Gait is the method of human locomotion using limbs. Recently, the analysis of human motion, specifically human gait, has received a large amount of research attention. Human gait can contain a wide variety of information that can be used in biometrics, disease diagnosis, injury rehabilitation, and load determination. In this dissertation, the development of a model-based gait analysis technique to classify external loads is presented. Specifically, the effects of external loads on gait are quantified and these effects are then used to classify whether an individual gait pattern is the result of carrying an external load or not. First of all, the reliability of using continuous relative phase as a metric to determine loading condition is quantified by intra-class correlation coefficients (ICC) and the number of required trials is computed. The ICC(2, 1) values showed moderate reliability and 3 trials are sufficient to determine lower body kinematics under two external load conditions. Then, the work was conducted to provide the baseline separability of load carriage conditions into loaded and unloaded categories using several lower body kinematic parameters. Satisfactory classification of subjects into the correct loading condition was achieved by resorting to linear discriminant analysis (LDA). The baseline performance from 4 subjects who were not included in training data sets shows that the use of LDA provides an 88.9% correct classification over two loaded and unloaded walking conditions. Extra weights, however, can be in the form of an external load carried by an individual or excessive body weight carried by an overweight individual. The study now attempts to define the differences in lower body gait patterns caused by either external load carriage, excessive body weight, or a combination of both. It was found significant gait differences due to external load carriage and excessive body weight. Principal Component Analysis (PCA) was also used to analyze the lower body gait patterns for four loading conditions: normal weight unloaded, normal weight loaded, overweight unloaded and overweight loaded. PCA has been shown to be a powerful tool for analyzing complex gait data. In this analysis, it is shown that in order to quantify the effects of external loads for both normal weight and overweight subjects, only two principal components (PCs) are needed. The results in this dissertation suggest that there are gait pattern changes due to external loads, and LDA could be applied successfully to classify the gait patterns with an unknown load condition. Both load carriage and excessive body weight affect lower body kinematics, but it is proved that they are not the same loading conditions. Methods in the current work also give a potential for new medical and clinical ways of investigating gait effects in osteoarthritis patients and/or obese people. / Ph. D.

A percepção sobre as cargas externas permite a criação de estratégias eficientes para o controle do estresse mecânico aplicado ao aparelho locomotor. As poucas referências disponíveis na literatura especializada estudaram a questão, a partir da associação das respostas dinâmicas (força de reação do solo e pressão plantar) e subjetivas na locomoção. Entretanto, não há trabalhos que associem o comportamento da percepção de carga ao das respostas eletromiográficas e não há na literatura o estudo das relações entre as respostas subjetivas, dinâmicas e eletromiográficas na locomoção (corrida e marcha) entre os grupos com e sem comprometimento das sensações somatosensoriais na região plantar. O presente estudo objetivou verificar as correlações entre os valores dinâmicos, eletromiográficos e subjetivos: a) Na corrida de atletas (corredores e jogadores de handebol) em função do uso da palmilha (calçado com palmilha x calçado sem palmilha) e b) Na marcha de diabéticos neuropatas, de idosos saudáveis e de adultos. Para tanto, os registros dinâmicos (FRS), eletromiográficos e subjetivos (escala Ratings of Perceived Exertion de Borg) foram mensurados. Os voluntários se locomoveram na esteira por um período de 50 minutos em velocidade constante e a cada 10 minutos as variáveis dinâmicas (sistema GAITWAY - duas plataformas de força piezoelétricas dispostas em série, montadas na superfície de uma esteira rolante), eletromiográficas (EMG 1000 com eletrodos de superfície ativos, préamplificados, conectados aos canais ativos do equipamento) dos músculos tibial anterior (TA), gastrocnêmio lateral (GL), reto femoral (RF), vasto lateral (VL) e bíceps femoral cabeça longa (BF) e subjetivas foram adquiridas. Os grupos de corredores (C) e atletas de handebol (AH) efetuaram a corrida e o uso da palmilha do calçado foi manipulado; enquanto, o grupo de diabéticos neuropatas (DN), idosos (I) e adultos (A) caminharam. Para todos os grupos estudados, não foram verificadas variações na intensidade das cargas aplicadas ao aparelho locomotor nos seis instantes de coleta e as respostas subjetivas apresentaram valores crescentes e significativos (p<0,05) entre a maioria dos instantes de coleta. Somente para I, os resultados de correlação obtidos entre as variáveis dinâmicas (GC: r=0,73; Imp50: r=0,64; Fy1: r=0,50) e a percepção