DESIGN OF BUILDINGS TO RESIST PROGRESSIVE COLLAPSE
Record of Changes - 4_023_030002
FOREWORD - 4_023_030003
CONTENTS - 4_023_030004
CONTENTS-continued - 4_023_030005
CONTENTS-continued - 4_023_030006
CONTENTS-continued - 4_023_030007
CONTENTS-continued - 4_023_030008
CONTENTS-continued - 4_023_030009
FIGURES - 4_023_030010
FIGURES-continued - 4_023_030011
TABLES - 4_023_030013
CHAPTER 1. INTRODUCTION - 4_023_030014
Design Approaches
Existing Design Guidelines
SUMMARY OF PROGRESSIVE COLLAPSE DESIGN PROCEDURE
DoD Minimum Antiterrorism Standards for Buildings - 4_023_030018
Security Engineering Support Manuals-continued - 4_023_030019
CHAPTER 2. PROGRESSIVE COLLAPSE DESIGN REQUIREMENTS FOR NEW AND EXISTING CONSTRUCTION
Figure 2-1 Design Process for VLLOP in New and Existing Construction
Figure 2-2 Design Process for LLOP in New and Existing Construction
Medium and High Level of Protection Design Requirement
Additional Ductility Requirements for MLOP and HLOP-continued
Figure 2-3 Design Process for MLOP and HLOP in New and Existing Construction
COMMON DESIGN REQUIREMENTS
CHAPTER 3. DESIGN STRATEGIES
Required Tie Strength
Figure 3-1 Schematic of Tie Forces in a Frame Structure
ALTERNATE PATH METHOD - 4_023_030030
Load and Resistance Factor Design for Alternate Path Method
External Column Removal
Figure 3-2 Location of External Column Removal for MLOP and HLOP Structures
MLOP and HLOP Load-Bearing Wall Structures
Internal Load-Bearing Walls
Factored Loads for Alternate Path Method - 4_023_030036
Material Properties
Figure 3-7. Examples of Linear and Nonlinear Static Load Locations for External and Internal Column Removal
Figure 3-8. Examples of Linear and Nonlinear Static Load Locations for External and Internal Load-Bearing Wall Removal
Damage Limits for the Structure
Figure 3-9 Inserting Hinge and Moments into Linear Static Alternate Path Model
Table 3-1 Acceptability Criteria for Elements and Connections and Subsequent Action for AP Model
Combined Axial and Flexure
Figure 3-11 Sidesway and Member End Rotations (θ) for Frames
Linear Static Analysis Procedure
Nonlinear Static Analysis Procedure
Nonlinear Dynamic Analysis Procedure
Nonlinear Dynamic Analysis Procedure-continued
CHAPTER 4. REINFORCED CONCRETE DESIGN REQUIREMENTS
Internal Ties - 4_023_030050
Peripheral Ties - 4_023_030051
Horizontal Ties to External Columns and Walls - 4_023_030052
Elements with Deficient Vertical Design Tie Strengths
ALTERNATE PATH METHOD FOR REINFORCED CONCRETE
Combined Axial and Bending Resistance of Reinforced Concrete
ADDITIONAL DUCTILITY REQUIREMENTS - 4_023_030056
Table 4-4 Deformation Limits for Reinforced Concrete
CHAPTER 5. STRUCTURAL STEEL DESIGN REQUIREMENTS
STEEL TIE FORCE REQUIREMENTS
Figure 5-1 Example of Tying the Columns of a Steel Building
Internal Ties - 4_023_030061
ALTERNATE PATH METHOD FOR STRUCTURAL STEEL
Nominal strengths
Flexural Resistance of Structural Steel
Combined Axial and Bending Resistance of Structural Steel
ADDITIONAL DUCTILITY REQUIREMENTS - 4_023_030066
Table 5-3 Deformation Limits for Structural Steel
CHAPTER 6. MASONRY DESIGN REQUIREMENTS
Internal Ties - 4_023_030069
Horizontal Ties to External Columns and Walls - 4_023_030070
