| Popis: |
Turf racetrack traction is mainly a function of bearing strength of the underlying soil. The relationship between the pene-trometric index of bearing strength and traction, reflected in times run by horses, differs with soil type. A method has been developed to take account of soil type differences. A hyperbolic model was used to relate penetrometer index to racetimes for 2300 races on 29 racetracks. The model normalised all data to a standard 1400 metre race. Adjustments were made to account for the effect of racetrack configuration, soil type, class of horse, distance and the effect of rain on three main parameters: m-the winners time for a standard race (83,45 sees) expected on an ideal (best traction) track; a-the penetrometer index (2.40 cm for the standard race) above which times increase; and b-the maximum increase in time (standard of 2.78 sees cm') for a unit increase in penetration. The tuning point parameter, a, and the slope parameter, b, were fitted as a base value for the standard r... |
