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A comparative study of soil metal concentrations in Chilean urban parks using four pollution indexes
(2022) Vega, Alejandra; Arce, Guillermo; Rivera, Javier I.; Acevedo, Sara E.; Reyes Paecke, Sonia; Bonilla, Carlos A.; Pasten Gonzalez, Pablo Arturo; CEDEUS (Chile)
Toxic metal enrichment in urban soils from natural and anthropogenic sources is a public health concern thatchallenges sustainable urban development. Active and legacy mining is likely a major contributor of localizedmetal pollution in resource-based economies, although other sources associated with industrial and trans-portation activities may also contribute in urban settings. In mining countries, such as Chile, with no soil qualityregulation, public policies that seek to protect human health should assess metal distribution and pollution in-dexes to guide interventions, especially in urban green spaces. To assess the role of active and legacy miningwaste sites within the urban and peri-urban areas, metal concentrations in the soils of urban parks weremeasured in this study, and four pollution indexes were calculated for four cities of Chile. Copiap ́o and Andacolloin northern Chile represented the cities with several active and legacy mining waste sites located within theurban and peri-urban areas, while conurbation La Serena-Coquimbo and Gran Santiago represented the cities inmining districts that lacked major mining waste sites within their urban perimeters. A total of 82 (Copiap ́o), 30(Andacollo), 26 (La Serena-Coquimbo), and 59 (Gran Santiago) composite surface soil samples were collectedfrom the urban parks. Considering Canadian guidelines for residential/parkland soils, the value for Cu (63 mg/kg) was found to be exceeded in 99%, 50%, 100%, and 97% of samples collected from Copiap ́o, La Serena-Coquimbo, Andacollo, and Gran Santiago, respectively. The guidelines for lead (140 mg/kg) and zinc (250mg/kg) were exceeded in less than 12% of samples collected from Copiap ́o and Gran Santiago. Arsenic was notmainly quantified (<10% quantification frequency, quantification limit = 36 mg/kg). The calculated modifiedpollution load, Nemerow, and soil quality indexes indicated that soils in the urban parks were more polluted incities with urban mine wastes, however, the pollution load index ranked higher metal pollution in Gran Santiago.This study presented the first comparative study of metals in urban parks of Chile, highlighting a large proportionof parks with soil copper concentrations above the international guidelines, while showing higher median values in cities containing urban mine waste disposal sites.
A lightweight fiber-based approach to reduce the risk of concrete detachment in shotcrete fortified tunnels
(2020) Ortiz, C.; Lillo Gallardo, Patricio Andrés; López Casanova, Mauricio Alejandro; CEDEUS (Chile)
A methodology for assessing the chemical and physical potential of industrially sourced rice husk ash on strength development and early-age hydration of cement paste
(2017) Zunino Sommariva, Franco; López Casanova, Mauricio Alejandro; CEDEUS (Chile)
Air Bubbles as an Admixture for Printable Concrete: A Review of the Rheological Effect of Entrained Air
(2022) Eugenin, C.; Navarrete, I.; Brevis Vergara, Wernher Ariel; Lopez, M.; CEDEUS (Chile)
Assessing and understanding the interaction between mechanical and thermal properties in concrete for developing a structural and insulating material
(2017) Remesar Lera, José Carlos; Vera Araya, Sergio Eduardo; López Casanova, Mauricio Alejandro; CEDEUS (Chile)
Awareness, actions, drivers and barriers of sustainable construction in chile
(2013) Serpell Bley, Alfredo; Kort, Jorge; Vera Araya, Sergio Eduardo; CEDEUS (Chile)
Collaborating in decision making of sustainable building design : An experimental study comparing CBA and WRC methods
(2016) Arroyo Riquelme, Paz; Fuenzalida, C.; Albert, A.; Hallowell, M.; CEDEUS (Chile)
Copper entrapment and immobilization during cement hydration in concrete mixtures containing copper tailings
(2021) Vargas, Felipe; Alsina, Marco A.; Gaillard, Jean-François; Pasten Gonzalez, Pablo Arturo; López, Mauricio; CEDEUS (Chile)
The use of copper tailings as supplementary cementitious material can reduce the environmental impacts ofconcrete production and the mining industry. A key concern limiting its application is the potential leaching oftoxic metals from the cementitious matrix, especially copper. To analyze and reduce the risk of leaching, themechanisms by which copper is entrapped in the cementitious matrix were investigated, by combining micro-scopic and spectroscopic approaches. Decreasing the water-to-binder ratio was statistically relevant to reducecopper leaching. Scanning Electron Microscope micrographs allowed to spatially localize enriched copperclusters within the cementitious hydration products. In the early stages of the cementitious hydration (i.e., 24 h),no spatial correlation between copper and hydration products was found; however, after seven days, copper wasspatially associated with calcium silicate hydrates. Cu K-edge X-ray absorption near edge structure spectroscopyprovided insights into the chemical speciation of copper in the cementitious matrix. It showed that copper sulfideand oxide phases persisted, whereas the copper sulfate phases were prone to dissolution and reprecipitation ascupric hydroxides induced by the relatively high pH from calcium hydroxides formed during hydration. Pro-moting the formation of hydration products can further reduce copper leaching from the alkaline cementitiousmatrix. A better understanding of metal entrapment mechanisms could lead to new strategies that reduce themobility of toxic elements when using copper tailings, increasing their use as a replacement of cement. With thisknowledge, it is expected to answer if it is possible to improve the copper entrapment into the cementitiousmatrix and if there is a risk of leaching once is entrapped.
