Prof. Mark Masia
(Australia)
The University of Newcastle



Title: MASONRY FAÇADES IN AUSTRALIA AND CHALLENGES FOR ENGINEERING RESEARCH AND DESIGN

ABSTRACT

The paper describes challenges for engineering research and design relevant to Australian masonry façade construction. Research aimed at addressing such challenges, being conducted by the author and his colleagues at The University of Newcastle is discussed. The structural safety of new and older existing masonry cavity and veneer wall systems is considered. In particular, the influence on structural reliability, of the spatial and temporal variability of material properties, including aspects such as corrosion of steel wall ties, is addressed. The paper also presents examples of innovations in the design of new masonry façade systems. In recent years architects have lead a revival in the use of masonry in building façade systems in Australia. They have incorporated into their designs textured masonry, stack bonded masonry, and hit and miss (lattice) masonry; they have curved walls in plan and elevation and they have used these various forms in both loadbearing and non-loadbearing applications. This has resulted in challenges for structural engineering design, as many of these forms of masonry construction are not addressed in national design standards. The paper discusses examples and overviews research being conducted to help inform engineering solutions needed to bring architectural visions to life.

BIO

Mark Masia is a Professor at The University of Newcastle, Australia. He obtained his BE in Civil Engineering (1994) and PhD in Structural Engineering (2000) both from The University of Newcastle. His career has included periods in industry as a consulting civil engineer and as a postdoctoral research fellow at The University of Calgary, Canada. He was appointed to academic staff at The University of Newcastle in 2001 and has continued in this role since that time. His research interests include the structural behaviour, assessment and design of unreinforced and reinforced masonry as well as the strengthening / retrofit of existing masonry structures.

Professor Masia currently serves on Standards Australia Committee BD-004 Masonry Structures (since 2010) and BD-006 – Structural Loading (since 2014). He is a member of Engineers Australia and the International Masonry Society and an Editorial Board Member for International Journal of Masonry Research and Innovation.

Prof. Claudio Modena
(Italy)
The University of Padova



Title: RECENT ADVANCES OF ITALIAN RECOMMENDATIONS AND STANDARDS ON STRUCTURAL SAFETY OF EXISTING MASONRY STRUCTURES

ABSTRACT

The continued use of the huge stock of existing buildings that makes the everyday life possible in a country like Italy requires that not only continuum research efforts are made to set up reliable and specific methodologies and technologies to conduct controls and investigations regarding their structural efficiency and to execute adequate maintenance plans and, when necessary, repair and strengthening interventions, but also indispensable adjustments of the principles of the structural safety and of the ways how it is quantified.

Clear traces of what above can be found in the recent updating of the Italian national structural codes where particular importance is assumed by some innovations regarding structural safety issues.

The very critical issue is that the general recognized context of limited resources really available to make systematic interventions aimed to improve the structural safety of existing structures obliges to find a right balance between “structural safety” and “sustainability”, as clearly stated in the very important international standard ISO 13 822 Bases for design of Structures – Assessment of existing structures.

In this respect major results are obtained on one side limiting as much as possible the effects of “overdesign” of structural interventions that can be connected to the use of consolidated, necessarily “simplified”; procedures in use for verifying the structural safety of new structures and, on the other side, maximizing the effects, measured in terms of “risks reductions”, connected to the use of the effectively available resources to execute repair and strengthening interventions.

From the designer’s operative point of view a particular importance is assumed in this context by the so called “knowledge phase”, i.e. a deep, reliable knowledge of which are the real capacities of an existing structure to resist any type of possible action.

In the paper the most relevant of the above mentioned innovations are synthetically presented making particular reference to existing masonry structures.

BIO

Claudio Modena is Emeritus Professor at the University of Padova, Italy, where he graduated in 1970. He has a several years experience of research work as participant and responsible for the University of Padova Research Unit at international level within the frameworks programs of the EU, and at national level in several research projects founded and co-founded by the Ministry of Education, University and Research (MIUR, ex MURST) and other Ministries, by the National Research Council (CNR), by the National Group for Earthquake Defence (CNR-GNDT: Experimentation Work Group and Vulnerability Working Group), by the Italian Civil Protection Agency, by the ReLUIS University Consortium and by private industrial partners.

