O estudo da resistência à compressão e da deformabilidade de paredes de alvenaria de blocos de concreto é de fundamental importância para a caracterização desse material e o desenvolvimento de análises de estruturas compostas por esse tipo de painel. Este trabalho trata desse tema, objetivando prever com maior acuidade os principais parâmetros de deformação e de resistência de paredes de alvenaria de blocos de concreto, a saber: resistência à compressão e módulo de elasticidade longitudinal nas direções paralela e perpendicular à junta de assentamento. Foi desenvolvido um trabalho experimental para estimar a influência da resistência dos blocos, da resistência da argamassa e da direção de aplicação de forças no comportamento mecânico da alvenaria de blocos de concreto não-grauteada, quando submetida a esforços de compressão. Para tanto, realizaram-se ensaios de laboratório em blocos, argamassas, prismas de três blocos e paredinhas com dimensões de 80 cm x 80 cm. Por inferência estatística não foram obtidas correlações aceitáveis entre as variáveis estudadas. Porém, obtiveram-se tendências de comportamento dos corpos de prova estudados, confirmando a influência das características da argamassa e do bloco no comportamento estrutural da alvenaria quando submetida a esforços de compressão / The study of strength and the curved stress/strain relationship of blockwork masonry walls is basic for the material characterization and the development of structural analysis of blockwork walls. This work deals with that subject, aiming at the evaluation of the main elastic parameters and the strength of concrete blockwork walls: the compressive strength and modulus of elasticity for masonry in two orthogonal directions, parallel and perpendicular to bed joints. An experimental program was developed to evaluate the influence of the strength of blocks and mortar, and the load application direction on the mechanical behavior of ungrouted concrete block masonry under compression. A series of laboratory tests was carried out with blocks, mortar, prisms of three blocks and wallets (80 cm x 80 cm). It was impossible to obtain acceptable correlations of the defined variables, using statistical inference. However, tendencies of the specimens behavior were obtained, confirming the influence of mortar and block properties on the structural behavior of concrete blockwork walls under compression

O objetivo deste trabalho é avaliar a influência da variação do teor de umidade no valor do módulo de resiliência (MR) de um solo argiloso de subleito, tendo em vista que este parâmetro é muito susceptível à variações climáticas ambientais. Foram realizados ensaios triaxiais cíclicos para se estimar o módulo de resiliência de corpos de prova ensaiados em diversas condições de umidade. Verificou-se que o MR é influenciado pela tensão desvio, de forma que aquele aumenta com o acréscimo desta. Constatou-se que os corpos de prova moldados na Wot e submetidos a trajetórias de secagem e umedecimento alcançaram valores de MR superiores e inferiores, respectivamente, ao se comparar com o MR de corpos de prova ensaiados na Wot. Este fato foi também observado para os corpos de prova moldados com massa específica seca máxima, em teores de umidade abaixo e acima do teor ótimo. Determinou-se, ainda, a sucção no solo através do método do papel filtro e levantou-se a sua curva característica. Verificou-se que à medida que a umidade aumenta, a sucção diminui. Observou-se que o valor do MR aumenta com o aumento da sucção no solo. Este crescimento é tanto maior quanto maior seja a tensão desvio aplicada. Foi possível determinar a relação entre o MR, a tensão desvio e o módulo tangente inicial (Eo), proveniente dos ensaios de compressão simples. Relacionou-se, também, o Eo e a sucção no solo. / The aim of this work is to evaluate the influence of moisture content variation in resilient modulus value (MR) of a subgrade clayey soil, considering that this parameter is very susceptible to environmental climatic variations. Cyclic triaxial tests were performed to acess resilient modulus of specimens tested in several moisture conditions. lt has been verified that MR is influenced by deviator stress, so that the former increases with the latter increases. lt has been confirmed that specimens molded in Wot and submited to a drying and moistening route reached MR values higher and lower, respectively, to compare with MR of specimens tested in Wot. This fact was also observed for the specimens molded with dry density, in moisture contents below and above of optimum moisture content. lt has been also determined the soil suction using filter paper method and it has been built its characteristic curve. lt has been verified that when moisture increases, the suction decreases. lt has been observed that MR value increases with the soil suction increase. This increase is as bigger as bigger the applied deviator stress be. lt was possible to determine the relationship between MR, deviator stress and parameters from compressive strength tests. lt has been related parameters from compressive strength tests and soil suction.