Cuánto consumo supone el bienestar. Una geografía urbana basada en un índice de Sustentabilidad comunal en Chile
(Scielo, 2023) Gutiérrez Antinopai, Felipe Aníbal; Barton, Jonathan Richard; CEDEUS (Chile); Pontificia Universidad Católica de Chile. Instituto de Geografía
In the context of the UN 10-year Framework Programmes on Sustainable Production and Consumption (2012-2022), it is necessary to understand consumption patterns, mainly in urban areas. The municipal geography of consumption establishes a radical change in understanding urban sustainability merely as a challenge of poverty and low consumption. Through an Urban Sustainability Index, we identify patterns that reveal material processes and opportunities for wellbeing and levels of consumption. Focusing on the urban metabolism and indicators of impacts on intergenerational wellbeing, the index shows high levels of consumption in four municipalities and notable gaps in material and social conditions at the national and intra-regional scales. The article presents the municipal geography of wellbeing and consumption in Chile, in order to reveal the condition of urban sustainability to guide improvements in material and social conditions uncoupled from consumption. It also warns of the particular paradoxes of the development process.
Decoupling the physical and chemical effects of supplementary cementitious materials on strength and permeability : A multi-level approach
(2016) Zunino Sommariva, Franco; López Casanova, Mauricio Alejandro; CEDEUS (Chile)
Developing a very high-strength low-CO2 cementitious matrix based on a multi-binder approach for structural lightweight aggregate concrete
(2020) Mena, J.; González, Marcelo; Remesar Lera, José Carlos; López Casanova, Mauricio Alejandro; CEDEUS (Chile)
Development of a new supplementary cementitious material from the activation of copper tailings: Mechanical performance and analysis of factors
(2018) Vargas, Felipe; López Casanova, Mauricio Alejandro; CEDEUS (Chile)
Does energy efficiency matter to real estate-consumers? Survey evidence on willingness to pay from a cost-optimal analysis in the context of a developing country
(2018) Encinas Pino, Felipe; Marmolejo Duarte, Carlos; Sánchez De La Flor, Francisco; Aguirre, Carlos; CEDEUS (Chile)
Effect of supplementary cementitious materials on viscosity of cement-based pastes
(2022) Navarrete, I.; Kurama, Y.; Escalona, N.; Brevis Vergara, Wernher Ariel; Lopez, M.; CEDEUS (Chile)
Energy-efficient real estate or how it is perceived by potential homebuyers in four latin american countries
(2019) Encinas Pino, Felipe; Marmolejo Duarte, Carlos; Wagemann Farfán, Elizabeth; Aguirre Núñez, Carlos Andrés; CEDEUS (Chile)
Environmental impacts evaluation of treated copper tailings as supplementary cementitious materials
(2020) Vargas Muñoz, Felipe Andrés; López Casanova, Mauricio Alejandro; Rigamonti, L.; CEDEUS (Chile)
Environmental signature and health risk assessment of polybrominated diphenyl ethers (PBDEs) emitted from a landfill fire in Santiago de Chile
(2023) Pozo, Karla; Oyola, Germán; Jorquera, Hector; Gomez, Victoria; Galbán-Malagón, Cristobal; Mena-Carrasco, Marcelo; Audy, Ondřej; Příbylová, Petra; Guida, Yago; Estellano, Victor Hugo; Lammel, Gerhard; Klánová, Jana; CEDEUS (Chile)
Polybrominated diphenyl ethers (PBDEs) have been used as flame retardants in building materials, electronics, furnishings, vehicles, airplanes, plastics, polyurethane foams, and textiles for many years. Currently, the primary commercial mixtures, penta-, octa-, and deca-BDE, are globally restricted. Still, products containing PBDEs are expected to impact waste management and the environment for many years. In January 2016, an open fire in the Santa Marta landfill close to Santiago de Chile affected the city and surroundings. The fire caused several acute health effects and an increase in emergency hospitalizations. We measured PBDE levels in the areas affected by the fire in the air (gaseous and particulate) and soil, and PBDE emissions were estimated using a dispersion model. The results showed an increase in PBDE concentrations by a factor of 2–4 one day after the start of the fire. However, PBDE concentrations measured after the fire in PM10 and the gas phase were considered low compared to other regions. Interestingly, PBDEs’ patterns differed across the sites; however, BDE209 was the dominant congener for all environmental matrices. A preliminary risk assessment was conducted using the daily exposure dose (DED) by air inhalation estimation. The results showed low DED values for adults and children and suggested no direct health risk due to PBDE exposure. This study brings new data useful for future solid waste management initiatives in the country
Estimating the segregation of concrete based on mixture design and vibratory energy
(2016) Navarrete, I.; López Casanova, Mauricio Alejandro; CEDEUS (Chile)
Fare evasion in public transport: How does it affect the optimal design and pricing?
(Elsevier Ltd, 2023) Ramos Guerrero, Raúl Alfonso; Silva Montalva, Hugo Emilio; CEDEUS (Chile)
© 2023 Elsevier LtdFare evasion produces significant revenue losses in public transport systems. Recent research has found that low service quality and high prices are important determinants of fare evasion. However, the economic literature that studies the optimal public transport provision has overlooked the phenomenon. We develop a demand model of horizontal differentiation to investigate how fare evasion affects the design and pricing of public transport that maximizes utilitarian social welfare. We show analytically that fare evasion can create incentives to reduce public transport prices and improve service quality, putting upward pressure on its subsidization. We perform numerical simulations and sensitivity analysis to quantify the impact of these incentives on the public transport provision. These simulations confirm that the incentive to reduce fare evasion can lead to an optimal design and price that requires subsidies.
Flexural behavior of stratified reinforced concrete: construction, testing, analysis, and design
(2017) Navarrete, Ivan; Hube Ginestar, Matías Andrés; Kurama, Yayah; López Casanova, Mauricio Alejandro; CEDEUS (Chile)

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