He maintained a balance between academic and practical experience, combining with mutual benefit both research work and technical consulting.

His fields of interest regarding masonry constructions include on-site investigation techniques for the structural evaluation of historic masonry constructions, experimental evaluation of the effectiveness and mechanical characterization of traditional and innovative (and combination of the two) materials and techniques currently used or newly proposed by industrial partners for repairing/strengthening existing masonry structures, development, improvement and extensive application of combined (simplified-complex) methods for the evaluation of seismic vulnerability of existing single historic building and bridge and historic building and bridge stock and for the optimal allocation of resources for setting up mitigation plans, management of post earthquake safeguard of historic centers stricken by earthquake, with specific reference to the earthquakes occurred in two Italian Regions (Abruzzo, April 9th 2009 and Emilia, May 2012), within the activity of the special authorities in charge for the conservation and reconstruction of historic centers damaged by the earthquakes.

He served and is still serving as member of various national and international research and standardization bodies: at national level at the Ministry of Cultural Heritage and at the Ministry of Public Works, and at the National Civil Protection Agency as a member of the National Extreme Risk Committee – Seismic Risk Sector.

Prof. Paulo Lourenço
(Portugal)
The University of Minho



Title: DESIGN OF MASONRY STRUCTURES (GENERAL RULES): HIGHLIGHTS OF THE NEW EUROPEAN MASONRY CODE

ABSTRACT

Despite the wide use of masonry buildings in Europe, existing rules for its structural design remains very scattered and lacking in clarity and understandability. Furthermore, since the last version of Eurocode 6 – Part 1-1 (2005), many research on the structural behaviour of masonry has been developed, in way that the specifications in the code need to be updated. A major challenge in developing design codes is indeed the conversion of research results to practical rules, according to a given design philosophy. Moreover, the subject of standardization needs to receive more attention and even be taken as a research topic. Such a lack may also raise an issue of understandability, because many of the design rules that are put into the codes are provided to the practitioner without a clear background. The new version of the European masonry code was developed as a compromise between the complexity of research results, the pragmatism of practical experience and the practitioner’s capabilities.

The new code should also contribute to make masonry more competitive, because only in this way it has the force to move trends and contribute for the regulation of the building sector. Following the CEN Mandate M/515, different subtasks were identified to be addressed in the new version of Eurocode 6 – Part 1-1, aimed to improve general aspects amongst the Eurocodes (e.g. reduction in NDPs and enhanced ease of use) and specific issues of masonry design (e.g. material properties and rules for reinforced masonry). There is still a long way to put the European codes in line with more recent design philosophies, like risk- and resilience-based design. Nevertheless, a significant evolution of Eurocode 6 – Part 1-1 code was achieved. At the current stage, this work is intended to give an overview of the European design standards, to look at international codes as a benchmark of masonry design, and to present the main developments in the new version of the European masonry code. A discussion is also made on needs and ways for further improvement of the standard, in terms of code philosophy, research lines and technical aspects.

BIO

Paulo B. LOURENÇO is Full Professor at the Department of Civil Engineering, University of Minho, Guimarães, Portugal since 2006. He received his degree in Civil Engineering at University of Porto, Portugal in 1990 and his PhD in Civil Engineering at Delft University of Technology, the Netherlands in 1996. He has been the Co-Head of the Institute in Sustainability and Innovation in Structural Engineering since 2007 and the Co-Head of the Institute for Bio-Sustainability since 2013. He is experienced in the fields of non-destructive testing, advanced experimental and numerical techniques, innovative repair and strengthening techniques, and earthquake engineering. He is specialist in structural conservation and forensic engineering, with work on more than one hundred monuments and existing buildings, including 7 UNESCO World Heritage sites. He is also a structural masonry expert, responsible for R&D projects with the clay brick, concrete block and lightweight concrete block masonry and mortar industry. He has been a consultant on innovative masonry structures using confined and reinforced masonry, and on masonry infills. He has been the leader of the Project Team responsible for the revision of Part 1 of the European code for masonry (EN 1996-1-1). He is the coordinator of the Advanced Masters on Structural Analysis of Monuments and Historical Constructions (SAHC) since 2007, with alumni from 70 countries and Europa Nostra Award in 2017. He is co-editor of the International Journal of Architectural Heritage and co-advisor of the Conference Series on Structural Analysis of Historical Constructions. He has supervised more than 50 PhD theses and coordinate multiple national and international research projects. He has been just awarded an Advanced ERC Grant of 3.0 M€ to develop an integrated seismic assessment approach for heritage buildings.

