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Light Timer Frame Walls are made of solid timber elements and are usually fire protected by other materials. This investigation determines the residual load bearing capacity of Light Timber Frame Walls for fire rating periods of 30, 60, 90 and 120 min. The timber frame is made with 3 studs and 2 tracks, using two different fire protection levels (one and two gypsum layers). The computational model includes the thermal analysis under standard fire, including all types of materials and a sequential mechanical analysis with incremental load applied for each fire rating periods, applied just for the load bearing material. Nonlinear solution methods are used with small tolerance values for solution convergence, to determine the correct temperature and displacement fields. The thermal and the mechanical properties are considered temperature dependent. The mechanical analysis considers large displacement behaviour, and the charring effect of wood is included by the reduction of the stiffness and strength of the timber. The results show that the load bearing capacity decreases with the fire exposure time. A new proposal is presented between the load bearing capacity and the fire rating and finally the char layer is compared with the current and future version of Eurocode 5, part 1.2. info:eu-repo/semantics/publishedVersion

This work presents the results of three connection types in double-shear with dowel fasteners, using the simplified equations from the Eurocode 5. All design parameters were established and compared using three different wood strength and density properties, which constitute the members connections. Eighty-one connections were obtained, allowing to conclude about the number of fasteners needed to the applied tensile load. An increase in the number of dowels was obtained with the increased applied tensile load, lower dowel diameter, lower wood density, and lower strength material in all connection types in the study. The design characteristic load-carrying capacity per shear plane and fastener also decrease with the previously considered parameters.

Multiple bone metastases management requires pain relief and mechanical stability to achieve functional improvement. Inducing tumour cell necrosis is important for local tumour control. A two dimensional thermal and transient numerical model based on finite element method was built to predict the temperature distribution produced by cement polymerization when mimicking a femoral lytic lesion. The bone cement filled the metastatic lesion and titanium, or CF/PEEK intramedullary nail was used. Additionally, two different cement types were compared. Cement A has low viscosity and cement B high viscosity. The titanium intramedullary nail has shown to be the best heat conductor. Significant thermal necrosis occurs with a thin or thick cement amount, and either with low or high viscosity cement types. When choosing to optimize this synergistic effect, a titanium intramedullary nail and cement A induce the largest necrotic area. The results play a role in the multidisciplinary management of long bone metastases.

Some analytical methods are available for temperature evaluation in solid bodies. These methods can be used due to their simplicity and good results. The main goal of this work is to present the temperature calculation in different cross‐sections of structural hot‐rolled steel profiles (IPE, HEM, L, and UAP) using the lumped capacitance method and the simplified equation from Eurocode 3. The basis of the lumped capacitance method is that the temperature of the solid body is uniform at any given time instant during a heat transient process. The profiles were studied, subjected to the fire action according to the nominal temperature–time curves (standard temperature‐time curve ISO 834, external fire curve, and hydrocarbon fire curve). The obtained results allow verifying the agreement between the two methodologies and the influence in the temperature field due to the use of different nominal fire curves. This finding enables us to conclude that the lumped capacitance method is accurate and could be easily applied. info:eu-repo/semantics/publishedVersion

The main objective of this work is to compare the fire resistance between wood-steel-wood (W-S-W) and wood-wood-wood (W-W-W) connections, both joined by steel dowel fasteners, in double shear. The analytical and design procedures follow simplified equations presented in Eurocode 5, part 1-1 and 1-2. A computational methodology, based on finite element method, was also implemented to produce two dimensional thermal simulations, which permits to verify the heating effect through the dowels fasteners or steel elements through the connection in study. Different cross-sections will be identified, considered as the most relevant parts, to compare the temperature distribution in the studied connections. According to the fire exposure, a thermal and transient effect will happen and a char-layer appearing in the exposure side of the connections. The measured quantity of the charred area permits to identify the lost structural material in the studied cross-sections. The charring rate will calculate and compared with the constant value proposed by the Eurocode 5, part 1-2. There are typical values for the charring rate of wood between 0.5-1.0mm/min according to Eurocode 5, part 1-2. However, as a general conclusion and additional information to help designers and professionals, the number of fasteners increases with the applied load, lower dowels diameters have higher effect in the number of fasteners, at fire exposure the steel fasteners bring the heat to inside the connections, and different wood densities affect the thermal behaviour and the charring rate evolution. The charring rate permits to quantify the lost layer thickness and the fire resistance of the connection, dependent on the chosen material density.

