410
12 Experimental Study on the Residual Seismic Resistance of UHPCC …
Crack
Front
Spalling
Side
50
Front
Crack
Spalling
Side
50
(a)
(b)
Front
Crack
Spalling
Side
60
Front
250
Crack
Side
(c)
(d)
Front
250
Crack
Crack
175
Side
Front
250
Crack
Side
(e)
(f)
Fig. 12.13 Failure pattern of specimens a II-1 b II-2 c C-11 d C-12 e C-13 f C-14 (unit mm),
reprinted from Wang et al. (2020b), copyright 2020, with permission from Elsevier
(i) II-1 specimen was an intact column, which was tested as the control column.
At early stage of loading, the steel tube was in the elastic state, and nearly no
obvious cracks appeared on the specimen. With the lateral displacement
increasing up to 140 mm, the steel tube exhibited local buckling at the bottom
of the column. After three loading cycles at the same lateral displacement
level, the plastic hinge further developed at the height of 50 mm from the top
surface of the column base. As the lateral displacement increased, the degree
of buckling enhanced intensively along the loading direction. It is also found
that under the repeated tension and compression, an evident sign of cracking