Capítulos de libros

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A design procedure for buildings equipped with energy dissipation devices using nonclassical damping and iso-performance curves
(2019) Llera Martin, Juan Carlos de la; Munoz, Juan P.; Besa Vial, Juan José
A structured methodology for improving the owner-contractor relationship in construction projects
(Routledge. Taylor & Francis LTD, 1999) Serpell Bley, Alfredo
Given the complexity of the relationship between owners and contractors in construction projects, research work has been carried out to identify mechanisms to facilitate the understanding between these parts. Based on the Quality Function Deployment (QFD) approach, an exploratory study on the form of rationalising this relationship has been conducted and its preliminary results are presented in this paper. Within this research effort, a model that puts emphasis in the factors that, depending on the type of contract, can improve the performance of the project has been developed. This model helps to structure a set of information through a matrix scheme that allows the weighting of each relevant characteristic of the commercial relationship between the client and the contractor with the purpose of prioritising between them. The scheme uses a cross-impact approach and provides a sequential methodology that conditions the achievement of the owner's objectives to the actions of the contractor and to his own key contract management elements that influence the contractor's behaviour. It is proposed here that this methodology could constitute a useful decision tool for the owner when developing and executing a construction project.
Chapter 11 - The circulation of the Smart City imaginary in the Chilean context: A case study of a collaborative platform for governing security
(Elsevier, 2020) Tironi M.; Albornoz C.
The proliferation of technologies, devices, and digital platforms and their growing capacity to gather large amounts of data would seem to be delivering on the promise of a more automated, efficient, and Smart City. In this chapter, we examine the Smarty City circuit in Santiago de Chile and the ways in which various stakeholders bring meaning to this concept. We argue that the sociotechnical imaginary of the Smart City in the Chilean circuit has an ambiguous nature and it is interpreted through making and its positioning in various innovation events, urban laboratories, and government entities that articulate a collaborative network between the state, citizens and private enterprises. Furthermore, we analyze the case of the SoSafe platform, a Chilean smartphone application that seeks to reduce emergency response times through geolocalized reports made by citizens, exploring the scope and limits of the emergence of platform urbanism.
Collapse risk assessment of a Chilean dual wall-frame reinforced concrete office building.
(2019) Araya Letelier, Gerardo Andrés; López-García González, Diego; García, Andrés; Parra, Pablo Fernando; Candía, G.; Lagos, René
Economics of Water Resources
(Springer Cham, 2021) Donoso H., Guillermo; CDGA, Centro de Derecho y Gestión de Aguas, Pontificia Universidad Católica de Chile; Departamento de Economía Agraria, Facultad de Agronomía e Ingeniería Forestal, Pontificia Universidad Católica de Chile
Economic and social changes that have occurred in Chile in recent decades have affected water management in multiple ways. In particular, its adoption of an export-oriented growth strategy since the 1980s, based on developing natural-resource intensive activities in the primary sector has led to significant increases in water demand. Decoupling of economic growth from water demands is, thus, a priority so as to not limit future economic growth and social development. In this chapter an overview of the water sector in the national economy and growth is presented. Then the economic value of water resources is covered, analyzing its apparent productivity, as well as the water-energy-food nexus. Finally, some conclusions are presented.
Effectiveness of polypropylene fibers on impact and shrinkage cracking behavior of adobe mixes
(2019) Araya Letelier, Gerardo Andrés; Antico, Federico Carlos; Concha Riedel, José; Glade, Andres; Wiener, María J.
Earth has been used as construction material for thousands of years and still at present earthen shelters are widely inhabited due to their comfort and low environmental impacts. Despite their advantages, earthen materials are brittle and their performance can be enhanced with the addition of fibers. This study addresses the use of different dosages of micro-polypropylene fibers in adobe mixes. The results show that adobe mechanical damage performance is sensitive to the dosage of polypropylene fibers increasing impact strength and reducing drying shrinkage cracking.
