IN-SITU WALL CONCRETE QUALITY USING VELOCITY FIELD-DEPENDENT MIGRATION IN ZIGANA AND TORUL TUNNELS

In the scope of this study, the old Zigana and newly-built Torul Tunnels on an important transportation route were selected as the study areas. As the main purpose, monitoring of the distortions in the sidewall concrete lining of the Zigana and Torul tunnels were evaluated by using Diffraction 2D-velocity and Kirchhoff 2D-velocity migrations. Firstly, an artificial radargram was created based on the Finite Difference Time Domain method by taking the model of a tunnel wall structure. Then, for the results obtained from the model, a single velocity value was defined and the migration results were compared. However, as known to all, the outcome of migration by defining a single velocity value from radargrams with too many reflections do not give accurate results. Therefore, the Diffraction 2D-velocity and Kirchhoff 2D-velocity migrations were applied to these radargrams based on the velocity fields and their results were compared. Thus, we suggested that Diffraction 2D-velocity migration gives better results than those of the other in terms of focusing and resolution. When the amplitude slice maps obtained after applying Diffraction 2D-velocity were evaluated, it was observed that deteriorations in the structure continued up to a depth of 75 cm. However, the other type of migration is not very successful to move the distortions to their correct positions after a depth of 37 cm. Thus, in order to apply the migration results correctly, it is recommended to use velocity field.

Keywords:

GPR, Zigana and Torul tunnels, 2D velocity field two migrations types, amplitude-slice maps,

PDF

___

[1] Pajewski L., Fontul S., and Solla M. (2019) Ground-penetrating radar for the evaluation and monitoring of transport infrastructures. Chapter 10, Innovation in Near-Surface Geophysics, Elsevier.
[2] Lehmann F. (2015) Practical application of non-destructive test methods at a single-shell tunnel lining, in: Proc. of the 7th fib PhD Symposium in Stuttgart, Germany Sept. 11-13.
[3] Salvi R., Ramdasi A., Kolekar Y., and Bhandarkar L.V. (2019) Use of Ground-Penetrating Radar (GPR) as an Effective Tool in Assessing Pavements—A Review. Geotechnics for Transportation Infrastructure pp 85-95.
[4] Moropoulou A., Lampropoulos K. C., Sotiropoulos P., and Papageorgiou C. (2019) The Plaka Bridge in Epirus: Ground Penetrating Radar Prospection of Surviving Parts of the Collapsed Bridge, to Provide Structural Information for Its Reconstruction, Nondestructive Evaluation and Monitoring Technologies, Documentation, Diagnosis and Preservation of Cultural Heritage pp 91-106.
[5] Sarı M., and Öztürk S. (2018) Detection of the complex ground problems by ground penetrating radar: Examples from Gümüşhane University, Sigma J Eng & Nat Sci. 36 (4), 1295-1308.
[6] Cao Y., Liu Q., and Tao L. (2019) Application of Ground Penetrating Radar for Detecting Grouting Quality in Highway Tunnel. 2019 IEEE 8th Joint International Information Technology and Artificial Intelligence Conference (ITAIC).
[7] Rathod H., Debeck S., Gupta R., and Chow B. (2019) Applicability of GPR and a rebar detector to obtain rebar information of existing concrete structures. Case Studies in Construction Materials, 11, e00240. doi:10.1016/j.cscm.2019.e00240.
[8] Lin C., Wang X., Li Y., Zhang F., Xu Z., and Du Y. (2020) Forward Modelling and GPR Imaging in Leakage Detection and Grouting Evaluation in Tunnel Lining. KSCE Journal of Civil Engineering (2020) 24(1):278-294 DOI 10.1007/s12205-020-1530-z.
[9] YuH Z., Ouyang Y.F., and Chen H. (2012) Application of Ground Penetrating Radar to Inspect the Metro Tunnel, in: Proc. of the 14th International Conference on Ground Penetrating Radar (GPR), June 4-8, Shanghai, China.
[10] Tillard, S., and Dubois, J.C., (1995) Analysis of GPR data: wave propagation velocity determination, J. Appl. Geophysics. 77–91.
[11] NPRA Norwegian Public Roads Administration. (2012) Report No. 127. Major Research and Development Project: Modern Road Tunnels 2008-201, NPRA, Oslo (Norwegian)
[12] Selahattin P. (1977) Alucra (Giresun) güneydoğu yöresinin petrol olanakları bakımından incelenmesi, Doçentlik Tezi, KTÜ, Yayın No:87, Trabzon, (yayımlanmamış).
[13] Güven, İ.H., 1993. Doğu Pontidlerin Jeolojisi ve 1/250.000 Ölçekli Kompilasyonu, MTA Yayınları, Ankara.
[14] Rasol M. A., Pérez-Gracia V., Fernandes F. M., Pais J. C., Santos-Assunçao S., Santos C., and Sossa V. (2020) GPR laboratory tests and numerical models to characterize cracks in cement concrete specimens, exemplifying damage in rigid pavement.
[15] Alsharahi G., and Driouach A. (2015) Simulation of Ground Penetrating Radar Imaging Under Subsurface.
[16] Conyers, L. B., and Goodman, D., (1997) Ground-penetrating radar: An Introduction for Archaeologists. California: Altamira Press.

Sigma Mühendislik ve Fen Bilimleri Dergisi-Cover

ISSN: 1304-7191
Yayın Aralığı: Yılda 4 Sayı
Yayıncı: Yıldız Teknik Üniversitesi

Arşiv