Prof. Mehrdad Hejazi
(Iran)
The University of Isfahan



Title: PERSIAN ADOBE HERITAGE: CONSTRUCTION TECHNOLOGY, CHARACTERISATION AND PROTECTION

ABSTRACT

The advantage of earthen structures is that their construction material is sustainable and has little impact on the environment. Building with earth expends little or none of earth’s finite resources, such as fossil fuels. Their embodied costs are low such as cost of creating, storing, distributing, using, and disposing. In hot-dry climates the high thermal mass of earth houses can render them substantially more energy-efficient than stick-built ones. However, earthen buildings have some disadvantages. They do not span open spaces or window and door openings very well, so they tend to crack near windows and doors that have inadequate wooden lintels. In the case of any failure in the roof, moisture can seep in and quickly erode the walls.

The availability of clay in Persia promoted the use of amorphous mud and later sun-dried moulded mud in the sixth millennium B.C. Archaeological surveys show the usage of earth and mud brick in houses from the fourth millennium B.C. Adobe buildings are still used in different parts of Iran, in particular in hot-arid areas. Adobe buildings include houses, bazaars, caravanserais, mosques, cisterns, icehouses, etc. The number of existing adobe buildings is more than that of brick, stone and wooden ones in the country. Hence, Persian adobe heritage is an important part of Persian architecture.

In this paper, a broad overview on Persian adobe heritage is carried out. It describes the construction technology of traditional adobe structures, the method of adobe making in Iran, adobe building with adobe roofs and with wooden roofs, adobe deterioration, repair and maintenance, construction detailing to resist earthquake, non-mechanical and mechanical characterisation of adobe, comparison between traditional and new adobes in Iran.

BIO

Mehrdad Hejazi is a Professor of Traditional Structures in the Faculty of Civil Engineering, University of Isfahan, Isfahan, Iran. He is an expert member of ICOMOS-ISCARSAH, and the chief advisor to Iranian Cultural Heritage Organisation. He is the first scholar who has investigated Persian architecture from a structural engineering view point and has published six books and more than 30 journal papers and 110 conference papers. He is an expert in the structural restoration of Persian historical buildings made of adobe and brick masonry. He has been the director of structural restoration of a number of National and World Heritage Sites in Iran.

Prof. Marco Corradi
(Italy)
Northumbria University



Title: A NEW METHOD FOR OUT-OF-PLANE REINFORCEMENT OF MASONRY WALLS USING HIGH STRENGTH STEEL STRAND

ABSTRACT

The use of new materials and methods in earthquake engineering offers alternative solutions to structural problems compared to traditional construction materials. Composite materials and metals for example have high strength to weight ratios, which can be especially beneficial where dead load or material handling considerations govern a design. However, the out-of-plane collapse of wall panels is not easy to prevent as its occurrence during an earthquake often depends on the geometrical characteristics (often known as geometrical vulnerabilities) of the masonry building. To determine the load at which wall panels of a masonry building overturn and collapse during seismic events using the simple method of the equilibrium of moments and taking into consideration the type of masonry, the single most important parameters are the boundary conditions of the wall-to-wall and wall-to-floor, which are easy to define but difficult to determine. Examples are given of the various out-of-plane mechanisms, that were observed in Italy after the 2009 and 2016 earthquakes, and the validity of the proposed method of analysis is checked. This paper presents a detailed discussion of the mechanisms of collapse, and shows that the initiation of overturning is not affected by the mechanical characteristics of the masonry, despite being loaded primarily in shear and compression. This paper also presents the novel retrofitting methods, available on the construction market, used to prevent the out-of-plane mechanisms of the wall panels during an earthquake through the application of high-strength steel wires, transversal connectors or the bonding of FRP materials.

