Evaluation of Shotcrete Performance Enhancement Using Bio-Admixture

DOI

10.2991/978-94-6463-900-1_14How to use a DOI?

Keywords

Bio-admixture; Shotcrete; Retarder; Strength enhancer

Abstract

Shotcrete is widely used in tunnelling and mining as a surface support element. Admixtures can modify the properties of fresh or hardened concrete, or in some cases, both, to meet the varying demands of different applications. The production of traditional chemical admixtures not only consumes significant amounts of energy and generates pollution but also results in the formation of some toxic by-products. To explore more sustainable alternatives, this study introduces varying concentrations of carrot juice as a bio-admixture during the mixing process and evaluates its effect on the mechanical properties of shotcrete. The control group consisted of plain shotcrete with a water-to-shotcrete powder ratio by weight of 14%. Three additional groups replaced an equivalent weight of water with carrot juice, with carrot juice-to-shotcrete powder ratios by weight of 0.14%, 0.28%, and 0.55%, respectively. The total liquid-to-shotcrete powder ratio by weight remained constant at 14%. The results demonstrate that carrot juice significantly retards the hydration process of cement and enhances the workability of shotcrete. Mechanical tests indicate that Group 3 improves the Uniaxial compressive strength (UCS) at every test curing age and indirect tensile strength at 28 days of curing. Direct pull-off tests conducted on basalt and sandstone reveal that carrot juice effectively enhances the bond strength at the rock-shotcrete interfaces. Carrot juice has the potential to be widely adopted as a bio-admixture for shotcrete, as it improves the mechanical strength of shotcrete and offers a more sustainable and environmentally friendly alternative to chemical admixtures.

Copyright

© 2025 The Author(s)

Open Access

Open Access This chapter is licensed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (http://creativecommons.org/licenses/by-nc/4.0/), which permits any noncommercial use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license and indicate if changes were made.

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TY  - CONF
AU  - Kunze Li
AU  - Hamed Lamei Ramandi
AU  - Selahattin Akdag
AU  - Hamish Windybank
AU  - Ned Cooper
AU  - Chengguo Zhang
AU  - Serkan Saydam
AU  - Joung Oh
PY  - 2025
DA  - 2025/12/07
TI  - Evaluation of Shotcrete Performance Enhancement Using Bio-Admixture
BT  - Proceedings of the Rocscience International Conference 2025 (RIC 2025)
PB  - Atlantis Press
SP  - 141
EP  - 149
SN  - 2589-4943
UR  - https://doi.org/10.2991/978-94-6463-900-1_14
DO  - 10.2991/978-94-6463-900-1_14
ID  - Li2025
ER  -