Proteomics has been recently introduced in aquaculture research, and more methodological studies are needed to improve the quality of proteomics studies. Therefore, this work aims to compare three sample preparation methods for shotgun LC–MS/MS proteomics using tissues of two aquaculture species: liver of turbot Scophthalmus maximus and hepatopancreas of Mediterranean mussel Mytilus galloprovincialis. We compared the three most common sample preparation workflows for shotgun analysis: filter-aided sample preparation (FASP), suspension-trapping (S-Trap), and solid-phase-enhanced sample preparations (SP3). FASP showed the highest number of protein identifications for turbot samples, and S-Trap outperformed other methods for mussel samples. Subsequent functional analysis revealed a large number of Gene Ontology (GO) terms in turbot liver proteins (nearly 300 GO terms), while fewer GOs were found in mussel proteins (nearly 150 GO terms for FASP and S-Trap and 107 for SP3). This result may reflect the poor annotation of the genomic information in this specific group of animals. FASP was confirmed as the most consistent method for shotgun proteomic studies, however, the use of the other two methods might be important in specific experimental conditions (e.g., when samples have a very low amount of protein).

The main objective of this work is to present a numerical model to predict the effect of wood density in unprotected wood connections with an internal steel plate (wood–steel–wood), when comparing with the same connections using passive protection with gypsum plasterboard, submitted to fire conditions. Wood–steel–wood connections are made of four wood members, two on each side, with an internal steel plate that connects the pieces using steel dowel fasteners. First, analytical methodologies according to Eurocode 5 part 1-1 were used to design the connections at room temperature. After that, to predict the fire exposure and the connection ability, a numerical model was performed which permits to compare the fire resistance in wood–steel–wood connections without and with passive protection following the Eurocode 5 part 1-2. Results of the temperature and the wood char layer depth were compared using three different wood densities. The evolution of the charring rate was calculated in different locations of the connections and compared with the analytical value proposed by the Eurocode 5 part 1-2.

With the evolution of science and new diagnostic technologies, it was possible to observe a continuous improvement in the treatments in general and in the aid of the patients' quality of life. Malignant tumors can be primary or secondary (metastases), with abnormal growth of cells able to invade other types of tissues and organs through systemic dissemination. Sarcomas are rare primary malignancies formed from mesenchymal tissue and often located at the extremities. In this work, the main objective is to evaluate the minimization of the evolution of bone tumor lesion through the injection of bone cement, filling in the space of the lytic tumor lesion. This methodology allows to verify at the adjacent cement – bone tissue interface, an increase in temperature that can control the local growth of bone metastasis. Different computational models, obtained by medical image processing, will be carried out for two analyses (patient younger than 70 years and older than 70 years). The computational model allows a transient thermal analysis using the finite element method. The temperature results may determine the thermal necrosis effect in the bone tumor lesion. Results will be compared using three different bone cements info:eu-repo/semantics/publishedVersion

This work presents the calculation of the temperature in different cross-sections of structural profiles (IPE, HEM, L and UAP) using the lumped capacitance method and the simplified equation from Eurocode 3 part 1-2. The lumped capacitance method allows the temperature calculation of the solid body at any time instant during the heat transient process, as a constant and uniform value. The simplified equation from Eurocode 3 part 1-2 is a simple model for heat transfer based on the uniformly distributed temperature over the cross-section surface and directly proportional to section factor of the element. Steel profiles have as almost thermal behaviour uniform during the heat transfer process when submitted to fire conditions and the lumped capacitance method allows a great simplification to estimate the temperature field in the element and may be used when Biot number is lower than unity. Therefore, thermal analysis of solids with high thermal conductivity using this method is adequate. For the studied steel profiles, a thermal analysis was also performed using the simplified equation from the Eurocode 3 part 1-2 in order to validate the obtained results from the lumped capacitance method. The results from both methods are presented for discussion and analysis.

