Civil Engineering

The course will cover the following main aspects: • Overview of key and most common structural weaknesses and associated anticipated behaviour/response of existing reinforced concrete buildings. Reference will be given to experimental tests, analytical/numerical studies and the recent lessons learnt from post-earthquake building inspections and investigations. • Discussion on main features and approaches of alternative seismic assessment procedures, with reference to existing national and international literature. • Fundamentals of analytical and numerical modeling techniques to represent the seismic response of as-built reinforced concrete buildings • Introduction to Performance-Based Retrofit Strategies and alternative solutions/techniques. • Feasibility and efficiency of adopting and/or combining different solutions such as Fibre Reinforced Polymers, low-invasive low-cost metallic diagonal haunches, (post-tensioning or traditional) wall systems and selective weakening techniques.   The face-to-face main Lectures will cover the following topics, divided in two main Blocks: Assessment and Retrofit BLOCK 1 – STRUCTURAL/SEISMIC ASSESSMENT Introduction to structural/seismic assessment of RC buildings Introduction. Statement of the Problem. Main structural deficiencies of existing reinforced concrete buildings. Seismic performance of existing buildings: observed behaviour in real earthquakes, lessons learned from the Canterbury Earthquake Sequence; experimental/numerical studies and evidences. Seismic assessment methodologies and procedures according to different codes. General principles and approaches. Performance objectives and compliance criteria. Design Classes Introduction to the course project. Case- study buildings. Rapid assessment based on structural drawings to be continued independently as part of the project with more detailed assessment Evaluation of local and global response and mechanisms – Non-linear Modelling Global vs. local mechanisms. Evaluation of hierarchy of strength and sequence of events in as-built structural subassemblies and systems. Vulnerability and behaviour of elements and connections, e.g. columns, beams, beam-column joints, walls, floor-to-lateral resisting systems Interaction of bare frame systems with “non-structural” masonry or concrete infills. Simplified Modelling techniques based on lumped plasticity (macro) models. Numerical investigations on the response of pre-1970 frames with and without infills. Design Classes – Moment-curvature of structural elements. Flexure, shear, flexural-shear interaction and strength degradation. Hierarchy of strengths and sequence of events for a beam-column joint. Modelling of columns, beam-column joints and frame systems using lumped plasticity approach. BLOCK 2 - RETROFIT STRATEGIES AND TECHNIQUES Introduction to Seismic Retrofit Strategies- Fiber Reinforced Polymers FRP Overview of Alternative retrofit strategies and techniques. Performance-based and displacement based retrofit approach. Introduction to Fibre Reinforced Polymers, FRP. Design and applications. Upgrading for flexural, shear and confinement. Seismic Strengthening of beam- column joints with FRP Design Classes Design example and application of FRP strengthening of a structural element for flexure, shear and confinement and of a beam-column joint subassembly to improve the sequence of events. Retrofit Solutions using external walls, diagonal haunch or selective weakening Retrofit using mini-brace in the form of a diagonal metallic haunch. Concept, design and experimental validation. Displacement-Based Retrofit approach using rocking-dissipative walls. Principles and examples of selective weakening strategies and techniques Design Class Design Class. Haunch retrofit evaluation and modelling using macromodels (e.g. SAP2000, Ruaumoko)

Basic knowledge and competence on Structural Design and Earthquake Engineering are required to form the basis for the evaluation of the capacity (force/moment vs. curvature/rotation) of structural elements.

Handouts of the lectures will be provided in .pdf form A selection of suggested reading material on the topics covered in class will also be provided in electronic form and uploaded on a common repository (DropBox-type). A short (indicative and limited) list of suggested reading related to international guidelines on assessment and retrofit is given below: ASCE 41-13, Seismic Evaluation and Retrofit of Existing Buildings, American Society of Civil Engineers and Structural Engineering Institute (ASCE and SEI), Reston, Virginia, USA. EN 1998-3, Eurocode 8: Design of Structures for Earthquake Resistance, in Part 3: Assessment and Retrofitting of Buildings, European Committee for Standardization (CEN), Updated in 2005 FEMA 273, 1997, Guidelines to the Seismic Rehabilitation of Existing Buildings, Federal Emergency Management Agency, Washington, D.C FEMA 274, 1997, NEHRP Commentary on the Guidelines for the Seismic Rehabilitation of Buildings, Federal Emergency Management Agency, Washington, D.C fib, 2003, Seismic Assessment and Retrofit of Reinforced Concrete Buildings: State-of-the-art report. Bulletin 24, fib Task Group 7.1, International Federation for Structural Concrete (fib), Lausanne, Switzerland. NTC 2008, Norme tecniche per le costruzioni, (Code Standard for Constructions), In Italian, Ministry of onfrastructures and Transport, MIT, Rome NZSEE 2017, The Seismic Assessment of Existing Buildings (the Guidelines), New Zealand Society of Earthquake Engineering, Wellington, Version October 2016, http://www.eq-assess.org.nz/

