Effect of buoyancy loads on the tsunami fragility of existing reinforced concrete frames including consideration of blow-out slabs.

Currently available performance-based methodologies for assessing the fragility of structures subjected to tsunami neglect the effects of tsunami-induced vertical loads due to internal buoyancy. This paper adopts a generalized methodology for the performance assessment of structures that integrates the effects of buoyancy loads on interior slabs during a tsunami inundation. The methodology is applied in the fragility assessment of three case-study frames (low, mid and high-rise), representative of existing masonry-infilled reinforced concrete (RC) buildings typical of Mediterranean region. The paper shows the effect of modelling buoyancy loads on damage evolution and fragility curves associated with different structural damage mechanisms for existing RC frames with breakaway infill walls including consideration of blow-out slabs. The outcomes attest that buoyancy loads affect the damage assessment of buildings during a tsunami, especially in the case of mid and high-rise structures with blow-out slabs. The rate of occurrence of slabs uplift failure increases with the number of stories of the building, indicating the need to account for such damage mechanism when assessing the performance of structures. It is also found that buoyancy loads slightly affect the fragility curves associated to other structural damage mechanisms for existing RC buildings commonly monitored for fragility assessment.

Simplified model for pre-code RC column exposed to fire followed by earthquake.

The behaviour of pre-code reinforced concrete (RC) columns in sequence of fire and earthquake is not well understood and can be critical in case of buildings which experienced fire and are either unrepaired or poorly repaired when exposed to an earthquake. This study proposes a framework on how to construct a simplified model to assess the post-fire cyclic behaviour of such columns. Emphasis is given to the development of simplified material models which can be used to describe the performance of the confined concrete, as its post-fire behaviour is not well studied. The model's performance is validated against the experimental results of a square, non-seismically designed RC column. Three scenarios are considered. The reference scenario, where the column is exposed only to cyclic loading. In the other two, the column is firstly exposed to an ISO-834 time-temperature curves in a furnace of 30 min and 90 min duration and after it cooled down, it is exposed to cyclic loading. The results showed that simplified material models can be used to capture the post-fire cyclic behaviour of an RC column, built without seismic design. It was also found that the confined model adopted played an important role after the peak strength is reached.

Prioritization of hazards for risk and resilience management through elicitation of expert judgement.

Risk assessment in communities or regions typically relies on the determination of hazard scenarios and an evaluation of their impact on local systems and structures. One of the challenges of risk assessment for infrastructure operators is how to identify the most critical scenarios that are likely to represent unacceptable risks to such assets in a given time frame. This study develops a novel approach for prioritizing hazards for the risk assessment of infrastructure. Central to the proposed methodology is an expert elicitation technique termed paired comparison which is based on a formal mathematical technique for quantifying the range and variance in the judgements of a group of stakeholders. The methodology is applied here to identify and rank natural and operational hazard scenarios that could cause serious disruption or have disastrous effects to the infrastructure in the transnational Øresund region over a period of 5 years. The application highlighted substantial divergences of views among the stakeholders on identifying a single 'most critical' natural or operational hazard scenario. Despite these differences, it was possible to flag up certain cases as critical among the natural hazard scenarios, and others among the operational hazards.

Full-scale cyclic testing of realistic reinforced-concrete beam-column joints.

The seismic performance of reinforced concrete (RC) structures are highly influence by the cyclic performance of the beam-column joints. The experimental seismic assessment of RC beam-column joints has been made essentially by cyclic tests performed on set-ups that do not totally simulate the real seismic loading and constrains conditions. A complex monitoring scheme is used to record the applied loads, reactions, joint distortion, strains on the reinforcement, lateral and axial displacements on the entire specimen, rotations and surface strains by using digital image correlation (DIC). The use of DIC is particularly important to record the strains on CFRP used to wrap the columns and beams. Based on the data recorded during the tests, it is possible compute moments; rotations and curvatures of the columns and beams; joint shear; dissipated energy by beams, columns and joint; yield displacement; ductility; peak-to-peak stiffness degradation; post-peak softening; and inter-cycle strength degradation. The innovative experimental set-up herein presented has the following advantages compared with others:•Lateral loading applied on the top of the superior column and not on the beams•Real scale specimens and the possibility of have transversal beams and slab•Dead loads on the beams and columns with two different axial loads.

Developmental Language Disorder: Early Predictors, Age for the Diagnosis, and Diagnostic Tools. A Scoping Review.

BACKGROUND: Developmental Language Disorder (DLD) is frequent in childhood and may have long-term sequelae. By employing an evidence-based approach, this scoping review aims at identifying (a) early predictors of DLD; (b) the optimal age range for the use of screening and diagnostic tools; (c) effective diagnostic tools in preschool children. METHODS: We considered systematic reviews, meta-analyses, and primary observational studies with control groups on predictive, sensitivity and specificity values of screening and diagnostic tools and psycholinguistic measures for the assessment of DLD in preschool children. We identified 37 studies, consisting of 10 systematic reviews and 27 primary studies. RESULTS: Delay in gesture production, receptive and/or expressive vocabulary, syntactic comprehension, or word combination up to 30 months emerged as early predictors of DLD, a family history of DLD appeared to be a major risk factor, and low socioeconomic status and environmental input were reported as risk factors with lower predictive power. Optimal time for screening is suggested between age 2 and 3, for diagnosis around age 4. Because of the high variability of sensitivity and specificity values, joint use of standardized and psycholinguistic measures is suggested to increase diagnostic accuracy. CONCLUSIONS: Monitoring risk situations and employing caregivers' reports, clinical assessment and multiple linguistic measures are fundamental for an early identification of DLD and timely interventions.

