### Lessons

**Lecture 1: Steel–What is it? Advantages and Disadvantages of Steel, how structural steel shapes are made.**

- What is steel?
- Advantages and disadvantages of using it as a building material.
- Advantages: high strength to weight ratio, recyclable, ductile, and tough.
- Disadvantages: corrosion, melts at high temperatures, fatigue sensitive.
- Pictures from an actual steel rolling mill are shown and the process for how steel shapes are made is described.

- Material properties of steel
- Stress-strain curves of various steel types
- Structural shapes: wide-flange, tube, pipe, angles, etc.

**Lecture 3: Specifications, Loads, ASD versus LRFD Design**

- Codes for steel design:
- International Building Code (IBC),
- AASHTO Bridge Design Specifications,
- AISC 360 and the 13th Edition of the Steel Manual.

- Design loads from the ASCE 7 manual
- Design methods: Allowable Stress Design (ASD) and Load and Resistance Factor Design (LRFD).
- “Limit states” of structural failure are defined and described, such as strength and serviceability limit states.
- Differences between ASD and LRFD
- Nominal strengths versus allowable strengths
- Resistance factors (f) versus safety factors (W)
- Service-level loads versus factored loads.
- Load combinations and LRFD load combinations reviewed.

**Lecture 4: Load Combinations, Tension Members**

- ASD load combinations example.
- Tension members limit states:
- Yielding on the gross cross sectional area
- Rupture on the net effective area.
- Example of how to calculate the net area thru a hole, and what hole size to use with a given bolt size.

**Lecture 5: Organization of the AISC Manual, Tension members with staggered holes, Effective net areas, Shear Lag Factor, U.**

- Photos of actual engineering projects designed by the author with tension members.
- Organization of the AISC Manual, how to navigate it, and where to find the Specification in the manual.
- Spec Chapter D, Tension Members nominal capacity.
- How to calculate the net area through a tension member with staggered holes,
- The shear lag factor, U, explained.

**Lecture 6: Bolted and welded tension member examples, Connecting elements in tension.**

- LRFD and ASD capacities of two different tension members: one bolted and one welded
- How to calculate the effective net areas for both including shear lag.
- Where to find the provisions for connecting elements in tension

**Lecture 7: Connecting element in tension example, Block shear, Block Shear Example**

- Connecting elements in tension
- Net effective area limitation for connecting elements
- Connecting element example
- Block Shear for tension members with an example

**Lecture 8: Design of Tension members, Slenderness ratio for tension members, Threaded Rod tension members**

- Design of tension members
- How to determine the area required based on a given tensile loading
- Design steps for tension members
- Slenderness recommendation for tension members.
- Example of the design of a tension member
- Threaded rod tension members

**Lecture 9: Threaded Rod tension members, Compression members–Flexural (Euler) Buckling v. Local Buckling, Effective length (K) factors, Slenderness ratio**

- Threaded rod tension members: nominal strength from AISC Spec
- 3-hinged arch tension tie problem
- Compression members (columns)
- Column limit states:
- Flexural buckling
- Local buckling
- Flexural-torsional buckling

- Column slendernerss ratio, L/r
- Effective Length factor, K

**Lecture 10: Effective length factors for braced and unbraced frames, Euler Buckling column capacity**

- K factors for sidesway frames (moment frames) and for braced frames (non-sway frames)
- Approximate K values for typical columns
- Column strength dependence on effective slenderness
- Graph for short, intermediate, and long columns.
- Short and Intermediate columns fail by a combo of yielding and buckling (called inelastic buckling)
- Long columns fail by elastic buckling, also called Euler Buckling.
- AISC equations for the critical column stress, Fcr,
- Example problem: capacity of a wide-flange column three different ways:
- AISC equations (fast)
- AISC Table 4-22 (faster)
- AISC Table 4-1 (fastest)

**Lecture 11: Determining which buckling axis controls column capacity, local buckling; Compact, Noncompact and Slender sections (Local Buckling)**

- How column strength depends on which direction a column buckles:
- Strong (x-x) axis or weak (y-y) axis buckling
- Depends on the direction with the longer effective slenderness ratio.