Na construção de rodovias, as condições de umidade e densidade observadas na compactação são, geralmente, próximas daquelas correspondentes ao pico da curva de compactação obtida no ensaio Proctor. É sabido que variações ambientais no decorrer da vida do pavimento podem alterar, de maneira significativa, a umidade do subleito e dos seus componentes e assim, as suas propriedades resilientes. O objetivo principal desta pesquisa é avaliar a influência da variação da umidade pós-compactação no módulo de resiliência de solos de rodovias do interior paulista a partir de resultados de ensaios de laboratório. Foram coletados e caracterizados setenta e três solos, e, dentre estes, selecionados trinta para a etapa de estudo da variação da umidade pós-compactação, após a realização de ensaios MCT, difração de raios-x, microscopia eletrônica de varredura e azul de metileno para determinação da gênese. Os solos selecionados apresentam características distintas quanto à gênese, sendo metade laterítico e metade não-laterítico. Os corpos-de-prova foram compactados na umidade ótima e submetidos a processos de secagem e umedecimento e, posteriormente, realizados ensaios triaxiais cíclicos. Os resultados permitiram a modelagem do 'M IND.R' em função do estado de tensão para diferentes umidades e a avaliação da competência de alguns modelos matemáticos nesta representação. Estudou-se a influência da gênese e da granulometria sobre o valor do 'M IND.R' e avaliou-se a conseqüência da variação da umidade sobre este para solos lateríticos e não-lateríticos. Determinou-se uma expressão para estimar a variação do 'M IND.R' com a variação da umidade a partir do parâmetro k1, independentemente do estado de tensão. Pesquisou-se a existência de relações entre os parâmetros de regressão do modelo composto e os resultados dos ensaios de compressão simples e as propriedades físicas dos solos, de forma a permitir a estimativa do módulo de resiliência a partir do resultado de ensaios mais simples. Investigou-se a possibilidade de se utilizar as relações entre a variação do módulo tangente inicial com a variação da umidade para estimar os efeitos sobre o 'M IND.R'. / On road construction, the field compaction conditions are usually close to those determined from Proctor tests. Environmental variations may lead to changes in the pavement moisture and also changing its resilient properties. The main objective of this research is to study the influence of post-compaction moisture content variation on the resilient modulus of soils from São Paulo state pavements, using laboratory tests. To accomplish this objective, seventy three soils samples were collected and characterized. Among them, thirty samples were selected, after four different tests were carried out to determine the soils genesis, to study the post-compaction moisture content variation. Half of these selected soils are lateritic ones, and the other half are non-lateritic soils. The specimens were compacted at optimum moisture content and submitted to drying and moistening processes prior cyclic triaxial test to be carried out. The results allowed the resilient modulus modeling as a function at the stress state and the performance evaluation of five different models. The genesis and grain size distribution influence on the resilient modulus values were studied. The effects of moisture content variations on lateritic and non-lateritic soils were investigated. An expression to estimate the resilient modulus variations with the moisture variations was determined, independently of the stress state. The existence of relations of the compound model regression parameters with the results of unconfined compressive strength and soil properties were studied. The possibility of using the initial tangent modulus variations with the moisture variations to estimate the effects on the resilient modulus were also investigated.

Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-07-03T14:07:50Z No. of bitstreams: 1 pedrohenriquegarcia.pdf: 7575599 bytes, checksum: 5f088290c1ce19e54a605c6adc84e54f (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-08-08T12:27:34Z (GMT) No. of bitstreams: 1 pedrohenriquegarcia.pdf: 7575599 bytes, checksum: 5f088290c1ce19e54a605c6adc84e54f (MD5) / Made available in DSpace on 2017-08-08T12:27:34Z (GMT). No. of bitstreams: 1 pedrohenriquegarcia.pdf: 7575599 bytes, checksum: 5f088290c1ce19e54a605c6adc84e54f (MD5) Previous issue date: 2017-03-17 / O concreto de agregado leve é conhecido pelo reduzido peso específico e alta capacidade de isolamento térmico e acústico. Um dos grandes desafios relacionados a esse tipo de concreto é a obtenção de algumas propriedades mecânicas dos agregados leves, tais como o módulo de elasticidade e a resistência à compressão, em função de suas dimensões reduzidas, o que gera dificuldades na realização de ensaios experimentais. É possível encontrar trabalhos na literatura que tentam determinar as propriedades mecânicas dos agregados leves por meio de métodos baseados em formulações matemáticas e deduções empíricas. Uma alternativa a tais métodos é o emprego de modelos de simulação e a resolução de um problema inverso para a previsão de tais propriedades. O objetivo do trabalho é a aplicação de um procedimento inverso para obtenção do módulo de elasticidade e da resistência à compressão de agregados leves presentes em concretos via simulação computacional de ensaios de compressão uniaxiais em corpos de prova. O corpo de prova de concreto é representado por um modelo computacional mecânico bidimensional e bifásico, constituído por argamassa e agregados leves de formato circular, e as simulações foram conduzidas no programa Abaqus R. Os resultados encontrados foram satisfatórios em comparação com outros métodos da literatura, chegando a casos com diferenças menores que 2% para um corpo de prova com 15% de agregados. A abordagem proposta emerge como uma possível solução para análises de propriedades mecânicas de agregados leves em concretos com um reduzido tempo e custo, sendo aplicada para diversos tipos de curvas granulométricas, tipos de argamassa e diferentes porcentagens de agregados no corpo de prova. Além da previsão das propriedades mecânicas dos agregados em concretos leves, a abordagem traz um melhor entendimento da relação dos diversos conjuntos de agregados leves com as argamassas. / The lightweight aggregate concrete is known for its low specific weight and high thermal and acoustic insulation capacity. One of the great challenges related to this type of concrete is to get some mechanical properties of lightweight aggregate, such as the modulus of elasticity and the compressive strength, due to its reduced size, which generates difficulties to carry out experimental tests. It is possible to find works in the literature that try to determine the mechanical properties of the lightweight aggregate through methods based on mathematical formulation and empirical deductions. An alternative to such methods is the use of simulation models and the resolution of an inverse problem for the prediction of lightweight aggregate properties. The objective of this study is the application of an inverse procedure to obtain the modulus of elasticity and the compressive strength of lightweight aggregates present in concrete by computational simulation of uniaxial compression tests in specimens. The concrete specimen is represented by a two-dimensional and biphasic mechanical computational model, constituted by mortar and circular lightweight aggregates, and the simulations were conducted in the Abaqus R program. The results were satisfactory compared to other methods in the literature, reaching cases with differences of less than 2 % for a test specimen with 15 % of aggregates. The proposed approach emerges as a possible solution for the analysis of mechanical properties of lightweight aggregates in concrete with reduced cost and time, being applied for several types of grain sizes, mortar types and different percentages of aggregates in the concrete specimen. In addition, the approach brings a better understanding about the connection between lightweight aggregates and mortars.