Vertical Ties - 4_023_030071
Load-Bearing Walls and Columns with Deficient Vertical Tie Forces
Table 6-2 Removal of Deficient Masonry Vertical Tie Elements
ALTERNATE PATH METHOD FOR MASONRY
Axial Resistance of Masonry
ADDITIONAL DUCTILITY REQUIREMENTS - 4_023_030076
CHAPTER 7. WOOD DESIGN REQUIREMENTS
Strength Reduction Factor Φ for Wood Tie Forces
Horizontal Ties to External Walls and Columns - 4_023_030079
Vertical Ties - 4_023_030080
Load-bearing Elements with Deficient Vertical Tie Forces
ALTERNATE PATH METHOD FOR WOOD
ADDITIONAL DUCTILITY REQUIREMENTS - 4_023_030083
Table 7-3 Deformation Limits for Wood
CHAPTER 8. COLD-FORMED STEEL DESIGN REQUIREMENTS
Internal Ties - 4_023_030086
Horizontal Ties to External Walls and Columns - 4_023_030087
Vertical Ties - 4_023_030088
ALTERNATE PATH METHOD FOR COLD-FORMED STEEL
Flexural Resistance of Cold-Formed Steel
Combined Axial and Bending Resistance of Cold-Formed Steel
ADDITIONAL DUCTILITY REQUIREMENTS - 4_023_030092
APPENDIX A. REFERENCES - 4_023_030093
APPENDIX A. REFERENCES-continued - 4_023_030094
APPENDIX A. REFERENCES-continued - 4_023_030095
APPENDIX A. REFERENCES-continued - 4_023_030096
APPENDIX B. COMMENTARY
TIE FORCES
Reinforced Concrete Tie Forces
Figure B-1 Calculation of Upper Bound on the Basic Strength
Figure B-2 Determination of lr for Frame Construction
Peripheral Ties - 4_023_030102
Figure B-5 Peripheral Tie Detail for Corner Columns
Figure B-6 Lateral Support For Stiffened Sections
Steel Tie Forces
Figure B-8 Lateral Support For Intersecting or Return Walls
Figure B-9 Lateral Support For Piers or Stiffened Sections
Wood Frame Tie Forces
ALTERNATE PATH METHOD - 4_023_030109
Factored Loads for Alternate Path Method - 4_023_030110
Plastic Hinge Considerations for AP Modeling of Steel Structures
Nonlinear Analyses of Beam-Columns
Deformation Limits
ADDITIONAL DUCTILITY REQUIREMENTS - 4_023_030114
Table B-1 Steel Moment Frame Connection Types
Figure B-11 Fully Restrained Connections
Figure B-12 Partially Restrained Connections
Figure B-13 Weak Axis Connections
APPENDIX C. WORKED REINFORCED CONCRETE FRAME EXAMPLE
Loading Assumptions - 4_023_030120
Figure C-1 Reinforced Concrete Building Plan
Member Sizes
ALTERNATE PATH SETUP
Figure C-3 Plan of Removed Column
Progressive Collapse Load Combination - 4_023_030125
ALTERNATE PATH ANALYSIS
Define and Assign Hinge Properties
Define Nonlinear Analysis Cases - 4_023_030128
Progression of Hinge Formations
Figure C-9 Hinges and Deformed Shape (isometric view)
Figure C-10 Hinges and Deformed Shape (x-x single bay)
Table C-4 Properties of Redesigned Members
Shear Capacity and Other Capacity Checks - 4_023_030133
APPENDIX D. WORKED STRUCTURAL STEEL FRAME EXAMPLE TIE FORCE AND NONLINEAR ALTERNATE PATH ANALYSIS
Loading Assumptions - 4_023_030135
Figure D-2 Steel Building Elevation
TIE FORCE CHECK
Table D-2 Required Tie Forces
ALTERNATE LOAD PATH
Figure D-4 Plan of Removed Column
Progressive Collapse Load Combination - 4_023_030141
ALTERNATE LOAD PATH ANALYSIS
Figure D-7 Completed Nonlinear Static Model
Define Nonlinear Analysis Cases - 4_023_030144
Run Analysis
Figure D-10 Hinges and Deformed Shape (isometric view)
Table D-4 Beam and Column Sections for Final Design
