Steel Structures I

Prerequisite Knowledge

Fundamental mechanics, strength of materials, statics

Course Units

#	Title	Description	Hours
1	Introduction	Course objectives and administrative issues, work phases of structural engineers in steel structures design and construction, types of structural steel projects, production methods of structural steel, hot-rolling, standard sections, shapes of cross-sections, tables of standard sections, cold-forming, thin-walled sections, steel sheeting, built-up sections, stages of production of steel structures, fabrication, erection, mechanical properties of steel, steel grades, comparison between construction materials, advantages and disadvantages of structural steel, the role of design codes, on Eurocodes and Eurocode 3, ultimate and serviceability limit states, actions and resistances, load and material partial factors, loads, load combinations.	1Χ5=5
2	Members in tension	Examples of tension members from practice, mechanical behavior, yielding strength of gross section, ultimate strength of net section, overall tension resistance according to EC3, ductility criterion, staggered bolt holes, critical net section, eccentrically connected members. Application examples.	1Χ5=5
3	Simple bolted and welded connections	Examples of steel connections from practice, general discussion on steel connections, advantages and disadvantages of bolted versus welded connections, selection of appropriate connection type depend on the location and the available options of transportation and erection, bolting geometry, bolt grades, bolt distance limitations, mechanical behavior of simple bolts in shear, bolt shear strength, bearing strength, shear planes, bolts in tension, bolts in combined shear and tension, EC3 specifications, long bolted connections, ductility criterion, welding technology, types of welds (fillet and butt welds, full versus partial penetration, welding faults, quality control, welding strength, EC3 specifications, long welded connections. Application examples.	1Χ5=5
4	Members in compression	Examples of compression members from practice, mechanical behavior, potential failure modes (yielding, flexural buckling, local buckling), equilibrium equations in deformed configuration, differential equation of flexural buckling, critical buckling loads, buckling modes, lateral restraints, interaction between buckling and yielding, influence of initial imperfections, buckling curves, compression resistance according to EC3, flexural buckling about weak and strong axis, local buckling, cross-section classification for compression, influence of boundary conditions, equivalent buckling length, buckling of frame columns. Application examples.	2Χ5=10
5	Laterally restrained members in bending	Examples of members in bending from practice, mechanical behavior, bending and shear, moment of inertia, moment of area, shear area, advantageous cross-section shapes and orientation, elastic verification, interaction of bending and shear, equivalent von Mises stresses, serviceability verification, elastoplastic behavior of cross-section in bending, plastic verification, EC3 specifications, local buckling and cross-section classification for bending. Application examples.	2Χ5=10
6	Torsion and warping	Examples of members in torsion from practice, shear center of different cross-sections, ways to resist torsion, mechanical behavior of bar with solid circular cross-section in torsion, torsional constant, behavior of hollow sections, pure or St. Venant torsion, behavior of open sections, warping, stresses due to warping, differential equation of torsion and warping, EC3 specifications. Application examples.	1Χ5=5
7	Laterally unrestrained members in bending	Concept and mechanism of lateral-torsional buckling, behavior of closed and open sections, differential equation of lateral-torsional buckling, elastic critical lateral-torsional buckling moment, influence of bending moment diagram, location of load application over the cross-section and boundary conditions, EC3 specifications, lateral restraints. Application examples.	1Χ5=5
8	Sections under combined action effects	Examples from practice, stresses due to each action effect, equivalent stress and elastic verification, plastic interaction between axial force, shear forces and bending moments for different cross-section shapes, interaction diagrams, EC3 specifications. Application examples.	1Χ5=5
9	Members under combined action effects	Examples from practice, possible failure mechanisms of members under combined axial force and bending moments (yielding, flexural buckling about weak/strong axis, local buckling, lateral-torsional buckling), nonlinear interaction between combined axial force and bending moment, differential equation of equilibrium, coefficient of elastic interaction, EC3 specifications. Application examples.	1Χ5=5
10	Structural layout of typical single-story industrial steel buildings	Examples from practice, geometrical considerations, main structural members (main frames, bracing systems, purlins, head-beams, frontal columns) and their structural function, load resisting mechanisms, common cross-sections and their orientation, typical connections. Application examples.	1Χ5=5

Learning Objectives

Upon the successful completion of the course, the students will be able to:

• Understand the mechanical behavior of beam-type steel members and their connections.
• Identify their possible failure mechanisms.
• Check their adequacy and dimension them according to Eurocode 3.
• Comprehend the structural system of simple steel structures (single-story industrial buildings, pedestrian bridges)

Teaching Methods

Teaching methods	- In-class lectures. - Solution of simple examples and case studies in class. In every course section, the theoretical background is analyzed, according to the theory of mechanics and strength of materials. Then, the necessary verification checks are presented, according to Eurocode 3 provisions. Emphasis is given on connecting the theoretical background with the code provisions, so that the students can easily adjust to future changes in the code. Technical as well as construction issues are discussed, while numerical applications, inspired from actual projects, are solved as exercises.
Teaching media	PowerPoint presentations Additional material presented on the black board.
Problems - Applications	Yes

Student Assessment

• Final written exam: 70%
• Mid-term exam: 30%

Textbooks - Bibliography

• I. Vayas, I. Ermopoulos, G. Ioannidis, «Design of steel structures with application examples», Kleidarithmos Publications, Athens, 2005.
• I. Vayas, C. Gantes, I. Ermopoulos, G. Ioannidis, «Application examples for special issues in steel structures», Kleidarithmos Publications, Athens, 2013.
• Educational material from the course website.

Lecture Time - Place:

• Thursday, 10:45 – 12:30,
  Rooms:
  • Ζ. Κτ. 1 Πολ., Αιθ. 12
• Friday, 09:45 – 12:30,
  Rooms:
  • Ζ. Κτ. 1 Πολ., Αιθ. 1
  • Ζ. Κτ. 1 Πολ., Αιθ. 7