Measuring the Full-Field Strain Response of Uniaxial Compression Test Specimens Using Distributed Fiber Optic Sensing

Autor: Mark S. Diederichs, Nicholas Vlachopoulos, S. Hegger, T. Poles
Rok vydání: 2021
Předmět:
Zdroj: Rock Mechanics and Rock Engineering. 55:2615-2630
ISSN: 1434-453X
0723-2632
DOI: 10.1007/s00603-021-02643-4
Popis: The uniaxial compressive strength (UCS) test is crucial in determining the strength and stiffness behavior of intact rock and is frequently utilized by industry to determine project site characteristics. A fundamental procedure of UCS testing is strain response measurement. Conventionally, discrete strain measuring devices such as extensometers and/or electric foil strain gauges are used to measure the strain response at the mid-height of a specimen. However, this ultimately limits the ability to capture full-field strain of UCS test specimens. This has led to a gap in knowledge in terms of the complexities of UCS test strain responses caused by factors such as specimen heterogeneity and the influence of platen friction. Within this context, a novel distributed optical strain sensing (DOS) technology has been integrated with UCS testing (DOS-UCS technique). Unlike conventional discrete strain measurement methods, the optical technique captures a distributed strain profile along the length of standard, low-cost single mode optical fiber with a spatial sampling resolution of 0.65 mm. By wrapping an optical strain sensor around a UCS specimen, continuous full-field strain profiles along the length and circumference of UCS specimens can be realized. This paper presents a laboratory investigation that illustrates the potential of this technology to provide an in-depth look into the strain response of heterogeneous nodular limestone during UCS testing.
Databáze: OpenAIRE
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