WorldCat Identities

Pialarissi Cavalaro, Sergio Henrique

Overview
Works: 67 works in 69 publications in 3 languages and 69 library holdings
Roles: Author
Publication Timeline
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Most widely held works by Sergio Henrique Pialarissi Cavalaro
Proyecto de abastecimiento a Magallon by David Pi Bartomeus( )

2 editions published in 2012 in Spanish and held by 2 WorldCat member libraries worldwide

Estudio de la influencia del uso de la nanosílice en las propiedades del hormigón by Elena Montes Aceituno( )

2 editions published in 2012 in Spanish and held by 2 WorldCat member libraries worldwide

En la presente tesina se presenta el análisis realizado en hormigones de alta resistencia utilizando en su dosificación la adición de la nanosílice, un producto de reciente incorporación en el ámbito de la fabricación de hormigones. Se trata de una modificación del formato de presentación y de las dimensiones de las partículas de la microsílice, cuyo efecto puzólanico mejora las resistencias produciendo una densificación de la matriz
Evaluación de diferentes adiciones frente a su capacidad para fijar ión cloruro en morteros by Nelson Alberto Echeverría Melo( )

1 edition published in 2014 in Spanish and held by 1 WorldCat member library worldwide

New insights on the fundamentals and modeling of the external sulfate attack in concrete structures by Tai Ikumi Montserrat( )

1 edition published in 2018 in English and held by 1 WorldCat member library worldwide

The external sulfate attack (ESA) is a complex degradation process typically compromising the durability of underground foundations, nuclear or industrial waste containments and tunnel linings exposed to sulfate solutions. The structures affected usually remain covered its entire service life, which compromises the detection of this phenomenon before severe material degradation has occurred. Once diagnosed, the large size and criticality of the typical structures affected greatly limit the efficiency of the remedial actions. Consequently, monitoring of the evolution of the structural behavior is often the only applicable measure. This scenario places the development of reliable tools to assist the design of sulfate-resisting concrete structures and assess the risk of ESA in existing properties as key challenges for structural durability. The present thesis aims to advance knowledge in this field by presenting important contributions in three different research lines: numerical modeling of the ESA, role of porosity during the attack and the relevance of reproducing field-like conditions on ESA assessments. Advances on the ESA numerical modelization led to the development of a chemo-transport-mechanical model and a simplified assessment methodology. The former simulates the effects of ionic transport, chemical reactions, degradation mechanisms and the mechanical response of the structure. The validations performed indicate that the model captures the importance of the location of the ettringite formed within the pore network and provides a fair quantification of the overall expansions. The simplified assessment methodology evaluates the risk of failure during the ESA based on the aggressiveness of the media, the reactivity and mechanical properties of the material and the geometric characteristics and service life of the element under attack, without resorting to complex iterative algorithms. Unlike current design guidelines, the application of this simplified procedure allows the definition of flexible and optimized precautionary measures for each application. The second research line involved an extensive experimental program that led to the formulation of a conceptual model to explain the role of porosity during the ESA. The results obtained indicate that high durability against the attack might be achieved by limiting the penetration of sulfates or increasing the capacity of the matrix to accommodate expansive products. Both approaches correspond to opposing pore characteristics of the matrix: the former is usually associated with low porosities while the latter requires matrices with high porosities. These results question the common perception that high porosities are always negative for ESA durability and open up the possibility to design sulfate-resisting materials by increasing the capacity of the matrix to accommodate expansive phases. The third research line evaluates the influence of early sulfate exposure and the effects of confinement on the ESA by two experimental programs. The first study suggests that the delayed exposition to sulfates commonly adopted in accelerated laboratory tests might lead to imprecise damage estimations for structures cast in situ. In these cases, it is recommended to expose the samples to sulfates shortly after casting. The second study suggests that assessing sulfate resistance on specimens in free-expanding conditions might not be representative of the behavior of real structures where the attack is developed in combination with confining conditions. Results indicate that compressive stresses generated by confinement interact with the normal development of the attack by limiting or delaying the appearance of micro-cracks and reducing the amount of ettringite crystals exerting expansive pressures
Caracterización a Cortante de Hormigón Proyectado by Ricardo Antonio Mateo Santana( )

1 edition published in 2013 in Spanish and held by 1 WorldCat member library worldwide

