La arquitectura vernácula en la selva tiene mucho valor histórico, ya que son las primeras construcciones de los primeros pobladores que habitaron en esta zona del Perú. En la región de Ucayali, las construcciones tradicionales están basadas en madera, bambú y hojas de palma, ya que son estos los materiales predominantes de la selva ucayalina. Así mismo, cabe recalcar que esta región era y es ocupada por la etnia Shipibo Conibo, quienes mantienen una cultura selvática con importancia a los dioses cósmicos, así también poseen mucha reverencia hacia la serpiente mítica el Yacumama. Pues, realizan ceremonias dirigido a estos personajes dentro de un ambiente con mucha importancia para estos, la cual es la maloca. Quien es una arquitectura de luz amplia con forma circular o rectangular y como concepto albergar a las principales autoridades de la etnia y/o todos los integrantes del grupo para realizar un evento; siendo este ambiente un espacio público. Por otro lado, el sistema constructivo empleado en épocas iniciales para la región está siendo desvalorizadas por los mismos ciudadanos en la actualidad. Ya que, lo califican como construcciones precarias, sin valor y de poca duración; por lo que se puede deducir que esta arquitectura antigua está en extinción en la ciudad. Por ese motivo se busca promover e incentivar; a través de arquitectura vernácula; a los ciudadanos, para que estos puedan usar materiales más accesibles y económico con un empleo de sistema constructivo reforzado, siendo la combinación de materiales industriales y naturales. / Vernacular architecture in the jungle has a lot of historical value, since they are the first constructions of the first settlers that inhabit this area of ​​Peru. In the Ucayali region, traditional buildings are based on wood, bamboo and palm leaves, since these are the predominant materials of the Ucayalina jungle. Likewise, it should be noted that this region was and is occupied by the Shipibo Conibo ethnic group, who have a jungle culture with importance to the cosmic gods, so we also have much reverence for the mythical serpent the Yacumama. Well, the ceremonies aimed at these characters in an environment that is very important for them, which is the maloca. Who is a wide light architecture with a circular or rectangular shape and as a concept to house the main authorities of the ethnic group and / or all the members of the group to carry out an event; this environment being a public space. On the other hand, the construction system used in early times for the region is currently being devalued by the same citizens. Since, what last as precarious constructions, without value and of short duration; so it can be deduced that this ancient architecture is in extinction in the city. For that reason it seeks to promote and encourage; through vernacular architecture; to citizens, so that they can use more accessible and economical materials with a use of reinforced construction system, being the combination of industrial and natural materials. / Trabajo de investigación

La presente investigación aborda la estabilización del adobe a través de la utilización de mucílago de penca de tuna con el fin de mejorar sus propiedades físicas como material de construcción. En la actualidad, el adobe es unos de los materiales más usados en la elaboración de viviendas en la Sierra del Perú por ser económico y de fácil adquisición; no obstante, este material al entrar en contacto con el agua pierde resistencia y durabilidad. Por tal motivo, esta tesis tiene como objetivo diseñar una unidad de albañilería de adobe estabilizado con mucílago de penca de tuna con el fin de prolongar la vida útil de las viviendas populares. Para validar esta investigación se realizaron diversos ensayos, para el suelo ensayos preliminares, de campo y laboratorio, para el mucilago ensayos de densidad y viscosidad; las unidades de adobes estabilizados y convencionales se analizaron través de ensayos mecánicos y físicos con la finalidad de comparar sus resultados. Los resultados obtenidos reflejaron que la unidad estabilizada presenta mejores resultados que el adobe convencional, se identificó que las dos mejores dosificaciones D: 20.5% y D: 18.0 % obtuvieron en compresión 23.3 kg/cm2 y 25.2 kg/cm2, en flexión 17.62 kg/cm2 y 17.61 kg/cm2, en absorción 10.99% y 11.43%, en inmersión se clasificó con daños leves y en la prueba de chorro de agua con 4.89 mm y 5.31 mm de profundidad de penetración respectivamente. / This investigation presents the stabilization of the adobe thanks to the use of prickly pear mucilage to improve its physical properties as a building material. Nowadays, adobe is one of the most used materials in the elaboration of houses in the mountains of Perú because it is economical and easy to acquire; however, when this material comes into contact with water, it loses strength and durability. For this reason, this thesis aims to design a stabilized of adobe masonry stabilized with mucilage of prickly in order to prolong the life of popular homes. In order to validate this investigation, several tests were carried out, for the soil preliminary, field trials and laboratory tests, and for the mucilage of prickly pear leaves with density and viscosity tests; for the stabilized and conventional adobe units, they were analyzed through mechanical and physical tests in order to compare their results. The results obtained in each trial reflected that the unit incorporated with mucilage of prickly has better results than conventional adobe, it was possible to identify that the two best dosages D: 20.5% and D: 18.0% obtained in the compression 23.3 kg / cm2 and 25.2 kg / cm2, in flexion 17.62 kg / cm2 and 17.61 kg / cm2, in absorption 10.99% and 11.43%, in immersion it was classified with slight damages and in the water jet test with 4.89 mm and 5.31 mm of depth of penetration respectively. / Tesis