Efficacy of the Treatment of Developmental Language Disorder: A Systematic Review.

BACKGROUND: Language disorder is the most frequent developmental disorder in childhood and it has a significant negative impact on children's development. The goal of the present review was to systematically analyze the effectiveness of interventions in children with developmental language disorder (DLD) from an evidence-based perspective. METHODS: We considered systematic reviews, meta-analyses of randomized controlled trials (RCTs), control group cohort studies on any type of intervention aimed at improving children's skills in the phono-articulatory, phonological, semantic-lexical, and morpho-syntactic fields in preschool and primary school children (up to eight years of age) that were diagnosed with DLD. We identified 27 full-length studies, 26 RCT and one review. RESULTS: Early intensive intervention in three- and four-year-old children has a positive effect on phonological expressive and receptive skills and acquisitions are maintained in the medium term. Less evidence is available on the treatment of expressive vocabulary (and no evidence on receptive vocabulary). Intervention on morphological and syntactic skills has effective results on expressive (but not receptive) skills; however, a number of inconsistent results have also been reported. Only one study reports a positive effect of treatment on inferential narrative skills. Limited evidence is also available on the treatment of meta-phonological skills. More studies investigated the effectiveness of interventions on general language skills, which now appears as a promising area of investigation, even though results are not all consistent. CONCLUSIONS: The effectiveness of interventions over expressive and receptive phonological skills, morpho-syntactic skills, as well as inferential skills in narrative context underscores the importance that these trainings be implemented in children with DLD.

The Fix-it face-to-face intervention increases multihazard household preparedness cross-culturally.

Vulnerability to natural disasters is increasing globally1-3. In parallel, the responsibility for natural hazard preparedness has shifted to communities and individuals4. It is therefore crucial that households increase their preparedness, yet adoption of household preparedness measures continues to be low, even in high-risk regions5-8. In addition, few hazard-preparedness interventions have been evaluated longitudinally using observational measures. Therefore, we conducted a controlled intervention with a 12-month follow-up on adults in communities in the United States and Turkey that focused on improving household earthquake and fire preparedness. We show that this Fix-it intervention, involving evidence-based, face-to-face workshops, increased multihazard preparedness in both cultures longitudinally. Compared to baseline, the primary outcome-overall preparedness-increased significantly in the intervention groups, with more improvement in earthquake preparedness in the Turkish participants and more improvements in fire preparedness in the US participants. High baseline outcome expectancy and home ownership predicted overall preparedness change in both intervention groups longitudinally, implying that a sense of agency influences preparedness. An unintended consequence of observation is that it may increase preparedness, as even the control groups changed their behaviour. Therefore, observation of home preparatory behaviours by an external source may be a way to extend multihazard preparedness across a population.

Stigma in science: the case of earthquake prediction.

This paper explores how earthquake scientists conceptualise earthquake prediction, particularly given the conviction of six earthquake scientists for manslaughter (subsequently overturned) on 22 October 2012 for having given inappropriate advice to the public prior to the L'Aquila earthquake of 6 April 2009. In the first study of its kind, semi-structured interviews were conducted with 17 earthquake scientists and the transcribed interviews were analysed thematically. The scientists primarily denigrated earthquake prediction, showing strong emotive responses and distancing themselves from earthquake 'prediction' in favour of 'forecasting'. Earthquake prediction was regarded as impossible and harmful. The stigmatisation of the subject is discussed in the light of research on boundary work and stigma in science. The evaluation reveals how mitigation becomes the more favoured endeavour, creating a normative environment that disadvantages those who continue to pursue earthquake prediction research. Recommendations are made for communication with the public on earthquake risk, with a focus on how scientists portray uncertainty.

Stochastic coupled simulation of strong motion and tsunami for the 2011 Tohoku, Japan earthquake.

This study conducts coupled simulation of strong motion and tsunami using stochastically generated earthquake source models. It is focused upon the 2011 Tohoku, Japan earthquake. The ground motion time-histories are simulated using the multiple-event stochastic finite-fault method, which takes into account multiple local rupture processes in strong motion generation areas. For tsunami simulation, multiple realizations of wave profiles are generated by evaluating nonlinear shallow water equations with run-up. Key objectives of this research are: (i) to investigate the sensitivity of strong motion and tsunami hazard parameters to asperities and strong motion generation areas, and (ii) to quantify the spatial variability and dependency of strong motion and tsunami predictions due to common earthquake sources. The investigations provide valuable insights in understanding the temporal and spatial impact of cascading earthquake hazards. Importantly, the study also develops an integrated strong motion and tsunami simulator, which is capable of capturing earthquake source uncertainty. Such an advanced numerical tool is necessary for assessing the performance of buildings and infrastructure that are subjected to cascading earthquake-tsunami hazards.