El hormigón proyectado es un material singular ya que emplea aire como medio de colocación, posee una dosificación que contiene mayor proporción de áridos finos y limitación de tamaño máximo de áridos. Estas singularidades le confieren una menor densidad y menor resistencia que el hormigón moldeado con igual contenido de cemento. . Pese a estas inconvenientes, el hormigón proyectado combina dos etapas de la construcción en hormigón (colocación y compactación) en una misma acción lo que le hace un sistema de puesta en obra interesante desde el punto de vista de la ejecución. La combinación de etapas incrementa la velocidad de la obra y reduce costes de encofrados, de allí el gran atractivo económico que presenta. Por esta razón, desde mediados del siglo pasado, el desarrollo de nuevas máquinas, técnicas, adiciones y aditivos no ha parado. Ello hace que el hormigón proyectado mejore sus características y le proporciona mayor campo de aplicación. Si bien es cierto que la principal aplicación del proyectado es en túneles y reparaciones, aplicado a grandes superficies y pequeños espesores. A medida que avanza el desarrollo de la proyección, se ve como incursiona en otros tipos de construcciones estructurales. Para que siga ampliándose el uso del hormigón proyectado en estructuras de hormigón armado, es necesario conocer a fondo sus características y su comportamiento. Numerosos estudios se han realizado sobre temas de proyectado, abarcando áreas como: ejecución, durabilidad, resistencias a solicitaciones,mejoras de los materiales, entre otros. Pese a esto, aún se tienen incertidumbres frente a su comportamiento a solicitaciones estructurales, como es el caso de las solicitaciones a cortantes, tan importantes en las etapas de diseño. En busca de tener un mayor conocimiento de la respuesta a cortante del hormigón proyectado se plantea esta tesina. Para ello, se aborda el tema de hormigones proyectados en condiciones de laboratorio partiendo de pruebas a cortante y caracterización del material base en probetas moldeadas y comparando los resultados de sus pruebas con ensayos realizadas en el hormigón proyectado. Para la realización de la pruebas a cortante se emplea una variante del ensayo de Luong desarrollado en 1990 (Luong, 1990). Con este fue posible determinar la importancia que posee el confinamiento pasivo y el grado de humedad del hormigón en la resistencia a cortante, contribuyendo así al desarrollo del hormigón proyectado como material estructural
Caracterización y desarrollo de hormigones conductores by Eduard López Esplugas( )

1 edition published in 2015 in Spanish and held by 1 WorldCat member library worldwide

Estudio de durabilidad del hormigón con áridos siderúrgicos de horno de arco eléctrico by Yolanda Pérez Fernández( )

1 edition published in 2015 in Spanish and held by 1 WorldCat member library worldwide

Simulation of structural behavior of masonry using discrete element modeling by Alejandro Jiménez Ríos( )

1 edition published in 2016 in English and held by 1 WorldCat member library worldwide

The structural simulation of masonry elements has been traditionally conducted with Finite Element Models (FEM). Studies from the literature show that these models are capable of accurately reproduce the structural behavior at a micro and macro-scale levels. Despite the good results obtained, the application of FEM implies simplifications regarding the failure modes and the constitutive laws used to represent the behavior of bricks and mortar, as well as the interface between them. Alternative methods are available nowadays for the same purpose. An example is the Discrete Element Model (DEM) that is based on a particle-particle interaction. The simple definition of the interactions in the DEM is an advantage for the simulation of masonry elements. The objective of this master thesis is to evaluate the applicability of DEM to simulate the structural behavior of masonry at a micro and macro-scale level, reproducing the response in terms of deflections, ultimate load and failure modes. First, a review on the literature about DEM and about its application to the analysis of masonry structures was performed. Then, experimental programs conducted by other authors were selected and taken as a reference. Next, the tests found in these experimental programs were simulated with DEM. The numerical results were compared with the experimental data in order to highlight the accuracy, advantages and drawbacks of this approach. A parametric study was as well conducted to evaluate the sensibility of the results to changes in the input parameters of the model. Finally, further research proposals are presented in order to explore in a deeper and more extended way the topics presented on this dissertation It was found that the use of DEM to simulate the structural behavior of masonry at a micro and macroscale level, reproducing the response in terms of deflections, ultimate load and failure modes presents quite good results. Good agreement was shown in the description of failure modes and low percentage errors (below 10 %) were found on the computation of the parameters of interest such as strength of the material and maximum resistant load
Projecte constructiu de la Ronda Sud d'Igualada des de la ctra. C-37 (Santa Margarida de Montbui (Sant Maure)) a la ctra. A-2 (Jorba) by Alejandro Peña Colomer( )

1 edition published in 2014 in Catalan and held by 1 WorldCat member library worldwide

