Strength of beam flange to circular tube column joint by exterior diaphragm type connection

This paper addresses the derivation of collapse load of beam flange to circular tube column connections with exterior diaphragm based on plastic analysis. In order to verify the validity of the derived collapse load, component tests of the connections were conducted. Major findings obtained from tests are summarized as follows: (1) the yield strength obtained from the tests was about 80 to 90% of the calculated collapse loads, (2) the local deformation of the circular tube column that corresponds to the calculated collapse load is small enough for the yield strength, (3) the derived collapse load formula which is considering the shape of the connections correlated well with the test results, and captured the trend in a reasonable manner, (4) the maximum strength obtained from the tests was about 110 to 120% of the calculated maximum loads.