Since the 1985 M 8.0 central Chile earthquake, national strong-motion seismic networks have recorded ten megathrust earthquakes with magnitudes greater than M 7.5 at the convergent margin, defined by the contact between the Nazca and South American plates. The analysis of these earthquake records have led to improved hazard analyses and design codes for conventional and seismically protected structures. Although strong-motion baseline correction is required for a meaningful interpretation of these records, correction methods have not been applied consistently in time. The inconsistencies between correction methods have been neglected in the practical use of these records in practice. Consequently, this work aims to provide a new strong-motion database for researchers and engineers, which has been processed by traceable and consistent data processing techniques. The record database comes from three uncorrected strong motion Chilean databases. All the records are corrected using a four-step novel methodology, which detects the P-wave arrival and introduces a baseline correction based on the reversible-jump Markov chain Monte Carlo method. The resulting strong motion database has more than 2000 events from 1985 to the date, and it is available to download at the Simulation Based Earthquake Risk and Resilience of Interdependent Systems and Networks (SIBER-RISK) project website.

ABSTRACTA new computational platform for seismic hazard assessment is presented. The platform, named SeismicHazard, allows characterizing the intensity, uncertainty, and likelihood of ground motions from subduction‐zone (shallow interface and intraslab) and crustal‐zone earthquakes, considering site‐specific as well as regional‐based assessments. The platform is developed as an object‐oriented MATLAB graphical user interface, and it features several state‐of‐the‐art capabilities for probabilistic and deterministic (scenario‐based) seismic hazard assessment. The platform integrates the latest developments in performance‐based earthquake engineering for seismic hazard assessment, including seismic zonation models, ground‐motion models (GMMs), ground‐motion correlation structures, and the estimation of design spectra (uniform hazard spectra, classical conditional mean spectrum (CMS) for a unique tectonic setting). In addition to these standard capabilities, the platform supports advanced features, not commonly found in existing seismic hazard codes, such as (a) computation of source parameters from earthquake catalogs, (b) vector‐probabilistic seismic hazard assessment, (c) hazard evaluation based on conditional GMMs and user‐defined GMMs, (d) uncertainty treatment in the median ground motions through continuous GMM distributions, (e) regional shaking fields, and (f) estimation of CMS considering multiple GMMs and multiple tectonic settings. The results from the platform have been validated against accepted and well‐documented benchmark solutions.

The present study proposes a tool for assessing universal accessibility in the interior of apartments, presenting a novel quantitative model for assessing the accessibility of buildings for buyers or tenants. For this, a multicriteria analysis for aggregating the assessment indicators with different units and scales is employed using a unique grade of accessibility according to four main pillars: Autonomy, Mobility, Comfort, and Safety. The assessment method has been applied in 35 show apartments in the urban area of Santiago in Chile. This work shows the application and results of 4 departments. The evaluation results are presented visually with a circular bar plot and a final grade in letter format from F to A. In general, it is observed that the four apartments proposed have a low degree of accessibility (letters F to D). And, the Autonomy pillar is clearly the lowest pillar in the selected apartments.

Accessibility to housing is crucial for people with disabilities as it provides them with equal opportunities and allows them to live independently. A systematic literature review has been conducted to understand the current research on accessibility in housing for people with disabilities in Latin America. The study analysed 56 papers and used co-word analysis to identify common themes and topics within the documents. The results of the analysis showed that Brazil (61%) is the country with the most research on the subject, physical disability, at 36%, is the impairment most analysed, and interventions or analysis for the older people (45%) in their homes is the most researched type of population. The co-word analysis revealed that topics such as policy, regulations, the use of technologies, ergonomics interventions, and architectural criteria or barriers to the daily life of disabled people were frequently discussed in the papers. Although this work shows a substantial and growing increase in research on housing for people with disabilities in Latin America, it also demonstrates the importance of increasing research on other types of impairment, such as visual and cognitive-intellectual disabilities, and including children, caregivers, or even young adults.

According to studies of accessibility in Chile show that the country is aging, by 2050 the population of the third age will increase to more than double where, in addition, the third of that group will develop some type of disability, with the physical type prevailing. Under this problem, Chile has modified his regulatory building body (OGUC) in 2016 establishing new design standards in order to have homes with basic characteristics of accessibility universal. But these modifications are not retroactive in housing policy. Because of this, the present study analyzes the incorporation of accessibility standards into social and private housing that are already built. Technically, it discusses basic solutions to comply with the regulatory approaches and then analyze the economic impact of the solutions, along with the modifications of non-structural elements for regulatory compliance without changing the useful surface of the housing. Showing to achieve accessibility in an existing private home the cost can increase by 0.08 UF/m2 and for social housing by 0.05 UF/m2. The study shows that with a good projection of the evolution of the people who will inhabit the houses, in conjunction with decisions from the design stage, they can have affordable housing at a low cost preventing the owner have to make large investments for adapt his house to any situation of disability that may be present throughout life. © 2020 Published under licence by IOP Publishing Ltd.

