Fragility functions for tall URM buildings around early 20th century in Lisbon. Part 2: Application to different classes of buildings

This article describes the application of the procedure for the derivation of fragility functions presented in the companion article entitled Fragility functions for tall URM buildings around early 20th century in Lisbon. Part 1: methodology and application at building level. The procedure, based on the execution of non-linear analyses, was developed to be applied to unreinforced masonry buildings considering both the in-plane and out-of-plane response. Different sources of uncertainty, both epistemic and aleatory, affecting the behaviour of these unreinforced masonry buildings are discussed and treated with a probabilistic procedure. The fragility curves determined for the different classes of buildings are compared and then combined to define the final fragility curves for these unreinforced masonry buildings. The results put in evidence the high seismic vulnerability of these buildings and the urgent need for the structural intervention and for the design of retrofitting measures in order to reduce potential losses due to future earthquakes.The first author would like to acknowledge the financial support of Fundacao para a Ciencia e a Tecnologia (FCT, Ministerio da Educacao e Ciencia, Portugal) through the scholarship PD/BD/106076/2015 through the FCT Doctoral Program: Analysis and Mitigation of Risks in Infrastructures, INFRARISK (http://infrarisk.tecnico.ulisboa.pt)

Numerical investigation of the in-plane seismic performance of unstrengthened and TRM-strengthened rammed earth walls

The large availability of raw earth around the World led to its extensive use as a building material through history. Thus, earthen materials integrate several historical monuments, but their main use was to build living and working environments for billions of people. On the other hand, past earthquakes revealed their inadequate seismic behavior, which is a matter of concern as a significant percentage of earthen buildings are located in regions with medium to high seismic hazard. Nevertheless, their seismic behavior and the development of efficient strengthening solutions are topics that are not yet sufficiently investigated in the literature. In this context, this study investigates numerically the in-plane seismic behavior of a rammed earth component by means of advanced nonlinear finite element modeling, which included performing nonlinear static (pushover) and nonlinear dynamic analyses. Moreover, the strengthening effectiveness of a low-cost textile-reinforced mortar on such component was also evaluated. The strengthening was observed to increase the load and displacement capacities, to preserve the integrity for higher lateral load levels and to postpone failure without adding significant mass to the system. Furthermore, the pushover analysis was shown to predict reliably the capacities of the models with respect to the incremental dynamic analysis.This work was financed by FEDER funds through the Competitively Factors Operational Programme (COMPETE) and by national funds through the Foundation for Science and Technology (FCT) within the scope of projects POCI-01-0145-FEDER-016737 (PTDC/ECM-EST/2777/2014) and POCI-01-0145-FEDER-007633. The support from grant SFRH/BPD/97082/2013 is also acknowledged

Influence of adding phase change materials on the physical and mechanical properties of cement mortars

During the last years several studies of construction materials with incorporation of encapsulated phase change material (PCM) have been published. However, the utilization of non-encapsulated PCM is one of the main gaps. The main objective of this work was the study of physical and mechanical properties of cement mortars with incorporation of non-encapsulated PCM. It was possible to conclude that the utilization of non-encapsulated phase change materials can be seen as a good and more economical solution for the energy efficiency of the buildings, without prejudice of the properties.The authors acknowledge the Portuguese Foundation for Science and Technology (FCT) for the financial support of PhD scholarship SFRH/BD/95611/2013

Impact of repairs on embodied carbon dioxide expenditure for a reinforced-concrete quay

Studies on structural repair using life-cycle analysis are still lacking the environmental impact of repair actions. This research work shows that the choice of the best repair option for reinforced-concrete structures is a function of long-term environmental impact, considering the longevity of maintenance intervention and embodied carbon dioxide expenditure. The purpose of this work was to assess the lifetime of a quay superstructure exposed to an aggressive marine microenvironment by using a probabilistic performance-based approach and then to select the best repair option for its reinforced-concrete structures. The comparison is made for reinforced-concrete service life using three different concrete types and two different corrosion inhibitors. Longevity and embodied carbon dioxide were predicted for the expected number of repair actions per 100 years. It is shown that concretes may have a higher impact at the outset, although they result in a much lower impact across the service life of the structure