Concrete Composite Columns: Behavior and Design

Front Cover
Concrete Composite Columns
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Contents
Preface
1 Review and further analysis of concrete composite columns
	1.1 Introduction
	1.2 Steel-concrete composite columns
		1.2.1 Concrete-filled steel tube columns
		1.2.2 Concrete-filled special-shaped steel tube column
		1.2.3 Steel reinforced concrete-filled steel tube column
		1.2.4 Theoretical analysis of core concrete in steel tube
	1.3 FRP-confined concrete column
		1.3.1 The mechanical properties
		1.3.2 The stress–strain model for FRP-confined concrete
		1.3.3 The further study of FRP-confined concrete under insufficient confining effect
	1.4 FRP-steel-concrete composite column
		1.4.1 Hybrid double-skin tubular column
		1.4.2 FRP-confined concrete-filled steel tube column
		1.4.3 FRP-confined steel reinforced concrete column
		1.4.4 The further study of FRP-confined concrete-filled steel tube
	1.5 Discussion for the composite column
	1.6 Conclusions
	Acknowledgments
	References
2 Design-oriented constitutive model
	2.1 Introduction
	2.2 Lateral confining pressure around core concrete
		2.2.1 Confined concrete cylinder
		2.2.2 Concrete-filled square steel tube column
		2.2.3 Square hoops confined concrete column
		2.2.4 FRP confined concrete column
	2.3 Stress calculation and strain calculation
		2.3.1 Characteristic stress calculation of confined concrete
		2.3.2 Characteristic strain calculation of confined concrete
	2.4 Design-oriented constitutive models of confined concrete
		2.4.1 Steel tube or hoops confined concrete
		2.4.2 FRP confined concrete
	2.5 Conclusions
	Acknowledgments
	References
3 Failure criterion of concrete under multiaxial compression
	3.1 Introduction
	3.2 Stress condition of concrete under multiaxial compression
		3.2.1 Describe of multiaxial compressive experiment
		3.2.2 The stress condition of concrete under multiaxial compression
		3.2.3 The stress condition of concrete under multiaxial compression pressure
	3.3 The theoretical foundation of failure criterion models
		3.3.1 Development history of strength theory
		3.3.2 The Twin Shear Strength Theory
		3.3.3 The model establishment process
	3.4 Failure criterion models of concrete under multiaxial compressive pressure
		3.4.1 Five-parameter failure criterion A (principal shear stresses are as main influence factors)
			3.4.1.1 The ordinary solution of five-parameter failure criterion A
			3.4.1.2 Simplification solution of five-parameter failure criterion A
		3.4.2 Five-parameter failure criterion B (hydrostatic stress is main influence factor)
		3.4.3 Six-parameter failure criterion (both principal shear stress and hydrostatic stress are main influence factors)
			3.4.3.1 The boundary conditions with triaxial tensile stress
			3.4.3.2 The boundary conditions with triaxial compressive stress
	3.5 Failure criterion model validation
		3.5.1 Five-parameter failure criterion model A
		3.5.2 Five-parameter failure criterion model B
		3.5.3 Six-parameter failure criterion model
	3.6 Conclusions
	References
4 Analysis-oriented constitutive model
	4.1 Introduction
	4.2 Behavior of the confined concrete
	4.3 Stress model of the confined concrete
		4.3.1 Lateral confining pressures
		4.3.2 Existing stress models
		4.3.3 Improved failure criterion
		4.3.4 Stress models
		4.3.5 Value method of coefficients in the proposed model
		4.3.6 Verification of the stress model
	4.4 Strain analysis of the confined concrete by the energy method
		4.4.1 Existing strain models
		4.4.2 Strain state analysis by the energy-balance method
		4.4.3 Strain energy in the confined concrete column
			4.4.3.1 Axial strain energy
			4.4.3.2 Lateral strain energy
		4.4.4 Strain energy analysis of the confined concrete
			4.4.4.1 Strain energy analysis for the actively confined concrete
			4.4.4.2 Strain energy analysis for the FRP confined concrete
	4.5 Strain model for the confined concrete
		4.5.1 Strain model of the actively confined concrete
		4.5.2 Strain model of the FRP confined concrete
			4.5.2.1 Demarcation strain of the FRP confined concrete
			4.5.2.2 The discriminative confining state
			4.5.2.3 Ultimate strain of the FRP confined concrete
			4.5.2.4 Verification of the proposed models
				Verification of the actively confined concrete
