Fibre-reinforced post-tensioned anchorage zone An experimental comparison of reinforcement configurations
Typ
Examensarbete för masterexamen
Master's Thesis
Master's Thesis
Program
Structural engineering and building technology (MPSEB), MSc
Publicerad
2024
Författare
Bengtsson, Ludwig
Nordek, Anton
Modellbyggare
Tidskriftstitel
ISSN
Volymtitel
Utgivare
Sammanfattning
Prestressed concrete enables the design and construction of long-span, slender, and
economical concrete structures. In post-tensioned concrete structures, the anchorage
zones are critical details, which normally end up both heavily reinforced and
labour-intensive while following the manufacturer’s European Technical Assessment
(ETA) approval for additional reinforcement and applicable design procedures. The
upcoming Eurocode will permit the design of these regions using steel fibre reinforced
concrete (SFRC). This master’s thesis presents an experimental comparison
of three different post-tensioned anchorage zones: a conventionally designed anchorage
zone made of reinforced concrete and ETA-approved helical bursting, an SFRC
anchorage zone equipped with ETA-approved helical bursting reinforcement, and an
SFRC anchorage zone.
The anchorage zones are designed according to the applicable Eurocode, upcoming
Eurocode and course literature. The final design of the specimens, representing
anchorage zones, was validated by a non-linear finite element analysis in the softward
Diana 10.8 to ensure the desirable structural response. Two specimens of each
anchorage design were constructed and equipped with 3D-printed plastic spirals to
support the distributed optical fiber sensors (DOFS). The specimens were tested
experimentally by subjecting them to centric compressive loading. The configurations
were evaluated and compared by analysing the data obtained from the DOFS,
Digital Image Correlation (DIC), and load-deformation response.
The comparison between DOFS measurements and DIC has shown that the proposed
fiber optics arrangement enabled the assessment of the specimens’ structural
response with high accuracy. According to the results, the plain SFRC configuration
exhibits the largest strains and crack widths of the three configurations. Incorporating
helical bursting reinforcement in SFRC significantly improved the structural
response by decreasing the measured strains and crack widths. The reference configurations
exhibited the lowest strains and smallest crack width while maintaining
the highest consistency in the structural response.
The findings in this master’s thesis will likely provide further knowledge and enhance
the contemporary design for post-tensioned anchorage zones.
Beskrivning
Ämne/nyckelord
Post-tensioned concrete, Anchorage zone, Steel fibre reinforced concrete, Distributed optical fiber sensing, Digital Image Correlation, DIC, Crack monitoring