En la actualidad las cantidades de residuos han incrementado con el pasar de los años, convirtiéndose en una amenaza grave para el medio ambiente. Esto ha generado que reciba mayor atención por las autoridades e investigadores a nivel global, proponiendo usos respetuosos con el medio ambiente de estos residuos, los cuales han ido desarrollando y mejorando en los últimos años. Este estudio profundiza en el posible uso del residuo de vidrio plano como una solución sostenible, al ser adicionados en el concreto. Para esto, se hicieron diseños de mezcla con diferentes cantidades de vidrio pulverizado y se realizaron comparaciones para identificar el efecto en las propiedades del concreto mediante ensayos de asentamiento, resistencia a la compresión y resistencia a la compresión en condiciones de ataque por sulfatos. Los resultados muestran que, para dichas pruebas, la adición de vidrio pulverizado favorece a las características de sus propiedades, presentando además un ahorro económico. / At present the amounts of waste have increased over the years, turning into a serious threat to the environment. This has generated greater attention by authorities and researchers around the world, proposing environmentally friendly uses of these residues, which have been developing and improving in recent years. This study delves into the possible use of pulverized flat glass waste as a sustainable solution, when added to concrete. For this, mixing designs were made with different amounts of glass powder and comparisons were made to identify the effect on the properties of the concrete by slump tests, compressive strength and compressive strength in sulfate attack conditions. The results show that for these tests, the addition of glass powder favors the characteristics of its properties, while presenting an economic saving. / Tesis

<p>Pasivni bežični LC senzori projektovani su u tehnologiji štampanih kola (PCB) i u tehnologiji nisko-temperaturno pečene keramike (LTCC). Predstavljena su tri tipa LC senzora izrađenih na PCB-u u jednoslojnoj i dvoslojnoj štampi. Takođe su prikazana i dva tipa LC senzora izrađenih u LTCC tehnologiji. Karakterizacija senzora je izvršena u laboratorijskim uslovima a za testiranje korišćeni su građevinska opeka i siporeks blok kao jedni od najčešće korišćenih materijala u građevinskoj industriji za zidane objekte.</p> / <p>Passive LC wireless sensors are designed in technology printed circuit boards (PCB) and the technology of Low Temperature Co-Fired Ceramics (LTCC). Presented are three types of LC sensors made on the PCB in the monolayer and bilayer press. It also presents two types of LC sensors manufactured in LTCC technology. Characterization of the sensor is carried out in the laboratory for testing were used building bricks and aerated concrete block as one of the most commonly used materials in the construction industry.</p>