				Verification of the FRP confined concrete
	4.6 Analysis-oriented constitutive model
		4.6.1 Analysis-oriented constitutive model of the FRP confined concrete under large confining effect
		4.6.2 Analysis-oriented constitutive model of the confined concrete with a softening stage
		4.6.3 Verification of the proposed models
	4.7 Conclusions
	Acknowledgments
	References
5 Steel frame confined concrete column
	5.1 Introduction
	5.2 Experimental program
		5.2.1 Specimen design
		5.2.2 Specimen preparation
		5.2.3 Basic properties of the material
		5.2.4 Test set-up and instrumentation
	5.3 Experimental results
		5.3.1 The failure process and failure mode
		5.3.2 The confining effect of the angle steel frame
		5.3.3 The load–strain curves of all specimens
		5.3.4 Analysis of the influence factors
			5.3.4.1 Strength of the unconfined concrete
			5.3.4.2 Angle steel size
			5.3.4.3 Assembly of the steel battens
			5.3.4.4 Thickness of the steel batten
			5.3.4.5 Layout of the spiral hoops
		5.3.5 Strains of the steel frame
			5.3.5.1 Axial strain of the angle steel
			5.3.5.2 Lateral strain of the steel batten
	5.4 The influence factor analysis by the finite element model
		5.4.1 Establishment of the finite element model
			5.4.1.1 Constitutive models
			5.4.1.2 Model element and model mesh
			5.4.1.3 Interaction, constraint, and boundary conditions
		5.4.2 The verification of the finite element model
			5.4.2.1 Verification of the load–displacement curve
			5.4.2.2 Verification of the failure modes
		5.4.3 Analysis of influence factors by the numerical simulation results
			5.4.3.1 Concrete strength grade
			5.4.3.2 Steel ratio of the angle steel
			5.4.3.3 Spacing between the steel battens
			5.4.3.4 Width of the steel batten
			5.4.3.5 Thickness of the steel batten
			5.4.3.6 The design of the steel batten
		5.4.4 Mechanism analysis of SCFs
			5.4.4.1 Elastic stage in the loading process
			5.4.4.2 Plastic stage in the loading process
			5.4.4.3 Failure stage in the loading process
	5.5 Design-oriented constitutive model for the steel frame confined concrete
		5.5.1 Confining mechanism of the steel frame
			5.5.1.1 Confining pressure provided by the angle steel
			5.5.1.2 Confining pressure provided by the steel batten
			5.5.1.3 Bearing capacity model of SFC
		5.5.2 The Design-oriented constitutive model
		5.5.3 Verification of constitutive model
	5.6 Conclusions
	Acknowledgments
	References
6 Confined recycled aggregate concrete column
	6.1 Introduction
	6.2 Simple mix design method of the recycled aggregate concrete
		6.2.1 Raw material properties
			6.2.1.1 Recycled coarse aggregate
			6.2.1.2 Other raw materials
		6.2.2 Orthogonal experiment
			6.2.2.1 Specimen design and fabrication
			6.2.2.2 Test process
			6.2.2.3 Analysis of test results
			6.2.2.4 Variance analysis
		6.2.3 Single-factor experiment
	6.3 Axial compressive test of confined RAC cylinder
		6.3.1 Experimental design
			6.3.1.1 Specimen design
			6.3.1.2 Preparation of specimens
			6.3.1.3 Mechanical properties of materials
			6.3.1.4 Test instrumentation and procedure
		6.3.2 Failure process and failure mode
		6.3.3 Load–displacement curve
		6.3.4 Load-axial strain curve
	6.4 Analysis of the confining effect
		6.4.1 Steel confined RAC
		6.4.2 GFRP confined RAC
		6.4.3 Double confined concrete
	6.5 Design-oriented constitutive model of the confined RAC
		6.5.1 Constitutive model of the steel tube confined concrete
			6.5.1.1 Stress and strain calculation equations
			6.5.1.2 Establishment of constitutive model
		6.5.2 Constitutive model of the GFRP confined RAC
			6.5.2.1 Stress and strain calculation equations
			6.5.2.2 Establishment of constitutive model
		6.5.3 Constitutive model of the GFRP confined RAC
	6.6 Conclusions
	Acknowledgments
	References
7 Hybrid double-skin tubular rectangular columns
	7.1 Introduction
	7.2 Experimental program
		7.2.1 Test specimens
		7.2.2 Preparation of specimens
		7.2.3 Material properties
		7.2.4 Test set-up and instrumentation
	7.3 Axial compressive test results
		7.3.1 The failure mode
		7.3.2 Typical axial compressive behavior
		7.3.3 Axial strain-hoop strain curves
		7.3.4 Parameter analysis
	7.4 Eccentric compressive test results
		7.4.1 Failure modes
		7.4.2 Axial load–displacement curve
		7.4.3 Axial load-lateral deflection curve
		7.4.4 Moment–curvature curves
