[1] Li Wensheng, Wu Gang, Dong Zhiqiang, Wang Shuying, et al. Experimental study on a pre-damaged scaled tunnel modelstrengthened with CFRP grids [J]. Journal of Southeast University (English Edition), 2017, 33 (2): 196-202. [doi:10.3969/j.issn.1003-7985.2017.02.012]

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Experimental study on a pre-damaged scaled tunnel modelstrengthened with CFRP grids()

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Journal of Southeast University (English Edition)[ISSN:1003-7985/CN:32-1325/N]

Volumn:

33

Issue:

2017 2

Page:

196-202

Research Field:

Materials Sciences and Engineering

Publishing date:

2017-06-30

Info

Title:

Experimental study on a pre-damaged scaled tunnel modelstrengthened with CFRP grids

Author(s):

Li Wensheng¹;  Wu Gang²;  Dong Zhiqiang²;  Wang Shuying²

¹Electric Power Research Institute of Guangdong Power Grid Co., Ltd., Guangzhou 510080, China
²Key Laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education, Southeast University, Nanjing 210096, China

Keywords:

carbon fiber reinforced polymer(CFRP)grid;  double-shear bond test;  surface treatment;  scaled tunnel model;  relative displacement

PACS:

TU502

DOI:

10.3969/j.issn.1003-7985.2017.02.012

Abstract:

The effectiveness of carbon fiber reinforced polymer(CFRP)grids as the strengthening materials for a pre-damaged scaled tunnel model is experimentally investigated. First, the bond performances between the CFRP grid and the concrete under different types of adhesive and surface treatment were tested. The most efficient anchoring system was adopted for the subsequent scaled tunnel strengthening. Test results show that when the epoxy structural adhesive was used as the bonding material, the failure mode was CFRP grids rupturing, and the anchorage performance was optimal. When the polymer mortar was used as the adhesive, the surface treatments with anchored bolts and grooves can improve the bond performance, and the failure mode was sliding failure with the polymer mortar peeled off. After strengthening with CFRP grids, both the stiffness and the load capacity of the pre-damaged scaled tunnel model were improved. Additionally, the results obtained by fiber bragg grating(FBG)sensors indicate that the strains across tunnel segments were reduced, and the overall performance of the tunnel was improved.

References:

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Memo

Memo:

Biographies: Li Wensheng(1984—), male, doctor; Wu Gang(corresponding author), male, professor, g.wu@seu.edu.cn.
Foundation items: The Science and Technology Project of China Southern Power Grid Co., Ltd.(No.GDKJ00000030), the National Key Technology R&D Program of China(No.2016YFC0701400), the National Natural Science Foundation of China(No.51525801).
Citation: Li Wensheng, Wu Gang, Dong Zhiqiang, et al. Experimental study on a pre-damaged scaled tunnel model strengthened with CFRP grids[J].Journal of Southeast University(English Edition), 2017, 33(2):196-202.DOI:10.3969/j.issn.1003-7985.2017.02.012.

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