Shear Capacity and Other Capacity Checks - 4_023_030148
APPENDIX E. MASONRY CONNECTIONS FOR PROGRESSIVE COLLAPSE DESIGN
Figure E-3. Wood Rafter at Exterior Block Wall
Figure E-6. Precast Concrete Slab Trough Brick Cavity Interior Wall
Figure E-8. Precast Floor Plans at Exterior Block Wall
APPENDIX F. GUIDANCE FOR PROGRESSIVE COLLAPSE DESIGN IN WOOD FRAME STRUCTURES
Figure F-1 Depiction of Barracks Buildings Used in Tie Force Example
Table F-1 Required Tie Forces for Barracks Building
Table F-2 Calculations for Tie Force Wood Member and Connection Design
Table F-2 Calculations for Tie Force Wood Member and Connection Design-continued
Figure F-3 Schematic of Internal and Horizontal Ties
Figure F-5 Schematic of Peripheral and Horizontal Ties; E-W Detail
ALTERNATE PATH METHOD FOR WOOD FRAME CONSTRUCTION
Figure F-7 Illustrations of Rim Beam Use in Wood Frame Construction
Figure F-9 Potential Redistribution of Floor Loads
Example Building
Case 1 Removal of Column in N-S Exterior Wall
Table F-6 Acceptability Criteria Check for Wall Studs
Figure F-10 Cross Section of North-South Exterior Wall
Case 2 Removal of Interior Column
Table F-8 Acceptability Criteria Check for Columns
Figure F-11 Cellular Layout
Figure F-12 Notional Exterior Load Bearing Wall Removal
Summary of Alternate Path Example
APPENDIX G. 2003 INTERNATIONAL BUILDING CODE MODIFICATIONS FOR CONSTRUCTION OF BUILDINGS TO RESIST PROGRESSIVE COLLAPSE
QUALITY ASSURANCE FOR PROGRESSIVE COLLAPSE REQUIREMENTS
[Addition] Contractor responsibility
STRUCTURAL OBSERVATIONS - 4_023_030175
STRUCTURAL OBSERVATIONS - 4_023_030176
4_023_03
Record of Changes - 4_023_030002
FOREWORD - 4_023_030003
CONTENTS - 4_023_030004
CONTENTS-continued - 4_023_030005
CONTENTS-continued - 4_023_030006
CONTENTS-continued - 4_023_030007
CONTENTS-continued - 4_023_030008
CONTENTS-continued - 4_023_030009
FIGURES - 4_023_030010
FIGURES-continued - 4_023_030011
TABLES - 4_023_030013
CHAPTER 1. INTRODUCTION - 4_023_030014
Design Approaches
Existing Design Guidelines
SUMMARY OF PROGRESSIVE COLLAPSE DESIGN PROCEDURE
DoD Minimum Antiterrorism Standards for Buildings - 4_023_030018
Security Engineering Support Manuals-continued - 4_023_030019
CHAPTER 2. PROGRESSIVE COLLAPSE DESIGN REQUIREMENTS FOR NEW AND EXISTING CONSTRUCTION
Figure 2-1 Design Process for VLLOP in New and Existing Construction
Figure 2-2 Design Process for LLOP in New and Existing Construction
Medium and High Level of Protection Design Requirement
Additional Ductility Requirements for MLOP and HLOP-continued
Figure 2-3 Design Process for MLOP and HLOP in New and Existing Construction
COMMON DESIGN REQUIREMENTS
CHAPTER 3. DESIGN STRATEGIES
Required Tie Strength
Figure 3-1 Schematic of Tie Forces in a Frame Structure
ALTERNATE PATH METHOD - 4_023_030030
Load and Resistance Factor Design for Alternate Path Method
External Column Removal
Figure 3-2 Location of External Column Removal for MLOP and HLOP Structures
MLOP and HLOP Load-Bearing Wall Structures
Internal Load-Bearing Walls
Factored Loads for Alternate Path Method - 4_023_030036
Material Properties
Figure 3-7. Examples of Linear and Nonlinear Static Load Locations for External and Internal Column Removal