BIO

Marco Corradi is actually an Aggregate Professor in Structural Mechanics at Perugia University, Italy. From 2013 to 2017, Marco Corradi served as Associate Professor at Northumbria University, Newcastle upon Tyne, UK. With an internationally recognised research profile in the field of structural analysis and retrofitting of historic masonry and timber constructions, he has been invited as a guest speaker at numerous research seminars in universities across Europe and USA. In addition, he is an editor of Construction and Building Materials (Elsevier) and sits in numerous editorial boards of scientific engineering journals. He is author of 214 articles and 4 books.

Prof. Stefano De Santis
(Italy)
The Roma Tre University



Title: UNCONVENTIONAL MEASUREMENT TECHNIQUES IN EXPERIMENTAL TESTING ON MASONRY

ABSTRACT

The lecture will provide an overview on the experience gained on the use of unconventional measurement techniques for the investigation of masonry either in the laboratory and in the field. The considered methods include Digital Image Correlation (DIC), passive 3D motion capture systems (3DVision), and acoustic emission (AE) monitoring.

Digital Image Correlation (DIC) was used, in combination with displacement and strain transducers, for the mechanical characterization of composite materials for structural rehabilitation, providing information on displacement and strains in tensile tests, on the strain field at the composite-to-substrate interface in shear bond tests, and on crack pattern in tests on mortar-based composites. DIC was also applied to laboratory tests on full-scale vault specimens, provided with buttresses and fill, to measure deflections and investigate arch-fill interaction. A passive 3D motion capture system was used to record the displacements of a large number of measurement points on full-scale specimens tested on the shake table within two research projects devoted to the seismic retrofitting with innovative technologies. Data were used to integrate measurements provided by displacement transducers and accelerometers, to derive information of the development and opening of cracks, and for experimental/operational modal analyses. The acoustic emission (AE) monitoring technique was used to investigate the fatigue deterioration process of small scale samples of brick masonry in the laboratory and for the condition assessment of masonry arch bridges under traffic loads, before and after the bridges underwent retrofitting.

Unconventional techniques can provide a large number of data with relatively simple procedures. Some of them are even easy to implement in the laboratory and, all things considered, are cost efficient. Their application, however, needs careful setup preparation, good knowledge of fundamental operation principles, and critical analysis of results. The main issues to be tackled include: (i) what useful information can be derived by these unconventional techniques, that would be unavailable otherwise? (ii) To what extent, or under what conditions, detected measurements reliable? (iii) How can these measurements be used to validate or integrate data recorded by traditional devices? These and other issues will be critically reviewed in order to promote discussion and orient future research initiatives.

BIO

Stefano De Santis is assistant professor at the Department of Engineering of Roma Tre University, where he got his BSc, MSc and PhD in Civil Engineering. Before getting his current position, he was a post-doc research assistant at the University of the West of England (UWE) at Bristol, UK (2012) and at Roma Tre University (2013-2017).

Stefano’s scientific interests include laboratory and field testing of materials and structures under static and dynamic/seismic loading, strengthening with composites, seismic assessment of existing constructions including bridges and architectural heritage, analytical/numerical modelling, testing methods and acceptance criteria for composite materials, innovative measurement techniques for laboratory testing and structural health monitoring.

On these topics, Stefano coordinated scientific activities involving research and industrial partners, has been visiting researcher at the University of Miami (2016) and at the University of Sheffield (2017), and is author of about 80 scientific publications. He is (or has recently been) involved in International Research Projects and is member of Technical Committees, including the RILEM TC-IMC, the RILEM TC 250-CSM, the RILEM TC 223-MSC, the ASTM D30 Committee, the COST Action TU1207, and the UIC Research Group on Masonry Arch Bridges. Stefano is member of national and international standardization boards, including the ACI 549-0L Committee “Design and Construction of Externally Bonded Fabric Reinforced Cementitious Matrix (FRCM) and Steel Reinforced Grout (SRG) Systems for Repair and Strengthening Masonry Structures”.

