板状鉱柱の厚さと空洞幅の比の決定について
1973 年 89 巻 1027 号 p. 593-598
詳細
1973 年 89 巻 1027 号 p. 593-598
The width ratio of rib pillars to openings is an important factor to be taken into consideration on designing large stapes. The present paper describes how to determine it on the assumption that the maximum stress in pillars at such a stage that full plastic deformation has occurred over the portions of stress concentration, should not exceed the allowable compressive strength of pillars.
First the pillar stresses were analyzed both by two-dimensional and three-dimensional ways, on the results of which some modifications were made by considering the results of model experiments. Then Eqs.(10) and (11) derived from the results obtained were proposed for use in determining the maximum stress.
The applicability of this method was proved by the governmental committee on mine safety, with the result that if allowable stress is estimated at one-third of the core strength, these equations to determine the maximum stress can be applied.