The main objective of this work is to present wood-steel-wood (W-S-W) connections in double-shear, joined by steel dowel fasteners and a steel plate as the central member. For each studied connection, different dowel diameters and external applied tensile loads in fire situation shall be taken in account. Considering the rules presented in Eurocode 5, part 1-1 and 1-2, the calculated number of dowels will be arranged in lines and columns and carry out an imposed spacing between the connectors. This work is intended to study the W-S-W connection exposed to fire using the standard curve ISO834. In the wood plates will be used a glue laminated wood, as yellow birch, with characteristics equals to GL28H. For protected connections three types of gypsum will be used in order to obtain a better insulation. Simplified equations from Eurocode 5, part 1-1 and 1-2, will be used to verify the behaviour of the connections at high temperature. A numerical procedure based on finite element method was also implemented to produce simulations focused on thermal analysis. The comparison of several results between analytical and numerical calculations showed a favourable accordance. The numerical model permits verify the effect of the steel dowels, steel plate and gypsum in the wood charring rate evolution. Even though the connection can resist for thirty minutes, is possible to observe the char layer both on protected and unprotected connection being the last the most affected. Article DOI: https://dx.doi.org/10.20319/mijst.2018.43.6078 This work is licensed under the Creative Commons Attribution-Non-commercial 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc/4.0/ or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042, USA.

The wood behavior varies with temperature, which has a negative effect, being verified by progressive properties degradation. After fire exposure, it is possible to measure the wood char layer and the remaining resistant cross-section area. Based on numerical models and analytical equations, it is possible to study the protection level of wood connections, during fire exposure, and evaluate wood and steel dowels temperature fields in conjunction. The main objective of this work is to verify the fire resistance of unprotected (W-W-W) wood connections and compare the results with protected connections using gypsum plasterboard. According Eurocode 5, part 1-2 the connections could be protected by the addition of wood paneling, wood-based panels or gypsum plasterboard type A, H or F. To obtain conclusions according the application of different type of gypsum plasterboard in the designed W-W-W connections in different densities material, numerical models were building to verify the level of protection in fire action. Design methods require the use of analytical methodologies and computational modelling to predict the fire exposure and the components capacity to resist to this action. Results of the temperature field in the studied connections under fire will be presented, with the measured char layer in unprotected members and comparing the protected efficiency with different types of gypsum plasterboard.

In bone drilling, the temperature and the level of stresses at the bone tissue are function of the drilling parameters. If certain thresholds are exceeded, irreversible damages may occur on the bone tissue. One of the main challenges in the drilling process is to control the associated parameters and even more important, to avoid the surrounding tissue damage. In this study, a dynamic numerical model is developed to determine the thermo-mechanical stresses generated during the bone drilling, using the finite element method. The numerical model incorporates the geometric and dynamic characteristics involved in the drilling processes, as well the developed temperature inside the material. The numerical analysis has been validated by experimental tests using polyurethane foam materials with similar mechanical properties to the human bone. Results suggest that a drill bit with lower drill speed and higher feed rate can reduce the strains and stresses in bone during the drilling process. The proposed numerical model reflected adequately the experimental results and could be useful in determination of optimal drilling conditions that minimise the bone injuries.