Considering that a significant part of the world's population lives with some disability and life expectancy is increasing, accessible transportation would allow people to improve their quality of life and access more socioeconomic opportunities. Based on a mixed descriptive design (qualitative, ethnographic, and quantitative), this article presents a tool for evaluating the level of accessibility to subway trains for people with visual, physical, cognitive, and hearing disabilities. Data from 30 Metro stations in Santiago de Chile were analyzed, studying movements into the station, permanence in the payment area, and movements toward platforms and connecting lines. Among the indicators evaluated, those related to getting to the platform have the lowest levels of accessibility, as they do not meet all the needs of the different types of disabilities analyzed.

AbstractThe labor market has transformed with the advent of the gig economy, characterized by short-term and flexible work arrangements facilitated by online platforms. As this trend becomes increasingly prevalent, it presents unique opportunities and challenges. In this manuscript, we comprehensively characterize the social networks of gig economy workers in each of the 15 cities studied. Our analysis reveals a scaling relationship between networks and the city population. In particular, we note the high level of modularity of the networks, and we argue that it results from the natural specialization of couriers along different areas of the cities. Furthermore, we show that degree and betweenness centrality is positively correlated with income but not with tenure. Our findings shed new light on the social organization of the gig economy workers and provide valuable insights for the management and design of gig economy platforms.

AbstractOver large regions exposed to natural disasters, cascading effects resulting from complex or concatenated natural processes may represent a large portion of total risk. Populated high‐mountain environments are a major concern, and methods for large‐scale quantitative risk analyses are urgently required to improve risk mitigation. This article presents a comprehensive quantitative rockfall risk assessment over a large archetypal valley of the Andean mountains, in Central Chile, which integrates a wide spectrum of elements at risk. Risk is expressed as an expected damage both in monetary terms and casualties, at different scales relevant for decision making. Notably, total rockfall risk is divided into its main drivers, which allows quantifying seismically induced rockfall risk. For this purpose, the local seismic hazard is quantified and the yield acceleration, that is, acceleration required to initiate rockfall, is determined at the regional scale. The probability of failure is thereafter derived in terms of annual frequency of rockfall initiation and integrated in the quantitative risk assessment (QRA) process. Our results show the significant role of seismic activity as the triggering mechanism of rockfalls, and highlight elements at risk that have a major contribution to the total risk. Eventually a sensitivity analysis is conducted to (i) assess the robustness of obtained risk estimates to the data and modeling choices and (ii) identify the most influential assumptions. Our approach evidences the feasibility of large‐scale QRAs in sensitive environments and opens perspectives for refining QRAs in similar territories significantly affected by cascading effects and multihazards.

In this study, we present predictive models for significant ground-motion duration from interplate and intermediate-depth intraslab earthquakes at Mexico City for the horizontal components, the vertical component, and the vertical-to-horizontal ratio case. The considered sites are located over several zones in Mexico City, from rock to soft-soil sites. For the ground-motion duration models, the significant durations for ranges between 5% and 75%, 5% and 95%, and 2.5% and 97.5% of Arias intensity are considered for the analyses. The equations were developed as functions of magnitude, distance of the earthquake, and site period using 16 and 23 event recordings from interplate and intermediate-depth intraslab earthquakes at the hill, transition, and lakebed zones of the city using mixed-effect regression analyses. For the intraslab events, in particular, the new database includes recordings from two significant normal-faulting events that occurred in 2017. The models lead to differences with respect to the previous models. Therefore, predictive models for both considered focal mechanisms are proposed. The model is valid for interplate events at distances from 280 to 500 km and magnitude Mw from 6 to 8.1, for intraslab events at distances of 100 km up to about 650 km, magnitude Mw from 5 to 8.2, and focal depths from 40 km to over 120 km.

Currently, the public health infrastructure in Chile, at its different scales, has made important advances in determining sustainability design criteria. However, it is possible to see that, during its construction, there are no standardized verification processes on sustainability aspects, and that the work of technical inspection focuses on the administrative compliance of construction contracts, rather than on checking technical aspects. This research proposes a list of critical items and activities to supervise hospital construction, to guarantee sustainable criteria in their operation. A survey was also made to professionals involved in the design, construction, and supervision of hospital construction, ranking the results with a multi-criteria methodology (AHP), which showed a preference in the thermal envelope (20%) and thermal and ventilation installations (17%). Finally, based on the weaknesses stated by the professionals, a control and monitoring process of these items and activities is proposed, redesigning the work of the Worksite’ Technical Inspector.

In block/panel caving mines the footprint geometry and the undercut level height are key planning elements that have a bearing on the project final value. Selection of these parameters obviously depends on the economic objective, but it is also strongly influenced by rock mass characteristics that define column extraction capacity from draw points. This paper presents a simple methodology that allows defining the footprint and the best height of draw (BHOD) based on column extraction velocities, which are defined with the aim of controlling mass rock dynamic response while caving is propagated.  The proposed methodology can be used by industry because of the ease of application. A study case is presented for a block model which is evaluated by both the proposed methodology and nominal profit estimation.