Specific variability of features of recorded signals in georadar detection of voids at rock–lining interface

Spotlight is on detection of voids at the rock–lining interface in metro tunnels by features identified in processing of georadar profiles. The georadar and seismic surveys in the Moscow metro tunnels revealed high variance in the ability of features to point at an anomaly, and disclosed numerous cases of false triggering. The variability arose in transition between test subjects but was weak within the limits of the same subject. For this reason, it is proposed to set a void detection system with respect to some references (confirmed using other methods) and to use this system further for the whole test subject. The number of the false triggering and missed target events is suggested to minimize by using sets of features. Such system may operate in an advisory mode to reduce interpreter’s errors when processing bulks of data. A series of estimates is proposed to select features to be integrated in a check set. The article offers estimation of intensity of an anomaly distinguished by selected features; reliability of distinguishing between the void and no void situations using parameters of ROC-curves; independence of features using linear correlation factors. Behavior of the features is analyzed using in-situ data. It is found that the moduli of correlation factors of the features in the radarogram areas with and without a void, |RР| and |RN|, respectively, form well-splitting clusters, which enables decision-making on independence of the features. Parameters of the clusters are stable between the test subjects, and, therefore, it is possible to use the discriminant curve equation to integrate features in a set.

Nabatov V. V., Utkina A. V. Specific variability of features of recorded signals in georadar detection of voids at rock–lining interface. MIAB. Mining Inf. Anal. Bull. 2023;(7):52–63. [In Russ]. DOI: 10.25018/0236_1493_2023_7_0_52.

V.V. Nabatov¹, Cand. Sci. (Eng.), Assistant Professor, e-mail: nv4@mail.ru, ORCID ID: 0000-0002-0047-0462,
A.V. Utkina¹, Graduate Student,
¹ National University of Science and Technology «MISiS», 119049, Moscow, Russia.

V.V. Nabatov, e-mail: nv4@mail.ru.

1. Jia-Xuan Zhang, Ning Zhang, Annan Zhou, Shui-Long Shen Numerical evaluation of segmental tunnel lining with voids in outside backfill. Underground Space. 2022, vol. 7, no. 5, pp. 786—797. DOI: 10.1016/j.undsp.2021.12.007.

2. Chengping Zhang, Bo Min, Haili Wang, Sulei Zhang Mechanical properties of the tunnel structures with cracks around voids behind linings. Thin-Walled Structures. 2022, vol. 181, article 110117. DOI: 10.1016/j.tws.2022.110117.

3. Dingli Zhang, Tong Xu, Huangcheng Fang, Qian Fang, Liqiang Cao, Ming Wen Analytical modeling of complex contact behavior between rock mass and lining structure. Journal of Rock Mechanics and Geotechnical Engineering. 2022, vol. 14, no. 3, pp. 813—824. DOI: 10.1016/j.jrmge.2021.10.007.

4. Zijian Ye, Yuyou Yang, Ying Ye Three-dimensional effects of multiple voids behind lining on the mechanical behavior of tunnel structure. Ain Shams Engineering Journal. 2023, vol. 14, no. 4, article 101949. 10.1016/j.asej.2022.101949.

5. Hai-Xiang TangShi-Guo Long, Ting Li Quantitative evaluation of tunnel lining voids by acoustic spectrum analysis. Construction and Building Materials. 2019, vol. 228, article 116762. DOI: 10.1016/j.conbuildmat.2019.116762.

6. Voznesenskii A. S., Nabatov V. V. Identification of filler type in cavities behind tunnel linings during a subway tunnel surveys using the impulse-response method. Tunnelling and Underground Space Technology. 2017, vol. 70, pp. 254—261. DOI: 10.1016/j.tust.2017.07.010.

7. Fei Yao, Chen Guangyu Time-frequency analysis of impact echo signals of grouting defects in tunnels. Russian Journal of Nondestructive Testing. 2019, vol. 55, no. 8, pp. 581—595. DOI: 10.1134/S1061830919080102.

8. Andrianov S. V. GPR monitoring of space between lining and rock in underground mines. MIAB. Mining Inf. Anal. Bull. 2019, no. 5, pp. 124—132. [In Russ]. DOI: 10.25018/0236-14932019-05-0-124-132.

9. Baryshnikov V. D., Khmelinin A. P., Denisova E. V. GPR detection of inhomogeneities in concrete lining of underground tunnels. Fiziko-tekhnicheskie problemy razrabotki poleznykh iskopaemykh. 2014, no. 1, pp. 30—38. [In Russ].

10. Fei Xu, He Li, Hongge Yao, MingShou An Detection method of tunnel lining voids based on guided anchoring mechanism. Computers & Electrical Engineering. 2021, vol. 95, article 107462. DOI: 10.1016/j.compeleceng.2021.107462.

11. Sokolov K. O. Frequency-time presentation of georadar profiles based on continuous wavelet transform. Fiziko-tekhnicheskie problemy razrabotki poleznykh iskopaemykh. 2014, no. 2, pp. 77—81. [In Russ].

12. Shkuratnik V. L., Nikolenko P. V. Spectral characteristics of acoustic emission in carbon fiber-reinforced composite materials subjected to cyclic loading. Advances in Materials Science and Engineering. 2018, vol. 2018, article 1962679. DOI: 10.1155/2018/1962679.

13. Fedorova L. L., Soloviev E. E., Sokolov K. O., Kulyandin G. A. GPR research of geocryological objects in rock mass in permafrost zone. Gornyi Zhurnal. 2019, no. 2, pp. 38—42. [In Russ]. DOI: 10.17580/gzh.2019.02.07.

14. Nikitin A. A., Khmelevskoy A. A. Kompleksirovanie geofizicheskikh metodov [Geophysical methods complexation], Tver, OOO «Izdatel'stvo GERS», 2004, 294 p.

15. Kapustin V. V., Churkin A. A., Shirobokov M. P. Experience of ground penetrating radar application for foundation slabs quality control. Geotekhnika. 2021, vol. 13, no. 1, pp. 68—79. [In Russ]. DOI: 10.25296/2221-5514-2021-13-1-68-79.

16. Kapustin V. V., Sinitsin A. V. The application of attribute analysis for the solution of applied problems of GPR profiling. Geofizika. 2018, no. 2, pp. 17—23. [In Russ].

17. Pudova N. G., Kapustin V. V., Kuvaldin A. V. Primenenie atributnogo analiza dlya interpretatsii georadiolokatsionnykh dannykh [Application of attribute analysis for GPR data interpretation], available at: https://geoinfo.ru/product/pudova-natalya-gennadevna/primenenieatributnogo-analiza-dlya-interpretacii-georadiolokacionnyh-dannyh-36819.shtml (accessed 16.01.2022).

18. Nabatov V. V., Utkina A. V. Behavior of the quality factor and its constituents in radar detection of voids at the rock–lining interface. MIAB. Mining Inf. Anal. Bull. 2022, no. 6, pp. 142—155. [In Russ]. DOI: 10.25018/0236_1493_2022_6_0_142.

19. Nabatov V. V., Gaisin R. M., Voznesensky A. S. Geo radar data-based assessment of ground–and-lining contact surface quality in underground railway tunnels. MIAB. Mining Inf. Anal. Bull. 2013, no. 9, pp. 157—163. [In Russ]. DOI: 10.25018/0236_1493_2022_6_0_142.

20. Nabatov V. V., Voznesenskiy A. S. Georadar detection of voids at the soil-lining inter-face in subway tunnels. Gornyi Zhurnal. 2015, no. 2, pp. 15—20. [In Russ].