies were conducted on intact and defective anchor bolts under different conditions, analyzing the variation patterns of structural dynamic characteristics such as the the first-order natural frequency, the first-order damping ratio, and the vibration energy loss under the influence of tensile load and transverse inertia effect. The results show that during the gradual increase of the tensile load, the first-order natural frequency and the first-order damping ratio exhibit an overall trend of first increasing and then decreasing, while the rate of the energy loss initially decreases and then increases. The presence of anchorage defects leads to a reduction in the first-order natural frequency, the first-order damping ratio, and the energy loss of the anchor bolt. As the transverse inertia effect intensifies, the first-order natural frequency initially increases and then decreases, the first-order damping ratio decreases, and the energy loss initially decreases slightly before increasing. The numerical simulation verifies the applicability of the theoretical model and explores the influence of defect location on energy loss. The results indicate that the closer the defect location is to the free end, the less the vibration energy loss of the anchor bolt.

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Method for Identifying the Grout Defects of the Anchors at Ultra-Early-Stage Based on Time-Domain Waveform Characteristic Reflection Points

Cited by 3 publications

References 36 publications

Investigation on the dynamic characteristics of anchor rods considering size effect and pull-out loads based on IIR-FDM

Investigation on the dynamic characteristics of anchor rods considering size effect and pull-out loads based on IIR-FDM

Variation characteristics of key dynamic measurement signals of anchor bolts with different anchorage qualities under pull-out loads

Investigation on the variations of dynamic characteristics of anchor bolts considering transverse inertia effects under tensile loads

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