- Column strength example with slenderness ratio in the strong direction (KLx) controls.
- How to convert KLx to an equivalent KLy in order to use AISC Table 4-1
- How to do the problem using Table 4-22.
- Local buckling of compression members
- Stiffened and unstiffened elements of a section
- Width-thickness ratio, b/t
- Compact, noncompact and slender sections

**Lecture 12: Local Buckling, column capacity example, Torsional buckling**

- Local buckling (LB) part 2
- Review of compact, noncompact or slender categories
- b/t limits shown in AISC Table B4.1
- We show how AISC Table 4-1 flags whether a section is noncompact and already accounts for LB in its compression strength capacities
- Column example showing how to find out if it’s slender
- What is torsional buckling in columns and how does it occur?

**Lecture 13: Compression Member examples**

- A number of compression member examples are worked, showing you how to quickly determine column sizes using the Tables in Part 4 of the AISC Manual.
- Built-up columns also briefly discussed

**L****ecture 14: Single angles in compression, Columns in frames, K factors in sidesway frames**

- Single angles compression members
- Examples and photos of columns in steel building frames
- How effective length (K) factors can be estimated for columns in frames using a commonly-used nomograph.

**L****ecture 15: K factors in sidesway frames, column baseplates**

- Continued discussion on how K factors can be estimated for columns in frames
- Example showing how to use the nomograph chart to find K.
- Another example of sizing a wide-flange column in a frame using a K value determined from the nomograph
- Design column base plates—Part 1

**Lecture 16: Column baseplate design and example**

- Design of column base plates—Part 2
- Column base plate design example for wide-flange column

**Lecture 17: Intro to Beams, Elastic and Plastic Section Modulus, Bending stresses**

- Design of steel beams, one of the most important topics in steel design.
- What is a beam?
- Basic concepts of bending stresses in a beam
- What is the yield moment in a beam?
- What is the plastic moment and what is a “plastic hinge” in a beam?
- How to find bending stresses using the flexure formula
- Simple example of beam bending stresses
- What is the plastic section modulus, Z, and do you find it? (Note: There is a small error at the end of the video in how Z is calculated which is corrected in Lecture 18.

**Lecture 18: Design of Beams, Lateral Torsional Buckling (LTB), Unbraced Length, Bending Capacities: Plastic (Zone 1), Inelastic LTB (Zone 2), Elastic LTB (Zone 3) **

- Review bending stresses in beams
- Review how Z is calculated, correcting the small error from Lecture 17.
- What is Lateral Torsional Buckling (LTB) in beams?
- How LTB be prevented by bracing the compression side of a beam.
- Bending strength of a beam and strength based on its unbraced length, Lb.
- Methods of laterally bracing a beam: by metal deck, other beams or joists.
- Photo of metal decking on steel beams from an actual steel building project.
- Bending strength (moment capacity) of a beam gets smaller as the unbraced length, Lb, increases.
- 3 zones of bending strength of a beam versus its unbraced length:
- Plastic (Zone 1)
- Inelastic LTB (Zone 2)
- Elastic LTB (Zone 3)

- Design of beams in Zone 1: fully plastic capacity
- Example of beam in Zone 1

**Lecture 19: Design of Beams in Zone 1, 2, and 3**

- 2 beam design examples with its unbraced length equal to zero
- Review beam moment capacity in Zones 1, 2, and 3 (Plastic, Inelastic Lateral Torsional Buckling, and Elastic LTB)
- What is the lateral torsional buckling modification factor, Cb
- What is the Bending Factor in AISC Table 3-2
- Beam design example with its unbraced length of 8′-0″

**Lecture 20: Design of Beams using AISC Table 3-10, Local Buckling of beams**

- Video showing lateral torsional buckling in 3D
- Design of beams in Zone 3, elastic lateral torsional buckling
- AISC Table 3-10, moment capacity of W shaped beams for any unbraced length
- Beam design example using AISC Table 3-10 and unbraced length of 20′-0″
- Local buckling of beams using AISC Table B4.1 for width-thickness ratios