		7.4.5 Strain of the steel section
		7.4.6 Strain of the FRP tube
	7.5 Conclusions
	Acknowledgments
	References
8 Seismic behavior of steel frame confined concrete column
	8.1 Introduction
	8.2 Experimental design
		8.2.1 Specimen design
		8.2.2 Specimen preparation
		8.2.3 Material properties
		8.2.4 Test set-up
		8.2.5 Test instrumentation
	8.3 Failure process and failure mode
		8.3.1 Failure process
		8.3.2 Analysis of failure modes
	8.4 The seismic experiment results
		8.4.1 Hysteretic curve
		8.4.2 Skeleton curve
		8.4.3 Deformation capacity
		8.4.4 Strength reduction
		8.4.5 Stiffness reduction
		8.4.6 Energy consumption capacity
		8.4.7 Stress state of angle steel and steel batten
	8.5 Conclusions
	Acknowledgments
	References
9 Design method of steel frame confined concrete column
	9.1 Introduction
	9.2 Finite element model establishment
		9.2.1 Constitutive models of materials
		9.2.2 Element selection and section division
		9.2.3 Boundary conditions and loading steps
		9.2.4 Verification of the proposed finite element model
	9.3 Finite element model analysis
		9.3.1 Strain state of the angle steel
		9.3.2 Stress state of core concrete
		9.3.3 Section moment-curvature relationship
		9.3.4 Equivalent plastic hinge length
		9.3.5 Parameter analysis
			9.3.5.1 Axial compression ratio
			9.3.5.2 Angle steel size
			9.3.5.3 Arrangement of the steel battens
	9.4 Section analysis model
		9.4.1 Constitutive models of materials
		9.4.2 Section analysis model of axial force-moment-curvature (N-M-φ)
			9.4.2.1 Model establishment
			9.4.2.2 Model verification
			9.4.2.3 Parameter analysis of moment-curvature relationship
			9.4.2.4 Parameter analysis of axial force-moment relationship
	9.5 Calculation method of the axial force-moment-curvature (N–M–φ)
		9.5.1 Calculation method of the axial force-moment curve
		9.5.2 Skeleton model of the section moment-curvature curves
		9.5.3 Section moment-curvature hysteresis model
	9.6 Damage evaluation method of SFCs
		9.6.1 Analysis of yield section curvature
		9.6.2 Analysis of the ultimate section curvature
		9.6.3 Calculation method of section curvature ductility coefficient
		9.6.4 Damage index model
	9.7 Conclusions
	Acknowledgments
	References
10 Engineering application of steel frame confined concrete column
	10.1 Introduction of the static elastic-plastic analysis
		10.1.1 Basic assumptions of static elastic-plastic analysis
		10.1.2 Specific steps of the pushover analysis
		10.1.3 Lateral loading mode of the pushover analysis method
		10.1.4 Target displacement
	10.2 Pushover analysis of the large thermal power plant
		10.2.1 Project overview
		10.2.2 Model establishment
		10.2.3 Calculation parameters
	10.3 Analysis and discussion of calculation results
		10.3.1 Static elastic-plastic curve
		10.3.2 Base shear-top displacement curve
		10.3.3 Layer shear force
		10.3.4 Interlayer displacement angle
		10.3.5 Cooperation relationship in the frame-bent structure
		10.3.6 Structural plastic hinge
	10.4 Introduction of the performance-based seismic design method of the frame-bent structure of the large thermal power plant
		10.4.1 Seismic fortification target
		10.4.2 Basic content of the performance-based design method
		10.4.3 Direct displacement-based method
	10.5 Member design method of the large thermal power plant
		10.5.1 Shear wall design
		10.5.2 Steel frame confined concrete column design
	10.6 Performance level and performance target of SFC frame-bent structure in the large thermal power plant
		10.6.1 Division of the structural performance level
		10.6.2 Quantification of the structural performance objectives
	10.7 Displacement-based seismic design of the SFC frame-bent structure in the large thermal power plant
		10.7.1 Target displacement mode
		10.7.2 Equivalent parameters of the equivalent single-freedom system
		10.7.3 Displacement response spectrum
		10.7.4 Displacement-based seismic design steps
	10.8 Analysis of practical examples
	10.9 Seismic design based on the “normal use” condition
	10.10 Seismic design in “normal use” after correction
	10.11 Seismic design based on the “basic use” condition
	10.12 Seismic design based on the “life safety” condition
	10.13 Seismic design based on the “near collapse” condition
	10.14 Conclusions
	Acknowledgments
	References
Index
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