The course will comprise face-to-face lectures and a group project. The time-schedule of the overall lectures will be structured around the two aforementioned Blocks with one Study Week and Modeling Workshop organized at around mid-semester. As part of the assignment/project requirements, students, either individually or paired in groups, will be assigned a case-study project. The project work will cover aspects of simplified or detailed assessment, analytical and numerical modelling of the structural response, conceptual design and performance evaluation of alternative retrofit solutions for a case study building. Details on the case-study prototype building, type of analysis to carry, level of design vs. assessment (and possibly retrofit) will be discussed and agreed with each group. The main findings will be presented via a written report, divided in two parts, assessment and retrofit, respectively, as well as via an oral/project presentation. Options for Mid-term examinations (“Esoneri”) will be available (optional) in discussion with the Professor in charge. Regular Reviews will be carried out to assist/support the groups during the development of the their project. Indicative and mandatory deadlines on each sub-tasks of the project will be provided at the beginning of the course and adjusted in agreement with the class to follow the students' pace and specific needs (mostly due to different theoretical background on some topics)

Design Project/Assignments: As part of the assignment/project requirements, students, either individually or paired in groups, will be assigned a case-study project. The project work will cover aspects of simplified or detailed assessment, analytical and numerical modelling of the structural response, conceptual design and performance evaluation of alternative retrofit solutions for a case study building. Details on the case-study prototype building, type of analysis to carry, level of design vs. assessment (and possibly retrofit) will be discussed and agreed with each group. The main findings will be presented via a written report, divided in two parts, assessment and retrofit, respectively, and, possibly, an oral presentation. Options for Mid-term examinations (“Esoneri”) will be available (optional) in discussion with the Professor in charge. Assessment/Evaluation The assessment of the exam consist of a project written report and oral presentation (worth 50%) and a final written exam (worth 50%). The written exam will comprise of: 1) essay-type questions to explore the understanding and competence of the students on key concepts as well as to explore the ability to provide design solutions in given hypothetical scenarios 2) analytical (by hand calculation) problems to assess the comprehension of the design procedure as well as the ability to implement simplified approach and engineering judgement to provide a satisfactory solution while solving a quantitative problem with a limited amount of time. The project written report will be evaluated on the basis of the overall structure, organization, professional presentation (including graphs, figures, technical language), content, rigor and appropriateness of the method adopted, critical description of the approach and the results obtained. The oral presentation will be mostly based on the project presentation (using Powerpoint or similar tools) to be carried out in coordination between the project groups members. The presentation will provide the students an opportunity to develop, and be evaluated, on their soft skills, including the ability to technically present their analysis/design work on a (virtual) case-study building to a client assisted by a senior engineer colleagues (i.e. the course professor). During the project presentation the professor will ask technical questions to each member of the group to more comprehensively explore their understanding of the technical background covered in the project as well as of complementary topics taught in class and to further elaborate on their ability to critically and technically discuss about key topics and solutions.

The course will comprise face-to-face lectures and a group project. The time-schedule of the overall lectures will be structured around the two aforementioned Blocks with one Study Week and Modeling Workshop organized at around mid-semester. As part of the assignment/project requirements, students, either individually or paired in groups, will be assigned a case-study project. The project work will cover aspects of simplified or detailed assessment, analytical and numerical modelling of the structural response, conceptual design and performance evaluation of alternative retrofit solutions for a case study building. Details on the case-study prototype building, type of analysis to carry, level of design vs. assessment (and possibly retrofit) will be discussed and agreed with each group. The main findings will be presented via a written report, divided in two parts, assessment and retrofit, respectively, as well as via an oral/project presentation. Options for Mid-term examinations (“Esoneri”) will be available (optional) in discussion with the Professor in charge. Regular Reviews will be carried out to assist/support the groups during the development of the their project. Indicative and mandatory deadlines on each sub-tasks of the project will be provided at the beginning of the course and adjusted in agreement with the class to follow the students' pace and specific needs (mostly due to different theoretical background on some topics)