La conception écologique des structures et le développement durable jouent un rôle important dans l'industrie de la construction. Les matériaux écologiques de construction tels que le béton de terre, contenant une proportion de divers composants écologiques, sont de grande importace aujourd'hui. L'objectif de la production de ce béton est de réduire la consommation de ciment et donc la production de CO2, de fournir des solutions pour éviter l’épuisement des ressources naturelles comme les granulats et de réduire la consommation d'énergie dans le processus de production.Ces dernières années, de nombreux efforts ont été réalisés dans le domaine de la construction pour remplacer le béton traditionnel par des matériaux alternatifs tels que le béton contenant une forte proportion de divers composants écologiques appelés « vert » en maintenant des propriétés acceptables pour l'application souhaitée. Par exemple, les constructions réalisées à partir de la terre crue sont intéressantes considérant leurs meilleures propriétés thermiques et acoustiques par rapport à un béton ordinaire. Cependant, des recherches additionnelles sont nécessaires pour mieux comprendre leurs propriétés mécaniques et leur durabilité.Cette étude vise à optimiser la composition d’un nouveau béton écologique constitué de sols locaux. Plusieurs mélanges composés de différentes proportions de sols argileux, de sols sableux et de faible quantité de ciment, de chaux et de fibres de chanvre ont été testés. La minéralogie et la composition chimique du sol argileux ont été étudiées par analyse des résultats obtenus par diffraction des rayons X (XRD) et par Microscopie à balayage électronique (ESEM) associée à la spectrométrie dispersive énergétique des rayons X (EDS). Le compactage des mélanges de béton de terre a été réalisé par vibration, comme dans le cas d’un béton ordinaire, pour obtenir l'ouvrabilité requise sur les chantiers de construction. Des essais de compression ont été effectués sur des éprouvettes d’âges différents et conservées dans différentes conditions de cure. La technique non destructive des ultrasons a été utilisée pour suivre le durcissement du béton de terre en fonction des conditions de cure. Les propriétés de transfert de ce béton ont été aussi étudiées en réalisant des essais de perméabilité, de porosité à l’eau, de porosimétrie à mercure et des essais d'absorption d'eau. La carbonatation de ce béton a été également évaluée. La durabilité du béton de terre a été examinée en suivant les déformations différées et plus particulièrement le retrait endogène et de dessiccation ainsi que le fluage en flexion. / The ecological design of structures and the sustainable development is nowadays of high importance in the construction industry. Thus, alternative building materials such as soil concrete containing a proportion of various ecological components are of high importance nowadays. The aim of producing ecological concrete is to reduce the consumption of cement and thus the CO2 production, to provide alternatives to the impoverishment of resources and to reduce the energy consumption in the production process.In recent years, many changes have been observed in the construction methods with the aim to replace traditional concrete by alternative construction materials such as concrete containing a high proportion of various ecological component called "green" while maintaining acceptable properties for the desired application. For instance, constructions made of cost effective raw soils are of real interest since the thermal and acoustic properties are more important than that of ordinary concrete. However, more researchs are needed in order to have a better understanding of their mechanical properties and their durability.This study aims to optimize the composition of a new ecological concrete constituted of upgraded excavated soil. Several soil concrete mixtures, composed of different proportions of clayey soil, sandy soil and small quantities of cement, lime and hemp fibers have been tested. The mineralogy and chemical composition of clayey soil was studied by X-ray diffraction (XRD) analysis, and by Environmental Scanning Electron Microscopy (ESEM) coupled with the X-Ray Energy Dispersive Spectrometry (EDS). The casting of the concrete mixtures has been realized by vibration, as ordinary concrete, to obtain the required workability on construction sites.Compressive tests have been carried out on samples at different curing time and conditions. The ultrasonic non-destructive technique has been used for monitoring the hardening of soil concrete in function of the curing conditions. As soil concrete presents important volumetric change that can cause the infiltration of water and impact their durability, an experimental investigation on autogenous and drying shrinkage is reported. Water porosity and water absorption tests have been also carried out to evaluate the transfer property of the porous material. The carbonation of this concrete was also evaluated. The durability of the soil concrete was examined by following the deferred deformations and more particularly the endogenous shrinkage and desiccation as well as the flexural creep.

