ILLUSTRATIONS - continued

TR-01-16
Page Navigation
4

61. Modeled resistance force in coefficient form (longitudinal/vertical) and vertical dis-

62. Finite element model, measured data, and NRMM predictions

for sinkage and motion resistance in fresh snow ................................................... 47

63. Finite element simulations at zero slip and at unlimited slip

64. Marking the snow to observe snow deformation after vehicle passage ................. 49

65. Comparison of measured displacement to modeled displacement

66. Comparison of measured and modeled displacement

67. Comparison of measured and modeled densities

68. Rolling tire on an elastic material (sand). .............................................................. 52

69. Rolling ShoopDarnell tire on a DruckerPrager cap model

70. Deformed mesh of modal analysis tire model in snow after 8 cm of sinkage ....... 54

71. Close-up of a tire after sinking 8 cm into the snow at the beginning of roll .......... 54

TABLES

Table

1. Initial material model parameters ..........................................................................

2. Pressurevolume data calculated from the Abele and Gow (1975) data set

3. Hardening table for fresh snow with a density of 200 kg/m3 .................................

4. Material constants for DruckerPrager cap model of McCormick Ranch sand .....

5. Hardening model for McCormick Ranch sand (HKS, 1996) .................................

6. Tire characteristics for test tires at an average vertical load of 6227 N .................

7. Bending stiffness of tire sections ...........................................................................

8. Properties of sidewall elements and tire model components .................................

9. Features of the modal analysis models with smooth and straight ribbed tread ......

10. Qualitative summary of runtime analysis ..............................................................

11. Measured sinkage and resistance in snow .............................................................