<p>Silica fume is a widely used pozzolan in the concrete industry that has been shown to have numerous benefits for concrete including improved mechanical properties, refined pore structure, and densification of the interfacial transition zone between paste and aggregates. Traditionally, silica fume is used as a 5% to 10% replacement of cement; however, newer classes of higher strength concretes use silica fume contents of 30% or greater. At these high silica fume contents, many detrimental effects, such as poor workability and inconsistent strength development, become much more prominent. </p> <p> </p> <p>In order to understand the fundamental reasons why high silica fume contents can have these detrimental effects on concrete mixtures, eight commercially available silica fumes were characterized for their physical and chemical properties. These included traditional properties such as density, particle size, and surface area. A non-traditional property, absorption capacity, was also determined. These properties or raw material characteristics were then related to the hydration and rheological behavior of pastes and concrete mixtures. Other tests were performed including isothermal calorimetry, which showed that each silica fume reacted differently than other silica fumes when exposed to the same reactive environment. Traditional hydration models for ordinary portland cement were expanded to include the effects that silica fumes have on water consumption, volumes of hydration products, and final degree of hydration. </p> <p> </p> <p>As a result of this research, it was determined necessary to account for the volume and surface area of unhydrated cement and unreacted silica fume particles in water-starved mixture proportions. An adjustment factor was developed to more accurately apply the results from hydration modeling. By combining the results from hydration modeling with the surface area adjustments, an analytical model was developed to determine the thickness of paste (hydration products and capillary water) that surrounds all of the inert and unreacted particles in the system. This model, denoted as the “Paste Thickness Model,” was shown to be a strong predictor of compressive strength results. The results of this research suggest that increasing the paste thickness decreases the expected compressive strength of concretes at ages or states of hydration.</p> <p> </p> <p>The rheological behavior of cement pastes containing silica fume was studied using a rotational rheometer. The Herschel-Bulkley model was fit to the rheological data to characterize the rheological behavior. A multilinear model was developed to relate the specific surface area of the silica fume, water content, and silica fume content to the Herschel-Bulkley rate index. The Herschel-Bulkley rate index is practically related to the ease at which the paste mixes. This multilinear model was shown to have strong predictive capability when used on randomly generated paste compositions. </p> <p> </p> <p>Additionally, an analytical model was developed that defines a single parameter, idealized as the thickness of water surrounding each particle in the cementitious system. This model, denoted as the “Water Thickness Model,” incorporated the absorption capacity of silica fumes discovered during the characterization phase of this study and was shown to correlate strongly with the Herschel-Bulkley rate index. The Water Thickness Model demonstrates how small changes in water content can have a drastic effect on the rheology of low w/c or high silica fume content pastes due to the combined effects of surface area and absorption. The effect of additional water on higher w/c mixtures is significantly less.</p>

El presente trabajo de investigación, se realizó con la finalidad de diseñar y evaluar una mezcla de concreto adicionada con nanosílice con aplicación a canales hidráulicos de primer orden expuestos a sulfatos en la costa norte del Perú, siendo analizada la situación del Proyecto Especial Chavimochic: Etapa I. Esta investigación se desarrolla a nivel experimental y abarca ensayos con estándares nacionales e internacionales (NTP, ASTM y NTC) en los agregados, agua, concreto en estado fresco y concreto en estado endurecido. En busca de garantizar el aumento de ciertas propiedades de los elementos en contacto con agentes agresivos, como los sulfatos, se evalúan los beneficios de incorporar nanosílice en la mezcla de concreto con 0.2%, 0.225% y 0.25%. Siendo el segundo porcentaje de adición el cual evidencia mejor trabajabilidad para una relación agua/cemento de 0.45. Como resultados se obtuvo que el concreto con nanosílice (CNS) presenta menor contenido de aire que la mezcla de concreto simple (CS). Además, la resistencia a la compresión y a la tracción aumentan en 3.41% y 19.48%, respectivamente, a la edad de 28 días con la adición de nanosílice. Asimismo, para el ensayo a exposición a sulfatos, las probetas con nanosílice evidenciaron un deterioro promedio del 50% menor en todas sus aristas en comparación a las probetas de concreto simple. Adicionalmente, se analizó el coeficiente de permeabilidad (k) para ambas mezclas y se determinó que el CNS presenta una permeabilidad baja y el CS una permeabilidad media. / The present research was carried out with the purpose of designing and evaluating a mixture of concrete added with nanosilica for application to first order hydraulic channels exposed to sulphates in the north coast of Peru, being analyzed the situation of the Chavimochic Special Project: Stage I. This research is developed experimentally and includes trials with national and international standards (NTP, ASTM and NTC) in the aggregates, water, concrete in fresh state and concrete in hardened state. In order to analyze the increase of certain properties of the structural elements in contact with aggressive agents, such as sulphates, the benefits of incorporating nanosilica in the concrete mixture with 0.2%, 0.225% and 0.25% are evaluated. Being the second percentage of addition, which shows better workability for a water / cement ratio of 0.45. As a result, it was obtained that the nanosilica concrete (NSC) presents lower air content than the simple concrete mixture (SC). In addition, the resistance to compression and tensile increase in 3.41% and 19.48%, respectively, at the age of 28 days with the addition of nanosilica. Likewise, for the sulphate exposure test, the specimens with nanosilica showed an average deterioration of 50% lower in all its edges compared to the simple concrete specimens. Additionally, the permeability coefficient (k) for both mixtures was analyzed and it was determined that the NSC has a low permeability and the SC a medium permeability. / Tesis

