en Structure-Concrete Structure- Concrete Research Paper Research Paper <p>To study seismic performance of concrete-encased composite columns with T-shaped steel cross-section, twelve half-scale columns were tested under quasi-stastic cyclic loading. The result indicates that concrete-encased composite columns with T-shaped steel section possess good seismic performance. The failure modes include bending failure, shear-bond failure, shear compression failure and shear-composition failure. Unsymmetrical phenomenon of positive and negative hysteresis loop was shown evidently. Span ratio has a great influence on failure mode. The ductility performance decreases with increasing of axial compression level. As stirrup ratio increases, ductility and bearing capacity of columns are improved<a name="OLE_LINK6"> greatly, </a>and energy dissipation capacity after yielding is enhanced. Cross tie can enhance ultimate bearing capacity, and lower strength attenuation and stiffness degradation on the later loading stage</p> Concrete-encased composite column, Unsymmetrical, Seismic behavior, Experimental study 455 467 http://ijce.iust.ac.ir/browse.php?a_code=A-10-2563-2&slc_lang=en&sid=1 L. Zeng zenglei@yangtzeu.edu.cn 1800319475328460010484 1800319475328460010484 Yes Yangtze University Q. Zhou zhouqin126@163.com 1800319475328460010485 1800319475328460010485 No Yangtze University Ch. Xu cx_xu@sina.com 1800319475328460010486 1800319475328460010486 No Yangtze University Y. Wu wuyuan9950@163.com 1800319475328460010487 1800319475328460010487 No Yangtze University X. Tu 1800319475328460010488 1800319475328460010488 No Yangtze University