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The utilization of the vegetal fabric-reinforced cementitious matrix (FRCM) represents an innovative approach to composite materials, offering distinct sustainable advantages when compared to traditional steel-reinforced concrete and conventional FRCM composites employing synthetic fibers. This article introduces a design for sandwich solutions based on a core of extruded polystyrene and composite skins combining mortar as a matrix and diverse vegetal fabrics as fabrics such as hemp and sisal. The structural behavior of the resulting sandwich panel is predominantly driven by the interaction between materials (mortar and polyurethane) and the influence of shear connectors penetrating the insulation layer. This study encompasses an experimental campaign involving double-shear tests, accompanied by heuristic bond-slip models for the potential design of sandwich solutions. The analysis extends to the examination of various connector types, including hemp, sisal, and steel, and their impact on the shear performance of the sandwich specimens. The results obtained emphasize the competitiveness of vegetal fabrics in achieving an effective composite strength comparable to other synthetic fabrics like glass fiber. Nevertheless, this study reveals that the stiffness of steel connectors outperforms vegetal connectors, contributing to an enhanced improvement in both stiffness and shear strength of the sandwich solutions., Peer Reviewed, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant, Objectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.3 - Per a 2030, duplicar la taxa mundial de millora de l’eficiència energètica, Objectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles::11.1 - Per a 2030, assegurar l’accés de totes les persones a habitatges i a serveis bàsics adequats, segurs i assequibles, i millorar els barris marginal, Postprint (published version)

Composite beams are frequently used in building, combining a steel beam with either a concrete-filled steel deck or solid concrete slab. To ensure proper composite action, shear connectors, typically in the form of headed shear studs, are utilized. Traditionally, the strength assessment of these headed shear studs is made using empirical design specifications that are based on push-out tests, which have been widely conducted and standardized over the years. However, the standardized push-out tests have short-comings, such as uneven slab bearing, slab buckling, questions regarding the distribution of load to each stud, etc. A study was conducted to evaluate and compare the existing push-out test setup with two alternative test setups. The study also aimed to examine the behavior of headed shear studs in composite beams having deck deeper the current allowable limit of 3 in., as specified by American Institute of Steel Construction (AISC) design specification. While the standard specification allows for steel decks with rib heights of up to 3 in., there are deck profiles deeper than 3 in. available in the market. Utilizing these deeper decks in composite beams offers several advantages, including faster and more cost-effective construction by reducing the number of beams required. This research therefore found that a major challenge in creating an alternative test setup involves eliminating moment at the interface between the concrete-filled steel deck and the steel beam. This moment leads to tension in the headed shear stud/stud group closest to the actuator, thus affecting the shear strength of the headed shear studs. Further, these headed shear studs have significant strength when used with 3.5 in. decks but further research is necessary.

Rivets are permanent, non-threaded, one-piece fasteners that join parts together by fitting through a pre-drilled hole and deformed the head by mechanically upsetting from one end. In this paper the results of experimental analysis based on lap-shear test on riveted connection are presented. For experimentation specimens were prepared and different thickness and configurations were considered. The results of experimental test allowed the influence of various parameters such as plate width and pitch. These results are compared with the Ansys result. The experimental test using Universal Testing Machine and shear stress results are calculated. These results were compared with model simulation in FEA software.

Rivets are permanent, non-threaded, one-piece fasteners that join parts together by fitting through a pre-drilled hole and deformed the head by mechanically upsetting from one end. In this paper the results of experimental analysis based on lap-shear test on riveted connection are presented. For experimentation specimens were prepared and different thickness and configurations were considered. The results of experimental test allowed the influence of various parameters such as plate width and pitch. These results are compared with the Ansys result. The experimental test using Universal Testing Machine and shear stress results are calculated. These results were compared with model simulation in FEA software.

Rivets are permanent, non-threaded, one-piece fasteners that join parts together by fitting through a pre-drilled hole and deformed the head by mechanically upsetting from one end. In this paper the results of experimental analysis based on lap-shear test on riveted connection are presented. For experimentation specimens were prepared and different thickness and configurations were considered. The results of experimental test allowed the influence of various parameters such as plate width and pitch. These results are compared with the Ansys result. The experimental test using Universal Testing Machine and shear stress results are calculated. These results were compared with model simulation in FEA software.

Rivets are permanent, non-threaded, one-piece fasteners that join parts together by fitting through a pre-drilled hole and deformed the head by mechanically upsetting from one end. In this paper the results of experimental analysis based on lap-shear test on riveted connection are presented. For experimentation specimens were prepared and different thickness and configurations were considered. The results of experimental test allowed the influence of various parameters such as plate width and pitch. These results are compared with the Ansys result. The experimental test using Universal Testing Machine and shear stress results are calculated. These results were compared with model simulation in FEA software.

Rivets are permanent, non-threaded, one-piece fasteners that join parts together by fitting through a pre-drilled hole and deformed the head by mechanically upsetting from one end. In this paper the results of experimental analysis based on lap-shear test on riveted connection are presented. For experimentation specimens were prepared and different thickness and configurations were considered. The results of experimental test allowed the influence of various parameters such as plate width and pitch. These results are compared with the Ansys result. The experimental test using Universal Testing Machine and shear stress results are calculated. These results were compared with model simulation in FEA software.

Rivets are permanent, non-threaded, one-piece fasteners that join parts together by fitting through a pre-drilled hole and deformed the head by mechanically upsetting from one end. In this paper the results of experimental analysis based on lap-shear test on riveted connection are presented. For experimentation specimens were prepared and different thickness and configurations were considered. The results of experimental test allowed the influence of various parameters such as plate width and pitch. These results are compared with the Ansys result. The experimental test using Universal Testing Machine and shear stress results are calculated. These results were compared with model simulation in FEA software.

This work aims at giving a systematic review of the numerical approaches and obtained results published in recent years. Focus is set on both the recent trends and achievements as well as challenges and open questions. Thesis critically reviews work done in previous thesis related to food packaging material and design, at Blekinge Institute of Technology with the collaboration of Tetra Pak liquid food packaging company. Here, 27 numbers of master’s thesis are critical review all the while using 4 PHD works for referencing. Focus of these thesis works relates to the mechanics and its sub-branch fracture mechanics. Due to this all the theory related to mechanics and fracture mechanics, which is compulsory to know for understanding is defined initially. Main material which are under consideration throughout the work are PP, LDPE, PET-LDPE, and aluminum foil. As three materials are used in the liquid food packaging which are PE, paper board and aluminum. Uses of this material and there required physical properties are measured. Testing methods which are used to check whether the material meets the required parameters are tensile testing, tear testing, peel testing and shear test. Also, some methods are used along with these tests to perform the test more precisely, to evaluate and compare result i.e., Nakajima test, Digital image correlation. DIC testing technique is used to compare the results obtained from simulation. It is also understood that DIC method provided the user with increased quality of obtained results. Most of the topics of discussions have been reviewed for corresponding thesis, displaying the used ideas, theory, applied experimentation and realized conclusions. Using these above it was able to derive a conclusion based on the developed research questions and hypothesis. Defined problems in previous work are studied also solution as a future work is suggested to overcome these problems. Mainly the slippage issue while holding PE in clamps. Furthermor

Rivets are permanent, non-threaded, one-piece fasteners that join parts together by fitting through a pre-drilled hole and deformed the head by mechanically upsetting from one end. In this paper the results of experimental analysis based on lap-shear test on riveted connection are presented. For experimentation specimens were prepared and different thickness and configurations were considered. The results of experimental test allowed the influence of various parameters such as plate width and pitch. These results are compared with the Ansys result. The experimental test using Universal Testing Machine and shear stress results are calculated. These results were compared with model simulation in FEA software.

