温州みかんの流通技術改善に関する研究 (第3報)

早生温州の力学的性質とバラ輸送問題への適応

抄録

For the purpose of designing a container which would be used for transporting bulk Citrus Unshu the mechanical properties of Citrus Unshu were measured under the static or dead load, the quasi-static load and the impact load respectively, and the follwing results were obtained.
(1) Under the quasi-static load which was produced by a plate and a plunger, the faster the loading rate, the larger the compressive strength. The compressive strength and energy required to rupture the Citrus Unshu (rupture energy) became lower in the stage of maturity after the first decade of November.
At the loading rate of 50mm/min. when using the plate and plunger, the averege rupture energy was 9.80kg·cm and 1.87k·cm respectively.
(2) Under the static load, the mechanics of the force-deformation relationship was a creep phenomenon. The acceptable static load in 60 to 70 hours without rupture was 5kg. The rupture energy under the static load was 7kg·cm.
(3) To predict the creep phenomenon the best known rheological model which was composed of a slider in series 4-element was used.
If the deformation of plastic flow expressed by a slider is 0.62cm, the parameters of this model run as follows; G₁=5.17kg/cm, G₂=10.0kg/cm, η₂=79.6kg·h/cm and η₃=1100kg·h/cm.
(4) The larger the Citrus Unshu, the more durable against the falling impact. The rupture energy under the falling impact was 21.3kg·cm cmwhich was 3.05 times and 2.18 times as that under the static load and the quasi-static one respectively
(5) To predict the maximum impact acceleration within the dropping height of 20cm, Hertz's theory for elastic body was available.