Experimental Study on Progressive Collapse Performance of Frame with Specially Shaped Columns Subjected to Middle Column Removal

Figure 2

Section dimension and reinforcement details of beam and columns. (Note: R and T stand for steel bars with nominal yield strengths of 300 MPa and 400 MPa, resp.; the number following R or T represents the nominal diameter of a bar. @ stands for stirrup space. There is a decrease in spacing of stirrup by half of the near beam-column joint point according to Chinese seismic code.)

(a) Z1 column

(b) Z2 column

(c) Z3 column

(d) Beam