Two ungrouted post-tensioned, precast concrete-filled tube (CFT) segmental bridge columns were tested under lateral cyclic loading to evaluate the seismic performance of the column details. The specimens included a load stub, four equal-height circular CFT segments, and a footing. Strands were placed through the column and post-tensioned to provide a precompression of the column against the footing. One specimen also contained energy-dissipating devices at the base to increase the hysteretic energy. The test results showed that (1) both specimens could develop the maximum flexural strength at the design drift and achieve 6% drift with small strength degradation and residual displacement, (2) the proposed energy-dissipating device could increase energy dissipation in the hysteresis loops, and (3) the CFT segmental columns rotated not only about the base but also about the interface above the bottom segment. This study proposed and verified a method to estimate the experimental flexural displacement using two plastic hinges in the segmental column. Copyright © 2005 John Wiley & Sons, Ltd.

https://ir.nctu.edu.tw:443/bitstream/11536/12666/1/000234702300002.pdf

Cyclic tests of post‐tensioned precast CFT segmental bridge columns with unbonded strands

Experimental study on seismic behavior of high-strength concrete filled double-steel-plate composite walls

Nonlinear analysis of circular concrete-filled steel tubular short columns under eccentric loading

https://hal.archives-ouvertes.fr/hal-00351799/document

An elastic plastic damage formulation for concrete: Application to elementary tests and comparison with an isotropic damage model

Stress–strain model for concrete in FRP-confined steel tubular columns

Uniaxial stress–strain relationship of concrete confined by various shaped steel tubes

Concrete-filled steel columns have been widely used in civil and architectural constructions throughout the world in recent years. This study is concerned with the cyclic elastoplastic analysis and capacity prediction of concrete-filled steel columns having thick- and thin-walled stiffened box-shaped sections. An analytical procedure for determining the ultimate state of the concrete-filled steel column is proposed based on the fiber analysis technique. Strength and ductility predictions are made by means of a new failure criterion. This is proposed based on the average failure strain of concrete and steel at critical regions. A recently developed monotonic stress–strain relation for confined concrete is modified so that it can be used in the analysis of thin- or thick-walled section columns with stiffeners. A simple cyclic rule is introduced into this model in order to be used in cyclic analysis. Material non-linearity of steel is represented by the modified two surface model developed at Nagoya University. The predictions are then compared with the existing experimental results and found to exhibit satisfactory agreement. Both small- and large-scaled columns are considered in the comparisons. Copyright © 2001 John Wiley & Sons, Ltd.

Cyclic analysis and capacity prediction of concrete-filled steel box columns

The purpose of this experimental work is to investigate the seismic resistance characteristics of rectangular-shaped steel bridge piers commonly found in rigid frames, concerning the cross-sectional aspect ratios. To this end, seven specimens were tested under cyclic lateral loads. Six of them were under constant compressive axial load and one was under variable axial load. At first, the effects of web to flange aspect ratio ( W∕F ratio) on the differences between actual and estimated yield displacements, yield loads and flexural stiffness were examined. W∕F ratio of around 2.0 was found to offer minimum difference between those values. Secondly, the effects of W∕F ratio on ultimate strength, ductility, and energy dissipation capacity were determined. The highest strength was observed in columns with a W∕F ratio of about 2.0 while the highest ductility and cumulative energy dissipation capacity were in those with a W∕F ratio of around 1.60. Also, the effect of varying axial load on the strength was examin...

Seismic performance of rectangular-shaped steel piers under cyclic loading

A seismic design procedure for partially concrete-filled box-shaped steel columns is presented in this paper. To determine the ultimate state of such columns, concrete and steel segments are modelled using beam-column elements and a pushover analysis procedure is adopted. This is done by means of a new failure criterion based on the average strain of concrete and steel at critical regions. The proposed procedure is applicable to columns having thin- and thick-walled sections, which are longitudinally stiffened or not. An uniaxial constitutive relation recently developed is employed for concrete filled in the thick-walled unstiffened section columns. Modifications are introduced to this model for other types of columns. Subsequently, the strength and ductility predictions obtained using the present and previous procedures are compared with the corresponding experimental results. Comparisons show that the present procedure yields better predictions. It is revealed that the inclusion of the confinement effec...

K.A.S. Susantha

Papers

Uniaxial stress–strain relationship of concrete confined by various shaped steel tubes

Cyclic analysis and capacity prediction of concrete-filled steel box columns

Seismic performance of rectangular-shaped steel piers under cyclic loading

A capacity prediction procedure for concrete-filled steel columns

Seismic demand predictions of concrete-filled steel box columns