Prof. Bahman Ghiassi
(United Kingdom)
The University of Nottingham



Title: BOND BEHAVIOUR IN LIME-BASED TEXTILE REINFORCED MORTARS

ABSTRACT

Application of textile-reinforced mortar (TRM) composites for strengthening of existing structures or for production of new thin structural elements has been receiving a growing attention. TRMs are made of continuous textile fibres embedded in an inorganic matrix forming a composite material. The large variety of available fabric (glass, steel, basalt, PBO, etc.) and mortar types (cement-based, lime-based, etc.) leads to a wide range of mechanical properties making these composites suitable for fit-for-purpose design applications. Due to mechanical and hygrothermal compatibility issues, lime-based TRMs are the preferred choice for application to existing masonry and historical structures. Meanwhile, cement-based TRMs are usually employed for application to existing concrete or new masonry structures.

The main characteristic behaviour of these composites is the tension stiffening response and distributed cracking under tensile loads which are highly influenced by the fabric-to-mortar bond behaviour. Fundamental understanding of this mechanism and parameters affecting that are therefore of critical importance of designing TRM composites with desired properties.

This talk will cover the most recent findings on this topic. The role of different parameters on the bond behaviour in these composites will be presented followed by discussion of the main challenges and open issues.

BIO

Dr. Bahman Ghiassi is a lecturer (Assistant Professor) of Structural Engineering in the Faculty of Engineering of the University of Nottingham. He obtained his PhD from University of Minho in 2013. after which he was an individual fellowship postdoctoral research (funded by Portuguese scientific foundation) for 2.5 years and a Marie Curie Individual Fellowship postdoctoral researcher at Technical University of Delft for 2 years. He is expert in experimental testing and numerical modeling of the mechanics and durability of construction materials and structures and has received the RILEM’s Gustavo Collonetti medal in 2019 for his outstanding contribution to the field of construction materials and structures. He is also in the editorial board of International Journal of Masonry Research and Innovation, ASCE journal of Composites for Construction and open access journal of Materials.

Prof. Catherine (Corina) G. Papanicolaou
(Greece)
Department of Civil Engineering at the University of Patras



Title: PERFORMANCE OF TRM-TO-MASONRY JOINTS AFTER EXPOSURE TO ELEVATED TEMPERATURES

ABSTRACT

During the past fifteen years and for a number of well-documented reasons Textile Reinforced Mortar (TRM) systems have been gaining ground as a means of strengthening deteriorated, damaged or seismically deficient masonry structures. As for any new material, the bulk of experimental investigations have focused on the mechanical response of TRMs (both as standalone materials and in combination with different types of substrates) under normal service conditions. With the relevant learning curve reaching a plateau the interest of the academia is turning to durability-related aspects and extreme ex-posure scenarios. Although publications in the field are growing in number, the behavior of these materials under elevated/high temperatures and fire conditions is far from being exhaustively investigated and understood. This paper aims at systemizing the existing knowledge on the mechanical performance of TRM-to-masonry residual bond characteris-tics as a function of the exposure temperature of the joints.

BIO

Catherine (Corina) G. Papanicolaou is an Assistant Professor in the Department of Civil Engineering at the University of Patras and the technical responsible of the Fire Testing Facility (part of the Structural Materials Lab, civil Engineering Dept.). Her main research interests are focused on experimental mechanics of structural materials (with emphasis on innovative concrete materials and textile-based cementitious composites) and on the optimum design and testing of advanced prefabrication systems. She is/has been a member of the following Technical Committees: TRC/fib Task Group TRC (RILEM TC/fib TG TRC); TC CSM – “Composites for sustainable strengthening of masonry”; TC TDT – “Test methods and design of textile reinforced concrete”, TC MSC – “Masonry Strengthening with composite Materials” and since April 2019 she co-chairs the “TC IMC – “Durability of Inorganic Matrix Composites used for Strengthening of Masonry Constructions”.