This work aims at giving a systematic review of the numerical approaches and obtained results published in recent years. Focus is set on both the recent trends and achievements as well as challenges and open questions. Thesis critically reviews work done in previous thesis related to food packaging material and design, at Blekinge Institute of Technology with the collaboration of Tetra Pak liquid food packaging company. Here, 27 numbers of master’s thesis are critical review all the while using 4 PHD works for referencing. Focus of these thesis works relates to the mechanics and its sub-branch fracture mechanics. Due to this all the theory related to mechanics and fracture mechanics, which is compulsory to know for understanding is defined initially. Main material which are under consideration throughout the work are PP, LDPE, PET-LDPE, and aluminum foil. As three materials are used in the liquid food packaging which are PE, paper board and aluminum. Uses of this material and there required physical properties are measured. Testing methods which are used to check whether the material meets the required parameters are tensile testing, tear testing, peel testing and shear test. Also, some methods are used along with these tests to perform the test more precisely, to evaluate and compare result i.e., Nakajima test, Digital image correlation. DIC testing technique is used to compare the results obtained from simulation. It is also understood that DIC method provided the user with increased quality of obtained results. Most of the topics of discussions have been reviewed for corresponding thesis, displaying the used ideas, theory, applied experimentation and realized conclusions. Using these above it was able to derive a conclusion based on the developed research questions and hypothesis. Defined problems in previous work are studied also solution as a future work is suggested to overcome these problems. Mainly the slippage issue while holding PE in clamps. Furthermor

Creating sustainability and public infrastructure is a fairly recent subject the engineering community has been debating. Introducing new building materials or introducing new structural designs is a strategy for constructing buildings that have long-term reliability and low maintenance requirements. Fiber-reinforced polymers (FRP) are one of the innovative approaches in the field of civil engineering that offer promising results in this regard. In order to maximize the usage of FRP forms, researchers suggested the development of hybrid structural structures by mixing composite materials with standard materials, such as concrete, to enhance the stability, ductility and buckling resistance of single FRP members. Nevertheless, these composite solutions need more preliminary research to prove its feasibility due to the complexity and large range of hybrid components. However, as there is a current shortage of compulsory codes for the design of composite structures and consequently FRP-concrete members, accurate predictive models need to be created. Thus, the present work aims at testing the structural efficiency of hybrid slabs made of CFRP sheets under a concrete layer in bending and shear configurations by carrying an experimental and analytical analysis. Using Carbon Fiber Reinforced Polymer (CFRP) bonded with resin is usual to strengthen concrete slabs or other elements. This thesis introduces a novel technological definition of thin CFRP-concrete unidirectional hybrid slabs. In bending part, experimental quasi-static three-points bending tests and modal analysis tests were carry out to analyze the influence of the connection systems on the dynamic response. Moreover, the corresponding analytical methodology to calculate their response are presented. Four different connection strategies between CFRP sheet and concrete were tested. These included flexible mesh embedding and particle-based frictional enhancement. The maximum bending moment, the evolution of the neutr, La creació d'infraestructura pública i sostenible és un tema de plena actualitat que la comunitat de l¿enginyeria ha estat debatent des de fa anys. Els polímers reforçats amb fibra (FRP) són un dels materials innovadors en el camp de l'enginyeria civil que ofereixen resultats prometedors en aquest sentit. Per maximitzar l'ús de formes de FRP s'estan desenvolupant estructures híbrides barrejant materials compostos amb materials tradicional, com el formigó, per millorar l'estabilitat, ductilitat i resistència al vinclament de membres individuals de FRP. A més, com hi ha una escassetat actual de codis obligatoris per al disseny d'estructures compostes i, en conseqüència, elements de formigó FRP, cal crear models predictius necessaris perquè es puguin estandarditzar. Abordar els problemes esmentats anteriorment és essencial per augmentar la introducció de materials compostos avançats en tipus comuns d'obres i construccions públiques. Així, el present treball té com a objectiu provar l'eficiència estructural de lloses híbrides de làmines de CFRP amb una capa de formigó, en configuracions de flexió i tallant, mitjançant la realització d'un anàlisi experimental i analític. L'ús de polímers reforçats amb fibra de carboni (CFRP) unit amb resina és habitual per reforçar lloses i altres elements de formigó. Aquesta tesi introdueix una definició tecnològica innovadora de lloses híbrides unidireccionals de formigó-CFRP de làmina prima. A la part de flexió es van realitzar assajos experimentals de flexió quasiestàtics, de tres punts, i assajos d'anàlisi modal per analitzar la influència dels sistemes de connexió en la resposta dinàmica. Així mateix, es presenta la metodologia analítica corresponent per calcular la seva resposta. Es van provar quatre estratègies de connexió diferents entre la làmina de CFRP i el formigó. Aquestes van incloure l¿embegut de malla flexible en el formigó i la millora de la fricció basada en partícules. El moment flector màxim, l'evolució de l'eix neut, La creación de infraestructura pública y sostenible es un tema de plena actualidad que la comunidad de ingenieros ha estado debatiendo desde hace años. La introducción de nuevos materiales de construcción o la introducción de nuevos diseños estructurales es una estrategia eficiente para construir edificios que tengan fiabilidad a largo plazo y requisitos de bajo mantenimiento. Los polímeros reforzados con fibra (FRP) son uno de los materiales innovadores en el campo de la ingeniería civil que ofrecen resultados prometedores en este sentido. Para maximizar el uso de formas de FRP se están desarrollando estructuras híbridas mezclando materiales compuestos con materiales estándar, como el hormigón, para mejorar la estabilidad, ductilidad y resistencia al pandeo de miembros individuales de FRP. Sin embargo, estas soluciones compuestas necesitan más investigación preliminar para demostrar su viabilidad debido a la complejidad y la amplia gama de componentes híbridos. Además, como existe una escasez actual de códigos obligatorios para el diseño de estructuras compuestas y, en consecuencia, elementos de hormigón FRP, es necesario crear modelos predictivos precisos para que puedan estandarizarse. Abordar los problemas mencionados anteriormente es esencial para aumentar la introducción de materiales compuestos avanzados en tipos comunes de obras y construcciones públicas. Así, el presente trabajo tiene como objetivo probar la eficiencia estructural de losas híbridas de láminas de CFRP con una capa de hormigón, en configuraciones de flexión y cortante, mediante la realización de un análisis experimental y analítico. El uso de polímeros reforzados con fibra de carbono (CFRP) unido con resina es habitual para reforzar losas y otros elementos de hormigón. Esta tesis introduce una definición tecnológica novedosa de losas híbridas unidireccionales de hormigón-CFRP de lámina delgada. En la parte de flexión se realizaron ensayos experimentales de flexión cuasi estáticos, de tres pun, Postprint (published version)

This work aims at giving a systematic review of the numerical approaches and obtained results published in recent years. Focus is set on both the recent trends and achievements as well as challenges and open questions. Thesis critically reviews work done in previous thesis related to food packaging material and design, at Blekinge Institute of Technology with the collaboration of Tetra Pak liquid food packaging company. Here, 27 numbers of master’s thesis are critical review all the while using 4 PHD works for referencing. Focus of these thesis works relates to the mechanics and its sub-branch fracture mechanics. Due to this all the theory related to mechanics and fracture mechanics, which is compulsory to know for understanding is defined initially. Main material which are under consideration throughout the work are PP, LDPE, PET-LDPE, and aluminum foil. As three materials are used in the liquid food packaging which are PE, paper board and aluminum. Uses of this material and there required physical properties are measured. Testing methods which are used to check whether the material meets the required parameters are tensile testing, tear testing, peel testing and shear test. Also, some methods are used along with these tests to perform the test more precisely, to evaluate and compare result i.e., Nakajima test, Digital image correlation. DIC testing technique is used to compare the results obtained from simulation. It is also understood that DIC method provided the user with increased quality of obtained results. Most of the topics of discussions have been reviewed for corresponding thesis, displaying the used ideas, theory, applied experimentation and realized conclusions. Using these above it was able to derive a conclusion based on the developed research questions and hypothesis. Defined problems in previous work are studied also solution as a future work is suggested to overcome these problems. Mainly the slippage issue while holding PE in clamps. Furthermor