Accelerated cementitious matrices : hydration, microstructure and mechanical strength by Renan Pícolo Salvador( )

1 edition published in 2017 in English and held by 1 WorldCat member library worldwide

Sprayed concrete is widely used as structural support for the stabilization of tunnel walls and underground constructions. The performance of sprayed cementitious matrices containing accelerators is strongly related to their mechanical properties at early and late ages. In practice, this is the main parameter that governs their mix design and applicability. Mechanical strength development results from the combination of several factors associated with mix composition, application method and microstructure of the matrix. The compatibility between cement and accelerator is one of the most important parameters that control kinetics of hydration and the rate of mechanical strength gain. The spraying process also needs to be taken into account, since it leads to faster reaction rates and directly affects the porosity of the matrix. Although the sprayed concrete technology advanced considerably over the past years, questions continue to arise regarding its performance, efficient use and optimized mix design. One of the main subjects that requires further research is the characterization of the early age hydration behavior of accelerated cementitious matrices. The influence of accelerator reactions on the mechanical properties of the matrix at short and long term and the influence of spraying on kinetics of hydration also need to be evaluated. In this context, a study covering these demands is proposed in this doctoral thesis. The first subject contemplates the characterization of the kinetics and mechanisms of hydration and the microstructure development of accelerated cement pastes. The early age hydration behavior of different mix composition was analyzed and compared. Results obtained allowed the elucidation of the main chemical processes occurring during accelerator reaction and further cement hydration and their influence on the microstructure of the matrix. The second subject comprises the parametrization of the early age hydration behavior of cement pastes containing accelerators. The main chemical properties of cements and accelerators were evaluated, explaining their influence on accelerator reactivity and on cement hydration. By doing so, the mix design of accelerated cementitious matrices may be optimized and unpredictable hydration reactions and their consequences may be avoided. The third subject deals with the characterization of the setting and hardening processes of accelerated cementitious matrices by ultrasound measurements. This subject was proposed because the current standard methods to characterize early strength evolution are discontinuous and have a limited application range. By using the ultrasound technique, a more complete characterization of the evolution of mechanical properties of the matrix was assessed. The fourth subject aims at evaluating how spraying affects accelerator reactivity and further cement hydration. A small-scale spraying equipment was used to simulate real life applications of sprayed concrete. A significant influence of the mixing process on reaction rates and on microstructure of the matrix was observed. The last subject of this thesis focuses on the evaluation of how accelerated hydration reactions influence the mechanical strength development of the matrix. The main chemical processes influencing the mechanical properties at early and late ages were determined. Results provided the characterization of the mechanical performance of sprayed materials based on their chemical composition, in order to improve their mix design and quality control
Diseño de morteros para relleno de zanjas by Johanna Carleny Pérez Cuevas( )

1 edition published in 2014 in Spanish and held by 1 WorldCat member library worldwide

Aspectos tecnológicos de túneles construidos con tuneladora y dovelas prefabricadas de hormigón by Sergio Henrique Pialarissi Cavalaro( )

1 edition published in 2009 in Spanish and held by 1 WorldCat member library worldwide

Pasarela peatonal integrada en la estación de ferrocarriles de Tarragona by Iker Martín Loizaga( )

1 edition published in 2012 in Spanish and held by 1 WorldCat member library worldwide

El objetivo del presente proyecto es la definición de una pasarela peatonal que permita salvar el efecto barrera de las vías del ferrocarril cerca de la estación de ferrocarriles de Tarragona. Se estudiará también la posibilidad de integración de dicha pasarela en los servicios de la propia estación. Se analizarán las diferentes soluciones posibles a adoptar mediante un análisis multicriterio, donde se tendrán en cuenta criterios de diversa índole, para discernir cual es la alternativa más adecuada
Estudio de morteros para la sensorización de traviesas by Pablo Llopis Olcina( )

1 edition published in 2016 in Spanish and held by 1 WorldCat member library worldwide

Study on the behavior of cement matrices with alkaline and alkalifree set accelerators at low temperature by Xu Peng( )

1 edition published in 2017 in English and held by 1 WorldCat member library worldwide

