Means (standard deviation in parentheses) for variables of interest: force at the block (FB), tension in the rope (T), force at the block / mass of the piece or top (AccelFB), tension in the rope / mass of the piece or top (AccelT), mass, fall distance, fall factor, and stress. Read down a column, means followed by the same letter are not different (P > 0.05) by Tukey’s studentized range test.
Piece | n | FB (N) | T (N) | AccelFB (m/s2) | AccelT (m/s2) | Mass (kg) | Fall Distance (m) | Fall Ratio | Length of Piece (m) | Stressz (kPa) | Strain (mm/mm) |
---|---|---|---|---|---|---|---|---|---|---|---|
8,783 | 3,347 | 58.5 | 22.4 | 152 | 7.40 | 0.56 | 6.27 | 9,202 | 0.0021 | ||
Top | 13 | (4,303) a | (1,734) a | (9.22) a | (5.19) a | (72.7) a | (1.38) a | (0.10) a | (1.00) a | (6,433) a | (0.0012) a |
5,439 b | 2,152 | 123 | 48.2 | 45.5 | 3.47 | 0.30 | 1.83 | 4,175 | 0.0009 | ||
1 | 13 | (1,960) b | (819) b | (24.0) b | (8.80) bc | (18.0) b | (0.14) b | (0.03) b | (0.00) b | (2,521) b | (0.0005) b |
7,057 | 2,991 | 126 | 52.9 | 58.2 | 3.47 | 0.36 | 1.83 | 5,388 | 0.0011 | ||
2 | 13 | (1,864) abc | (1,110) abc | (22.5) b | (17.6) b | (21.0)b | (0.16) b | (0.05) b | (0.00) b | (3,514) b | (0.0004) b |
7,235 | 2,835 | 113 | 43.2 | 65.6 | 3.48 | 0.45 | 1.83 | 6,437 | 0.0014 | ||
3 | 13 | (2,015) abc | (1,014) abc | (15.2) b | (8.64) c | (22.0) b | (0.16) b | (0.07) c | (0.00) b | (4,010) ab | (0.0006) b |
8,592 | 3,401 | 115 | 47.1 | 77.1 | 3.46 | 0.58 | 1.83 | 6,533 | 0.0014 | ||
4 | 12 | (2,526) ac | (1,038) ac | (22.4) b | (7.40) c | (25.3) b | (0.15) b | (0.10) a | (0.00) b | (4,231) ab | (0.0006) b |
↵zBecause stress was measured both normal and parallel to the direction of fall. the sample size was 25 (23 for piece 4 since one tree only had 3 pieces after the top).