Jerome J. Connor Susan Faraji. Fundamentals of Structural. Engineering. ^ Springer

Transcription

1 Jerome J. Connor Susan Faraji Fundamentals of Structural Engineering ^ Springer

2 Contents Part I Statically Determinate Structures 1 Introduction to Structural Engineering Types of Structures and Structural Components Structural Components Types of Structures Critical Concerns of Structural Engineering Reactions Initial Stability Loss of Stability Due to Material Failure Buckling Failure Mode Priorities for Stability Types of Loads Source of Loads Properties of Loadings Gravity Live Loads Wind Loading Snow Loading Earthquake Loading Structural Design Philosophy Basic Analytical Tools of Structural Analysis Concept of Equilibrium-Concurrent Force System Concept of Equilibrium: Non-concurrent Force System Idealized Structure: Free Body Diagrams Internal Forces Deformations and Displacements Structural Behavior; Structural Analysis The Importance of Displacements Summary Objectives of the Chapter Key Issues and Concepts Introduced 47 XV

3 xvj Contents 2 Statically Determinate Truss Structures Introduction: Types of Truss Structures Structural Idealization Historical Background Analysis of Planar Trusses Equilibrium Considerations Statically Determinate Planar Trusses Stability Criterion Method of Joints: Planar Trusses Method of Sections Complex Trusses Computation of Deflections Introduction Force-Deformation Relationship Deformation-Displacement Relations Method of Virtual Forces Influence Lines Analysis of Three-Dimensional Trusses Introduction Restraining Rigid Body Motion Static Determinacy Method of Joints for 3-D Trusses Matrix Formulation: Equilibrium Analysis of Statically Determinate 3-D Trusses Notation Member-Node Incidence Force Equilibrium Equations Stability Matrix Formulation: Computation of Displacements Summary Objectives of the Chapter Key Facts and Concepts Problems Statically Determinate Beams Definition of a Prismatic Beam Stability and Determinacy of Beams: Planar Bending Fixed Support: Planar Loading Hinged Support: Planar Loading Roller Support: Planar Loading D Fixed Support D Hinged Support D Roller Support: Z Direction Static Determinacy: Planar Beam Systems Unstable Support Arrangements 193

4 Contents xvii Beam with Multiple Supports Beam with a Moment Release Reactions: Planar Loading Internal Forces: Planar Loading Differential Equations of Equilibrium: Planar Loading Displacement and Deformation of Slender Beams: Planar Loading Moment: Curvature Relationship Qualitative Reasoning about Deflected Shapes Moment Area Theorems Computing Displacements with the Conjugate Beam Method Computing Displacements with the Method of Virtual Forces Computing Displacements for Non-prismatic Members Deformation-Displacement Relations for Deep Beams: Planar Loading Torsion of Prismatic Members Symmetry and Anti-symmetry Symmetry and Anti-symmetry: Shear and Moment Diagrams Symmetry and Anti-Symmetry: Deflected Shapes Influence Lines and Force Envelopes for Statically Determinate Beams The Engineering Process Influence Lines Force Envelopes Summary Objectives of the Chapter Key Facts and Concepts Problems Statically Determinate Plane Frames Definition of Plane Frames Statical Determinacy: Planar Loading Analysis of Statically Determinate Frames Behavior of Portal Frames: Analytical Solution Pitched Roof Frames Member Loads Analytical Solutions for Pitched Roof Frames A-Frames 396

5 xvjjj Contents 4.6 Deflection of Frames Using the Principle of Virtual Forces Deflection Profiles: Plane Frame Structures Computer-Based Analysis: Plane Frames Plane Frames: Out of Plane Loading 4.10 Summary Objectives Key Concepts 4.11 Problems 5 Cable Structures 5.1 Introduction Cables Subjected to Concentrated Loads Horizontal Cables Inclined Cables Cables Subjected to Distributed Loading Horizontal Cable: Uniform Loading per Horizontal Projection Inclined Cables 5.4 Advanced Topics Arc Length Equivalent Axial Stiffness Equivalent Axial Stiffness for an Inclined Cable Cable Shape Under Self Weight: Catenary Summary Objectives Key Concepts 5.6 Problems Statically Determinate Curved Members A Brief History of Arch-Type Structures Modeling of Arch Structures Internal Forces in Curved Members Parabolic Geometry Method of Virtual Forces for Curved Members Non-shallow Slender Curved Members Shallow Slender Curved Members Circular Curved Member Analysis of Three-Hinged Arches Summary Objectives Key Factors and Concepts 6.8 Problems

