Fire Resistance of Circular Steel Tube Columns Infilled With Reinforced Concrete

In this study, an inelastic biaxial bending experiment in which a horizontal force is loaded in a direction at a certain angle to the principal axis of the section was carried out for H-shaped steel beam-columns each with a relatively small slenderness ratio having an inelastic energy absorption capacity. As the result of studies on the elasto-plastic behavior as well as on the analysis results, it was made clear that the maximum strength ratio (the ratio of the maximum moment to the full plastic moment), the ductility factor and the energy absorption capacity decrease with the change in the loading angle from 0 • (strong axis bending load) to 90 • (weak axis bending load).

Inelasatic Behavior of H-Shaped Steel Beam-Columns Subjected to Two-Dimensional Horizontal Monotonic Load

Yamazaki¹,

Minami²,

Takahama³

2008

Behavior of Centrically Loaded Box-Section Steel Columns Until Complete Collapse

Yamazaki¹,

Minami²,

Haneda³

2008

The behavior of centrically loaded box-section steel columns until they have reached a stage of complete collapse was studied by carrying out a series of experiments and analyses. The results obtained from this study can be summarized as follows: (1) The behavior after the yield of the steel columns can be divided into two types; the flexural buckling type in which the progress of lateral deflection results in collapse and the local buckling type in which the local buckling occurring successively along member-length results in collapse. A conditional expression of members for the discrimination of these two types of behavior was derived. (2) A method for analyzing the behavior of flexural buckling type members was developed and the validity of this analysis method was confirmed in comparison with the experiment results. (3) A model to estimate the load-deflection relationship of local buckling type members was derived.

Study on Fire Resistance of Concrete Filled Tubular Columns

Kikuta¹,

Suzuki²

2011

This study aims to evaluate theoretically the fire resistance capacities of concrete filled tubular columns subjected to fire and axial compression. A strength analysis has been made in which all strains found in heated concrete including stress strain, thermal expansion and transient strain are taken into account. Since, among others, transient strain plays a key role on the behavior of heated columns, a new theoretical procedure to treat this strain is postulated and an explicit closed form solution is derived for the ultimate column strength. With comparison between the solutions and test data, it is found that the strength of a heated column is decreased significantly below its full plastic strength due to transient strain, if the column is made of higher strength concrete, is subjected to larger axial force or if it is of a larger cross section. For all the cases, the solutions are found in good agreement with the test results.