PSI - Issue 42

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Makashev Kuanysh et al. / Procedia Structural Integrity 42 (2022) 769–776 Author name / Structural Integrity Procedia 00 (2019) 000 – 0 0

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Fig 5. Typical failure modes a) M1; b) M2; c) M3; d) M4 mortar.

4. Discussion The main discussion in this section considers the comparison four mortars used in case of a constant bond length of 150mm. Changing the water mortar ratio did not demonstrate improvement as the maximum load increased only by 7.5 %. However, the matrix became more robust, and detachment occurred partially. The in-house made matrix also had not raised peak load, a correction made for 10%. Contrary to M1 mortar, the failure mechanism initiates with cracks in the mortar matrix followed by slippage of the fibres. Fibre-reinforced mortar demonstrated promising alternatives to M1 mortar. The mortar shows appropriate adhesion between matrix and textile. This can be explained as randomly distributed fibres in the mortar matrix alloys textile with matrix, like anchors. However, the bond between TRM and substrate became the weak link in this strengthening technique. As a result, all specimens strengthening with M4 mortar failed due to debonding at the matrix-to-substrate. It shows the need to substrate preparation before strengthening. 5. Conclusion In this paper, experimental work was undertaken to investigate the TRM to masonry bond strength. The main aims of these experiments were to examine the effect of the mortar matrix influence. The results obtained from the experiments can be summarized as shown below: • For the case of M1 mortar, the effective bond length is higher than 150mm. Mortar can not fully utilize the fibre potential. • In cases of M2 and M3, failure occurs in multiple phases following step by step fracture of the mortar