6 Contents xix 7 Shallow Foundations Introduction Types of Foundations Types of Shallow Foundations Soil Pressure Distribution An Analytical Method for Evaluating the Soil Pressure Distribution under a Footing Dimensioning a Single Rectangular Footing Dimensioning Combined Footings Dimensioning Strap Footings Summary Objectives of the Chapter Problems Vertical Retaining Wall Structures Introduction Types of Retaining Walls Gravity Walls Cantilever Walls Force Due to the Backfill Material Different Types of Materials Rankine Theory: Active Soil Pressure Stability Analysis of Retaining Walls Pressure Distribution Under the Wall Footing Critical Sections for Design of Cantilever Walls Summary Objectives of the Chapter Key Concepts and Facts Problems 628 Part II Statically Indeterminate Structures 9 The Force Method Introduction Maxwell's Law of Reciprocal Displacements Application of the Force Method to Beam-Type Structures Beam with Yielding Supports Fixed-Ended Beams Analytical Solutions for Multi-span Beams Application to Arch-Type Structures Application to Frame-Type Structures General Approach Portal Frames Pitched Roof Frames 707

7 xx Contents 9.6 Indeterminate Trusses Summary Objectives Key Factors and Concepts Problems The Displacement Method Introduction Displacement Method Applied 10.3 Member Equations for Frame-Type Structures The Displacement Method Applied to Beam Structures 747 to a Plane Truss Two Span Beams The Displacement Method Applied to Rigid Frames Portal Frames: Symmetrical Loading Portal Frames Anti-symmetrical Loading The Moment Distribution Solution Procedure for Multi-span Beams Introduction Incorporation of Moment Releases at Supports Moment Distribution for Multiple Free Nodes Moment Distribution: Frame Structures Frames: No Sideway Frames with Sideway Plane Frames: Out of Plane Loading Slope-Deflection Equations: Out of Plane Loading Summary Objectives Key Factors and Concepts Problems Approximate Methods for Estimating Forces in Statically Indeterminate Structures Introduction Multi-span Beams: Gravity Loading Basic Data-Moment Diagrams Quantitative Reasoning Based on Relative Stiffness Multistory Rigid Frames: Gravity Loading Multistory Rigid Frames: Lateral Loading Portal Method Shear Stiffness Method: Low-Rise Rigid Frames Low-Rise Rigid Frames with Bracing 863

8 Contents xxi 11.5 High-Rise Rigid Frames: The Cantilever Method Summary Objectives of the Chapter Key Concepts Problems Finite Element Displacement Method for Framed Structures Introduction Key Steps of the Finite Element Displacement Method for Member Systems Matrix Formulation of the Member Equations: Planar Behavior Local and Global Reference Frames Nodal Force Equilibrium Equations Introduction of Nodal Supports Systematic Approach Specialized Formulation for Beam and Truss Structures The Steps Involved for Plane Truss Structures The Steps Involved for Beam Structures with Transverse Loading Three-Dimensional Formulation Summary Objectives Problems 939 Part III Practice of Structural Engineering 13 Multi-span Horizontal Structures The Engineering Process for Girders Influence Lines for Indeterminate Beams Using Miiller-Breslau Principle Engineering Issues for Multi-span Girder Bridges Geometric Configurations Choice of Span Lengths Live Loads for Multi-span Highway Bridge Girders: Moment Envelopes Loading Due to Support Settlements Case Studies Case Study I: A Three-Span Continuous Girder Bridge Case Study II: Two-Hinged Parabolic Arch Response: Truck Loading 982

9 xxii Contents Case Study III: Three-Span Parabolic Arch Response: Truck Loading Case Study IV: Cable-Stayed Bridge Summary Objectives Key Facts and Concepts Problems Lateral Load Issues for Buildings Types of Multistory Building Systems Treatment of Lateral Loading Wind Loading Earthquake Loading Building Response Under Lateral Loads Center of Twist: One Story Frame Center of Mass: One Story Frame One Story Frame: General Response Multistory Response Matrix Formulation: Shear Beam Model Response of Symmetrical Buildings Summary Objectives Key Facts and Concepts Problems Vertical Loads on Multistory Buildings Loads on Frames Treatment of Gravity Floor Loads Live Load Patterns for Frame Structures A Case Study: Four-Story Building Building Details and Objectives Analysis Procedures for Bracing Scheme Case (1) Frames Are Braced in Both N-S and E-W Directions: Building Details Case (1) Beam Properties in the N-S and E-W Directions Case (1) Bracing Systems Case (1) Interior Columns Summary for Case (1) Case (2) Frames Are Rigid in the N-S Direction but Remain Braced in the E-W Direction Strategy for N-S Beams and Columns Live Load Patterns 1102

10 Contents xxi" Moment 105 Diagrams Design Values Summary for Case (2) Summary 11 ' Objectives H Key Concepts Problems H'3 References Index ''