Measurement of Axial Strain of Geogrid by Optical Sensors

Abstract

In recent years, the technology of optical fibers has rapidly gained ground in many areas of science and industry, including the construction industry. In this article, the technology of optical fibers based on a fiber Bragg grating (FBG) was used to determine tensile forces acting in a basal reinforcement of a scaled down physical model, which included piled embankment and basal reinforcement. Installing FBG sensors on the geogrid made monitoring of axial strains possible, thus allowing determination of the behavior of the basal reinforcement of the piled embankment. On the basis of three tests performed on the physical model, numerical model calibration with the physical model was carried out using the software PLAXIS 3D Tunnel 2.4. The results showed accurate predictions, especially for the low and middle part of the measured deformations where the numerical analysis proposed a solution that can be considered as safe. Installing FBG sensors on biaxial geogrids was a bold idea that was not easy to implement. However, other possibilities have been successfully tested, such as high-frequency measurements of the response of reinforced soil structure under dynamic loading.

Analysis of a Large-Scale Physical Model of Geosynthetic-Reinforced Piled Embankment and Analytical Design Methods

“…The measurements of strain were made using sensors based on Fiber Bragg Grating technology (FBG sensors) at the points indicated as O1 and O2 (Figures 10 and 12). The sensor O1 was situated in the strip between the adjacent piles where the major load is assumed according to the studies [13,14] and [49][50][51]. The sensor O2 was placed on the diagonal between the piles.…”

The Formative Factors of a Rock Burst Based on Energy Calculations and the Experimental Verification of Butterfly-Shaped Plastic Zones

“…In terms of dynamic disasters, coal mine rock burst accidents have occurred more frequently in China in recent years, bringing huge pressure to safety production. The study of the mechanism of geotechnical engineering disasters is a fundamental work that can provide direction for subsequent monitoring [7,8], warning [9], and evaluation [10].…”