This work aims at giving a systematic review of the numerical approaches and obtained results published in recent years. Focus is set on both the recent trends and achievements as well as challenges and open questions. Thesis critically reviews work done in previous thesis related to food packaging material and design, at Blekinge Institute of Technology with the collaboration of Tetra Pak liquid food packaging company. Here, 27 numbers of master’s thesis are critical review all the while using 4 PHD works for referencing. Focus of these thesis works relates to the mechanics and its sub-branch fracture mechanics. Due to this all the theory related to mechanics and fracture mechanics, which is compulsory to know for understanding is defined initially. Main material which are under consideration throughout the work are PP, LDPE, PET-LDPE, and aluminum foil. As three materials are used in the liquid food packaging which are PE, paper board and aluminum. Uses of this material and there required physical properties are measured. Testing methods which are used to check whether the material meets the required parameters are tensile testing, tear testing, peel testing and shear test. Also, some methods are used along with these tests to perform the test more precisely, to evaluate and compare result i.e., Nakajima test, Digital image correlation. DIC testing technique is used to compare the results obtained from simulation. It is also understood that DIC method provided the user with increased quality of obtained results. Most of the topics of discussions have been reviewed for corresponding thesis, displaying the used ideas, theory, applied experimentation and realized conclusions. Using these above it was able to derive a conclusion based on the developed research questions and hypothesis. Defined problems in previous work are studied also solution as a future work is suggested to overcome these problems. Mainly the slippage issue while holding PE in clamps. Furthermor

This work aims at giving a systematic review of the numerical approaches and obtained results published in recent years. Focus is set on both the recent trends and achievements as well as challenges and open questions. Thesis critically reviews work done in previous thesis related to food packaging material and design, at Blekinge Institute of Technology with the collaboration of Tetra Pak liquid food packaging company. Here, 27 numbers of master’s thesis are critical review all the while using 4 PHD works for referencing. Focus of these thesis works relates to the mechanics and its sub-branch fracture mechanics. Due to this all the theory related to mechanics and fracture mechanics, which is compulsory to know for understanding is defined initially. Main material which are under consideration throughout the work are PP, LDPE, PET-LDPE, and aluminum foil. As three materials are used in the liquid food packaging which are PE, paper board and aluminum. Uses of this material and there required physical properties are measured. Testing methods which are used to check whether the material meets the required parameters are tensile testing, tear testing, peel testing and shear test. Also, some methods are used along with these tests to perform the test more precisely, to evaluate and compare result i.e., Nakajima test, Digital image correlation. DIC testing technique is used to compare the results obtained from simulation. It is also understood that DIC method provided the user with increased quality of obtained results. Most of the topics of discussions have been reviewed for corresponding thesis, displaying the used ideas, theory, applied experimentation and realized conclusions. Using these above it was able to derive a conclusion based on the developed research questions and hypothesis. Defined problems in previous work are studied also solution as a future work is suggested to overcome these problems. Mainly the slippage issue while holding PE in clamps. Furthermor

This work aims at giving a systematic review of the numerical approaches and obtained results published in recent years. Focus is set on both the recent trends and achievements as well as challenges and open questions. Thesis critically reviews work done in previous thesis related to food packaging material and design, at Blekinge Institute of Technology with the collaboration of Tetra Pak liquid food packaging company. Here, 27 numbers of master’s thesis are critical review all the while using 4 PHD works for referencing. Focus of these thesis works relates to the mechanics and its sub-branch fracture mechanics. Due to this all the theory related to mechanics and fracture mechanics, which is compulsory to know for understanding is defined initially. Main material which are under consideration throughout the work are PP, LDPE, PET-LDPE, and aluminum foil. As three materials are used in the liquid food packaging which are PE, paper board and aluminum. Uses of this material and there required physical properties are measured. Testing methods which are used to check whether the material meets the required parameters are tensile testing, tear testing, peel testing and shear test. Also, some methods are used along with these tests to perform the test more precisely, to evaluate and compare result i.e., Nakajima test, Digital image correlation. DIC testing technique is used to compare the results obtained from simulation. It is also understood that DIC method provided the user with increased quality of obtained results. Most of the topics of discussions have been reviewed for corresponding thesis, displaying the used ideas, theory, applied experimentation and realized conclusions. Using these above it was able to derive a conclusion based on the developed research questions and hypothesis. Defined problems in previous work are studied also solution as a future work is suggested to overcome these problems. Mainly the slippage issue while holding PE in clamps. Furthermor

Nanoparticles have advantageous small-size and surface effects that impart them with unique mechanical properties. To evaluate these properties, a constant-volume shear tester that can precisely measure stresses on the shear plane was used. Six samples, namely, hydrophilic and hydrophobic silica, alumina, and titania nanoparticles, were prepared for the shear tests. For each sample, a single shear test provided the void fraction, stress relaxation ratio, stress transmission ratio, powder yield locus, consolidation yield locus, critical state line, shear cohesion, and flow function. All the tests were conducted under ambient conditions using powder beds, in which the void fractions were in the range of 0.89–0.96. A series of analyses demonstrated that the hydrophilic nanoparticles have lower flowability than the hydrophobic nanoparticles, indicating that moisture on the surface increases the cohesion and inhibits the flow.

[EN] Continuous reinforced concrete (RC) beams may develop significant plastic rotations to enable the redistribution of bending moments. These rotations occur at plastic hinges, which are subject to high shear forces. The influence of rotations on the shear strength for statically determined beams without shear reinforcement failing in shear after yielding of the flexural reinforcement has already been experimentally verified. However, this influence has not been studied in continuous members with shear reinforcement. An innovative tests system has been specially designed to develop shear failures before and after yielding of the flexural reinforcement in both statically determinate and indeterminate structures. Nine beams (9000 mm long, 250 mm wide, 450 mm high) with a shear reinforcement of phi 8/30 (rho(w) = 0.13%) and different longitudinal reinforcement ratios were tested under different load and support conditions. The shear strength provided by shear reinforcement and that provided by the other mechanisms of resistance (shear strength provided by concrete) for each specimen were calculated based on the critical shear crack width measurements performed by Digital Image Correlation (DIC). Bending rotation and crack rotation along the development length of the critical shear crack were also obtained by DIC. Based on the test results, the shear strength provided by concrete was studied in relation to the bending rotation and the average crack width in reinforced concrete beams with shear reinforcement. It was confirmed that the shear strength provided by concrete decreased with increasing both bending rotations and crack widths. The shear strength values predicted by different design codes (ACI 318-19, Eurocode 2 and Model Code 2010) were compared with the test results, and showed that these formulations did not properly capture the loss of shear strength caused by bending rotation.

[EN] Shear strength of reinforced concrete beams has been extensively studied by many experimental campaigns conducted on simply supported beams. This situation has led to implement empirical design formulations in codes that cannot be representative of other real structures, such as continuous beams. These structures are characterised by the potential development of plastic hinges in areas of maximum shear and by the existence of an inflection point in the shear span. However, very few experimental studies on them have been conducted. In this paper, the shear strength of cantilever and continuous beams with different shear reinforcement ratios is analysed based on the test results of an experimental programme involving 15 beams. Nine beams of 9.00 m and six of 7.00 m with rectangular cross-sections were tested under different load and support conditions, which gave rise to 30 different shear tests (two tests per beam). Three different series were considered according to the shear reinforcement ratio (0%, 0.13% and 0.20%). Apart from traditional instrumentation, such as strain gauges and displacement transducers, Digital Image Correlation was employed to provide accurate displacement measurements. The results showed that the shear strength provided by concrete (different shear-transfer actions from shear reinforcement) decreased as bending rotation increased within both the elastic and plastic ranges of rotations developed in continuous beams. Moreover, this shear strength component was reduced for increasing shear reinforcement ratios. Shear slenderness was redefined for continuous beams that failed in shear after yielding of the tensile reinforcement and redistributing internal forces. The code formulation provided by ACI 318-19, Eurocode 2 and Model Code 2010 was checked against the experimental results, which showed that the iterative formulation that contemplates the M-V interaction considerably improved shear strength predictions from simple formulations.

