D1 - Knowledge and understanding. The course aims to provide the knowledge that allows facing the structural problems that arise during the interventions on historic buildings. Techniques for assessing the consistency of the various structural parts are discussed, highlighting the static behavior of the structure. Various techniques for stiffening and reinforcing individual structural components are presented. Finally, the methods of mutual solidarization of the structural parts are illustrated so to ensure a good assembly operation and to respond effectively even in the case of seismic excitation. The student is then provided with the tools for proper architectural design of the consolidation and recovery of historic buildings as well as for their improvement of seismic performances. For the understanding of the topics, a guided application of the acquired theoretical tools in the strengthening design of an existing masonry construction is carried out.
D2 - Applying knowledge and understanding. The student will be able to independently recognize the critical issues concerning existing masonry constructions and to perform an adequate diagnostic analysis. It will also have to be able to apply the reinforcement measures suitable to remove the structural criticalities found.
D3 - Making judgments. The student will be able to choose the most suitable type of reinforcement and to perform the correct sizing to ensure adequate static and seismic performances.
D4 - Communication skills. The student will be able to fully describe the phases of investigation, diagnostics and intervention in the technical report of the project and will be able to illustrate with proper language the properties of the developed project.
D5 - Learning skills. At the end of the course the student will have to be able to independently deal with insights and specialist integrations concerning the reinforcement techniques and improvement of seismic performances of existing masonry buildings.

The student must have acquired knowledge about statics, structural analysis and structural design.

The topics discussed in the course are:
• Knowledge investigations and structural assessment: structural safety, risk of loss of functionality or collapse. Historical investigation. Cracking wall survey. Monitoring and diagnostics for restoration.
• Notes on foundations: remarks of the carrying capacity of the superficial foundations (Terzaghi, Meyerhof, Vesic). Calculation of vertical stresses in the soil (Boussinesq, Newmark). Calculation of the settlements. Bearing capacity of deep foundation: piles, diaphragms.
• Masonry Checks: Introduction to the semi-probabilistic method for limit states. Static design of masonry buildings. Check for compression, combined flexure-compression and shear of masonry walls. Distribution of vertical loads on masonry walls.
• Seismic behavior of the buildings: Horizontal actions due to earthquakes: elastic and design spectrums. Stiffness of shear walls. Distribution of horizontal actions among shear walls. Resistance of shear walls and spandrels. Masonry walls subjected to out-of-plane actions. Knowledge levels for seismic analysis of existing buildings. Analysis of a historic building subjected to seismic actions.
• Experimental Investigations. Masonry resistance: experimental tests for detection of compression resistance (sampling, flat jacks, etc.). Tests for shear resistance.
• Masonry interventions: repairs through substitution of damaged parts of masonry or through reinforced drilling. Injection of binding mixtures; reinforced coating applied on both masonry surfaces; diffused reinforced perforations. Application of vertical or horizontal steel ties. Strengthening through the use of composite materials.
• Interventions on the floors: Strengthening and stiffening of wooden floors (concrete slab in collaboration, use of steel diagonals or made with carbon sheets and perimetral steel elements). Calculation of the bearing capacity of strengthened floors. Intervention techniques on roofs. Contrasting horizontal thrusts.
• Connections between floors and walls: techniques for connecting wooden floors through metal pins (injected and passing through). Methods of calculating the resistance to shear and tension of the pins. Connections between the floors and the masonry (dovetails, tie beams inside the masonry).
• Foundation interventions: intervention techniques for injections, new fondations under the wall and widening of the base. Reinforced foundations with piles or micropiles.
• Arches and vaults: static design of curved structures. Mechanics of arches. Calculation methods: analytical and graphical procedures. Consolidation of cracked members. Increased carrying capacity (adding chains, making concrete adding vault, lightening infilling).
• Seismic behavior of mixed structures: types of mixed structures: concrete-masonry, concrete-steel, steel-masonry. Seismic behavior of structures with infilled frames, frames or vertical stiffeners of concrete or steel in masonry structures.

Mastrodicasa S., “Dissesti statici delle strutture edilizie”, Ed. Hoepli.
Tomazevic M., “Earthquake-Resistant Design of Masonry Buildings”, Imperial College Press, Vol. 1, 2001, London.
Hendry A.W., “Statica delle strutture in muratura di mattoni”, Patron Editore.
Croci G., “Conservazione e restauro strutturale dei beni architettonici”, UTET, Torino, 2001.

The course includes both lectures for the theoretical discussion of the topics related to the strengthening of historic buildings and development of an intervention project on an existing building for its requalification. The student will be guided in drawing up the documents required.

Theoretical lectures concerning diagnostics and structural restoration will be given. The student has to take two partial written tests where the acquisition of the topics treated in the lectures will be verified. Unsuccessful tests have to be retrieved by an oral interview that will take place just before the examination of the laboratory project.
For the project of the IV Architectural Design Laboratory, the students have to develop specific parts concerning structural rehabilitation and seismic structural improvements with verification of the main structural elements.
Design drawings for the structural part should be quoted and should include: foundation plan, floor plan and roof plan with clear indication of the arrangement of the structures, two vertical sections in two orthogonal directions, constructive details of connections between structural elements. Graphic drawings have to be accompanied by a report, describing structural choices, resistive mechanisms and calculations that have allowed the design and verification of structural elements.