Prof. Theodoros Rousakis
(Greece)
Democritus University of Thrace



Title: BRICK WALLS INTERVENTIONS WITH FRPU OR PUFJ AND OF RC COLUMNS WITH FR IN BRICK-INFILLED RC STRUCTURES WITH THE USE OF PUSHOVER BEAM-COLUMN ELEMENT ANALYSIS AND PSEUDO-DYNAMIC 3D FINITE ELEMENT ANALYSIS

ABSTRACT

This analytical study presents the effects of the strength and position of typical brick wall infills on the behavior of typical low rise deficient RC structure. The RC columns were retrofitted with different kinds of FRPs or Fiber Rope (FR) confinement. Pushover inelastic analyses were performed with SeismoStruct utilizing advanced beam-column elements and inelastic brick infill elements retrofitted with innovative Fiber Reinforced Polyurethane (FRPU). Past and recent pseudostatic and dynamic experiments have validated the increased displacement ductility brick walls retrofitted with FRPU and further strengthen the reliability of the performed analyses. The conclusions of this analytical study suggest that infill wall retrofit with FRPU may enable designers for alternative, more efficient interventions to meet contemporary code requirements. Suitable dynamic 3-dimensional Finite Element Modeling of RC and infills are presented to help advance innovative retrofit design for desirable in- and out-of-plane performance of RC frame – brick infill systems.

BIO

Theodoros Rousakis is an Assistant Professor of Repair and Strengthening of Concrete Members with Composites, at RC and Seismic Resistant Structures Lab, CE Departm., Democritus University of Thrace (DUTh, Greece). He teaches RC, Reinforced and Prestressed Concrete Bridges, Masonry Structures, Assessment and Retrofit of Structures, Design of Engineering Structures with Computational Methods, Strengthening and Repair with Advanced Composites and Hybrid Techniques for Resilience Upgrade of RC Structures Using FE Software etc. His research interests include 3d FE modelling of FRP retrofitted RC members and masonry; experiments, analyses and design considering seismic loading, fatigue loading, steel corrosion; resilient composite rope strengthening and flexible joints for infilled framed structures. He has published 120 journal and conference papers and book chapters (scopus H index 22 since 2002). He is member of fib TG5.1 and TG8.1 and of the Editorial or Advisory Board in 5 international journals and regular reviewer in more than 40 journals.

Prof. Tadeusz Tatara
(Poland)
The Cracow University of Technology



Title: MINING ACTIVITY IN POLAND: CHALLENGES

ABSTRACT

Mining shocks are the most intense phenomena generated by human activity and are called paraseismic sources. They accompany the mining of copper ore, hard and brown coal, gold, diamonds, non-ferrous metals and also originating from pile driving, driving sealed walls and car, train, tram traffic and subway traffic. These vibrations can cause not only significant damage to surface structures but also they can have negative influence on people occupied buildings. In Poland, mining tremors can usually only be observed in mining regions (the Upper Silesian Coalfield (USC), the Legnicko – Głogowski Copper District (LGCD)). Mining tremors are not subject to human control, and they are random events with respect to their time, place, and magnitude. There are many differences between earthquakes and mining tremors. The major differences are e.g. energy, intensive phase duration, peak ground accelerations (PGA), content of predominant frequencies, frequency of occurrence, depths of hypocentre. Mining-related vibrations stand out by having the greatest intensity of all forms of paraseismic vibrations.

