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Updated: Aug 5, 2026
11:07
Preparation of Aligned Steel Fiber Reinforced Cementitious Composite and Its Flexural Behavior
Published on: June 27, 2018
Development of Cross-Scale Structured Hybrid Fiber-Reinforced Shotcrete
Mengmeng Liu1, Lu Zhang2, Xiaoou Zhang1
1School of Architecture and Civil Engineering, Xihua University, Chengdu 610039, China.
Materials (Basel, Switzerland)
|July 28, 2026
Summary
This study enhances shotcrete performance for tunnels using hybrid fibers and carbon nanotubes (CNTs). The optimized mix significantly boosts mechanical strength and reduces rebound, improving underground excavation safety.
Area of Science:
- Materials Science
- Civil Engineering
- Geotechnical Engineering
Background:
- Tunnel construction faces challenges in extreme geological conditions, increasing demands on shotcrete performance.
- Conventional shotcrete requires enhancement for high geo-stress, rock bursts, and fault zones.
Purpose of the Study:
- To develop and evaluate a novel cross-scale structured hybrid fiber-reinforced shotcrete.
- To investigate the impact of alkali-resistant glass fibers (HP and HD types) and carbon nanotubes (CNTs) on shotcrete properties.
Main Methods:
- Employed an orthogonal experimental design (four factors, four levels) to optimize fiber and CNT content.
- Assessed mechanical properties (compressive strength, tensile strength, slump, rebound) and microstructure (SEM) at 3, 7, and 28 days.
Main Results:
- Identified optimal mix: 4% HP fiber (24 mm), 2% HD fiber (18 mm), 2% HD fiber (6 mm), and 0.2% CNT.
- Achieved 28-day compressive strength of 43.53 MPa and splitting tensile strength of 4.85 MPa.
- Reduced rebound rate to 3.85% with enhanced mechanical properties.
Conclusions:
- The hybrid fiber and CNT reinforcement provides a multi-scale mechanism for crack suppression and interfacial zone densification.
- The developed shotcrete offers superior performance for complex underground excavations.
- Provides a parametric reference for high-performance shotcrete in demanding engineering applications.
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