Program Results and Discussion

Statically Determinate Beam Test

As demonstrated in Table 5, 5creep,m in the programs A1 and A2 of the PFRC specimens is 2-4 times that of the SFRC specimens. In program A1, all PFRC specimens show an exponential deformation increase and 5 out of 6 specimens eventually fail (Fig. 3). However, the rate of creep is not so easy to predict as can be concluded from program A2 (Fig. 4) where both tested PFRC with identical dosage show very different results. It should therefore be concluded that big variations can be found among polymer fibres. These differences cannot be explained by their material properties alone; shape and surface geometry might also play a role.

According to the results found in program A3 (Fig. 5), one could conclude that the 3D fibres and the 5D fibres show the same behaviour. However, as the wire strength in a 5D fibre is much higher and also much more utilized, the 5D anchor and the concrete compression zone has to withstand a higher actual load. With an increasing Fcreep, deflections are expected to be higher. However an overall rise in 5creep,m could not observed.

In all programs, fluctuations can be observed in the registered 5creep. These fluctuations are in this case attributed to variations in temperature and relative humidity in the test room.

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