Flexural Toughness of Basalt Fibre-Reinforced Shotcrete and Industrial-Scale Testing. (31st October 2019)

• Record Type: Journal Article
• Authors: Jiao, Huazhe; Wu, Yachuang; Chen, Xinming; Yang, Yixuan
• Other Names: Criado María Academic Editor.
• Is Part Of: Advances in materials science and engineering. Volume 2019(2019)
• Publication Date: 2019-10-31
• Subjects: Materials science -- Periodicals; Materials science; Periodicals; 620.11
• DOI: 10.1155/2019/6568057
• Languages: English
• ISSNs: 1687-8434

Abstract

Abstract : This study focuses on toughness enhancement of basalt fibre-reinforced shotcrete (BFRS). Four-point bending experiments of underground shooting and curing beams combined with a roadway-supporting deformation monitoring test were conducted. The flexural performance was analysed based on the toughness standards, namely, DBV-1998, JSCE SF-4, and nuclear magnetic resonance (NMR) pore testing. The results demonstrate that, given a basalt fibre (BF) dosage of 0–7.5 kg/m 3, 18 mm BF can significantly increase the residual stress under the same deformation, rather than the peak values of the flexural strength. Meanwhile, the trend in the flexural toughness increases to a peak at a dosage of 3–4.5 kg/m 3, followed by a declining curve. The pores from an NMR test can be divided into three types based on size: (1) closed pores, R < 0.01 μ m, (2) capillary pores, 0.01 μ m < R < 5 μ m, and (3) connected pores, R > 5 μ m. The connected pores are detrimental, playing a crucial role in the shotcrete performance. Furthermore, the deformations of the roadway walls are significantly restrained by the BFRS, and the 80-day convergences are approximately 2 mm, which is only 25% of the control. Finally, the comprehensive results indicate that a dosage range of 3–4.5 kg/m 3 can demonstrate reasonable beneficial effects for the BFRS performance.