Assessment of Vibration Injury to Bartlett Pears

Laboratory tests revealed that palletized fiberboard boxes of Bartlett pears are most susceptible to bruising damage at vibrational frequencies below 40 Hz (cycles/s), which are common in refrigerated highway trailers. Damage studies indicate that of the four frequency regions observed in-transit (3.5 Hz, 9 Hz, 18.5 Hz, and 25 Hz), Bartlett pears are most severely damaged at 3.5 Hz and 18.5 Hz. Laboratory studies also show that fiberboard boxes of pears amplify vibration at frequencies below 40 Hz such that, for some frequencies, the lid of the top box in a pallet is accelerated three to four times more than the level input to the bottom box.