**Lecture 21: Shear and Deflection of Beams**

- When is shear critical in steel beams?
- Shear stresses in beams
- Shear capacity using the AISC provisions of Specification Chapter G
- What is the web shear coefficient, Cv?
- Beam shear example
- Beam deflections–when are they critical?
- Beam deflection example showing how to find lightest section based on moment of inertia using AISC Table 3-3

**Lecture 22: Shear and Deflection of Beams, Beams with concentrated forces, Beam bearing plates**

- Beam deflections using a simplified AISC equation
- Webs and flanges of beams with concentrated loads: web crippling, web yielding, local flange bending
- AISC Chapter J.10 provisions for beams with concentrated forces
- Beam bearing plates and a bearing plate example

**Lecture 23: Biaxial Bending of beams, Shear Center, Combined bending and axial force (beam-columns), drag struts**

- Examples of biaxial bending of beams: crane runway beams, roof purlins, AISC equations for biaxial bending
- Shear Center: torsion on open and closed sections
- AISC User Note F1.1: Selection Table for the Application of Chapter F Sections
- Examples of beam columns: rigid frames, most building columns, drag struts, explanation of a drag strut

**Lecture 24: Beam-columns, second-order (P-Delta) effects, Amplified First-Order Elastic Analysis, Cm factors**

- Beam-column example: top chord of a truss
- AISC Chapter H equations for beam columns
- Second order effects (P-Delta) effects based on AISC Chapter C, Stability Analysis and Design
- The difference between member p-d effects and frame drift P-D effects
- First-order analysis versus second-order analysis
- Amplified first-order analysis to approximate second-order effects
- Magnification (amplification) factors B
_{1}for p-d effects and B_{2}for P-D effects - How to calculate Cm for use in B
_{1}equation - Example problem: check a tube column with axial load and moment

**Lecture 25: Beam-column examples: HSS Tube column and WF column with bending**

- Example problem: finish checking the tube from last lecture as a beam-column
- Example problem: WF beam-column design
- Exam #2 discussion

**Lecture 26: High-strength Bolted connections, Types of Bolts, Tightness of Bolts, Bolt shear failure modes and shear strength**

- Why use bolted connections; advantages of bolted connections
- What are rivets and why did bolts replace them
- Types of bolts: A307, A325, A490
- Bolt tightness: Snug Tight (ST), Pretensioned (PT), Slip-Critical (SC) and what are they and when do you specify them
- Methods to tighten bolts to PT or SC tightness: Turn of the Nut, Calibrated Wrench, Direct Tension Indicator, Twist-off or Tension-Controlled Bolts
- Examples of Bolts in Shear and Tension
- Bolts in single shear and double shear
- Shear failure modes: bolt shear, rupture on net section, bearing failure of plate, shear tearout
- Bolts in combination with welds: need SC bolts
- Bolt hole sizes: Standard, oversize, short-slotted, long-slotted
- Minimum spacing and edge distances for bolt holes
- Nominal shear strength of bolts
- Bolt Threads excluded (Type X) versus included (Type N) in the shear plane

**Lecture 27: Shear strength of bolts, Bearing strength of bolts, bolt shear example, Pretensioned (PT) and Slip-critical (SC) bolts, SC bolt example**

- Shear strength of bolts: limit states of bolt shear and plate bearing from AISC Spec section J3
- Bolt shear example problem with 7/8” A325-X bolts using AISC tables to find bolt shear strength
- When are pretensioned or slip-critical bolts used?
- Nominal strength of SC bolts
- SC bolt example using AISC tables to find bolt slip-critical strength

**Lecture 28: Bolts in tension, combined shear and tension in bolts, eccentric shear on bolts (intro), Welds, Advantages/Disadvantages, Types of Welds**