Experimental Analysis of Helix Aspersa Shell as Cementitious Material
(Springer, 2024) Campos-Cortes, María José; Brescia-Norambuena, Leonardo; Retamoso, Claudia; Escalona Burgos, Néstor Guillermo
The high environmental impact of the cement industry demands the study of new cementitious materials. Often supplementary cementitious materials such as fly ash or silica fume are used; however, the depletion of raw materials encourages the assessment of new sources. Due to the high calcium content of snail shells, this research explored the use of crushed powder of Helix Aspersa to replace cement, evaluating its use at different percentages of replacement in weight (0, 5, and 10%), calcination temperature (0, 450, and 900 °C) and water-cementitious materials ratios (0.35, 0.40, and 0.45). The results included analysing setting time, compressive and flexural strength, water absorption, and shrinkage. Results indicated that snail shells (i) create an expansion during the first days (~15%), reaching similar values at 28 days, (ii) decrease the water absorption at calcination temperatures ≥450 °C, and (iii) slightly reduce the flexural strength (~16% in average) and compressive strength (~10% in average). As the main decrement of the responses is at a low w/cm ratio, it is expected that calcined snail shells offer the opportunity to save cement and pollution from the construction industry.
Experimental and Numerical Assessment of the In-Plane Behaviour of PG-RM Walls with Openings
(Springer, 2025) Vargas Carvajal, Laura Andrea; Sandoval Mandujano, Cristian; Bertolesi, Elisa; Tarque, Nicola; Calderón, Sebastián
This paper investigates how openings affect the in-plane response of partially grouted masonry (PG-RM) walls. The effect of the openings was assessed regarding shear capacity and failure mode through the cyclic test of four façadetype walls constructed with different opening sizes and with and without asymmetry. The results show that the shear capacity decreases with the opening’s height or width increment. It is also observed that geometric asymmetry generates differences between the lateral resistances of both in-plane loading directions. In addition, a two-dimensional finite element macro model using Abaqus was validated against the experimental results. The numerical strategy implemented satisfactorily represented the shear strength and failure mode of the tested walls. Considering the high complexity of representing the PG-RM behaviour, the proposed model is suitable for reproducing the PG-RM walls’ shear resistance and could be subsequently used further to investigate the effect of openings with different configurations.
Facing the impacts of COVID-19 in construction. The case of Chile
(Routledge, 2023) Serpell Bley, Alfredo Federico
The COVID-19 crisis has impacted all activities, both economic and social, in most countries. The construction industry, characterized by its intensive use of labor, has been particularly affected, receiving various negative impacts and having to seek different actions to face them. The aim of this work is to describe how the Chilean construction industry was affected by COVID-19 and how this pandemic has been faced both at the institutional level and at the level of each company to protect the health of workers and maintain the activity working productively. This description has been carried out by means of a literature review of local publications and reports. An analysis of these actions is included. Additionally, and according to available institutional studies, the effects of COVID-19 are reviewed in three important dimensions: the economic impacts of the pandemic, contractual impacts in the construction industry, and actions implemented to face the impacts of COVID-19. The information presented in this work can be used by the construction sectors of other countries as lessons learned as follows: a) to promote the industrialization in construction to reduce the exposition of people at the site; b) to increase the use of technology to supervise workers and help protect them; c) to disseminate good practices for handling the pandemic and apply new business models to maintain the operation; d) to accelerate the digital transformation of the industry to facilitate teleworking for many of its activities; e) to work collaboratively with suppliers; and f) to have contracts with greater clarity regarding the consequences resulting from a pandemic like COVID-19.