Sprayed concrete is widely used as structural support for underground constructions. Although the sprayed concrete technology advanced significantly over the past years, questions continue to arise regarding its performance, efficient use and optimized design. One of the main subjects that requires further research is the behavior of sprayed cement matrices containing accelerators at low temperature, since the application of sprayed concrete may be hindered in regions with cold weather due to the difficulties to fulfill the requirements of fast setting and early age strength development under such conditions. Understanding the behavior of set accelerator at low temperature can provide useful information for predicting mechanical strength evolution and identifying the most efficiency mix proportions for real practice and constructions. In this context, a study of Vicat test and calorimetry test covering the main factors, which affect the behavior of cement matrices, including temperature, types of cement, types of set accelerator and content, was launched. About the Vicat test, four different temperature degrees: 20°C, 15°C, 10°C, 5°C were compared, for cement matrices, two types of cement: CEM I and CEM II were used, four types of set accelerator: ALNA73, AKF63, AKM55, AKF125 were added, with two dosages: 5% and 7%, excepting for mixes with ALNA73 which using a typical 3% content for alkaline based type. The composition of cement matrices for calorimetry test is the same with Vicat test, however experiments for mixes at 5°C was unable to reach due to some technical problem. The factor temperature; results from Vicat test present that low temperature delay the setting time of cement matrices in absolute terms, the alkaline accelerator, ALNA73 shows a general better performance over alkali-free set accelerators for cement matrices at low temperature. In relative terms alkali-free accelerator AKM55 and AKF125 are the most efficient accelerators, since they experience a general least efficiency index value when temperature reduced. If the parameters, heat flow and energy released in the hydration process are considered, low temperature affects the initial reaction of accelerator with cement, moreover delays the formation of hydration products, resulting the hydration reaction need longer time to finish, even now the hydration of cement and accelerator could occur independently. The factor type of set accelerator and content; the results from Vicat test and calorimetry test indicate that mixes with accelerator AKM55 show an abnormal behavior at low temperature. Increasing the content of accelerator used in cement matrices at low temperature could shorten setting time in absolute terms, whereas the increasing of content may not lead to a reduction in the loss of efficiency. The factor type of cement; generally, the types of cement does affects the behavior of cement matrices, whereas no clear tendency shows which type presents a better performance
Propuestas metodológicas para la caracterización de testigos de presas con problemas expansivos by Eduardo E Fernández de Castro Suárez( )

1 edition published in 2012 in Spanish and held by 1 WorldCat member library worldwide

[ANGLÈS] Some of the dams built in the region of Cataluña, have expansive processes that take place within its concrete, which is the case of the Graus dam. In this dam, observed movements are related in previous diagnoses to an internal sulfate reaction caused by the oxidation of iron sulfides present in the used aggregates. However, numerical simulations of the movements of the dam indicate that there may be a second expansive mechanism, delayed in time, which also contributes to these damages. With that in mind, the objectives of this study are to develop a methodology that serves as a general proposal to characterize concrete cores in dams, and also make a new diagnosis of the Graus dam to determine the reactions that effectively contributes to the expansion process. To do this, visual inspection was performed first, then critical areas in the dam where identified from the point of view of the damage. In these areas, extraction of concrete cores were realized and will be used in an extensive characterization process (visual inspection, selective dyeing, characterization of porosity, ultrasound tests and determination of permeability in O2) to confirm the real causes of the expansion. The results obtained in this study will serve as the foundations for more accurate diagnosis of the behavior of the Graus dam
Optimització de paràmetres per a la viabilitat d'una metodologia de tractament de fibra de vidre reciclada d'origen naval by María Elena Domínguez Sevilla( )

1 edition published in 2013 in Spanish and held by 1 WorldCat member library worldwide

La mayoría de las embarcaciones de recreo en desuso acaban en vertederos o hundidas en el mar. Para evitar el impacto medioambiental producido por esta acción, es necesario implantar normativas para el reciclaje y la gestión de los residuos resultantes. El material más abundante en estas embarcaciones es la fibra de vidrio que también acaba depositada en vertederos. Para reutilizarla, se está desarrollando una metodología de tratamiento para poder usarla como adición en morteros y hormigones. Para ello, las fibras han de presentar características álcali-resistentes. El presente trabajo se centra en optimizar parámetros de dicha metodología
Assessment of chloride corrosion in steel fibre reinforced cementitious composites by Mylene de Melo Vieira( )

1 edition published in 2018 in English and held by 1 WorldCat member library worldwide

