Investigation the behavior of LWAC encased steel columns
after exposure to elevated temperature
Noor Al-Huda Al-Talqani1 | Haitham Al-Thairy1,2
1Civil Engineering Department, College of
Engineering, University of Al-Qadisiyah,
Al Diwaniyah, Iraq
2College of Engineering, University of
Warith Al-Anbiyaa, Karbala, Iraq
Correspondence
Haitham Al-Thairy, Civil Engineering
Department, College of Engineering,
University of Al-Qadisiyah, Al Diwaniyah,
Iraq.
Email: haitham.althairy@qu.edu.iq
Abstract
This paper presents experimental and numerical investigations on the behavior
of eccentrically loaded lightweight aggregate concrete encased steel (LWACES)
columns after exposing to elevated temperatures. Sixteen concrete encased steel
(CES) columns were considered in the study, 12 of which were exposed to elevated
temperature then eccentrically loaded up to failure at different eccentricity
ratios. The effect of temperature on the load–displacement relationships, failure
load, and failure modes of the concrete encased steel (CES) columns was monitored
and evaluated. Experimental results have shown that as the temperature
increases, the load bearing capacity of the CES columns decreased. It has also
been showed that, at high temperature, the normal-weight concrete encased
steel (NWCES) columns experienced larger degradation of the load bearing
capacity compared to that of LWACES columns. Also, this study presents a
numerical simulation of the behavior of LWACES columns at elevated temperatures
with eccentric compressive load. The numerical model was implemented
in conducting parametric study to understand the effect of temperature distribution,
concrete cover, eccentricity ratio, and high temperature levels on the
behavior of the thermally exposed (CES) columns. Numerical results have
revealed that, at temperature value of 500C, the ultimate capacity of LWACES
with eccentricity ratios of 0.75, and 1 has decreased by 17%, and 23%, respectively,
compared to that of the column with eccentricity ratio of 0.5.