Ante la problemática que presentan los suelos arcillosos de alta plasticidad, como la vulnerabilidad a variaciones de volumen, produciendo asentamientos diferenciales ocasionando daños en las estructuras, es por factores como este que se decidió buscar una alternativa de mejora para sus parámetros como el incremento de la resistencia, ángulo de fricción y cohesión de un suelo arcilloso de alta plasticidad (CH). En la ejecución de una obra civil, estos parámetros generalmente no se ajustan a los requerimientos del proyecto, por tal razón se debe buscar una solución para la estabilidad del suelo implicado en cualquier construcción. La constante búsqueda del mejoramiento de las condiciones ambientales ha llevado a la utilización de los residuos del plástico para reforzar el suelo y mejorar sus propiedades mecánicas y físicas. Es por ello que de acuerdo con nuestra propuesta se intenta incrementar data para el uso de este material alternativo como propuesta de mejoramiento del suelo, obteniéndose resultados interesantes y distintos a lo hallado en otras investigaciones que utilizaron similares materiales. Se optó por la trituración del tereftalato de polietileno (PET) obteniendo un PET reciclado de 3-5 mm de longitud como material de refuerzo para mejorar las propiedades mecánicas del suelo. De acuerdo con los ensayos de proctor estándar y corte directo, se determinó que el porcentaje óptimo de adición sea de 1% debido a que se observó un mejor comportamiento del material de estudio con respecto a las otras mezclas analizadas con 0.5%, 2.5% y 3.5%. / To the problems posed by clay soils of high plasticity, such as vulnerability to variations in volume, producing differential settlements causing damage to structures, it is due to factors such as this it was decided to seek an alternative enhancement to parameters such as increased resistance, friction angle and cohesion of a high plasticity clay soil (CH). In the execution of civil works, these parameters generally do not conform to the requirements of the project, for that reason should seek a solution for the stability of the soil involved in any construction. The constant search for improving environmental conditions has led to the use of waste plastic to reinforce the soil and improve its mechanical and physical properties. That is why according to our proposal we try to increase data for the use of this alternative material as a soil improvement proposal, obtaining interesting and different results to that found in other investigations that used similar materials. We chose crushing polyethylene terephthalate (PET) obtaining a recycled PET 3-5 mm length as a reinforcing material to stabilize and improve the mechanical properties of the soil. According to the standard proctor and direct shear tests, it was determined that the optimal percentage of addition is 1% because a better behavior of the study material was observed with respect to the other mixtures analyzed with 0.5%, 2.5% and 3.5%. / Tesis

Yes / Concrete requires a vast amount of aggregate and cement production. Although there are some efforts in the literature to reduce the amount of Portland cement in the concrete mixture to lessen the greenhouse gas release, a limited number of studies were conducted to investigate the possibility of using this geopolymer mixtures to serve as a structural component. Therefore, this study firstly aimed to produce geopolymer concrete from construction and demolition waste-based precursors, including masonry units (red clay brick, roof tile, hollow brick, etc.) and glass. In addition, recycled aggregates produced from the concrete waste portion of the CDW were used to obtain 100% recycled construction material on the scale of the binder and aggregate phase. Then, this study investigated the possible use of this proposed geopolymer concrete to produce structural components that perform similar to conventional concrete. Therefore, the structural properties of reinforced geopolymer concrete beams produced from the recycled construction demolition wastes were evaluated in this study by conducting laboratory experiments. To this end, bending tests were performed on reinforced conventional concrete beam specimens and reinforced geopolymer concrete beam specimens. The test observations clearly showed that construction demolition waste could be recycled to produce new constructional components, considering its advantage of promoted sustainability. / The authors gratefully acknowledge the European Union’s Horizon 2020 Research and Innovation Programme’s financial assistance under Grant Agreement No: 869336 and Acronym: ICEBERG and the financial assistance of the Scientific and Technical Research Council (TUBITAK) of Turkey and the British Council under Grant no:218M102. This work was also supported by Newton Prize 2020.

