Laboratory Investigation of the Mechanical Properties of a Rubber–Calcareous Sand Mixture: The Effect of Rubber Content
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Department of Geological Engineering, School of Geological Engineering and Geomatics, Chang’an University, Xi’an 710054, China
2
LREIS, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100864, China
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Authors to whom correspondence should be addressed.
Appl. Sci. 2020, 10(18), 6583; https://doi.org/10.3390/app10186583
Received: 28 July 2020 / Revised: 2 September 2020 / Accepted: 14 September 2020 / Published: 21 September 2020
(This article belongs to the Special Issue Advances in Geotechnical Engineering)
This paper introduces a rubber–calcareous sand mixture as a lightweight building material in offshore engineering. The mechanical properties of mixtures of varying rubber contents were investigated by performing a one-dimensional (1-D) compression test in a modified oedometer cell, as well as a resonant column test. A discussion on the test results, along with detailed interpretations regarding the role of rubber chips in the mixtures, are provided. It was found that the virgin compression curves of the rubber–calcareous sand mixtures tended to converge at a certain stress level, whilst the stress level depended on the rubber content. Moreover, the relative breakage was examined by comparing the particle size distribution curves of the calcareous sand before and after the compression test. It was shown that the grain crushing of calcareous sand was less remarkable with the inclusion of rubber chips. Furthermore, the small strain shear modulus (G0) of the mixtures decreased with the rubber content, yet the modulus reduction and damping curves exhibited little difference for the specimens of varying rubber contents.