Fiber optic sensors type LPG applied to the determination of stresses and deformations in soils
DOI:
https://doi.org/10.21754/tecnia.v28i1.182Keywords:
Long-period fiber grating, fiber optic sensors, Soil stressAbstract
This paper shows the application of LPG optical fiber sensors to the determination of the transmitted stress and deformation of a sample of confined soil subjected to surface loads. The transmitted stress was measured by a mechanical LPG pressure sensor and the curvature of the ground by permanent LPG sensors buried at depths of 0.1m; 0.2m; 0.4m and 0.6m. Clay-sandy soil characteristic of UNICAMP was deposited in a cylinder of 0.8m in length and 0.30m in diameter. The soil was lightly compacted in 0.2m layers and an LPG sensor was installed on each layer. Surface loads of up to 227 KPa were applied to the surface of the soil, measuring axial soil deformations of less than 3mm by our sensors with sensitivities of the order of 0.22 mm/dB. The values of the modulus of elasticity for this type of soil were determined from the fitting of the Bousinessq equations with the values measured by the buried LPG sensors. A Young's modulus of 5.39 MPa and a Poisson's coefficient ν = 0.52 were determined for this type of soil.
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[2] E. A. Novikov, V. L. Shkuratnik, R. O. Oshkin, and M. G. Zaitsev, Effect of the stress-strain state of sandy-clay soils on their thermally stimulated acoustic emission. Osnovaniya, Fundamenty ¡ Mekhanika Gruntov, No. 2, pp. 12-17, March-April, 2017
[3] Sunita Mishrai, Tanusree Chakraborty, Dipanjan Basu. High strain rate stress-strain response of soils- A review. International Workshop on Geotechnics for Resilient Infrastructure. The Second Japan-India Workshop in
Geotechnical Engineering. Volume 3 (2016) Issue 2 Pages 80-85 http://doi.org/10.3208/jgssp.v03.i13
[4] Hien Nghiem, Nien-Yin Chang. Soik-Structure Interaction Effects of High Rise. Buildings. International Conference on Case Histories in Geotechnical Engineering. 30. (2008) http://scholarsmine.mst.eduficchge/Gicchge/session_01/30.
[5] Gerd Gudehus. Physical Soil Mechanics. Springer-Verlag 2011.
[6] Paulo José Rocha de Albuquerque. Analysis of Behavior of Small Diameter Pre-Molded Stake, Instrumentated, in Soil Residual of Diabásio of the Campinas Region. Master's thesis in Agricultural Engineering. UNICAMP/ Brasil (1996).
[7] M. Navarrete F. A. Godínez, M. Villagrán Muniz. Elastic Properties of Compacted Clay Soils by Laser Ultrasonics. Int J Thermophys Received: 9 February 2012 / Accepted: 5 January 2013 © Springer Science+Business Media New York 201. Doi 10.1007/510765-013-1389-z
[8] Américo Hossne García. Sandy loam savanna soil elastoplasticity. SABER. Revista Multidisciplinaria del Consejo de Investigación de la Universidad de Oriente, vol. 26, núm. 2, abril-junio, 2014. Cumaná, Venezuela.
[9] Namkwon , Jaewon Song, and Jaehee Park. Mechanically Induced Long Period Fiber Grating Array Sensor. Microwave and Optical Technology Letters / Vol. 53, No. 10, October 2011.
[10] Marrujo García Sigifredo et all. Temperature sensing on tapered single mode fiber using mechanically induced long period fiber gratings. Proc.of SPIE Vol. 9577, 95770K · © 2015 SPIE. doi: 10.1117/12.2186505.
[11] L Mosquera et all. High sensitivity LPG Mach-Zehnder sensor for real-time fuel conformity analysis. Meas. Sci. Technol. 24 (2013).
[12] L Mosquera, Jonas H Osório and Cristiano M B Cordeiro. Determination of Young's modulus using optical fiber long-period gratings. Meas. Sci. Technol. 27 (2016) 015102 (6pp).
[13] Yiping Wang. Review of long period fiber gratings written by CO2 laser. Journal of Applied Physics 108, 081101- 2010.
[14] J. S. Hallett, M. Partridge , S.W. James, D. Tiwari, T. Farewell, S. H. Hallett, and R. P. Tatam. Soil Moisture Content Measurement Using Optical Fiber Long Period Gratings. 25th International Conference on Optical Fiber Sensors, Proc. of SPIE Vol. 10323, © 2017 SPIE. doi: 10.1117/12.2263427.
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