Figure 3-8. Examples of Linear and Nonlinear Static Load Locations for External and Internal Load-Bearing Wall Removal
Damage Limits for the Structure
Figure 3-9 Inserting Hinge and Moments into Linear Static Alternate Path Model
Table 3-1 Acceptability Criteria for Elements and Connections and Subsequent Action for AP Model
Combined Axial and Flexure
Figure 3-11 Sidesway and Member End Rotations (θ) for Frames
Linear Static Analysis Procedure
Nonlinear Static Analysis Procedure
Nonlinear Dynamic Analysis Procedure
Nonlinear Dynamic Analysis Procedure-continued
CHAPTER 4. REINFORCED CONCRETE DESIGN REQUIREMENTS
Internal Ties - 4_023_030050
Peripheral Ties - 4_023_030051
Horizontal Ties to External Columns and Walls - 4_023_030052
Elements with Deficient Vertical Design Tie Strengths
ALTERNATE PATH METHOD FOR REINFORCED CONCRETE
Combined Axial and Bending Resistance of Reinforced Concrete
ADDITIONAL DUCTILITY REQUIREMENTS - 4_023_030056
Table 4-4 Deformation Limits for Reinforced Concrete
CHAPTER 5. STRUCTURAL STEEL DESIGN REQUIREMENTS
STEEL TIE FORCE REQUIREMENTS
Figure 5-1 Example of Tying the Columns of a Steel Building
Internal Ties - 4_023_030061
ALTERNATE PATH METHOD FOR STRUCTURAL STEEL
Nominal strengths
Flexural Resistance of Structural Steel
Combined Axial and Bending Resistance of Structural Steel
ADDITIONAL DUCTILITY REQUIREMENTS - 4_023_030066
Table 5-3 Deformation Limits for Structural Steel
CHAPTER 6. MASONRY DESIGN REQUIREMENTS
Internal Ties - 4_023_030069
Horizontal Ties to External Columns and Walls - 4_023_030070
Vertical Ties - 4_023_030071
Load-Bearing Walls and Columns with Deficient Vertical Tie Forces
Table 6-2 Removal of Deficient Masonry Vertical Tie Elements
ALTERNATE PATH METHOD FOR MASONRY
Axial Resistance of Masonry
ADDITIONAL DUCTILITY REQUIREMENTS - 4_023_030076
CHAPTER 7. WOOD DESIGN REQUIREMENTS
Strength Reduction Factor Φ for Wood Tie Forces
Horizontal Ties to External Walls and Columns - 4_023_030079
Vertical Ties - 4_023_030080
Load-bearing Elements with Deficient Vertical Tie Forces
ALTERNATE PATH METHOD FOR WOOD
ADDITIONAL DUCTILITY REQUIREMENTS - 4_023_030083
Table 7-3 Deformation Limits for Wood
CHAPTER 8. COLD-FORMED STEEL DESIGN REQUIREMENTS
Internal Ties - 4_023_030086
Horizontal Ties to External Walls and Columns - 4_023_030087
Vertical Ties - 4_023_030088
ALTERNATE PATH METHOD FOR COLD-FORMED STEEL
Flexural Resistance of Cold-Formed Steel
Combined Axial and Bending Resistance of Cold-Formed Steel
ADDITIONAL DUCTILITY REQUIREMENTS - 4_023_030092
APPENDIX A. REFERENCES - 4_023_030093
APPENDIX A. REFERENCES-continued - 4_023_030094
APPENDIX A. REFERENCES-continued - 4_023_030095
APPENDIX A. REFERENCES-continued - 4_023_030096
APPENDIX B. COMMENTARY
TIE FORCES
Reinforced Concrete Tie Forces
Figure B-1 Calculation of Upper Bound on the Basic Strength
Figure B-2 Determination of lr for Frame Construction
Peripheral Ties - 4_023_030102
Figure B-5 Peripheral Tie Detail for Corner Columns
Figure B-6 Lateral Support For Stiffened Sections
Steel Tie Forces
Figure B-8 Lateral Support For Intersecting or Return Walls
Figure B-9 Lateral Support For Piers or Stiffened Sections
Wood Frame Tie Forces