<p dir="ltr">Cold mix asphalt (CMA) is an eco-friendly paving material produced at ambient temperatures, offering energy savings by requiring less energy to decrease asphalt binder viscosity. This technology eliminates the need for heating during the mixing and compaction processes, further magnifying its economic benefits when used as a cold-in-place recycling technique. Unlike hot mix asphalts that gain strength through cooling, CMA achieves its final strength through a curing process involving the evaporation of volatiles and the hardening of the emulsified asphalt binder over time. However, its reliance on a curing process for strength development raises concerns about its short-term performance.</p><p dir="ltr">A typical CMA mixture consists of four main components: air voids, mineral aggregate, water, and asphalt droplets suspended in water. The presence of water can significantly influence the overall performance of the mixture under both traffic and environmental loads. Most existing studies on CMA have predominantly focused on the behavior of the mixtures after they have fully cured. However, in real-world scenarios, pavements are often subjected to various stresses during the curing process, which takes up to several months. As a result, premature distress can compromise the early performance of the pavement. Asphalt undergoes significant chemical and physical changes throughout this phase that can influence its final characteristics and in-situ performance. Overlooking this crucial stage can lead to a poor understanding of the material's capabilities and limitations. Despite the importance of this phase, the micromechanical and rheological behaviors of CMA during curing remain largely uncharted territories. Therefore, this dissertation aims to investigate the micromechanical performance of CMA during the curing phase.</p><p dir="ltr">This research study was performed in two study scales: Mastic and Mixture. The first scale focused on the rheological performance of emulsified-cold asphalt mastic (ECAM), considering varying curing levels, different filler-binder ratios, and filler surface treatments. Comprehensive rheological tests, including frequency sweep, temperature sweep, and strain sweep tests, were conducted on fully and partially cured mastic samples, i.e., 20%, 40%, 60%, and 80%, across a wide range of test temperatures. To analyze the physio-chemical adhesion properties between filler and emulsified asphalt, an analytical tool named the “asphalt-filler interaction” theory was formulated to determine the adhesion bond between filler and binder in the presence of moisture. Microscopic images were also captured to analyze the micro-structure and moisture interaction in the CMA’s matrix. Moreover, the presence of moisture in the CMA brings up another complexity during curing time: The water-to-ice phase transition. Normal Force (Nf) was used as a novel measurement parameter to determine water-ice phase transition effects on the rheological study of emulsified mastic. In the mixture scale, mechanical tests were performed on specimens fabricated with two gradations at fully and uncured CMA samples. The mixture experimental tests included the dynamic modulus test, Illinois flexibility index test, Hamburg wheel loaded test, and disc-shaped compact tension test.</p><p dir="ltr">This dissertation presents a thorough analysis and detailed findings that illuminate the complex relationships and behaviors of CMA, particularly at the mastic scale. A significant observation is the direct influence of the filler-to-binder ratio on the curing time; increasing this ratio prolongs the curing process while using a filler with less surface area accelerates it. Notably, 25% of the filler-to-binder ratio enhances the rheological properties of ECAM, particularly at lower loading frequencies. This study further pinpoints the 60% curing level as a crucial threshold in the CMA curing process. Below this, moisture's effect on rheological performance overshadows that of the primary asphalt material, leading to brittle characteristics in freezing conditions and viscous behavior at intermediate temperatures. In the curing stage, the trapped and blocked waters that emerge during the coalescence phase of the emulsified asphalt breaking contribute to the extended curing time of ECAM.</p><p dir="ltr">Additionally, freezing temperatures yield a water-to-ice phase change in uncured ECAM, resulting in a brittle behavior. Interestingly, a direct correlation emerges between curing percentage and freezing point; higher curing percentages relate to lower freezing points. Another significant discovery is the appearance of micropores in fully-cured ECAM, likely due to water evaporation and emulsifier presence, which potentially compromises its performance compared to ECAM fabricated with residual asphalt binder. Furthermore, adjusting the pH, especially by treating limestone filler with hydrochloric acid (HCl), showed noticeable improvements in CMA’s rheological behavior. At the mixture scale, the CMA mixture contained a higher filler-binder ratio in the mixture scale, presenting a better viscoelastic performance and higher cracking resistance at intermediate and freezing temperatures. Moreover, a minimum amount of water, 2.5% by total mass, added to the CMA mixture is essential to ensure adequate mixability, workability, and compactibility. Viscoelastic analysis showed that the curing process changes the transition point from elastic to viscous behavior of CMA mixtures. This shift towards lower frequencies results in a CMA mixture with poor resistance to higher temperature performance.</p>

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