Applying accurate normal load to a specimen in direct shear tests under constant normal stiffness (CNS) is of importance for the quality of the resulting data, which in turn influences the conclusions. However, deficiencies in the test system give rise to a normal stiffness, here designated as system normal stiffness, which results in deviations between the intended and actual applied normal loads. Aiming to reduce these deviations, this paper presents the effective normal stiffness approach applicable to closed-loop control systems. Validation through direct shear tests indicates a clear influence of the system normal stiffness on the applied normal load (13% for the test system used in this work). The ability of the approach to compensate for this influence is confirmed herein. Moreover, it is demonstrated that the differences between the measured and the nominal normal displacements are established by the normal load increment divided by the system normal stiffness. This further demonstrates the existence of the system normal stiffness. To employ the effective normal stiffness approach, the intended normal stiffness (user defined) and the system normal stiffness must be known. The latter is determined from a calibration curve based on normal loading tests using a stiff test dummy. Finally, a procedure is presented to estimate errors originating from the application of an approximate representation of the system normal stiffness. The approach is shown to effectively reduce the deviations between intended normal loads and the actual applied normal loads., QC 20200701

The rapid development of semiconductor industry in the past decades has reshaped the world tremendously and greatly changed people's lives. Two-dimensional (2D) down-sizing of semiconductor devices following the “Moore's law” for many years is now reaching its boundary conditions of further exponential growth and three-dimensional (3D) fabrication approaches are getting more attention. Next to the IC manufacturing, 3D chip packaging has been playing a more important role nowadays. Much more cost-effective and scalable technologies are being developed. Vertical interconnect via technology such as through-silicon via (TSV), through mold via (TMV), tall Cu pillar (TCP), and vertical wire bonds (VWB) are the key processes in 3D chip packaging. However, they have limitations in cost, reliability, via density, scalability, and aspect ratio. In addition, as the function integration density keeps increasing, not only electrical interconnection but also optical, mechanical, fluidic, and thermal interconnections are needed in the near future. Thus, a low-cost, reliable, high density, scalable, high-aspect-ratio multi-functional advanced through package via technology is highly demanded in the future semiconductor industry. Through-Polymer Via (TPV) is a novel bottom-up vertical through package via technology potentially low-cost process, suitable for high density and high-aspect-ratio via formation, compatible with the various packaging process and suitable for multi-functional applications. The main process of TPV technology consists of the formation of a high-aspect-ratio polymer structure through lithography in combination with subsequent film assisted molding. TPV process works with both spin coating and dry film lamination for applying the polymer material, which is suitable for low-cost wafer-level and panel-level mass production. The process uses thick photosensitive polymer materials, such as SU-8 and SUEX, and the structures are patterned via lithography, which enabl, Electronic Components, Technology and Materials

[EN] Shear strength of reinforced concrete beams has been extensively studied by many experimental campaigns conducted on simply supported beams. This situation has led to implement empirical design formulations in codes that cannot be representative of other real structures, such as continuous beams. These structures are characterised by the potential development of plastic hinges in areas of maximum shear and by the existence of an inflection point in the shear span. However, very few experimental studies on them have been conducted. In this paper, the shear strength of cantilever and continuous beams with different shear reinforcement ratios is analysed based on the test results of an experimental programme involving 15 beams. Nine beams of 9.00 m and six of 7.00 m with rectangular cross-sections were tested under different load and support conditions, which gave rise to 30 different shear tests (two tests per beam). Three different series were considered according to the shear reinforcement ratio (0%, 0.13% and 0.20%). Apart from traditional instrumentation, such as strain gauges and displacement transducers, Digital Image Correlation was employed to provide accurate displacement measurements. The results showed that the shear strength provided by concrete (different shear-transfer actions from shear reinforcement) decreased as bending rotation increased within both the elastic and plastic ranges of rotations developed in continuous beams. Moreover, this shear strength component was reduced for increasing shear reinforcement ratios. Shear slenderness was redefined for continuous beams that failed in shear after yielding of the tensile reinforcement and redistributing internal forces. The code formulation provided by ACI 318-19, Eurocode 2 and Model Code 2010 was checked against the experimental results, which showed that the iterative formulation that contemplates the M-V interaction considerably improved shear strength predictions from simple formulations.

[EN] Continuous reinforced concrete (RC) beams may develop significant plastic rotations to enable the redistribution of bending moments. These rotations occur at plastic hinges, which are subject to high shear forces. The influence of rotations on the shear strength for statically determined beams without shear reinforcement failing in shear after yielding of the flexural reinforcement has already been experimentally verified. However, this influence has not been studied in continuous members with shear reinforcement. An innovative tests system has been specially designed to develop shear failures before and after yielding of the flexural reinforcement in both statically determinate and indeterminate structures. Nine beams (9000 mm long, 250 mm wide, 450 mm high) with a shear reinforcement of phi 8/30 (rho(w) = 0.13%) and different longitudinal reinforcement ratios were tested under different load and support conditions. The shear strength provided by shear reinforcement and that provided by the other mechanisms of resistance (shear strength provided by concrete) for each specimen were calculated based on the critical shear crack width measurements performed by Digital Image Correlation (DIC). Bending rotation and crack rotation along the development length of the critical shear crack were also obtained by DIC. Based on the test results, the shear strength provided by concrete was studied in relation to the bending rotation and the average crack width in reinforced concrete beams with shear reinforcement. It was confirmed that the shear strength provided by concrete decreased with increasing both bending rotations and crack widths. The shear strength values predicted by different design codes (ACI 318-19, Eurocode 2 and Model Code 2010) were compared with the test results, and showed that these formulations did not properly capture the loss of shear strength caused by bending rotation.

The rapid development of semiconductor industry in the past decades has reshaped the world tremendously and greatly changed people's lives. Two-dimensional (2D) down-sizing of semiconductor devices following the “Moore's law” for many years is now reaching its boundary conditions of further exponential growth and three-dimensional (3D) fabrication approaches are getting more attention. Next to the IC manufacturing, 3D chip packaging has been playing a more important role nowadays. Much more cost-effective and scalable technologies are being developed. Vertical interconnect via technology such as through-silicon via (TSV), through mold via (TMV), tall Cu pillar (TCP), and vertical wire bonds (VWB) are the key processes in 3D chip packaging. However, they have limitations in cost, reliability, via density, scalability, and aspect ratio. In addition, as the function integration density keeps increasing, not only electrical interconnection but also optical, mechanical, fluidic, and thermal interconnections are needed in the near future. Thus, a low-cost, reliable, high density, scalable, high-aspect-ratio multi-functional advanced through package via technology is highly demanded in the future semiconductor industry. Through-Polymer Via (TPV) is a novel bottom-up vertical through package via technology potentially low-cost process, suitable for high density and high-aspect-ratio via formation, compatible with the various packaging process and suitable for multi-functional applications. The main process of TPV technology consists of the formation of a high-aspect-ratio polymer structure through lithography in combination with subsequent film assisted molding. TPV process works with both spin coating and dry film lamination for applying the polymer material, which is suitable for low-cost wafer-level and panel-level mass production. The process uses thick photosensitive polymer materials, such as SU-8 and SUEX, and the structures are patterned via lithography, which enabl, Electronic Components, Technology and Materials

