Page 320 - 360.revista de Alta Velocidad - Nº 5

Sol-Sánchez, Miguel. Moreno-Navarro, Fernando. Rubio-Gámez, Mª Carmen.

Figure 3. Influence of rubber dosage to modify track performance in reference to conventional stoneblowing, comparing to the
effect of USPs.
Regarding the effect of stone-rubber blowing on the settlement trend of the whole track section after
maintenance intervention, Figure 4 represents the reduction in total settlement at the end of the test as well as
the ratio of settlement per load cycle, in reference to the conventional stoneblowing process. Also, results are
compared to those measured when USPs are used as control to analyse the effect of the flexible aggregates.
Results demonstrate that the inclusion of rubber particles during stoneblowing intervention leads to
a positive effect on track geometry by reducing cumulative ballast settlement, this fact being more
remarkable when increasing the quantity of rubber applied. In comparison to the impact of USPs, it is
seen that the quantities of rubber that led to a comparable change in track performance (10% and 50% of
rubber in reference to stiff and soft USPs, respectively), allow for a higher reduction in track settlement
at the end of the test, and what is more remarkable, a reduction in the long-term trend to settlement.
This implies that incorporating rubber particles during stoneblowing seems to be more effective than the
application of USPs, which could reduce the need for high-frequency maintenance checks.

Figure 4. Effect of including elastic solutions to improve the effectiveness of stoneblowing process on reducing track
settlement.

318 360.revista de alta velocidad