An experimental study to investigate the possibility of using macro-synthetic fibers in precast tunnel segments

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2019
Tengilimoğlu, Oğuz
With the development of tunnel construction techniques, segmental tunnel linings have begun to play a crucial role in preserving ground surfaces and solving traffic problems in metropolitan areas. In parallel with growing interest in precast tunnel lining, engineers are in the Search of solutions that improve precast production efficiency and obtain higher structural performance. Nonetheless, the number of studies related to precast tunnel segments in Turkey is quite limited. Fibers have used as reinforcements in many projects due to significant advantages and nowadays, there is a general interest in the field of civil engineering on macro-synthetic fibers to use in precast tunnel segmental lining. However, it is a controversial issue on whether it is proper or not, compared to the commonly used conventional rebars. Within this framework, experimental studies on full-scale segments of Mecidiyeköy - Mahmutbey metro line project in İstanbul were performed to investigate the possibility of using polypropylene fiber reinforcements with or without using rebars in precast tunnel segments. In these experiments, for reliability and usability of glass fiber reinforced polymer rebars instead of conventional rebars were also investigated. Flexural test was carried out in order to compare the flexural bearing capacity of tunnel segments, also point load test was developed with the purpose of observing the real effect of thrust forces on precast tunnel segments.

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Citation Formats
O. Tengilimoğlu, “An experimental study to investigate the possibility of using macro-synthetic fibers in precast tunnel segments,” M.S. - Master of Science, Middle East Technical University, 2019.