35125 - Building Techniques M (L-Z)

Learning outcomes

The course aims at providing the design techniques for the main structural typologies and the expertise for the critic examination of the actual technical codes.

Real examples and applications teach the right way to face the structural design.

Course contents

STRUCTURAL RELIABILITY:

Random Variable (RV). Discrete RV. Histograms. PDF (Probability Density Function). Mean, variance, coefficient of variation. Continuous RV. Probability Density Function) and CDF (Cumulative Distribution Function). Mean, variance, coefficient of variation, median. Distributions: Gauss, standard Gauss function  fi(s), uniform. Tables of function  fi(s). Characteristic value (fractile 5%). numerical definition of characteristic values. statistical independence of RV. Serial and parallel structures. RV sum of RVs. The fundamental case. Limit state function g(x)=R-S. Reliability index Beta. Observation on the fundamental case.

BEAM SYSTEMS:

Rigid connection, semi-rigid connection, hinge connection. Equilibrium method. Classical stiffness matrix (direct method calculation). Simplified method. Analytical description of a beam on elastic soil: exact solution and applicative cases (unlimited and semi-unlimited beams).

DUCTILITY OF RC STRUCTURES.

Ductilityof construction materials. Bending moment-curvature diagrams and their bi- and tri-linear simplifications for RC cross sections under flexure. Ductility of cross-section under flexure. Plastic hinges and allowable plastic rotation for RC structural elements under flexure. Effect of axial force on ductility. Examples. Structural ductility.

PLATES UNDER FLEXURE

Kirchhoff's theory for plate under flexure: Lagrange's equation and boundary conditions, Kirchhoff's shear. Simply supported and clamped plates. RC plates: design criteria, construction details. Flat plates and slabs: simplified methods of evaluation of bending moments,design criteria and construction details; punching shear, examples.

 

SHELL STRUCTURES:

Plane structures with in-plane load. Slabs of revolution . Membrane of revolution. Examples for slabs and membranes. Cylindrical r.c. tank. Prestressed tanks. Spherical membrane. Semi-spherical membrane. Conical membrane. Displacements and deformations of membranes. Foundation hoop. Spheric dome: Geckeler solution.

PRESTRESS R.C. STRUCTURES:

Basic theory. Prestress techniques. Stress and strain calculation for statically determined structures. Tension for sliding and adherent cables. Bending for sliding and adherent cables. Post-tension techniques. Technical codes verifications. Structural details and local verifications. Tension loss. Examples.

Readings/Bibliography

Refer to teacher's note for most of the considered arguments.

Ang - Tang, "Probability concepts in engineering palnning and design. Vol. 1: Basic principles", John Wiley, New York, 1975 (per l'affidabilità strutturale).

Ang - Tang, "Probability concepts in engineering palnning and design. Vol. 2: Decision, risk and reliability", John Wiley, New York, 1984 (per l'affidabilità strutturale).

Pozzati, P., Ceccoli, C., "Teoria e Tecnica delle Strutture", UTET, Torino, 1972 (beams).

Belluzzi, O., "Scienza delle Costruzioni" (shells).

Walther, R., Miehlbradt, M., "Progettare in calcestruzzo armato", Hoepli editore, Milano, 1990 (reinforced concrete).

Cestelli-Guidi, C., "Cemento armato precompresso", settima edizione,  Hoepli editore, Milano, 1987 (prestressed reinforced concrete).

Teaching methods

In regular classes, problems concerning the modelling and the design of reinforced concrete structures are discussed. Finally, details of nodes, steel positioning, etc. will be shown and discussed. Guidelines for different structural problems reported in national and international codes will be considered. Some classes will be devoted to show designs of actual realizations concerning the subjects of regular classes.

Assessment methods

The final exam will be an oral colloquium

Teaching tools

Blackboard, overhead projector, video projector

Teacher's note for most of the arguments considered

Office hours

See the website of Claudio Mazzotti