de carga na marcha foram fortes e significativos (p<0,01). Sabendo que, os I eram sedentários, possivelmente as maiores correlações de respostas subjetivas com objetivas deste grupo podem estar pautadas na percepção de cargas mais intensas do que as experimentadas no cotidiano. Esta situação corrobora com os resultados de estudos relacionados ao tema, que sugerem que as respostas subjetivas são baseadas nas informações mecânicas de movimentos que geram cargas de intensidades distintas em relação a que o sujeito está mais exposto no cotidiano. As variáveis eletromiográficas sofreram variações discretas entre os períodos de coleta para todos os grupos analisados, decorrentes de artefatos no sistema de aquisição de dados; e os valores atribuídos por todos voluntários para as variáveis subjetivas indicaram comportamento crescente e significativo (p<0,05). Ainda assim, as correlações obtidas entre as variáveis eletromiográficas e subjetivas para todos os grupos foram fracas. Concluise que, valores eletromiográficos e dinâmicos não se relacionam de forma consistente com a percepção de cargas mecânicas, demonstrando que a resposta subjetiva não pode ser utilizada como parâmetro de controle de estresse mecânico em movimentos cuja intensidade de cargas não varia / The perception of external loads allows the use of efficient strategies to control the mechanical stress applied to the locomotor structures. The few available references in the specialized literature studied this subject starting from the association of dynamic (ground reaction force and plantar pressure) and subjective responses during locomotion. However, there isnt any study associating load perception behavior to electromyographic responses and, also, there isnt any study in the literature about the relationship among subjective, dynamic and electromyographic responses during locomotion (running and walking) in groups with and without somatosensory compromisings in the plantar area of the foot. Therefore, the aim of this study was to verify the correlation among dynamic, electromyographic and subjective data: a) During athletes running (runners and handball players), manipulating the use of inner soles (shoe with inner sole x shoe without inner sole); and b) During the walking of diabetic neuropathic people, healthy elderly people and adults. To meet this purpose, dynamic (GRF), electromyographic and subjective (Borgs Ratings of Perceived Exertion) data were measured. The volunteers walked or ran in a treadmill for 50 minutes in a constant speed, and every 10 minutes were acquired the dynamic data (GAITWAY System - two piezoelectric force plates placed on the treadmill surface), electromyographic data (EMG 1000 System active and pre-amplified surface electrodes, connected to the active channels of the equipment) of the muscles Tibialis Anterior (TA), Gastrocnemius Lateralis (GL), Rectus Femoris (RF), Vastus Lateralis (VL) and Biceps Femoris - long head (BF), and subjective data. The groups of runners (C) and handball athletes (AH) performed the running condition and had the use of the inner sole of the shoe manipulated; while, the groups of diabetic neuropathic people (DN), elderly (I) and adults (A) walked. For all of the studied groups, was not verified variations in the intensity of the loads applied to the human body in the six acquisition instants, while the subjective responses presented growing and significant values (p <0,05) among most of the acquisition instants. The correlation between the dynamic variables (GC: r=0,73; Imp50: r=0,64; Fy1: r=0,50) and the load perception during walking was strong and significant (p <0,01) only for I. Knowing that the I was sedentary, its possible that the great subjective and objective response correlations about this group may be based in the perception of intense charges than the experienced in the common day. This situation mach with the results of the articles related with the objective of the work and suggest that subjective responses are based on the mechanical information generate of loads of different intensities. The electromyographic variables suffered small variations among the periods of data acquisition for all of the analyzed groups, probably because of movement variability and the values attributed by all volunteers for the subjective variables indicated growing and significant behavior (p <0,05). Nevertheless, the correlations obtained between the electromyographic and subjective variables for all groups were weak. It is possible to conclude that the values of dynamic and electromyographic dont have relation in a consistent way with the perception of mechanical charges, showing that the subjective response cant be used as parameter of control of the mechanical stress in movements were the intensity of the charges didnt change