The main objective of the paper is to study the thermal effect induced by different bone cements associated with intramedullary nails, titanium and carbon, in bone metastases treatment. The thermal necrosis effect of each cement polymerisation was verified to understand the role of such procedures. Numerical models with nailing systems, introduced in a cortical and spongy bone metastasis, were developed aiming to predict the temperature produced by different types and amount of cement polymerisation. The results showed that the polymerisation heat release in all models with a cement mantle filling in around the intramedullary nail and the necrosis largest area was predicted with CMW3®. It was verified that CF/PEEK nail and high viscosity Palacos R® reduce the heat transfer and the necrosis affected area. This effect could be an advantage for treatment, which aims to keep long-term stability and local metastatic disease control for functional improvement and pain relief. info:eu-repo/semantics/publishedVersion

The mechanical behaviour of human bone tissue subject to drilling has been recently reviewed due to its increased clinical interest. However, no published data exist regarding stress analysis during the drilling. In this study, an elasto-plastic dynamic FE model of bone drilling was developed using the human cadaveric tibia obtained with a handheld 3D scanner. The FE model was validated with experimental tests and different drilling conditions were simulated in order to study the stresses distribution during the drilling process. The developed FE model was in good agreement when compared with experimental tests. Results suggest that the use of lower drill speed and higher feed-rate lead to a decrease in the stress level of the treated tibial bone. The developed FE model can be used for future studies and cover not only the mechanical behaviour of human tibiae but also the thermal aspects.

The main objective of this work is to study the thermal effect induced by the bone cement polymerisation, in the metastatic tumour minimisation and to understand the role of such procedure in bone ...

The main objective of this work is to present a methodology for safety analysis of simply supported wood beams at ambient and high temperatures with a concentrated load at mid-span. Sixteen different beam configurations will be studied. All calculations were conducted according the Eurocode 5, part 1-1 and part 1-2. During this study will be analyzed the safe load bearing capacity according standards and compared with the elastic and plastic load from beam theory. The beam theory can provide sufficient accuracy up to the point of instability. The standard methods are generally conservative and they are suitable to be used for design purposes with safety. The studied beam cross sections will be in glued laminated wood, as yellow birch, with characteristics equals to a Glulam GL28H. info:eu-repo/semantics/publishedVersion

Drilling is an operation commonly required in orthopaedic surgery for insertion of screws and internal fixation of bone fractures. Induced damage is one of the undesired effects of drilling mainly due to the use of inadequate drilling parameters. During the recent years, scientists have been trying to describe the relationship between drilling parameters and bone injury. However, no studies have examined the level of strain generated in the bone during the drilling process. This paper focuses on the analysis of different drill speeds during drilling of fresh bovine femora and human cadaveric tibiae. The main contribution of this work is to determine how differences in applied drill speeds affect the strain of cortical tissue near the drilling site and the drill bit temperature. Strains were measured in ex-vivo material during the osteotomy preparation with three drill speeds (520, 900 and 1370 r.p.m.). Additionally, a thermographic camera was used to measure the drill bit temperature. As the drilling operations are blind in nature with unknown depth, the osteotomies were performed using a drill press machine without control of the feed rate or depth. Drill bit geometry was kept constant with 4 mm of diameter, point angle 120⁰ and helix angle 30⁰. The tests were conducted at room temperature without applying cooling at the drilling zone. Bone strains near to the drilling sites were recorded with high accuracy using linear strain gages mounted around the diaphyseal cortex. It was noted that the bone strain and drill bit temperature increased with an increasing drill speed. Human and bovine bone samples presented significantly different levels of strain and temperature. Both strain and temperature were higher when drilling bovine femora than when drilling human cadaveric tibiae.

The main goal of this paper is to assess the mechanical damage in solid rigid foam materials with similar mechanical properties to the human bone induced by the cutting parameters. In the present study, a three-dimensional dynamic finite element model was developed to simulate the drilling process in solid rigid foam materials and it was validated with experimental results. Using an explicit dynamic numerical simulation, it is possible to obtain large structural deformation with high load intensity in short time frame. The developed model is used to study the effects of different high intensity loads distribution in the solid rigid foam materials. Laboratory tests were produced using biomechanical test blocks instrumented with strain gauges in different surface positions during the drilling process. The comparison between the numerical and the experimental results enables the evaluation and improvements of the cutting process. It was concluded when the feed-rate is higher, the stresses and strains in the solid rigid foam material are lower. The developed numerical model proved to be a great tool in this kind of analysis and available to use in forthcoming tests. The author of this paper acknowledges the support of the Project ‘‘Biomechanics: Contributions to the Healthcare’’ co-financed by the Regional Operational Programme of North (ON.2 - The New North), the National Strategic Reference Framework (NSRF), through the European Development Fund (ERDF) and also to the project UID/ EMS/50022/2013 of LAETA financed by FCT. info:eu-repo/semantics/publishedVersion