The rapid development of semiconductor industry in the past decades has reshaped the world tremendously and greatly changed people's lives. Two-dimensional (2D) down-sizing of semiconductor devices following the “Moore's law” for many years is now reaching its boundary conditions of further exponential growth and three-dimensional (3D) fabrication approaches are getting more attention. Next to the IC manufacturing, 3D chip packaging has been playing a more important role nowadays. Much more cost-effective and scalable technologies are being developed. Vertical interconnect via technology such as through-silicon via (TSV), through mold via (TMV), tall Cu pillar (TCP), and vertical wire bonds (VWB) are the key processes in 3D chip packaging. However, they have limitations in cost, reliability, via density, scalability, and aspect ratio. In addition, as the function integration density keeps increasing, not only electrical interconnection but also optical, mechanical, fluidic, and thermal interconnections are needed in the near future. Thus, a low-cost, reliable, high density, scalable, high-aspect-ratio multi-functional advanced through package via technology is highly demanded in the future semiconductor industry. Through-Polymer Via (TPV) is a novel bottom-up vertical through package via technology potentially low-cost process, suitable for high density and high-aspect-ratio via formation, compatible with the various packaging process and suitable for multi-functional applications. The main process of TPV technology consists of the formation of a high-aspect-ratio polymer structure through lithography in combination with subsequent film assisted molding. TPV process works with both spin coating and dry film lamination for applying the polymer material, which is suitable for low-cost wafer-level and panel-level mass production. The process uses thick photosensitive polymer materials, such as SU-8 and SUEX, and the structures are patterned via lithography, which enabl, Electronic Components, Technology and Materials

In-plane strength and constitutive properties of composite materials is known as crucial problems. Although, several studies have been made for obtaining the in-plane mode II properties, the common test fixtures are blind in confrontation of shear zone. Furthermore, toughening mechanisms and consequently mode II fracture toughness cannot be evaluated, precisely. Also, proposing the convenient configuration of shear test fixture increase the accuracy of evaluation for the shear-zone energy dissipation, especially in orthotropic materials. Hence in the present research, a novel shear fixture configuration is proposed based on Iosipesque structural modification. Hereof, some arbitrary composite materials (e.g. graphite/epoxy and wood) were studies on the basis of DOE and E-691 ASTM. Furthermore, as the numerical method for indicating the comparison of the uniform and non-uniform shear stress distribution in the modified and common shear test fixture, a statistical procedure is used based on ASTM standard in addition to FEM analysis. The obtained results reveal that applying major amendments through the new scheme of the shear test fixture, would provide a remarkable precision and a reasonable estimation of the shear strength in comparison with the previous Iosipesque experiments.

Friction welding of wood is a joining technique that has the advantage of being a fast process that does not require the utilization of additional material such as mechanical fastener or synthetic adhesives. The water resistance, as well as shear strength of the welded joints of birch (Betula pendula) at 24 and 48 hours water-soaking time were investigated. Additionally, an X-ray Computed Tomography (CT) scanning was used to monitor the density profile of the welded bond-line. The LT-surfaces of specimens measuring 200 × 20 × 20 mm (L × T × R) were welded two-by-two. The results showed that the shear strength decreased slightly with increasing immersion time. The reduction of the shear strength caused by immersion in water for 24h and 48h compared to non-soaked specimens, were 60% and 79%, respectively. The X-ray CT-scanning results revealed that the average density of the Birch (530 kg/m3) increased to 700 kg/m3 in the welded bond line, i.e. the wood also undergo densification during the welding process., Finansiär: Scientific and Technological Research Council of Turkey (TUBITAK- 2219/BIDEB, 2019)

Aquest estudi busca estudiar la interacció dels diferents elements de les estructures híbrides a un nivell mecànic-resistent, enfocant-se en el material compost de Carbon Fiber Reinforced Polymer (CFRP) i formigó. Es fa un estudi del comportament del formigó amb una xapa de CFRP, on la xapa de CFRP es col·locada per l’estudi com a material de reforç estructural, estudiant diferents casos d’elements d’adherència que es troben sobre la superfície del CFRP. Es documenta el procés complet de fabricació i condicionament dels espècimens a assajar, tenint en tot moment en compte les mesures de seguretat necessàries per a la realització de cada tasca. Es sotmeten els espècimens a esforços de tallant i de flexió per determinar quin elements de nexe milloren les seves propietats i quin es el canvi en el comportament de l’estructura. S’intenta aproximar el comportament inicial de l’estructura híbrida a flexió mitjançant el teorema de l’homogeneïtzació i al punt de trencament mitjançant una suposició de la distribució d’esforços. Un cop determinats els elements de nexe que donen millors propietats, es duu a terme la fabricació d’un prototip de dipòsit d’aigua per comprovar la possible industrialització de la tecnologia

Friction welding of wood is a joining technique that has the advantage of being a fast process that does not require the utilization of additional material such as mechanical fastener or synthetic adhesives. The water resistance, as well as shear strength of the welded joints of birch (Betula pendula) at 24 and 48 hours water-soaking time were investigated. Additionally, an X-ray Computed Tomography (CT) scanning was used to monitor the density profile of the welded bond-line. The LT-surfaces of specimens measuring 200 × 20 × 20 mm (L × T × R) were welded two-by-two. The results showed that the shear strength decreased slightly with increasing immersion time. The reduction of the shear strength caused by immersion in water for 24h and 48h compared to non-soaked specimens, were 60% and 79%, respectively. The X-ray CT-scanning results revealed that the average density of the Birch (530 kg/m3) increased to 700 kg/m3 in the welded bond line, i.e. the wood also undergo densification during the welding process., Finansiär: Scientific and Technological Research Council of Turkey (TUBITAK- 2219/BIDEB, 2019)

This study demonstrates a new constant-volume shear test configuration to analyze the stresses in powder beds and evaluate powder flowability. A novel cylindrical shear cell geometry and load cell arrangement allowed precise measurement of the normal stress acting on the shear planes of the powder beds. The stress transmission ratio between the top and shear planes decreased with increasing ratio of the powder bed height in the upper section of the shear cell to the shear cell diameter. This was due to friction between the powder bed and the side wall of the upper section of the shear cell. Using the measured values of the normal stress on the shear planes, the effects of the powder bed height and shear cell diameter were eliminated from the data. In addition, to evaluate the shear properties of the powder beds, the powder yield locus, consolidation yield locus, critical state line, shear cohesion, and void fraction were obtained from a single shear test. The powder yield locus data were used to obtain flow functions.

The bond shear strength between masonry units and mortar is the weakest link in a masonry wall. Different material tests have been developed in order to characterize this bond behaviour. The objective of this study is to evaluate three common test setups through non-linear finite element analysis. The simulation method is based on our recent development of cohesive elements, which allows for the first time to fully capture the force-deformation characteristic of shear tests in 3D from the onset of loading until the residual shear strength and to retrieve typical shear failure modes observed in experiments. This study provides new insights into our understanding and interpretation of such shear tests: (1) elastic analysis, which has been widely used in the past, does not yield a stress distribution that is representative of the stress distribution at maximum resistance; (2) while friction coefficient is well estimated (the error is less than 10%), the local cohesion is underestimated by all three test setups of which the error lies between 13 and 32%; (3) the randomness of the material properties leads to a further underestimation of the mean value of the local cohesion; (4) differences in the material properties of the two joints of the triplet test units do not jeopardize the applicability of this test setup and estimations of the mean properties are obtained with similar reliability as for couplet tests.

The bond shear strength between masonry units and mortar is the weakest link in a masonry wall. Different material tests have been developed in order to characterize this bond behaviour. The objective of this study is to evaluate three common test setups through non-linear finite element analysis. The simulation method is based on our recent development of cohesive elements, which allows for the first time to fully capture the force-deformation characteristic of shear tests in 3D from the onset of loading until the residual shear strength and to retrieve typical shear failure modes observed in experiments. This study provides new insights into our understanding and interpretation of such shear tests: (1) elastic analysis, which has been widely used in the past, does not yield a stress distribution that is representative of the stress distribution at maximum resistance; (2) while friction coefficient is well estimated (the error is less than 10%), the local cohesion is underestimated by all three test setups of which the error lies between 13 and 32%; (3) the randomness of the material properties leads to a further underestimation of the mean value of the local cohesion; (4) differences in the material properties of the two joints of the triplet test units do not jeopardize the applicability of this test setup and estimations of the mean properties are obtained with similar reliability as for couplet tests.

