![]()
1 Introduction
This text is intended for a senior level course for civil engineering students whose focus is structural engineering. The material may also be useful for graduate level courses and as a reference for practicing structural engineers. First courses in structural analysis, structural steel design, and reinforced concrete design should be considered prerequisites to the material covered here.
The basis of this book is course notes developed by the author for courses in advanced structural design, bridge design, and earthquake engineering at Tennessee State University and Tennessee Technological University after 35 years of structural engineering practice.
The material in this book may be studied most effectively with several tools in hand. These are freely available.
- 1. AISC 360-16 Specification for Structural Steel Buildings
- 2. AISC 341-16 Seismic Provisions for Structural Steel Buildings
- 3. AISC 358-16 Prequalified Connections for Special and Intermediate Steel Moment Frames for Seismic Applications
- 4. SeismoStruct Educational Version – Nonlinear Static & Dynamic Structural Analysis
- 5. SeismoMatch Educational Version – Spectral Matching in the Time Domain
- 6. SeismoArtif Educational Version – Spectral Matching in the Frequency Domain
- 7. IES VisualAnalysis Educational Version – Structural Design Software
- 8. SigmaSpectra – Ground Motion Scaling and Selection Tool
The AISC Standards may be downloaded from aisc.org. The SeismoSoft applications are available from seismosoft.com. IES VisualAnalysis Educational can be downloaded from iesweb.com/edu. SigmaSpectra, by Albert Kottke, is available at GitHub.
The book is not intended to be a comprehensive treatment of any single subject in the field of structural engineering, but to familiarize and summarize for the structural engineering advanced student as well as the practicing engineer, a variety of topics.
While it is most often necessary to use software in modern structural design, the engineer should have the ability to perform sanity checks on software results, and to estimate values for design parameters using hand calculations and simplifications. The material presented here will be of assistance in completing such tasks.
Topics from both building and bridge design are included and serve to enhance an undergraduate curriculum. Examples are included throughout each chapter.
Chapter 2 presents a discussion of various types of structural analysis including linear elastic versus nonlinear analysis, first-order versus second-order analysis, and response spectrum analysis versus response history analysis. The chapter also includes a brief discussion on seismic site response analysis. Finally, a detailed presentation of the substitute structure method for inelastic seismic response is presented.
Chapter 3 presents topics unique to the design of buildings. Composite beam design is discussed, followed by an outline and examples of the AISC direct analysis method for stability. Plastic analysis techniques, important in seismic and blast-resistant design, are covered, as are requirements from design specifications related to plastic design, also known as inelastic design. Various lateral force resisting systems and design philosophies are covered prior to connection design in steel. Issues related to computer modeling of buildings, vertical and horizontal seismic load distribution, and the design of moment resistant column bases finish out Chapter 3.
Bridge loads, limit states, and load combinations are discussed in detail in Chapter 4, followed by a presentation of issues related to both prestressed concrete and structural steel superstructures for bridges. Substructures and foundation systems commonly used in bridges are covered in Chapter 4. Earthquake effects on bridges, in terms of seismic design philosophies, seismic isolation, and pushover analysis techniques, are followed by a brief treatment on the computer modeling of bridges.
Chapter 5 is a description of earthquake loading as applied to structures, whether buildings, bridges, or other. Baseline adjustment and filtering of ground motion, as well as the computation of various ground motion parameters and response spectra, are included. Requirements found in various ASCE design specifications are presented, along with a discussion on the importance of ground motion directionality and statistical considerations. Ground motion databases available to the engineer and scientist are identified followed by material on ground motion models, ground motion selection, and ground motion modification for structural analysis.
Chapter 6 provides the reader with example problems to solve for a clearer understanding of the design concepts presented in the book.
The appendices to the book include hand calculations corresponding to several examples presented. These hand calculations are better presented as appendices to retain the flow of the material presented in the main body.
![]()
2 Analysis Techniques for the Structural Engineer
Static structural analysis by any of the following methods may be accomplished. The method appropriate for a particular problem depends on the expected level of structural response. Nonlinear effects may be broadly categorized as (a) geometric and (b) material. Geometric nonlinearity refers to PΔ and Pδ effects, while material nonlinearity refers to strains beyond the yield point. PΔ effects refer to moment and deflection amplification which occur when compression member ends experience relative translation. Pδ effects refer to moment and deflection amplification which occur when no member end relative translation exists, but transverse loads between member ends exist in compression members.
- First-Order Elastic Analysis: neglects all nonlinearities and is typically a good indicator of service load conditions.
- Second-Order Elastic Analysis: PΔ and Pδ effects are included, but no material nonlinearity is in...