This work aims to determine the best combination of drilling parameters which results in the smaller temperature during the bone drilling procedure. An experimental procedure was adopted with the acquisition of two biomechanical blocks from Sawbones (composite material) with similar properties to the human bone. The goal of this experiment resulted in a drilling process to assess the generated temperature on the drill bit and simultaneously on the bone material. The Taguchi method is a powerful tool in high quality system design, and proved that can be used as optimization method to determine the best parameters combination to obtain the minimum temperatures in the drilling process.

Tabique construction is one of the most used traditional building techniques and it can be found almost everywhere in Portugal with special incidence in the northeast region. Tabique construction elements can be described as a timber structure filled on both sides with an earthbased render. Tabique elements can be found in ancient buildings, from simple construction as rural dwellings to more urban sophisticated ones. This paper presents a study of the behaviour of tabique walls, concerning its fire resistance. Therefore, an experimental analysis was performed using tabique wall panel specimens. Such wall panels were made in pine wood with an earth-based render finishing. In order to assess the thickness effect of the earth-based render on the fire resistance of the wall, three specimens with different render thicknesses of 15 mm, 10 mm and 5 mm were tested in a fire-resistance furnace according to the ISO 834 [1] standard fire curve. Fire resistance is a measure of the ability of a building element to resist a fire, usually the time for which the element can meet appropriate criteria during exposure to a standard fire resistance test. By this way it is possible to increase the safety of people and property. Two performance criteria were verified which are the integrity and the insulation. In addition, a numerical model was also developed in order to assess the tabique wall behaviour under fire conditions, which was validated using the obtained experimental results. info:eu-repo/semantics/publishedVersion

This work presents a numerical and experimental approach in order to predict the fire resistance of perforated cellular wooden slabs. The wooden slabs are lightweight, easy installation, excellent architectural, thermal and acoustic characteristics. However, its high vulnerability to fire, requires their behaviour assessed accurately. Wood material produces a surrounding char layer in depth, when exposed to fire resulting in a reduced residual section. For this purpose, different cellular wooden slabs, with the bottom surface perforated, including different small and large rectangles and circles, were tested and submitted to fire exposure. The experimental study was conducted in laboratory in accordance with European standard (EN1365-2, 2012), using a fire resistance furnace which complies the requirements of European standard (EN1363-1, 2012). Also a three-dimensional thermal and transient numerical model, using a finite element program Ansys®, was validated with experimental tests at real scale. The numerical and experimental results show good agreement. The numerical model can easily be adjusted for other constructive solutions, in order to facilitate fire safety tests, in buildings with wooden slabs used in floors or in ceilings applications. info:eu-repo/semantics/publishedVersion

The aim of the present work was to explore the feasibility of different additive manufacturing techniques applied in design, diagnosis and planning of a locked intramedullary nail used in the diaphyseal femoral fractures. Using a clinical case study of a femoral diaphysis fracture, a biomodel was developed to simulate the osseointegration bone-implant. The biomechanical analysis was performed using the finite element method and different additive manufacturing techniques were applied, particularly the full colour printing to obtain the colour levels related to von Mises stresses. The biomodel and all applied prototyping techniques have proved to be important, since they allow fast reconstruction of layered prototyping models from point cloud data with a shape errors control. In surgical procedures these models can provide practice simulators, procedure guides and models against which to measure progress by helping health professionals on an accurate and safe surgical planning. info:eu-repo/semantics/publishedVersion