Consulta en la Biblioteca ETSI Industriales (Riunet), [EN] Heavy forestry machines have great immediate effect on soil properties. This increases the interest to develop approaches that help understanding better the interaction between the forest machines and the terrain and consequently develop the forwarders to be gentle to the environment. The most predominant indications of soil disturbances caused by harvesting are mainly rutting and soil compaction. It is critical to understand and evaluate these damages to be able to protect the remaining trees and improve their tree growth rate. Comprehending the bearing capacity of the soil and the interaction between tire and soil are the key issues to develop forest machines that preserve the terrain. The first step to accomplish this goal is to compare the rut depth theoretical data from empirical models with the rut depth data from a full scale field test, the models suitable to predict rut depth is descripted. Tree roots reinforce the forest floor and significantly increase the bearing capacity of the soil. The contribution from root layer to the soil bearing capacity depends on the number, diameter, orientation of the roots and their mechanical properties. To improve the root tensile strength model, a root bending and stretching laboratory test has been carry out and compared with FEM-based results. The existing Valmet 860.3 Adams MBS model is finally used to study the suitability of the model to predict rut depth. A comparison between all methods to predict rut depth is also shown.

Consulta en la Biblioteca ETSI Industriales (Riunet), [EN] Heavy forestry machines have great immediate effect on soil properties. This increases the interest to develop approaches that help understanding better the interaction between the forest machines and the terrain and consequently develop the forwarders to be gentle to the environment. The most predominant indications of soil disturbances caused by harvesting are mainly rutting and soil compaction. It is critical to understand and evaluate these damages to be able to protect the remaining trees and improve their tree growth rate. Comprehending the bearing capacity of the soil and the interaction between tire and soil are the key issues to develop forest machines that preserve the terrain. The first step to accomplish this goal is to compare the rut depth theoretical data from empirical models with the rut depth data from a full scale field test, the models suitable to predict rut depth is descripted. Tree roots reinforce the forest floor and significantly increase the bearing capacity of the soil. The contribution from root layer to the soil bearing capacity depends on the number, diameter, orientation of the roots and their mechanical properties. To improve the root tensile strength model, a root bending and stretching laboratory test has been carry out and compared with FEM-based results. The existing Valmet 860.3 Adams MBS model is finally used to study the suitability of the model to predict rut depth. A comparison between all methods to predict rut depth is also shown.

Consulta en la Biblioteca ETSI Industriales (Riunet), [EN] Heavy forestry machines have great immediate effect on soil properties. This increases the interest to develop approaches that help understanding better the interaction between the forest machines and the terrain and consequently develop the forwarders to be gentle to the environment. The most predominant indications of soil disturbances caused by harvesting are mainly rutting and soil compaction. It is critical to understand and evaluate these damages to be able to protect the remaining trees and improve their tree growth rate. Comprehending the bearing capacity of the soil and the interaction between tire and soil are the key issues to develop forest machines that preserve the terrain. The first step to accomplish this goal is to compare the rut depth theoretical data from empirical models with the rut depth data from a full scale field test, the models suitable to predict rut depth is descripted. Tree roots reinforce the forest floor and significantly increase the bearing capacity of the soil. The contribution from root layer to the soil bearing capacity depends on the number, diameter, orientation of the roots and their mechanical properties. To improve the root tensile strength model, a root bending and stretching laboratory test has been carry out and compared with FEM-based results. The existing Valmet 860.3 Adams MBS model is finally used to study the suitability of the model to predict rut depth. A comparison between all methods to predict rut depth is also shown.

Heavy forestry machines have great immediate effect on soil properties. This increases the interest to develop approaches that help understanding better the interaction between the forest machines and the terrain and consequently develop the forwarders to be gentle to the environment. The most predominant indications of soil disturbances caused by harvesting are mainly rutting and soil compaction. It is critical to understand and evaluate these damages to be able to protect the remaining trees and improve their tree growth rate. Comprehending the bearing capacity of the soil and the interaction between tire and soil are the key issues to develop forest machines that preserve the terrain. The first step to accomplish this goal is to compare the rut depth theoretical data from empirical models with the rut depth data from a full scale field test, the models suitable to predict rut depth is descripted. Tree roots reinforce the forest floor and significantly increase the bearing capacity of the soil. The contribution from root layer to the soil bearing capacity depends on the number, diameter, orientation of the roots and their mechanical properties. To improve the root tensile strength model, a root bending and stretching laboratory test has been carry out and compared with FEM-based results. The existing Valmet 860. 3 Adams MBS model is finally used to study the suitability of the model to predict rut depth. A comparison between several existing methods to predict rut depth is also shown., Tunga skogsmaskiner har stor omedelbar effekt på markens egenskaper. Detta ökar intresset för att utveckla strategier som underlättar förståelsen av samverkan mellan skogsmaskiner och terrängen och därmed utveckla framdrivning av dessa maskiner som är skonsam mot miljön. De dominerande indikationerna på markstörningar orsakade av hjulbaserade skogsmaskiner är främst spårbildning och jordkompaktering. Det är viktigt att förstå och utvärdera dessa skador för att kunna skydda de kvarvarande träden och förbättra deras tillväxt. Att förstå markens bärighet och samspelet mellan däck och mark är de viktigaste frågorna för att utveckla skogsmaskiner som skonar terrängen. Det första steget för att uppnå detta mål är att jämföra spårdjup vilka är framtagna med empiriska modeller med data för spårdjup från ett fullskaligt fälttest, där de modeller som lämpar sig för att förutsäga spårdjup är beskrivna. Trädrötter förstärker skogsmarken och ökar avsevärt jordens bärighet. Bidraget från rotlagret till jordens bärförmåga beror på antalet rötter, deras diameter samt rötternas orientering och deras mekaniska egenskaper. För att förbättra modellen för rötternas mekaniska egenskaper har rotböjning och rottöjning studerats i ett laboratorietest och vidare jämförts med FEM-baserade resultat. Den befintliga MBS modellen av skotaren Valmet 860.3 har slutligen används för att studera lämpligheten av modellen för att förutsäga spårdjup. En jämförelse mellan flera olika metoder för att förutsäga spårdjup visas också.