L'objectif de la thèse est d'étudier l'effet de la quantité de fillers vis-à-vis des propriétés rhéologiques, mécaniques et dimensionnelles de bétons tout calcaire. Ces bétons ont été confectionnés avec les mêmes gravillons et le même sable provenant de la même production, afin d'éviter tout artéfact. Le sable a servi à fabriquer cinq sables représentatifs des catégories définies dans la norme EN 12260 des granulats à bétons, par mélange avec sa fraction fine ou sa fraction grenue extraites préalablement par lavage. Les sables fabriqués contiennent environ 0, 6, 12, 18 et 24% de fillers. Les bétons ont été formulés avec le logiciel BetonlabPro2, dont les algorithmes prennent en compte la présence des fillers calcaires. Les bétons ont été réalisés tout d'abord sans superplastifiant, puis en présence d'un superplastifiant dosé à 2/3 de la saturation. Les résultats obtenus ont montré qu'une quantité de fillers de 100 à 130 kg/m3 pour les bétons courants et de 60 à 80 kg/m3 pour les bétons superplastifiés, permet d'obtenir des propriétés optimales, à consistance égale. Mais des quantités supérieures de fillers n'altèrent pas significativement les propriétés des bétons, même si leur compacité diminue. On explique ce comportement non seulement par l'effet liant attribué aux fillers calcaires, mais aussi par une amélioration de la liaison pâte granulats. Les mélanges contenant les plus forts taux de fillers ont encore été étudiés pour formuler des bétons autoplaçants BAP, qui nécessitent une grande quantité de fillers. Les sables de concassage apportent alors la majeure partie de ce constituant, ce qui leur ouvre une voie nouvelle d'utilisation / The objective of this work is to study the effect of the quantity of fillers on the rheological, mechanical and dimensional properties of calcareous concretes. These concretes were made with the same coarse aggregates and same sand coming from the same production, in order to avoid any artifact. Sand was used to manufacture five sands representative of the categories defined in the EN 12260 norm for aggregates for concretes, by mixture with its fine fraction or its grained fraction extracted beforehand by washing. The employed sands contain approximately 0, 6, 12, 18 and 24 % of fillers. The concretes were formulated with the BetonlabPro2 software, whose algorithms take into account the presence of the fillers limestones. Concretes were realized at first without superplastifiant, then in the presence of a superplastifiant measured in 2/3 of saturation. The obtained results showed that a quantity of fillers limestones from 100 to 130 kg/m3 for the concretes and from 60 to 80 kg / m3 for superplasticizred concretes allows obtaining optimal properties, in equal consistency. But, higher quantities of fillers do not deteriorate significantly the properties of the concretes, even if their packing density decreases. One explains this behavior not only by the binding effect allotted to the fillers limestones, but also by an improvement of the paste-aggregates bond. Mixtures containing the strongest rates of fillers were again studied to formulate self compacting concretes SCC, which require a big quantity of fillers. Crushed sands bring then the major part of this constituent, what opens to them a new way of use

No description available.

In the light of extreme events of natural disasters (earthquakes or hurricanes) and accidents (fire or explosion), repairing and strengthening of existing concrete structures has become more common during the last decade due to the increasing knowledge and confidence in the use of composite advanced repairing materials. The past experience from real fires shows that it is exceptional for a concrete building to collapse as a result of fire and most fire-damaged concrete structures can be repaired economically rather than completely replacing or demolishing them. In this connection an experimental study was conducted to investigate the effectiveness of fibre reinforced polymer jackets for axial compressive and seismic shear performance of post-heated columns. This study also investigates the effectiveness of ferrocement laminate for the repairing of post-heated reinforced concrete columns.A total of thirty-five reinforced concrete columns were constructed and then tested after categorising them into three main groups: un-heated, post-heated and post-heated repaired. The post-heated columns were initially damaged by heating (to a uniform temperature of 500°C). The concrete cubes were also heated to various temperatures to develop the relation between compressive strength and ultrasonic pulse velocity. The residual compressive strength of the concrete cubes and reinforced concrete columns were determined by ultrasonic testing. The post-heated columns were subsequently repaired with unidirectional glass or carbon fibre reinforced polymer and ferrocement jackets. The experimental programme was divided into two parts. The columns of experimental part-1 were tested under axial compressive loading. The columns of experimental part-2 with a shear span to depth ratio of 2.5 were tested under constant axial and reversed lateral cyclic loading. The results indicated that the trend of reduction in ultrasonic pulse velocity values and in residual compressive strength of concrete was similar with increasing temperature. The reduction in residual stiffness of both post-heated square and circular columns was greater than the reduction in ultimate load. The circular sections benefited more compared to the square cross-sections with fibre reinforced polymers for improving the performance of post-heated columns in terms of compressive strength and ductility tested under axial compression. GFRP and CFRP jackets performed in an excellent way for increasing the shear capacity, lateral strength, ductility, energy dissipation and slowed the rate of strength and stiffness degradation of fire damaged reinforced concrete square and circular columns tested under combined constant axial and reversed lateral cycle loading. However, the effect of a single layer of glass or carbon fibre reinforced polymer on the axial stiffness of post-heated square and circular columns was negligible. The use of a ferrocement jacket for the repairing of post-heated square and circular columns enhanced the axial stiffness and ultimate load carrying capacity of columns significantly.

