When walls and columns are demolished on demolition sites in Japan, they are pulled down by heavy machinery or wire rope after the lower part of walls and columns are cut to weaken their structural integrity before pull-down. However, when the cut is too deep, the walls and columns can collapse and crush workers. It needs to examine the relationship between the cutting of the lower part of wall and column and the stability of the wall and column for a reduced number of accidents. In this paper, it was focused on the column as basic unit of walls and columns. This study carries out the fall-down test of columns with the lower part cutting to review and ensure safe cutting of walls and columns. From the results, the model without concrete on the compression side of the fall-down was lower strength. The model with one row of reinforcement was low strength as felled down by the weight of wire rope. It was proposed that when the lower part of columns is cut on demolition sites, the workers should leave two rows of main reinforcement and leave concrete around the second row of main reinforcement.
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