Heavy forestry machines have great immediate effect on soil properties. This increases the interest to develop approaches that help understanding better the interaction between the forest machines and the terrain and consequently develop the forwarders to be gentle to the environment. The most predominant indications of soil disturbances caused by harvesting are mainly rutting and soil compaction. It is critical to understand and evaluate these damages to be able to protect the remaining trees and improve their tree growth rate. Comprehending the bearing capacity of the soil and the interaction between tire and soil are the key issues to develop forest machines that preserve the terrain. The first step to accomplish this goal is to compare the rut depth theoretical data from empirical models with the rut depth data from a full scale field test, the models suitable to predict rut depth is descripted. Tree roots reinforce the forest floor and significantly increase the bearing capacity of the soil. The contribution from root layer to the soil bearing capacity depends on the number, diameter, orientation of the roots and their mechanical properties. To improve the root tensile strength model, a root bending and stretching laboratory test has been carry out and compared with FEM-based results. The existing Valmet 860. 3 Adams MBS model is finally used to study the suitability of the model to predict rut depth. A comparison between several existing methods to predict rut depth is also shown., Tunga skogsmaskiner har stor omedelbar effekt på markens egenskaper. Detta ökar intresset för att utveckla strategier som underlättar förståelsen av samverkan mellan skogsmaskiner och terrängen och därmed utveckla framdrivning av dessa maskiner som är skonsam mot miljön. De dominerande indikationerna på markstörningar orsakade av hjulbaserade skogsmaskiner är främst spårbildning och jordkompaktering. Det är viktigt att förstå och utvärdera dessa skador för att kunna skydda de kvarvarande träden och förbättra deras tillväxt. Att förstå markens bärighet och samspelet mellan däck och mark är de viktigaste frågorna för att utveckla skogsmaskiner som skonar terrängen. Det första steget för att uppnå detta mål är att jämföra spårdjup vilka är framtagna med empiriska modeller med data för spårdjup från ett fullskaligt fälttest, där de modeller som lämpar sig för att förutsäga spårdjup är beskrivna. Trädrötter förstärker skogsmarken och ökar avsevärt jordens bärighet. Bidraget från rotlagret till jordens bärförmåga beror på antalet rötter, deras diameter samt rötternas orientering och deras mekaniska egenskaper. För att förbättra modellen för rötternas mekaniska egenskaper har rotböjning och rottöjning studerats i ett laboratorietest och vidare jämförts med FEM-baserade resultat. Den befintliga MBS modellen av skotaren Valmet 860.3 har slutligen används för att studera lämpligheten av modellen för att förutsäga spårdjup. En jämförelse mellan flera olika metoder för att förutsäga spårdjup visas också.

The final publication is available at Springer via http://dx.doi.org/10.1617/s11527-014-0340-5, The shear strength of one-way slabs is studied in this paper via an experimental program performed by the authors and the analysis of a shear test database. The experimental program, in which six slabs and three beams divided into two series were tested, was developed to study the influence of the slab width, the longitudinal reinforcement spacing and the bottom transverse reinforcement on the shear response of one-way slabs. The results showed that the width and the bottom transverse reinforcement do not significantly affect the shear response of the slab. The shear failure surface depends on the longitudinal reinforcement spacing because a three-dimensional resisting mechanism formed as a result of large bar spacing. A database of 79 tests on slabs was analysed to study in depth the influence of these parameters on the shear strength of one-way slabs. Finally, different shear procedures were applied to the database to evaluate their reliability to predict the shear strength., Peer Reviewed, Postprint (author's final draft)

The frozen soil-structure interface is the key connecting component between structures and the soil in the permafrost regions. The soil-structure interface is usually subjected to seismic or wind loadings; consequently the cyclic shear properties of the interface are the key parameters of concern when considering the safety and durability of the structures in these permafrost regions. In this paper we present the results of measuring and analyzing the cyclic shear properties of an artificially frozen soil-structure interface; the experimental work being conducted on our self-developed, large-scale multi-functional direct shear apparatus (DDJ-1). These direct shear tests were conducted under conditions of constant normal stiffness, having a specific initial value for normal stresses (either 300, 500, or 700. kPa), and at a constant frozen temperature (i.e. -. 6, -. 10, or -. 14. °C) or a rising temperature (from -. 14. °C to -. 2. °C). Their cyclic shear stress and normal displacement were measured in 30. cycles for each of the constant frozen temperature settings, and in 13.25. cycles for the rising temperature. These test results show that: (1) The maximum shear stress is observed in the first cycle. This maximum shear stress is higher for lower frozen temperature and higher initial normal stress. Furthermore, the internal friction angle of the frozen soil-structure interface decreases with shear cycle and higher frozen temperature. (2) Under constant frozen temperature, the rates of increase of the normal displacement and normal stress slow down with cyclic loading time. However, these rates of increase are fast at the beginning, slow down, and then speed up again under the rising temperature. (3) The reversible normal displacement, expressed by the peak-to-trough distance of normal displacement, linearly increases with the initial normal stress when the frozen temperature is constant.

Residual soils by their formation process have special characteristics that are not characterized in traditional soil mechanics devoted to sedimentary soils. The weathering processes according to the cycles of exposure to those who are exposed have variations in composition and mechanical behavior. Residual soils from Amphibolite rock located in the valley of St. Nicholas, near the city of Medellin have been recovered and tested. The variation of the speed versus shear strength of the undrained shear strength was evaluated by conducting direct shear tests on undisturbed samples under Unconsolidated and Undrained conditions, soil samples were recovered using shelby thin-walled tubes, graphs of the variation of the shear strength, cohesion and friction angle versus speed and their impact on design., Os solos residuais, devido aos seus processos de formação, tem uma caraterísticas especiais que não estão caraterizadas dentro da mecânica de solos tradicionais dedicada aos solos sedimentários. Os processos de meteorizarão segundo os ciclos de exposição aos que estão expostos apresentam variações na sua composição e comportamento mecânico. Solos residuais de anfibolito localizados no vale de San Nicolás, perto a cidade de Medellín foram recuperados e ensaiados. A variação da velocidade do ensaio de corte contra a resistência ao corte não drenado foram avaliados mediante a realização de ensaios de corte UU sobre amostras inalteradas recuperadas mediante a utilização de tubos shelby de parede fina, apresentam-se as gráficas de variação do esforço cortante, a coesão e ângulo de atrito contra a velocidade e a sua incidência em desenho, apresentam-se as conclusões e recomendações ao final., Los suelos residuales por su proceso de formación tienen unas características especiales que no están caracterizados dentro de la mecánica de suelos tradicional dedicada a los suelos sedimentarios. El proceso de meteorización según los ciclos de exposición a los que sean expuestos presentan variaciones en su composición y comportamiento mecánico. Suelos residuales de anfibolita localizados en el Valle de San Nicolás, cerca de la ciudad de Medellín han sido recuperados y ensayados. La variación de la velocidad del ensayo de corte versus la resistencia al corte no drenada ha sido evaluada mediante la realización de ensayos de corte UU sobre muestras inalteradas recuperadas mediante la utilización de Tubos Shelby de pared delgada, se presentan las gráficas de variación del esfuerzo cortante, la cohesión y ángulo de fricción versus la velocidad y su incidencia en el diseño.

Residual soils by their formation process have special characteristics that are not characterized in traditional soil mechanics devoted to sedimentary soils. The weathering processes according to the cycles of exposure to those who are exposed have variations in composition and mechanical behavior. Residual soils from Amphibolite rock located in the valley of St. Nicholas, near the city of Medellin have been recovered and tested. The variation of the speed versus shear strength of the undrained shear strength was evaluated by conducting direct shear tests on undisturbed samples under Unconsolidated and Undrained conditions, soil samples were recovered using shelby thin-walled tubes, graphs of the variation of the shear strength, cohesion and friction angle versus speed and their impact on design., Os solos residuais, devido aos seus processos de formação, tem uma caraterísticas especiais que não estão caraterizadas dentro da mecânica de solos tradicionais dedicada aos solos sedimentários. Os processos de meteorizarão segundo os ciclos de exposição aos que estão expostos apresentam variações na sua composição e comportamento mecânico. Solos residuais de anfibolito localizados no vale de San Nicolás, perto a cidade de Medellín foram recuperados e ensaiados. A variação da velocidade do ensaio de corte contra a resistência ao corte não drenado foram avaliados mediante a realização de ensaios de corte UU sobre amostras inalteradas recuperadas mediante a utilização de tubos shelby de parede fina, apresentam-se as gráficas de variação do esforço cortante, a coesão e ângulo de atrito contra a velocidade e a sua incidência em desenho, apresentam-se as conclusões e recomendações ao final., Los suelos residuales por su proceso de formación tienen unas características especiales que no están caracterizados dentro de la mecánica de suelos tradicional dedicada a los suelos sedimentarios. El proceso de meteorización según los ciclos de exposición a los que sean expuestos presentan variaciones en su composición y comportamiento mecánico. Suelos residuales de anfibolita localizados en el Valle de San Nicolás, cerca de la ciudad de Medellín han sido recuperados y ensayados. La variación de la velocidad del ensayo de corte versus la resistencia al corte no drenada ha sido evaluada mediante la realización de ensayos de corte UU sobre muestras inalteradas recuperadas mediante la utilización de Tubos Shelby de pared delgada, se presentan las gráficas de variación del esfuerzo cortante, la cohesión y ángulo de fricción versus la velocidad y su incidencia en el diseño.