- Example of bolts in tension
- What is prying action on bolts and how do you avoid it?
- Tension capacity of bolts based on AISC Equation J3-1
- Photo of a moment frame connection with pretensioned bolts
- Bolts in combined shear and tension capacity
- When can you ignore combining shear and tension?
- Eccentric shear on a bolt groups
- 3 methods for eccentric shear: Elastic, Effective Eccentricity, and Instantaneous Center of Rotation Methods
- Welding—What is it?
- Advantages and disadvantages of welded joints
- Types of welding: stick versus wire feed welding; SMAW, SAW, FCAW, GMAW processes
- Exam #2 Q&A

**Lecture 29: Weld Inspection methods, Complete Joint Penetration welds, Partial Joint Penetration, fillet welds, plug and slot welds, Weld Symbols**

- Weld Inspection methods: visual, dye penetrant, magnetic particle, ultrasonic, radiographic
- Types of welded joints: fillet welds, groove welds, plug welds
- Complete joint penetration welds versus partial joint penetration groove welds
- Weld Symbols, examples of welded joint symbols

**Lecture 30: Strength of Fillet and groove welds, Fillet weld requirements**

- Effective throat and leg size of fillet welds
- Strength of a fillet welds and groove welds
- Base metal versus weld metal strength
- Weld metal tensile strength, Fu
- Weld electrodes, E70XX, E60XX, etc
- Example of how to calculate strength of 1” long fillet weld
- Fillet weld limitations: minimum length and leg size
- Reduction in strength for long welds
- Maximum fillet weld size

**Lecture 31: Base metal versus fillet weld strength, fillet weld capacity per inch of weld, fillet weld examples, combined bending and shear on weld treated as a line**

- How to tell if base metal or weld metal controls fillet weld strength
- How to quickly calculate the strength of fillet welds per inch of length
- Fillet weld examples
- Fillet weld strength perpendicular verus parallel to the weld axis
- Combined bending and shear on a weld group
- Section properties of weld groups treated as a line

**Lecture 32: Beam connections, Simple Shear Connections, Moment Connections, Design of Single-Plate Shear tab connections**

- Partially Restrained (PR) versus Fully Restrained (FR) connections
- Single Plate Shear Tab connection
- Double Angle shear connection
- Prequalified bolted moment connection—picture and detail
- Prequalified welded moment connection—detail of Reduced Beam Section (RBS) connection
- Design of single plate shear tabs and example problem

**Lecture 33: Final Exam review, Intro to Composite Beams, Intro to Steel Joists and Joist Girders, Intro to Seismic Braced Frames**

- Final exam review
- How to check bolt bearing on the beam web for a single plate shear tab
- What are composite beams? How are composite beam systems erected?
- Picture of composite beam stud welding
- Before and after pictures of complete joint penetration column splice welds showing weld runoff tabs
- Pictures of single plate shear tab connections
- What are steel joists and joist girders?
- Picture and details of typical joists and joist girders
- How are joists and joist girders specified?
- Examples of steel braced frames: Ordinary Concentrically Braced Frame (OCBF), Special Concentric Braced Frame (SCBF), Buckling Restrained Braced Frame (BRBF)
- Pictures of BRBF and SCBF for comparison

**Bonus PowerPoint Video: Real World Steel Design Projects–Case Studies**

**Advanced Lectures: Composite Beam design
**

**Class 1: Intro to design of Composite Beams**

- What are composite beams?
- Drawings and pictures of composite beam systems
- Camber in composite beams
- Erection sequences for unshored versus shored composite beam systems
- Advantages and disadvantages of composite beam systems

**Class 2: Design of Composite Beams**

- How to find the effective slab width
- How does horizontal shear transfer happen in a composite beam?
- How to find the number of required weld studs to transfer the horizontal shear force
- Stud requirements for composite beams with metal deck
- How to find the nominal moment strength of composite beams using AISC Table 3-19.

**Class 3: Composite Beam Design Example**

- Step-by-step example problem of a composite beam design using metal deck and lightweight concrete.
- Beam is sized, camber and number of required studs are determined
- Partial composite action is explained

**Advanced PowerPoint lecture: Second-order effects in steel structure **