Influence of Joint Reinforcement on the Shear Behavior of Masonry Panels: Experimental and Numerical Assessment
(Springer Nature, 2025) Calderón, Sebastián; Fredes Siervo, José Ignacio; Sandoval Mandujano, Cristián
In seismic-prone regions, providing shear reinforcement is crucial for controlling the damage to masonry structural elements. In this context, shearresistant behavior has been the focus of several investigations due to its complexity and importance to withstand seismic demands. Different studies have intended to understand more in-depth how shear reinforcement improves the performance of reinforced masonry; despite these efforts, many questions remain open. For instance, it has been observed that shear reinforcement starts interacting with masonry only after cracks are developed. However, the pre-cracking behavior of reinforced and unreinforced masonry walls somewhat differ. Furthermore, it has been proven that the behavior of masonry built with different unit types (i.e., multi-perforated clay bricks, hollow concrete blocks, and solid clay bricks) may exhibit significant variations, implying that masonry built with all unit types must be evaluated. Motivated by this knowledge gap, this study assesses the behavior of masonry panels about 0.8 × 0.8 m made of multi-perforated clay brick, with and without shear reinforcement, and subjected to diagonal compression. Ladder-type steel reinforcement was placed at the mortar bed-joints. The experimental results are complemented with numerical simulations (detailed micro-models) to extend the achieved understanding. The study concluded that the horizontal reinforcement ratio did not significantly influence the behavior of the panels based on the findings that shear strength, shear strain, and shear modulus did not exhibit significant differences. Also, the reinforcement started collaborating with masonry only after the shear strength was achieved when specimens were too damaged to gain higher stresses.
Influence of jute fibers to improve flexural toughness, impact resistance and drying shrinkage cracking in adobe mixes
(2019) Concha Riedel, José; Araya Letelier, Gerardo Andrés; Antico, Federico Carlos; Reidel Hanenstein, Ursula; Glade, Andres
Flexural toughness, impact resistance and shrinkage cracking performance of earthen materials can be improved with the addition of fibers. There are limited studies addressing these properties in fiber-mixed adobe. This study investigates the use of jute fibers, a natural one derived from plants, in adobe mixes, including a sensitivity analysis on dosage and lengths of incorporated fibers. The results show that fiber-reinforced adobe’s flexural toughness and shrinkage are sensitive to the dosage, whereas impact resistance is sensitive to both fiber dosage as well as fiber length.
Innovation in the Chilean Construction Industry: Public Policy Instruments
(Routledge, 2001) Serpell Bley, Alfredo
The Chilean construction industry has expanded considerably during the last decade. However, this expansion has not been accompanied by a similar development in the way construction companies and projects are managed. Fundamental changes are required to improve the levels of productivity and particularly of quality. As part of a research project on Total Quality Management (TQM) in construction, a survey was undertaken with 24 Chilean construction companies to explore current Chilean construction management practices. An additional objective of this survey was to evaluate the adequacy of construction management to introduce quality improvement processes in construction projects. This paper reports the main results obtained from the survey. It has been structured in three sections: general management characteristics of the industry, construction companies’ management practices and site management practices. The work described contributes in that it identifies the main management deficiencies currently present in the Chilean construction industry and provides important information to design appropriate management improvement strategies and actions to correct them.La construction chilienne a augmenté considérablement au cours de la dernière décennie. Cependant, cette expansion n’a pas été accompagnée d’un développement pareil de la gestion des entreprises et projets de construction. Des changements fondamentaux sont nécessaires pour améliorer les niveaux de productivité et particulièrement de qualité. Faisant part d’une recherche sur Maîtrise Complète de la Qualité (TQM, Total Quality Management) en construction, une enquête fût menée auprès de 24 entreprises de construction chiliennes, pour faire le point sur les pratiques actuelles dans l’administration de construction. Un objectif additionnel de cette enquête fût l’évaluation de la capacité de l’administration de construction pour y introduire des démarches d’amélioration de la qualité aux projets. Cet article montre les principaux résultats tirés de l’enquête. Il compte trois sections: Caractéristiques générates de la gestion dans la construction, pratiques de gestion des entreprises, et pratiques de gestion en chantier. Le travail décrit contribue à identifier les principaux dysfonctionnements actuels de la construction au Chili, et donne une importante information pour la mise en place de stratégies d’amélioration de l’administration, et actions pour leur correction.
