Preliminary Mechanical Evaluation of Grouting Concrete as a Protective Layer for Tunnelling

The aim of this study is to introduce a protective layer to safeguard tunnel structures. In practice, one viable approach to create this protective layer between the tunnel structure and surrounding rocks is to pump the material during tunnel construction. The primary components of the proposed mate...

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Bibliographic Details
Main Authors: Yi Lu, Tong Wan, Xiangyun Huang, Jiahui Lu, Shan Lin, Xingzhong Nong
Format: Article
Language:English
Published: MDPI AG 2023-07-01
Series:Materials
Subjects:
Online Access:https://www.mdpi.com/1996-1944/16/14/4957
Description
Summary:The aim of this study is to introduce a protective layer to safeguard tunnel structures. In practice, one viable approach to create this protective layer between the tunnel structure and surrounding rocks is to pump the material during tunnel construction. The primary components of the proposed material are porous sand, rubber, and cement. Static and dynamic experiments were conducted to assess the unconfined compressive strength (UCS), flexural stiffness, and compaction resistance at various mixing ratios. The results indicate that the addition of porous sand decreases the UCS compared to the solid sand under similar mixing conditions. The addition of rubber offers the elasticity, thereby enhancing the compaction resistance. However, increasing the rubber content compromises UCS. Furthermore, this study presents a linear equation to predict the 7-day UCS, which can be used as a rapid estimation for UCS, flexural stiffness, and compaction resistance of the proposed material. It is important to note that this study only investigates the fundamental mechanical properties of the proposed material, and further comprehensive research is necessary to fully understand its workability, durability, and other behaviour before practical application.
ISSN:1996-1944