Hipótese do trabalho: Avaliar a presença de um orifício de acesso ao parafuso do intermediário do implante em infra-estruturas cimentadas sobre o pilar de titânio. Objetivo: O presente estudo visou comparar resistência a compressão de infra-estruturas em zircônia estabilizada por ítrio e em dissilicato de lítio cimentadas sobre pilar em titânio, com e sem acesso ao parafuso. Método: Foram confeccionados quarenta corpos-de-prova compostos por análogos de implantes hexágono externo de plataforma 4,1mm, intermediários de titânio pré-fabricado para próteses cimentadas e infra-estruturas para coroas totais. Os corpos-de-prova foram divididos em quatro grupos experimentais, sendo vinte, em cerâmica de zircônia estabilizada por ítrio(G1 e G2) e vinte em cerâmica de dissilicato de lítio(G3 e G4), todas confeccionadas com a mesma anatomia, ambas para próteses cimentadas sobre implante. Das vinte infra-estruturas de cada tipo de cerâmica, dez foram infra-estruturas convencionais para coroas cimentadas, constituindo o grupo controle e dez apresentavam um orifício de acesso ao parafuso, transpassando a cerâmica, constituindo o grupo experimental. As cimentações foram efetuadas com agente de fixação RelyX U200, de acordo com as especificações do fabricante, e o grupo experimental (com acesso ao parafuso) teve o orifício de acesso ao canal restaurado com resina composta foto ativada Z350 Filtek Supreme XT. Os corpos-de-prova foram submetidos a teste de compressão com velocidade de 0,5mm/minuto em máquina de ensaio universal. Resultados: Não foram encontradas diferenças estatísticas significativas entre infra-estruturas de cerâmicas convencionais e as infra-estruturas confeccionadas com orifício de acesso oclusal(G2 1.675 N/cm., G3 1.931 N/cm e G4 1.447 N/cm), exceto as infra-estruturas convencionais de zircônia estabilizada por ítrio que se apresentou superior aos demais(G1 3.372 N/cm). Com base nos resultados todas as modalidades de infra-estruturas testadas são viáveis para o uso clínico. / Hypothesis of work: To evaluate the presence of an access hole to screw the intermediate cemented implant in infrastructure over the titanium abutment. Objective: This study aimed to compare the compressive strength of infrastructure in yttrium stabilized zirconia and lithium disilicate cemented to abutment in titanium, with and without access to the screw. Method: Forty bodies-specimens consisting of similar external hex implants platform 4.1mm, intermediate titanium prefabricated for cemented prostheses and infrastructures for crowns were fabricated. The bodies-specimens were divided into four experimental groups, twenty, ceramic yttrium stabilized zirconia (G1 and G2) and twenty in ceramic lithium disilicate (G3 and G4), all made with the same anatomy, both for cemented prostheses on implants. Infrastructure of twenty of each type of tile ten were conventional infrastructure for cemented crowns, constituting the control group and ten had an access hole to the screw, trespassing ceramics, constituting the experimental group. The cementation were performed with RelyX U200 fixing agent, according to the manufacturers specifications, and the experimental group (with access to the screw) had the access hole channel restored with composite resin Z350 photo activated Filtek Supreme XT. The bodies-specimens were subjected to compression test speed of 0.5 mm / min in a universal testing machine. Results: No statistically significant differences between conventional ceramic infrastructure and infrastructure made with port access were found occlusal (G2 1675 N / cm, G3 1931 N / cm and G4 1447 N / cm.) Except conventional infrastructure stabilized zirconia yttrium who introduced himself superior to the others (G1 3300 N / cm). Based on the results of all modalities tested infrastructure are feasible for clinical use.