Osteotomy or bone cutting is a common procedure in orthopaedic surgery, mainly in the treatment of fractures and reconstructive surgery. However, the excessive heat produced during the bone drilling process is a problem that counters the benefits of this type of surgery, because it can result in thermal osteonecrosis, bone reabsorption and damage the osseointegration of implants. The analysis of different drilling parameters and materials can allow to decrease the temperature during the bone drilling process and contribute to a greater success of this kind of surgical interventions. The main goal of this study was to build a numerical three-dimensional model to simulate the drilling process considering the type of bone, the influence of cooling and the bone density of the different composite materials with similar mechanical properties to the human bone and generally used in experimental biomechanics. The numerical methodology was coupled with an experimental methodology. The use of cooling proved to be essential to decrease the material damage during the drilling process. It was concluded that the materials with less porosity and density present less damage in drilling process. The developed numerical model proved to be a great tool in this kind of analysis. © 2016, The Brazilian Society of Mechanical Sciences and Engineering.

This work proposes an experimental and numerical method to determine char-layer and temperature in pine wood at high temperatures. The elevated temperature in the wood is due to an anaerobic heating process. A thermal unit and electro-ceramic resistance are used during experimental tests to simulate elevated temperatures in wood profi les. Wood samples have been manufactured for experimental tests. To ensure greater efficiency in the heating process, it is necessary to insulate the wood samples. A numerical method that predicts the thermal degradation of wood exposed to high temperatures is used. A non-linear thermal and transient analysis is conducted using the finite element method. Numerical results are obtained to determine temperature fi elds and char-layer in wood profi les under same con-ditions. The char-layer is calculated for pine wood profi les (Pinus pinaster) through this study. This parameter is important in safety design because it determines how cross-section size decreases to criti-cal external conditions. These methodologies could be used to assess the performance time of wood material, during exposure to high temperatures or in fi re conditions. Keywords char-layer, heating process, high temperatures, pine wood Language: en

In this study, a three-dimensional dynamic model was built to simulate the drilling process in the composite materials. With an explicit dynamic simulation it is possible to obtain large structural deformation and to apply high intensity loading in a short time frame. Using this methodology, the influence of different cutting parameters were considered during the drilling process in typical composite materials. Also, similar tests were produced in laboratory using composite blocks. Each composite material was instrumented with strain gauges to obtain the strain in different surface positions during the drilling process. The results from the numerical methodology were compared with the experimental methodology. It was concluded when the feed-rate is higher the stresses and strains in the composite material are lower. The obtained numerical and experimental results were similar. Therefore the developed numerical model proved to be a great tool in this kind of analysis.

The main goal of this study is to acquire values in spinal vertebrae, related with the cortical bone thickness, the body mass density and T–score in L2 vertebra. The study presents clinic results of sixteen women from the northwest of Portugal. For this study, a digital methodology using computed tomography and an experimental methodology with the rapid prototyping will be used for each vertebra in analysis. Discussions of results regarding the measuring of the cortical bone thickness, the body mass density, and T–score values in L2 are presented and compared with all values obtained in L3 and L4 vertebrae.

Bone drilling is a common procedure in Medicine, mainly in traumatology and orthopedic procedure for fractures fixation and in reconstructive surgery. The success of this surgical procedure is dependent on many factors, namely, on heat generation control during the bone drilling. The main concern in bone drilling is the mechanical and thermal damage of the bone induced by inappropriate parameters such as drill speed and feed-rate during the drilling. This study focuses on the temperature generated during drilling of cortical bone tissue (bovine origin) and solid rigid polyurethane foams with similar mechanical properties to the human bone tissue. Different parameters such as drill speed, feed-rate and hole depth were tested. All results showed that improvement of the drilling parameters and the drill temperatures can be estimated. It was concluded that when the drill speed and feed-rate were higher, the bone temperature increase was lower. The obtained results of temperature in the drilling process of polyurethane foam blocks or bovine bone were compared with a good agreement in between both. © 2017 World Scientific Publishing Company. This research was supported by the Portuguese Foundation of Science and Technology under research project UID/EMS/50022/2013. info:eu-repo/semantics/publishedVersion