立坑巻索の安全率について

抄録

ln this paper we have discussed the Sqfety Factor of Winding Ropes on the ground of the results obtained through our researches, one of which we have already reported in our first and second papers on the longitudinal vibration of winding ropes in vertical shafts, and another of which we have showed in the other paper on the bending stress of wire ropes.
Some results we have obtained through our researches are as follows;
1) The Safety Factor of Winding Ropes in Vertical Shafts, which is stipulated in the Japanese Regulation for Mining Safety, is found imperfect, especially the Value of the 2nd Safety Factor F₂ (dynamic safety factor) is too small to keep the safety of winding ropes, the reason being too small an estimate of sending stress and dynamic pull.
2) The decrease in F₁ in proportion to the depth of a shaft seems to be groundless.
3) We propose a new safety factor of winding ropes in vertical shafts, estimating E_b=20, 000kg/mm²for bending stress and considering the vibration of winding ropes when loaded or braked in a mechanicalmethod.