Open Access

ARTICLE

Numerical Analysis of Three-Layer Deep Tunnel Composite Structure

by Weiwei Sun¹, Hongping Min², Jianzhong Chen^1,*, Chao Ruan², Yanjun Zhang², Lei Wang³

1 Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics, School of Science, Wuhan University of Technology, Wuhan, 430070, China
2 China Construction Third Bureau Green Industry Investment Co., Ltd., Wuhan, 430035, China
3 Fujian Lutong Pipe Technology Co., Ltd., Quanzhou, 362000, China

* Corresponding Author: Jianzhong Chen. Email:

(This article belongs to the Special Issue: Modeling of Heterogeneous Materials)

Computer Modeling in Engineering & Sciences 2021, 127(1), 223-239. https://doi.org/10.32604/cmes.2021.015208

Received 01 December 2020; Accepted 28 December 2020; Issue published 30 March 2021

Abstract

To date, with the increasing attention of countries to urban drainage system, more and more regions around the world have begun to build water conveyance tunnels, sewage pressure deep tunnels and so on. However, the sufficient bearing capacity and corrosion resistance of the structure, which can ensure the actual service life and safety of the tunnel, remain to be further improved. Glass Fiber Reinforced Plastics (GFRP) pipe, with light weight, high strength and corrosion resistance, has the potential to be applied to the deep tunnel structure. This paper proposed a new composite structure of deep tunnel lined with GFRP pipe, which consisted of three layers of concrete segment, cement paste and GFRP pipe. A new pipe-soil spring element model was proposed for the pipe-soil interaction with gaps. Based on the C3D8R solid model and the Combin39 spring model, the finite element numerical analysis of the internal pressure status and external pressure stability of the structure was carried out. Combined with the checking calculation of the theoretical formula, the reliability of the two finite element models was confirmed. A set of numerical analysis methods for the design and optimization of the three-layer structure was established. The results showed that from the internal GFRP pipe to the outer concrete pipe, the pressure decreased from 0.5 to 0.32 MPa, due to the internal pressure was mainly undertaken by the inner GFRP pipe. The allowable buckling pressure of GFRP pipe under the cover of 5 GPa high modulus cement paste was 2.66 MPa. The application of GFRP pipe not only improves the overall performance of the deep tunnel structure but also improves the construction quality and safety. The three-layer structure built in this work is safe and economical.

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Keywords

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