ALTERNATE PATH METHOD - 4_023_030109
Factored Loads for Alternate Path Method - 4_023_030110
Plastic Hinge Considerations for AP Modeling of Steel Structures
Nonlinear Analyses of Beam-Columns
Deformation Limits
ADDITIONAL DUCTILITY REQUIREMENTS - 4_023_030114
Table B-1 Steel Moment Frame Connection Types
Figure B-11 Fully Restrained Connections
Figure B-12 Partially Restrained Connections
Figure B-13 Weak Axis Connections
APPENDIX C. WORKED REINFORCED CONCRETE FRAME EXAMPLE
Loading Assumptions - 4_023_030120
Figure C-1 Reinforced Concrete Building Plan
Member Sizes
ALTERNATE PATH SETUP
Figure C-3 Plan of Removed Column
Progressive Collapse Load Combination - 4_023_030125
ALTERNATE PATH ANALYSIS
Define and Assign Hinge Properties
Define Nonlinear Analysis Cases - 4_023_030128
Progression of Hinge Formations
Figure C-9 Hinges and Deformed Shape (isometric view)
Figure C-10 Hinges and Deformed Shape (x-x single bay)
Table C-4 Properties of Redesigned Members
Shear Capacity and Other Capacity Checks - 4_023_030133
APPENDIX D. WORKED STRUCTURAL STEEL FRAME EXAMPLE TIE FORCE AND NONLINEAR ALTERNATE PATH ANALYSIS
Loading Assumptions - 4_023_030135
Figure D-2 Steel Building Elevation
TIE FORCE CHECK
Table D-2 Required Tie Forces
ALTERNATE LOAD PATH
Figure D-4 Plan of Removed Column
Progressive Collapse Load Combination - 4_023_030141
ALTERNATE LOAD PATH ANALYSIS
Figure D-7 Completed Nonlinear Static Model
Define Nonlinear Analysis Cases - 4_023_030144
Run Analysis
Figure D-10 Hinges and Deformed Shape (isometric view)
Table D-4 Beam and Column Sections for Final Design
Shear Capacity and Other Capacity Checks - 4_023_030148
APPENDIX E. MASONRY CONNECTIONS FOR PROGRESSIVE COLLAPSE DESIGN
Figure E-3. Wood Rafter at Exterior Block Wall
Figure E-6. Precast Concrete Slab Trough Brick Cavity Interior Wall
Figure E-8. Precast Floor Plans at Exterior Block Wall
APPENDIX F. GUIDANCE FOR PROGRESSIVE COLLAPSE DESIGN IN WOOD FRAME STRUCTURES
Figure F-1 Depiction of Barracks Buildings Used in Tie Force Example
Table F-1 Required Tie Forces for Barracks Building
Table F-2 Calculations for Tie Force Wood Member and Connection Design
Table F-2 Calculations for Tie Force Wood Member and Connection Design-continued
Figure F-3 Schematic of Internal and Horizontal Ties
Figure F-5 Schematic of Peripheral and Horizontal Ties; E-W Detail
ALTERNATE PATH METHOD FOR WOOD FRAME CONSTRUCTION
Figure F-7 Illustrations of Rim Beam Use in Wood Frame Construction
Figure F-9 Potential Redistribution of Floor Loads
Example Building
Case 1 Removal of Column in N-S Exterior Wall
Table F-6 Acceptability Criteria Check for Wall Studs
Figure F-10 Cross Section of North-South Exterior Wall
Case 2 Removal of Interior Column
Table F-8 Acceptability Criteria Check for Columns
Figure F-11 Cellular Layout
Figure F-12 Notional Exterior Load Bearing Wall Removal
Summary of Alternate Path Example
APPENDIX G. 2003 INTERNATIONAL BUILDING CODE MODIFICATIONS FOR CONSTRUCTION OF BUILDINGS TO RESIST PROGRESSIVE COLLAPSE
QUALITY ASSURANCE FOR PROGRESSIVE COLLAPSE REQUIREMENTS
[Addition] Contractor responsibility
STRUCTURAL OBSERVATIONS - 4_023_030175
STRUCTURAL OBSERVATIONS - 4_023_030176
4_023_03
