Seismic vulnerability of masonry heritage buildings in Malta

The structural behaviour of masonry heritage buildings in Malta subjected to seismic action is a major risk in conserving such buildings. This is because Malta lies on a seismic zone which was subjected to high intensity earthquakes in the past (Galea, 2007). Many of the existing masonry heritage buildings were subjected to major earthquakes of 1693, 1743 and 1856, with repairs ranging from minor repairs to partial rebuilding (Abela, 1969; Galea, 2007). The survival of such buildings does not determine the degree of seismic resistance to any future strong tremor. The study will explore the possibility to determine the seismic vulnerability of masonry heritage buildings using Applied Element Method (AEM), a numerical structural modelling. Since AEM was never used to determine seismic vulnerability of masonry heritage buildings in Malta, simple masonry heritage building typology is being analysed in this study.peer-reviewe

Proposal for the nomination of Lower Globigerina Limestone of the Maltese Islands as a "Global Heritage Stone Resource"

The Lower Globigerina Limestone of the Maltese Islands is here being proposed for nomination as a “Global Heritage Stone Resource”. This stone, continuously used for building and sculpture for 6000 years, is well suited to fit this global designation as it is not only of great local cultural, historic and economic importance, but it is also the building stone used in construction of the UNESCO, and hence internationally recognized, World Heritage city of Valletta, as well as the UNESCO-listed Prehistoric Megalithic Temples of the Maltese Islands. The stone was also exported to several European and North African countries especially in the early 20 th century. The entire range of archaeological remains and historic architecture which cover the Maltese Islands have been built in this stone, and encompass innumerable palaces and churches, including the fortified cities of Valletta, Mdina (the old capital of Malta), the Three Cities on the Grand Harbour and the Citadel of Gozo, as well as the vernacular architecture ubiquitous within the village cores all over the Islands. The soft limestone has also been widely used over the millennia for elaborate and extensive sculptural motifs. Practically the only natural resource of the Islands, it continues to be quarried today, and is used not only for new construction, but also for the regular restoration of Malta’s great and imposing architectural heritage, remaining thus an important pillar of the Maltese economy.peer-reviewe

Thermal performance of external renders applied to concrete blockwork

The aim of this study was to investigate and analyse different external renders, available locally, and to study how their use may enhance the overall thermal performance of local concrete blockwork. This study provides an insight into how the various types of renders available improve the U-value of a concrete block wall. Three main types of external renders were used as the basis of this study. Results demonstrate that the ‘glass fibre additive’ type of render helped to greatly improve the U-value of a bare concrete block wall. This enhanced U-value, however, is achieved using more expensive render systems. Thus, from this study, the energy conscious designer can assess how, with the help of specific external renders, a more energy efficient building could be achieved, or how an existing building’s thermal efficiency could be improved. There are three aspects of performance that inform the selection of an external finish, namely: Aesthetic quality (colour & texture); Cost effectiveness, as compared to other types of finishes; Resilience to adverse weather conditions, particularly thermal performance. This paper investigates the issues relating to thermal performance, but also highlights the cost associated with choosing alternative but similar renders.peer-reviewe

Georisks in the Mediterranean and their mitigation

An international scientific conference organised by the Seismic Monitoring and Research Unit, Department of Geoscience, Faculty of Science, Department of Civil and Structural Engineering and Department of Construction and Property Management, Faculty of the Built Environment, University of Malta.Part of the SIMIT project: Integrated civil protection system for the Italo-Maltese cross-border area. Italia-Malta Programme – Cohesion Policy 2007-2013This conference is one of the activities organised within the SIMIT strategic project (Integrated Cross-Border Italo-Maltese System of Civil Protection), Italia-Malta Operational Programme 2007 – 2013. SIMIT aims to establish a system of collaboration in Civil Protection procedures and data management between Sicilian and Maltese partners, so as to guarantee the safety and protection of the citizens and infrastructure of the cross-border area. It is led by the Department of Civil Protection of the Sicilian region, and has as other partners the Department of Civil Protection of Malta and the Universities of Palermo, Catania and Malta. SIMIT was launched in March 2013, and will come to a close in October 2015. Ever since the initial formulation of the project, it has been recognised that a state of national preparedness and correct strategies in the face of natural hazards cannot be truly effective without a sound scientific knowledge of the hazards and related risks. The University of Malta, together with colleagues from other Universities in the project, has been contributing mostly to the gathering and application of scientific knowledge, both in earthquake hazard as well as in building vulnerability. The issue of seismic hazard in the cross-border region has been identified as deserving foremost importance. South-East Sicily in particular has suffered on more than one occasion the effects of large devastating earthquakes. Malta, although fortunately more removed from the sources of such large earthquakes, has not been completely spared of their damaging effects. The drastic increase in the building density over recent decades has raised the level of awareness and concern of citizens and authorities about our vulnerability. These considerations have spurred scientists from the cross-border region to work together towards a deeper understanding of the underlying causes and nature of seismic and associated hazards, such as landslide and tsunami. The SIMIT project has provided us with the means of improving earthquake surveillance and analysis in the Sicily Channel and further afield in the Mediterranean, as well as with facilities to study the behaviour of our rocks and buildings during earthquake shaking. The role of the civil engineering community in this endeavour cannot be overstated, and this is reflected in the incorporation, from the beginning, of the civil engineering component in the SIMIT project. Constructing safer buildings is now accepted to be the major option towards human loss mitigation during strong earthquakes, and this project has provided us with a welcome opportunity for interaction between the two disciplines. Finally the role of the Civil Protection authorities must occupy a central position, as we recognize the importance of their prevention, coordination and intervention efforts, aided by the input of the scientific community. This conference brings together a diversity of geoscientists and engineers whose collaboration is the only way forward to tackling issues and strategies for risk mitigation. Moreover we welcome the contribution of participants from farther afield than the Central Mediterranean, so that their varied experience may enhance our efforts. We are proud to host the conference in the historic city of Valletta, in the heart of the Mediterranean, which also serves as a constant reminder of the responsibility of all regions to protect and conserve our collective heritage.peer-reviewe

