Experimental and mechanical performance of shotcrete made with nanomaterials and fiber reinforcement

• Published in: Construction & building materials Vol. 165; pp. 199 - 205
• Main Authors: Khooshechin, Maryam, Tanzadeh, Javad
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 20.03.2018; Elsevier B.V
• Subjects: Analysis; Building materials durability; Cements (Building materials); Durability; Glass fibers; Gunite; Modified concrete; Nano-Al2O3; Nano-SiO2; Nanotechnology; Properties; Shotcrete; Shrinkage; Shrinkage (Materials); Strength; United States; Nano-Al2O3; Shotcrete; Nano-SiO2; Durability; Shrinkage; Strength; Modified concrete; Glass fibers
• DOI: 10.1016/j.conbuildmat.2017.12.199
• ISSN: 0950-0618

•Nano-SiO2 prevent the diffusion of external destructive factors into the concrete and improve the durability.•Nano-Al2O3 acts as filler for improving the pozzolanic reaction in the concrete.•Limit the durability impact and cracking due to shrinkage effects, sprayable the modified shotcrete.•The effect of glass fiber has been done to prevent cracking, in the shotcrete.•The increase in the flexibility properties of shotcrete due to glass fiber is an important consideration. Studying the application of nanomaterial in cement matrixes is a new subject which has attracted the attention of researchers. Development of engineered cementitious composite has produced a solution to numerous shotcrete application challenges. In this study, mechanical tests were conducted to evaluate the strength of the concrete modified by fibers and nanomaterials in terms of comparison with conventional concrete and shotcrete. It is included in the application of Nano-Al2O3 and Nano-SiO2, which are some of the cement constituent. With proper homogenization, Nano-Al2O3 acts as filler for improving the pozzolanic reaction in the concrete. Nano-SiO2 particles also prevent the diffusion of external destructive factors into the concrete, thus improving the durability and stability of concrete. On the other hand, application of Alkali Resistant (AR) glass fibers improves the tensile and compressive strengths as well as concrete continuity and also resolves the changes created in mechanical properties of the fibers caused by alkaline concrete environment. Test results revealed that the maximum increase in compression and flexural strengths of modified concrete were 20.6 and 52%, respectively of its optimum compounds for 0.7% glass fiber with 1% Nano-Al2O3 and 1.5% Nano-SiO2, while in the modified shotcrete, these values were increased by 22.9 and 75%, respectively. In addition, application of the mentioned materials led to decrease of penetration depth and water absorption of the modified concrete by 46.78 and 2.5%, respectively, in relation to the conventional concrete. Also, addition of fibers and nanomaterials in shotcrete reduced the effect of cracking due to shrinkage and the modified shotcrete material rebound.