Figure 39. The filtered bogie acceleration history sampled at 3200 Hertz is significantly different from the history sampled at 10,000 Hertz. Graphs A and B.

1. Calculated acceleration histories. This graph shows four distinct lines. The first line is colored light blue and is labeled Unfiltered, ten thousand samples per s second. The second line is colored dark blue and is labeled Filtered, ten thousand samples per second. The third line is colored orange and is labeled Unfiltered, thirty-two hundred samples per second while the four and final line is colored red and is labeled Filtered, thirty-two hundred samples per second. The vertical axis of this graph ranges from negative .20 to 0.20 and represents Acceleration in miles per second while the horizontal axis of this graph ranges from zero to 20 and represents time in milliseconds. The first line, the light blue line oscillates heavily at the beginning between negative .20 and positive .20 on the vertical axis, with the oscillation gradually growing weaker as the line runs across the graph leaving the graph at the point of 0.00 on the vertical axis and 20 on the horizontal axis.The second line, the dark blue line begins at the point of negative 0.03 on the vertical axis and zero on the horizontal axis where it then runs across the graph in a slight wave until it leaves the graph at the point of negative 0.01 on the vertical axis and 20 on the horizontal axis. The third line, the orange line oscillates lightly at the beginning between negative .20 and positive .20 on the vertical axis, with the oscillation gradually growing weaker as the line runs across the graph leaving the graph at the point of 0.00 on the vertical axis and 20 on the horizontal axis. The fourth and final line, the red line, begins at the point negative 0.05 on the vertical axis and zero on the horizontal axis where it hen slopes down to the point of negative 0.12 on the vertical axis and 5 on the horizontal axis. From this point, the line then ascends, sloping upwards and off the graph at the point of negative 0.01 on the vertical axis and 20 on the horizontal axis.

2. Calculated force-deflection histories. This graph shows three distinct lines. The first line is solid yellow and is labeled Grade 1 Southern Yellow Pine test 657. The second line is solid blue and is labeled Rigid bogie, ten thousands samples per second. The third and final line is solid red and is labeled Rigid Bogie, thirty-two hundred samples per second. The vertical axis of this graph ranges from negative 50 to 150 and represents Force in kilonewtons while the horizontal axis of this graph ranges from 0 to 180 and represents Deflection in millimeters. All three lines begin at the points of zero on both the vertical and horizontal axes. The first line, the yellow line, ascends from its starting point in a slope to 50 on the vertical axis and 80 on the horizontal axis where it then slopes back down and off the graph at the points of negative 20 on the vertical axis and 180 on the horizontal axis. The second line, the blue line, ascends from its starting point to 50 on thee vertical axis and 35 on the horizontal axis where it then descends in waves until it leaves the graph at the points of zero on the vertical axis and 180 on the horizontal axis. The third and final line, the red line, ascends from its starting point to 125 on the vertical axis and 50 on the horizontal axis where it then slopes down and off the graph at the points of negative 10 on the vertical axis and 180 on the horizontal axis.

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FHWA-HRT-05-096