Ultimate moment capacity of foamed and lightweight aggregate concrete-filled steel tubes

The post-fire behavior of a set of self-stress lightweight aggregate concrete filled steel tubular short columns (noted as SSLC-SSC) after exposure to fire was experimentally studied. Effect of the maximum value of fire response temperatures of the tubes and their geometric parameters on the strength and the other mechanical property of the specimens were especially discussed. The experimental results show that the specimens of SSLC-SSC have higher post-fire bearing capacity and better plastic deformation, there was no obvious descent segment in post-fire load-displacement curves of the most specimens subjected to fire load. It was concluded that the maximum response temperature of specimens has great effect on the post-fire bearing capacity of self-stress concrete-filled steel tubes subjected to fire load, and the value of self-stress corresponding to 10% of dosage of expansive agent has the greatest effect on post-fire bearing capacity of specimens of SSLC-SSC.

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Study of Post-Fire Axial Compressive Behavior of Self-Stress Ceramsite Concrete Filled Steel Tubular Short Columns

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.790.185 ◽

2013 ◽

Vol 790 ◽

pp. 185-188

Author(s):

Jian Qi Lu ◽

Hai Lun Tong ◽

Jin Can Xu ◽

Xin Tang Wang

Keyword(s):

Longitudinal Strain ◽

Circumferential Strain ◽

Local Buckling ◽

Lightweight Aggregate ◽

Lightweight Aggregate Concrete ◽

Compressive Behavior ◽

Steel Tubes ◽

Aggregate Concrete ◽

Short Columns ◽

Concrete Filled Steel Tubes

The post-fire axial compressive behavior of a set of self-stress lightweight aggregate concrete filled steel tubes (noted as SSLC-ST) after exposure to fire was studied. Effect of the fire temperatures of the specimens and some parameters on the axial compressive behavior of the specimens was especially discussed. The results show that the initial circumferential strain of surface of the steel tubes is much larger than the longitudinal strain of the steel tubes, and the specimens of SSLC-ST have higher post-fire axial compression bearing capacity and better plastic deformation. It was concluded that the local buckling and overall failure of the specimens take place in succession while the specimens are axially loaded, and there are a lot of slip lines with angle of 45oon surface of the steel tubes.

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Pure Bending behavior of Lightweight Aggregate Concrete Filled Circular Steel Tubes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.374-377.2239 ◽

2011 ◽

Vol 374-377 ◽

pp. 2239-2244

Author(s):

Fa Xing Ding ◽

Ya Ting Luo ◽

Xiao Yong Ying ◽

Zhao Hui Lu

Keyword(s):

Lightweight Aggregate ◽

Fortran Program ◽

Lightweight Aggregate Concrete ◽

Pure Bending ◽

Steel Tubes ◽

Aggregate Concrete ◽

Composite Section ◽

The Moment ◽

Relationship Of ◽

Concrete Filled Steel Tubes

Based on appropriate numerical constitutive model of lightweight aggregate concrete filled steel tubes (LCFST), layered method was adopted to predict the complete moment-curvature curves of LCFST composite section subjected to pure bending. A FORTRAN program for the moment-curvature curves was developed. Applying the layered method, the influences of the significant parameters, such as steel ratio, yield strength of steel and strength of lightweight aggregate concrete on the moment-curvature curves of the composite section subjected to pure bending were discussed. The practical composite flexural stiffness, ultimate moment and practical moment- curvature relationship of LCFST composite section were presented. The predicted results of both layered method and practical moment-curvature relationships of LCFST composite section are in good agreement with the test results from reference. Compared with the layered method, practical calculate method could remove the step of composite section layered and improve the calculation speed while achieving similar results.

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Experimental Study of Post-Fire Behavior of Steel Fiber Reinforced Ceramsite Concrete Filled Steel Tubes

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.204-208.3401 ◽

2012 ◽

Vol 204-208 ◽

pp. 3401-3404

Author(s):

Jin Yi Zhang ◽

Xin Tang Wang ◽

Ping Xin Sun ◽

Hong Liang Sun

Keyword(s):

Steel Fiber ◽

Mechanical Performance ◽

Fire Behavior ◽

Lightweight Aggregate ◽

Lightweight Aggregate Concrete ◽

Fire Performance ◽

Fiber Reinforced ◽

Furnace Temperature ◽

Steel Tubes ◽

Concrete Filled Steel Tubes

The axial compressive mechanical behavior of steel fiber reinforced ceramsite concrete filled steel tubes (noted as SFR-CCST) after exposure to fire are experimentally studied. Effect of furnace temperature, dosage of steel fiber in specimens on the post-fire mechanical performance of the specimens after exposure to fire was especially discussed. The results show that all the specimens of SFR-CCST have higher post-fire bearing capacity and better plastic deformation, and there was no obvious descending segment in the load-strain curves of the most specimens after exposure to fire. It was concluded that the furnace temperature applied to the specimens and dosage of steel fiber in the specimens of SFR-CCST has some effect on the post-fire mechanical performance of the ceramsite concrete-filled steel tubes after exposure to fire, and the dosage of steel fiber of 0.5% has the most effect on the post-fire performance of lightweight aggregate concrete filled steel tubes after exposure to fire.

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