High performance steel fibre reinforced cementitious composites (HPSFRCCs) show enhanced structural performance and durability. The improved properties favour its use in agressive conditions (such as marine environment) prone to corrosion. Despite the remarkable advances in the knowledge about corrosion of conventional reinforced concrete structures, questions still remain about its effects on the durability of HPSFRCC. The governing mechanisms of corrosion, the presence of cracks, the high steel fibre content, and the long-term chloride exposure still need to be properly evaluated. Given the increased application of HPSFRCC with structural responsibility and the high steel fibre content commonly used in the mixes, it is of great importance to understand the main mechanisms governing the chloride corrosion and its effects on the durability of the real-scale structures constructed with the material. To overcome these barriers and the uncertainty mentioned, this doctoral thesis adresses the following key issues: the effect of chlorides in uncracked HPSFRCCs under constant conditions; the influence of chloride corrosion in uncracked HPSFRCCs under wet-dry cycles with chlorides; the effect of corrosion in pre-cracked HPSFRCCs subjected to the same cycles and the proposal of a simplified model to consider the structural effects of corrosion. The first subject concerns the assessment of chloride corrosion on the aesthetic aspect and on the mechanical behaviour of HPSFRCCs by means of an accelerated test. For that, HPSFRCCs specimens with and without chlorides added to the mixes and with different fibre contents were tested. The preliminary experimental programme shows that, in general, the chlorides produce a level of surface corrosion with aesthetic consequences but have small influence on the mechanical performance. In the second subject, the influence of cycles was assessed in accelerated tests with uncracked HPSFRCCs prisms. The results reveal that, for uncracked HPSFRCCs elements, the corrosion affects the surface aspect but has no influence on the post-cracking response. The third subject focuses on the analysis of pre-cracked HPSFRCCs prisms under cyclic chloride exposure, considering different pre-crack widths and fibre contents. The study shows that the corrosion affects significantly the mechanical behaviour of the fibres for all specimens. The last subject covers a proposal of a simplified model to consider the effect of corrosion in the ULS design of HPSFRCC elements under cyclic chloride exposure. The model proposed was capable of reproducing the influence of the corrosion process over the cycles, being compatible with the current philosophy proposed in codes for the design of HPSFRCC structures
Diseño de una pasarela en Sant Andreu de la Barca by José Carrión Garruta( )

1 edition published in 2012 in Spanish and held by 1 WorldCat member library worldwide

Characterization and modelling of previous concrete by Ricardo Pieralisi( )

1 edition published in 2016 in English and held by 1 WorldCat member library worldwide

Pervious concrete is a special material with high permeability usually obtained by reducing the amount of fine aggregates in the composition of concrete. The properties of pervious concrete not only depend on its composition but also on the construction methods. The compaction process has a direct influence on the values of permeability and mechanical properties achieved. In fact, depending on the level of compaction applied, the same composition might give a highly pervious or even an almost impervious concrete. The interest of the scientific and technical community about pervious concrete has increased significantly since the 90's. Despite the technological advances on this field, the definition of the most adequate composition and compaction process to comply with the requirements of each application is normally based on trial and error or previous experiences. The lack of composition design methods in the literature may be attributed to the high complexity of the factors that intervene in the final performance of pervious concrete, which may hardly be generalized for all practical situations. In this context, the objective of this PhD thesis is to achieve a deeper understanding about pervious concrete and promote a new composition design philosophy based on advanced numerical simulations to minimize the need of experimental tests. This work covers the main aspects of production and performance of pervious concrete, from the fresh to the hardened state. The first subject refers to the compaction process in the fresh state. An Evolutionary Lattice Model is developed for simplified 2D simulations. As a more realistic alternative, new constitutive laws are developed and implemented in Discrete Element Models for 3D simulations. To validate these models, experimental programs that emulate a controlled compaction were performed. The results confirm the representativeness of the models developed. The second subject focuses on the permeability of concrete in the hardened state. The meso-structure derived from 3D simulations of the compaction process in the previous subject are evaluated in terms of their permeability. Computational Fluid Dynamics models are used to simulate the water flow through the material. An experimental program is conducted with a constant head permeameter and different types of pervious concrete. The results obtained are used to validate the numerical models, confirming that it is possible to reproduce the real permeability results based on combined numerical simulations of the compaction process and of the water flow within the material. The third subject is centred on the mechanical properties of pervious concrete in the hardened state. A new constitutive law is developed and implemented in DEM to simulate the interaction between the connected particles that form the material. The meso-structure obtained as a result of the compaction simulations are used to assess numerically the expected mechanical properties of the pervious concrete. An experimental program is conducted to evaluate the compressive and indirect tensile strength of pervious concrete with different compositions and subjected to several degrees of compaction. The numerical results estimated with this constitutive law together with the meso-structure show good agreement with the experimental results. The studies conducted in this work confirm that it is also possible to predict the performance expected in reality. Consequently, the numerical tools might be used to accelerate the process of defining the concrete composition and the production process for each application
 
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