STUDY ON THE SEISMIC BEHAVIOR AND NORMAL SECTION BEARING CAPACITY CALCULATION OF THE JOINTS OF LOCAL ENCASED STEEL TUBULAR ASSEMBLY COLUMN

Five cast-in-place columns and the seven local steel tubular assembly columns were tested by using the quasi-static trial． The integral seismic performance of the two different construction model columns under the same working conditions was analyzed，the results show that the seismic behavior of the prefabricated column joints is equivalent to that of the steel pipe concrete and their bearing capacity is higher than the cast-in-place column in the same position． The seismic performance of the assembly column with locally encased steel pipe and integrity is better than the cast-in-place column，so it may replace the cast-in-place column in the highly seismic region． According to the damaging form and the force characteristics of the assembly column connection node， the formula of the normal section bearing capacity for the prefabricated column joints was given，which could be used in designing and checking the column joints of the actual assembly overall frame structure．