The purpose of this master thesis has been to investigate the possibility to increase the damping capacity of shear walls with the use of glue in combination with nails. It has been done with experiment and with FE-simulations. The first experimental part is tensile tests of four different glue types which have been analyzed to get material data. The second experimental part is analysis of glued-nail joint in shear test. FE-simulations of glued-nail joints are finally done in Abaqus/CAE. The experiments in shear tests of glued-nail joints showed that two glues failed and could not be used for further analysis. The two other glues had an increase in damping capacity compared with results from nail joint. Further FE-simulations of glued-nailed joints have to be done in order to calibrate the FE-model with the results of glued-nailed joints in shear tests. The uncertainty is found in the material properties of the glue, experimental test data was not adequate. The conclusion is that glued-nail joints can increase the damping capacity in shear walls., Damping capacity, shear wall, hysteresis, shear test, finite element method, Abaqus/CAE

The purpose of this master thesis has been to investigate the possibility to increase the damping capacity of shear walls with the use of glue in combination with nails. It has been done with experiment and with FE-simulations. The first experimental part is tensile tests of four different glue types which have been analyzed to get material data. The second experimental part is analysis of glued-nail joint in shear test. FE-simulations of glued-nail joints are finally done in Abaqus/CAE. The experiments in shear tests of glued-nail joints showed that two glues failed and could not be used for further analysis. The two other glues had an increase in damping capacity compared with results from nail joint. Further FE-simulations of glued-nailed joints have to be done in order to calibrate the FE-model with the results of glued-nailed joints in shear tests. The uncertainty is found in the material properties of the glue, experimental test data was not adequate. The conclusion is that glued-nail joints can increase the damping capacity in shear walls., Damping capacity, shear wall, hysteresis, shear test, finite element method, Abaqus/CAE

In this work, the notched shear strength test (NST) has been further improved. In order to simplify and accelerate the testing procedure, the notches with declined slopes were used. With the proposed procedure, the shear strength profile in the thickness direction of a paperboard can be measured using one sheet only. By using the test setup, the dependency of shear zone length on shear strength was investigated. Experimental results show that both the measured shear strength values as well as the shear strength profile varied significantly with different shear zone length. Longer shear zone gave lower shear strength values and flatter profiles, while a shorter shear zone gave higher strength values and more pronounced shear strength profiles that better followed the paperboard ply structure., QC 20110317

This paper presents an evaluation of the constitutive behaviour, including plastic anisotropy and mixed isotropic-kinematic hardening of two high strength steels, Docol 600DP and Docol 1200M, during strain path changes. A series of tensile and shear tests was performed on both virgin and pre-strained materials. The initial anisotropy and work hardening parameters were obtained from tensile tests, shear tests and a bulge test of the virgin material, whereas the kinematic hardening parameters were identified by comparing numerical predictions to experimental results related to the pre-strained materials. Numerical predictions using the obtained parameters agree well with the experimental results, both in the case of proportional, and under non-proportional strain paths.

The use of high strength concrete (HSC) in columns has become more frequent since a substantial reduction of the cross-section is obtained, meaning that slenderness increases for the same axial load and length, producing higher second order effects. However, the experimental tests in the literature of reinforced concrete columns subjected to axial load and lateral force focus on shear span ratios, according to Eurocode 2 (2004), clause 5.6.3., (M/(V·h)) lower than 6.5. This gap in the literature limits technological development for the construction of these structural elements. This paper presents 44 experimental tests on reinforced concrete columns subjected to constant axial load and monotonic lateral force. The aim of this is to gain greater knowledge of the types of elements which will also be of use in calibrating the numerical models and validating the simplified methods. The test parameters are strength of concrete (normal- and high-strength concrete), shear span ratio, axial load level and longitudinal and transversal reinforcement ratios. The strength and deformation of the columns were studied, and an analysis of the simplified methods from Eurocode 2 (2004) and ACI-318 (2008) concluded that both are very conservative. © 2011 Elsevier Ltd.

[EN] Objective: The purpose of this study was to determine whether the bond of veneering porcelain to a ceramic core in bilayered ceramics was similar to that of the metal ceramic control of well known behaviour. Study design: Six groups of nine specimens each were fabricated, whose dimensions were 15 mm long and 8 mm in diameter at the core, and 2 mm long and 8 mm in diameter for the veneer. The groups were GR. 1 (control group): CrNi alloy/d.SIGN (Ivoclar), GR. 2: IPS e.maxPress/IPS e.maxCeram (Ivoclar), GR. 3: IPS e.maxZirCad/IPS e.maxZirPress (Ivoclar), GR. 4: IPS e.maxZirCad/IPS e.maxCeram (Ivoclar), GR. 5: Lava Frame (3M ESPE)/Lava Ceram (3M ESPE) and GR. 6: Lava Frame (3M ESPE)/IPS e.maxCeram (Ivoclar). A shear strength test was used in all samples with a universal testing machine. The chosen crosshead speed was of 0.50 mm/min. The obtained results were analyzed using a one way analysis of variance test (ANOVA) to determine whether significant differences existed between the groups (p<0.05). A Student Newman-Keuls multiple comparisons test was used. Results: GR. 1: 13.45 MPa, GR. 2: 24.20 MPa, GR. 3: 12.70 MPa, GR. 4: 7.86 MPa, GR. 5: 10.20 Mpa and GR. 6: 4.62 Mpa. Conclusions: The bond strength of group 1 (control) was similar to groups 3 and 5. Group 2, whose core and veneer are both porcelains with a similar chemical composition, with silica as their main component, achieved the best adhesive results between both porcelains. The technique on zirconia cores that showed the higher results was the pressed technique. The lowest results were for the group using porcelains from different manufacturers.

[EN] Objective: The purpose of this study was to determine whether the bond of veneering porcelain to a ceramic core in bilayered ceramics was similar to that of the metal ceramic control of well known behaviour. Study design: Six groups of nine specimens each were fabricated, whose dimensions were 15 mm long and 8 mm in diameter at the core, and 2 mm long and 8 mm in diameter for the veneer. The groups were GR. 1 (control group): CrNi alloy/d.SIGN (Ivoclar), GR. 2: IPS e.maxPress/IPS e.maxCeram (Ivoclar), GR. 3: IPS e.maxZirCad/IPS e.maxZirPress (Ivoclar), GR. 4: IPS e.maxZirCad/IPS e.maxCeram (Ivoclar), GR. 5: Lava Frame (3M ESPE)/Lava Ceram (3M ESPE) and GR. 6: Lava Frame (3M ESPE)/IPS e.maxCeram (Ivoclar). A shear strength test was used in all samples with a universal testing machine. The chosen crosshead speed was of 0.50 mm/min. The obtained results were analyzed using a one way analysis of variance test (ANOVA) to determine whether significant differences existed between the groups (p<0.05). A Student Newman-Keuls multiple comparisons test was used. Results: GR. 1: 13.45 MPa, GR. 2: 24.20 MPa, GR. 3: 12.70 MPa, GR. 4: 7.86 MPa, GR. 5: 10.20 Mpa and GR. 6: 4.62 Mpa. Conclusions: The bond strength of group 1 (control) was similar to groups 3 and 5. Group 2, whose core and veneer are both porcelains with a similar chemical composition, with silica as their main component, achieved the best adhesive results between both porcelains. The technique on zirconia cores that showed the higher results was the pressed technique. The lowest results were for the group using porcelains from different manufacturers.

Civil Engineering and Geosciences

Civil Engineering and Geosciences