Objetivo: Comparar in vitro la resistencia compresiva de 2 resinas tipo Bulk: Tetric® N-Ceram Bulk Fill y Filtek ™ Bulk Fill vs 2 resinas tipo Core: Allcem Core y Fusión Core DC Flo utilizadas en la reconstrucción del núcleo dental. Materiales y Métodos: La muestra estuvo conformada por 80 especímenes. La unidad de análisis fueron cilindros de resinas (4 mm x 4 mm). Se dividieron en 4 grupos (n=20); G1 Allcem Core, G2 Fusion Core DC Flo, G3 Filtek ™ Bulk Fill, G4 Tetric® N-Ceram Bulk Fill. La resistencia compresiva fue evaluada con la máquina Instron® (velocidad de desplazamiento fijo de 1.0mm/min). Los datos fueron analizados mediante la estadística descriptiva (media y desviación estándar). Se compararon las variables, resistencia compresiva y resinas (Bulk y Core), mediante la prueba de Wilcoxon, Kruskal Wallis y la prueba de Post Hoc (prueba Dunntest) (p< 0.05). Resultados: La media y desviación estándar obtenida para la resina Filtek ™ Bulk Fill fue de 236.98±47.89, Tetric® N-Ceram Bulk Fill fue de 224.94±45.06, Allcem Core fue de 318.73±26.57 y para fue de Fusion DC Flo fue de 208.41±42.03. Al comparar las resinas tipo Bulk, no se encontró diferencias significativas (p=0.387). Sin embargo, sí se halló diferencias entre las resinas tipo Core (p<0.001). Al comparar los 4 grupos de resinas se encontró diferencias significativas (p=0.001), a favor de Allcem Core. Conclusión: La resina Allcem Core presentó mayor resistencia a la compresión en comparación a Filtek ™ Bulk Fill, Tetric® N-Ceram Bulk Fill y Fusión Core DC Flo. / Objective: To compare in vitro the compressive strength of two Bulk resins: Tetric® N-Ceram Bulk Fill and Filtek ™ Bulk Fill vs two Core resins: Allcem Core and Fusion Core DC Flo used in dental core reconstruction. Materials and Methods: The sample was made up of 80 specimens. The units of analysis were resin cylinders (4 mm x 4 mm). They were divided into 4 ºgroups (n = 20); G1 Allcem Core, G2 Fusion Core DC Flo, G3 Filtek ™ Bulk Fill, G4 Tetric® N-Ceram Bulk Fill. Their compressive strength was evaluated with the Instron® universal machine (fixed displacement speed of 1.0mm / min). The data was analyzed using descriptive statistics (mean and standard deviation). Compressive strength and resins (Bulk and Core) were compared using the Wilcoxon test, Kruskal Wallis and the Post Hoc test (Dunntest) (p <0.05). Results: The mean and standard deviation obtained for Filtek ™ Bulk Fill resin was 236.98 ± 47.89, Tetric® N-Ceram Bulk Fill was 224.94 ± 45.06, Allcem Core was 318.73 ± 26.57 and for Fusion DC Flo it was 208.41 ± 42.03. No significant differences were found between Bulk Fill resins (p = 0.387). However, significant differences were found between Core resins (p <0.001). Finally, significant differences were found among the four groups of resins (p = 0.001) highlight Allcem core resin. Conclusion: Allcem Core resin showed higher compressive strength compared to Filtek ™ Bulk Fill, Tetric® N-Ceram Bulk Fill and Fusion Core DC Flo. / Tesis