Abstract
The authors' study contains several discussions on the collapse modes and the final capacities of arches. In the design of arches, the elastic arch theory is applied to high arches and the straight beam theory to arches with very low rises. As well known, when the elastic arch theory is adopted for the latter, engineers face difficulties in design because of extremely high thrusts. The authors try to get rid of this discrepancy in the elastic design method of arches from the standpoint of limit design. As the result of research on the final states of arches earring a concentrated load or uniformly distributed load due to yield condition formula (Eq. I. 1), it is clarified that there are several collapse modes in arches and the mode changes from to others with vary rise and final coincides with that of the straight beam. The influence of eccentricity of concentrated load, that of depth of section to the final capacities and the collapse modes of arches, and the comparison on the final states between built-in, 2 hinged and 3 hinged arches were explained too. This paper treated the case of arches earring concentrated load as Part 1 of this study. The case carring uniformly distributed load and a practical method of the limit design will be described in Part 2.