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Abstract One of the biggest issues in civil engineering is the poor performance of concrete repairs. In fact, in Europe only 50% of concrete structures restorations are estimated to be successful, even though rehabilitation costs account for about half of the yearly construction budgets. This research aims at investigating a potential green approach to the sustainability of rehabilitation solutions for infrastructures. Following a simplified analysis of C02 emissions, intervention costs, social aspects, structural performances and other variables considered relevant to the scope, possible rehabilitation techniques are compared and ranked. The following four different options have therefore been designed to be applied to an actual column of the Brabau Bridge in Sardinia (Italy): i. complete removal and replacement of the column, ii. replacement of the damaged longitudinal rebars by machined bars and ultra-high performance fibre-reinforced concrete (UHPFRC) strengthening, iii. longitudinal and transverse fiber reinforced polymers (FRP) wrapping, iv. concrete jacketing. A methodological and procedural strategy is established through multi-criteria analysis that will allow future developments to assess the whole Life Cycle Assessment of the maintenance work.

Well-known methods for seismic performance assessment, such as incremental dynamic analysis (IDA), multi-stripes analysis (MSA) and the cloud method, involve nonlinear response time-history analyses to characterize the relationship between the chosen damage measure versus intensity measure. Over the past two decades, many authors have proposed simplified procedures or nonlinear static approaches to develop fragility. In these procedures, the capacity of the system is evaluated by nonlinear static procedures (i.e., the capacity spectrum method (CSM), the N2 method, modal pushover analysis (MPA)) and the demand is derived by response spectra. In addition to the familiar ones, incremental modal pushover analysis (IMPA) is a novel nonlinear static procedure proposed in recent years, and it is used in this research to present an IM-based fragility estimation. The accuracy and effectiveness of different methods to assess vulnerability are investigated by comparing fragility curves derived by MPA-based cloud analysis, IMPA and cloud analysis against IDA. The comparison gives valuable insights on the influence of scaling on different sets of records; however, a more extended validation is needed to confirm the obtained results and draw more general conclusions. Results arise from two relatively small bins of record motions differing by ranges of Joyner-Boore distance and scattered in a range of magnitude are presented.

Road network functionality after an earthquake is a crucial aspect for an already struck community. In particular, bridges are susceptible to earthquake-induced damages and to lengthy restoration works. This may lead to severe and unexpected disruption of traffic. In this paper, a model for the assessment of the seismic resilience of a road network is presented. The proposed model permits us to evaluate the earthquake-induced perturbations to the functionality of a network in terms of transportation capacities, traffic congestion, and travel times due to bridge damages and subsequent restoration interventions. The evolution over time of the functionality of the network is studied by means of a multi-stage approach describing the evolution of the situation in terms of reducing the normal pre-earthquakes transportation capacities. The methodology has been illustrated with reference to a hypothetical case study, a road network composed of 14 nodes and 31 links.

This paper discusses the seismic behavior of reinforced concrete (RC) bridge structures, focusing on the shear−flexure interaction phenomena. The assessment of reinforced concrete bridges under seismic action needs the ability to model the effective non-linear response in order to identify the relevant failure modes of the structure. Existing RC bridges have been conceived according to old engineering practices and codes, lacking the implementation of capacity design principles, and therefore can exhibit premature shear failures with a reduction of available strength and ductility. In particular, recent studies have shown that the shear strength can decrease with the increase of flexural damage after the development of plastic hinges and, in some cases, this can cause unexpected shear failures in the plastic branch with a consequent reduction of ductility. The aim of the research is to implement those phenomena in a finite-element analysis. The proposed model consists of a flexure fiber element coupled with a shear and a rotational slip spring. The model has been implemented in the OpenSEES framework and calibrated against experimental data, showing a good ability to capture the overall response.

The mandibular third molar has variable root morphology. Moreover, it quite often presents eruption disturbances, such as partial or total impaction. The mandibular third molar lies in the vicinity of the mandibular canal and its neurovascular content. The mandibular canal has often close or tangent relationship with the root apices and even with the crown of this tooth, in the case of its deep impactions. Such aspects become favourable factors for neurovascular complications following various radical or conservative treatments performed on these teeth, taking into account the fact that these therapeutic procedures are frequent in dentistry. The current study presents the consequent complications of endodontic and surgical treatments at the level of the mandibular third molar as well as their clinical and medico-legal implications, aiming at focusing dentists’ attention on correct diagnosis and management.

The maxillary artery (MA) is the main vascular source for the maxillary and mandibular tooth-gum-alveolar bone units, running adjacent to the lateral pterygoid muscle. The purpose of this review is to bring evidence-based knowledge on the topography and trajectory variations of the MA in the infratemporal region, with emphasis on clinically relevant findings. The MA is the most important vascular element in the infratemporal region due to its relationships with the nerve branches encountered at this level. The variability of the topographical relationships of the MA within the infratemporal region can lead to complications in oral and maxillofacial surgery. Knowledge of the anatomical variations of the MA contributes to the prevention and reduction of a wide variety of surgical complications

In the light of the current COVID-19 pandemic, being considered a present challenge for public health, the main purpose of this work is to analyze the vulnerability to stress of a sample of nursing students in Romania considering their status on labour market (employed students in the medical system and non-employed students) before and during the COVID-19 pandemic. Employed students were more vulnerable to stress comparing to non-employed ones during the pandemic. In addition to this, the nursing students working in the medical system experienced medium vulnerability to stress during the pandemic comparing to those working before the pandemic who experienced a low vulnerability to stress. Excepting the non-employed students before the pandemic, the females were more vulnerable to stress comparing to the males in the sample and the students living in the country experienced a higher level of stress comparing to those living in the urban area. During the pandemic, most of the employed nursing students expressed their fear of getting infected with COVID-19, this representing the most stressful factor for them, while most of them mentioned the self-control as being the most proper strategy for them to cope with stress. These empirical findings have practical implications for stress control among present and future nurses, for management of medical units and for higher education nursing.

Nursing has always been a stressful job affecting the physical and mental health of the nurses, but the new medical context of the COVID-19 pandemic has enhanced this issue. The objective of this paper is to study differences between non-employed and employed nursing students in the medical system of Romania before and during the epidemic using matching methods and a sample of 526 nursing students. Stressors and strategies for coping with stress were also identified during the pandemic. The results indicated that employed students were more vulnerable to stress compared to non-employed ones before and during the pandemic. Females registered significantly higher stress scores compared to males in the period of the epidemic. The analysis of the overall sample suggested that gender and environment were significant stress factors during the pandemic, but living conditions were not relevant. The most effective coping strategies against stress for nurses during the COVID-19 crisis were based on self-control and the spiritual dimension, unlike the previous period when other colleagues’ support helped most nurses to overcome difficult working conditions. The implications of this study might help medical management in ensuring a less stressful environment for nurses during the epidemic.