The seventh national communication of Malta under the United Nations framework convention on climate change

This is the fourth time that Malta is submitting a National Communication under the United Nations Framework Convention on Climate Change (UNFCCC), following the submission of a First National Communication in 2004 and a Second National Communication in 2010. This is also the second time that Malta is submitting such a Communication since its accession to Annex I status under the Convention, the first two submissions having been made as a non-Annex I Party. Emission reduction or limitation commitments applicable to Malta Malta’s status under the Convention up to the time it applied for accession to Annex I, and with that accession being conditional to not taking on quantified emission limitation or reduction targets for the first commitment period of the Kyoto Protocol, meant that until 2012 Malta was not subject to an economy-wide greenhouse gas related obligation under the Protocol. This however did not mean that Malta had no obligations to limit or reduce emissions from anthropogenic activities taking place in the country. In line with, Malta will be contributing its fair share of the EU’s unconditional commitment under the Convention to reduce emissions by 20% below 1990 levels by 2020. This is in line with the target inscribed in the amendments to the Kyoto Protocol (the Doha Amendments), that will be jointly fulfilling the second commitment period with the other Union member states; therefore, emissions from the aforementioned power plants remain subject to compliance with EU Emissions Trading Scheme provisions, while the Effort-Sharing Decision target is the principal emissions mitigation obligation that the country has until 2020, for all other greenhouse gas emissions. The major point sources of greenhouse gas emissions in Malta, namely the electricity generation plants have been, since of 2005, subject to the EU Emissions Trading Scheme, whereby they are required to surrender allowances in respect of emissions of carbon dioxide. Emissions of greenhouse gases not covered by the EU Emissions Trading Scheme, are subject to an overall limit under the so-called Effort-Sharing Decision. Under this decision, Malta must limit such greenhouse gases to not more than 5% over emission levels in 2005, by 2020. The EU is already looking towards the longer-term future, with the 2030 climate and energy framework providing for a 40% domestic reduction target for 2030. Legislative implementation of this goal is currently under discussion at EU level.peer-reviewe

Approaches to industrial heritage: what works?

When heritage authorities select monuments for “preservation”, as part of the culture of a society, this selection is often solely based on stylistic and historical grounds, rather than on technological, constructional or material criteria. It is in reaction to this limited view of “preservable” heritage, that the discipline of “industrial heritage” or “industrial archaeology” has become so topical in recent years. It is also as a result of what can best be defined as “academic neglect”, that the discipline has thrived mostly as a result of the passion of a few “amateur” individuals.peer-reviewe

The protective shelters at Hagar Qim and Mnajdra : impacts, dilemmas and values

Engineering technology has opened up many new possibilities for the protection of cultural heritage, which have brought with them the attendant dilemmas on the risks and impacts posed by those possibilities themselves. The case of the protective shelters over ĦaġarQim and Mnajdra, completed in 2009,is examined here in order to explore some of the dilemmas that were faced from inception to completion, the values that informed the decisions that were taken, and some reflections two years after their completion. Apart from the benefits for the material conservation of the monuments, it is argued that their symbolic and aesthetic values may have been reinterpreted rather than degraded by the intervention.peer-reviewe

The development of a rapid empirical seismic vulnerability assessment methodology for contemporary load-bearing masonry buildings in the Maltese Islands

According to historical records, the last major earthquake reported to have caused extensive damage in the MalteseIslands dates back to 1693. It is not possible to assess the vulnerability of masonry structures to seismic action through post-earthquake damage assessments. Considering a return period of 475 years, the probability of occurrence of a major seismic event is quite high. This study is an attempt at addressing the issue of the seismic response of the building stock in Malta. It focuses on the typical contemporary load-bearing masonry building typology. This typology mainly consists of blocks of apartments including a semi-basement with no internal walls and, in most cases, roofed over by hollow core precast prestressed planks, and with around 4 overlying residential floors in addition to a penthouse level.peer-reviewe

Earthquake lessons : a simple journey into our planet and what it makes it shake

This book is part of the SIMIT project: Integrated civil protection system for the Italo-Maltese cross-border area. Specific topics regarding earthquakes is provided, particularly how earth movements are caused and safety precautions during seismic activity.peer-reviewe