My semi- keynote lecture deals with the most important problems we encounter when studying the impact of induced seismicity of environment and structures as follows:

1. analysis of experimentally obtained results in terms of the differences between the mine-induced vibrations described by the response spectra from the free-field near a given building and the simultaneously recorded vibrations in the building foundations
2. the impact of the type of building on the transmission of response spectra from the free-field vibrations to the building foundations
3. the usefulness of the approximate models of soil-structure interaction (SSI). The contribution presents original, simple, empirical models for the evaluation of the differences in the response spectra originating from free-field and building foundation vibrations in the mining region
4. assessment of the impact of mining – related vibrations on public buildings and industrial buildings, and assessment of their dynamic resistance using results of computer analyses
5. assessment of the impact of mining – related vibrations on buildings and on people staying in dwelling masonry buildings using: a) the RMS method according to British and Polish standards, b) new version of empirical-measurement scale GSIS-2017.

BIO

Professor Tatara’s research and scientific interests are related to issues concerning dynamics of building structures, with particular emphasis on experimental studies carried out on objects in - situ. The area of scientific interest includes issues related to, among others, the generation of paraseismic vibrations, their propagation and assessment of the impact of these vibrations on building structures. It concerns especially:

1. propagation of vibrations in the ground caused by various sources (e.g. surface blasting in quarries, rolling stock, road and tramways, underground mining),
2. dynamic interaction of the building - ground system caused by paraseismic type vibrations,
3. model and experimental analysis of dynamic characteristics and dynamic response of buildings erected using traditional (masonry) and industrialised methods (e.g. large block and large plate),
4. dynamic diagnostics, including the assessment of the harmfulness of the impact of vibrations transmitted from the ground on buildings and people living in them, with particular emphasis on the impact of shocks caused by mining operations.

Prof. Maria Rosa Valluzzi
Co-authors: E. Cescatti, L. Sbrogiò
(Italy)
The University of Padova



Title: VALIDATION OF DESIGN TOOLS FOR THE PREDICTION OF MECHANICAL BEHAVIOUR OF MASONRY ARCHES STRENGTHENED WITH INORGANIC MATRIX-BASED COMPOSITE SYSTEMS

ABSTRACT

Strengthening of masonry arches and vaults with composite materials has become a quite common strategy of intervention in seismic area. Composites (i.e., fibres made of carbon, glass, basalt, ..) provide a tensile contribution to masonry and allow for developing a pseudo-ductile behaviour, thus avoiding brittle collapse of curved structures.

In the last decades, fibre textiles embedded into inorganic matrix (known as FRCM - Fibre Reinforced Cementitious Mortar, TRM - Textile Reinforced Mortar, IMG - inorganic matrix grid; FRCM will be used in the following to identify all these systems) have been increasingly applied to existing masonry buildings as alternative to the first generation of composites, i.e. FRP (Fibre Reinforced Polymer). This is mainly due to the higher compatibility (including air-permeability) of inorganic matrix than epoxy with respect to the present materials.

Nowadays, several experimental works provide a significant dataset to characterize and interpret the mechanical behaviour under various strengthening configurations on different types of arches and vaults. These studies contributed to the definition of design and assessment approaches, which have been only recently agreed in the scientific community for FRCM (e.g., ACI-Rilem recommendations 2019?).Therefore, at present, design tools need to be validated and/or upgraded according to the current scientific state-of-the-art.

In the paper, based on the experimental results obtained in over 25 literature cases, a comparative study among different conditions of masonry arches strengthened with FRCM systems is proposed. The main parameters affecting the structural behaviour of components in both plain and strengthened conditions are identified, and their influence in analytical procedures implemented in common software able to predict failure modes and bearing capacity (either limit state or rigid block analyses-based) are discussed. The pro and cons, as well as the strategies for representing at best the experimental outcomes are also presented.

BIO

Maria Rosa Valluzzi is Associate Professor at the Dept of Cultural Heritage of the University of Padova. Structural Engineer, Ph.D. on ‘Design, control and rehabilitation of traditional and innovative structures’, she teaches on MSc and doctorate courses since 2000. Research topics concern the experimental study and modeling of the mechanical behavior of existing structures, with focus on knowledge procedures, intervention techniques, and seismic vulnerability of masonry buildings, historical city centers and archeological sites. Active member of several international technical committees and research groups, she is author of more than 350 publications. Awarded by Rilem with the ‘Robert l’Hermite’ medal in 2005 and honored as fellow in 2015.