Introducción : la sociedad de consumo en contexto.
(RiL editores, 2015) Simone Polania, Rosa Liliana de
Motion estimation applied to reconstruct undersampled dynamic MRI
(2007) Prieto Vásquez, Claudia; Guarini Hermann, Marcelo Walter; Hajnal, Joseph V.; Irarrázaval Mena, Pablo
Magnetic Resonance Imaging (MRI) has become an important tool for dynamic clinical studies. Regrettably, the long acquisition time is still a challenge in dynamic MRI. Several undersampled reconstruction techniques have been developed to speed up the acquisition without significantly compromising image quality. Most of these methods are based on modeling the pixel intensity changes. Recently, we introduced a new approach based on the motion estimation of each object element (obel, a piece of tissue). Although the method works well, the outcome is a trade off between the maximum undersampling factor and the motion estimation accuracy. In this work we propose to improve its performance through the use of additional data from multiple coils acquisition. Preliminary results on cardiac MRI show that further undersampling and/or improved reconstruction accuracy is achieved using this technique. Furthermore, an approximation of the vector field of motion is obtained. This method is appropriate for sequences where the obels' intensity through time is nearly constant.
Polymer nanocomposites in additive manufacturing processes for typical applications in the industry
(Elsevier, 2020) Gonzalez-Henriquez C.M.; Sarabia Vallejos, Mauricio Alejandro; Rodriguez-Hernandez J.
Additive manufacturing (AM), commonly known as three-dimensional (3D) printing, is a widely used methodology that permits to fabricate fully customizable parts and objects with an astonishing level of geometrical complexity in a reduced time and with low costs. Polymers are, by far, the most widely used materials to fabricate 3D-printed parts due to its versatility and adaptability to many different environments or situations. The polymers used for AM could be used as carriers (or matrices) for nanocomposites of different nature. As a result, these composites could be used in a myriad of research and industrial fields such as aeronautics, automotive, architecture, energy supplies, food storage, optical, magnetical, microfluidic, and biomedical areas, among others.
Process mining in primary care: A literature review
(2018) Williams, Richard; Rojas Balcazar, Erick; Peek, Niels; Johnson, Owen A.
Process mining is the discipline of discovering processes from event logs, checking the conformance of real world events to idealized processes, and ultimately finding ways to improve those processes. It was originally applied to business processes and has recently been applied to healthcare. It can reveal insights into clinical care pathways and inform the redesign of healthcare services. We reviewed the literature on process mining, to investigate the extent to which process mining has been applied to primary care, and to identify specific challenges that may arise in this setting. We identified 143 relevant papers, of which only a small minority (n=7) focused on primary care settings. Reported challenges included data quality (consistency and completeness of routinely collected data); selection of appropriate algorithms and tools; presentation of results; and utilization of results in real-world applications.
Short-horizon return predictability and oil prices
(CRC Press, 2015) Casassus Vargas, Jaime Enrique; Higuera, Freddy
We nd that, at horizons of one to three quarters, the oil price shocks exhibit predictive performance which is both statistically and economically signicant. Obtaining signicant results in a sample period aer the oil crisis in the 1970s is not an easy task since most variables lose their forecasting power within this period (Welch and Goyal 2008). In terms of global performance, our variable is better than all other variables considered (consumption-wealth ratio, price-dividend ratio, output gap and risk-free rate) with an 2R of 6%. is meaningful in-sample result was also detected in out-of-sample tests. Our variable exhibited the best out-of-sample 2R, which was close to 1.2% at one quarter. For longer time horizons, however, no variable showed a signicant predictive performance.
The Online Set Aggregation Problem
(2018) Carrasco, Rodrigo A.; Pruhs, Kirk; Stein, Cliff; Verschae, José
The performance of the Chilean Construction Industry
(Routledge, 2021) Serpell Bley, Alfredo Federico; Ferrada Calvo, Ximena Veronica

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