A percepção sobre as cargas externas permite a criação de estratégias eficientes para o controle do estresse mecânico aplicado ao aparelho locomotor. As poucas referências disponíveis na literatura especializada estudaram a questão, a partir da associação das respostas dinâmicas (força de reação do solo e pressão plantar) e subjetivas na locomoção. Entretanto, não há trabalhos que associem o comportamento da percepção de carga ao das respostas eletromiográficas e não há na literatura o estudo das relações entre as respostas subjetivas, dinâmicas e eletromiográficas na locomoção (corrida e marcha) entre os grupos com e sem comprometimento das sensações somatosensoriais na região plantar. O presente estudo objetivou verificar as correlações entre os valores dinâmicos, eletromiográficos e subjetivos: a) Na corrida de atletas (corredores e jogadores de handebol) em função do uso da palmilha (calçado com palmilha x calçado sem palmilha) e b) Na marcha de diabéticos neuropatas, de idosos saudáveis e de adultos. Para tanto, os registros dinâmicos (FRS), eletromiográficos e subjetivos (escala Ratings of Perceived Exertion de Borg) foram mensurados. Os voluntários se locomoveram na esteira por um período de 50 minutos em velocidade constante e a cada 10 minutos as variáveis dinâmicas (sistema GAITWAY - duas plataformas de força piezoelétricas dispostas em série, montadas na superfície de uma esteira rolante), eletromiográficas (EMG 1000 com eletrodos de superfície ativos, préamplificados, conectados aos canais ativos do equipamento) dos músculos tibial anterior (TA), gastrocnêmio lateral (GL), reto femoral (RF), vasto lateral (VL) e bíceps femoral cabeça longa (BF) e subjetivas foram adquiridas. Os grupos de corredores (C) e atletas de handebol (AH) efetuaram a corrida e o uso da palmilha do calçado foi manipulado; enquanto, o grupo de diabéticos neuropatas (DN), idosos (I) e adultos (A) caminharam. Para todos os grupos estudados, não foram verificadas variações na intensidade das cargas aplicadas ao aparelho locomotor nos seis instantes de coleta e as respostas subjetivas apresentaram valores crescentes e significativos (p<0,05) entre a maioria dos instantes de coleta. Somente para I, os resultados de correlação obtidos entre as variáveis dinâmicas (GC: r=0,73; Imp50: r=0,64; Fy1: r=0,50) e a percepção de carga na marcha foram fortes e significativos (p<0,01). Sabendo que, os I eram sedentários, possivelmente as maiores correlações de respostas subjetivas com objetivas deste grupo podem estar pautadas na percepção de cargas mais intensas do que as experimentadas no cotidiano. Esta situação corrobora com os resultados de estudos relacionados ao tema, que sugerem que as respostas subjetivas são baseadas nas informações mecânicas de movimentos que geram cargas de intensidades distintas em relação a que o sujeito está mais exposto no cotidiano. As variáveis eletromiográficas sofreram variações discretas entre os períodos de coleta para todos os grupos analisados, decorrentes de artefatos no sistema de aquisição de dados; e os valores atribuídos por todos voluntários para as variáveis subjetivas indicaram comportamento crescente e significativo (p<0,05). Ainda assim, as correlações obtidas entre as variáveis eletromiográficas e subjetivas para todos os grupos foram fracas. Concluise que, valores eletromiográficos e dinâmicos não se relacionam de forma consistente com a percepção de cargas mecânicas, demonstrando que a resposta subjetiva não pode ser utilizada como parâmetro de controle de estresse mecânico em movimentos cuja intensidade de cargas não varia / The perception of external loads allows the use of efficient strategies to control the mechanical stress applied to the locomotor structures. The few available references in the specialized literature studied this subject starting from the association of dynamic (ground reaction force and plantar pressure) and subjective responses during locomotion. However, there isnt any study associating load perception behavior to electromyographic responses and, also, there isnt any study in the literature about the relationship among subjective, dynamic and electromyographic responses during locomotion (running and walking) in groups with and without somatosensory compromisings in the plantar area of the foot. Therefore, the aim of this study was to verify the correlation among dynamic, electromyographic and subjective data: a) During athletes running (runners and handball players), manipulating the use of inner soles (shoe with inner sole x shoe without inner sole); and b) During the walking of diabetic neuropathic people, healthy elderly people and adults. To meet this purpose, dynamic (GRF), electromyographic and subjective (Borgs Ratings of Perceived Exertion) data were measured. The volunteers walked or ran in a treadmill for 50 minutes in a constant speed, and every 10 minutes were acquired the dynamic data (GAITWAY System - two piezoelectric force plates placed on the treadmill surface), electromyographic data (EMG 1000 System active and pre-amplified surface electrodes, connected to the active channels of the equipment) of the muscles Tibialis Anterior (TA), Gastrocnemius Lateralis (GL), Rectus Femoris (RF), Vastus Lateralis (VL) and Biceps Femoris - long head (BF), and subjective data. The groups of runners (C) and handball athletes (AH) performed the running condition and had the use of the inner sole of the shoe manipulated; while, the groups of diabetic neuropathic people (DN), elderly (I) and adults (A) walked. For all of the studied groups, was not verified variations in the intensity of the loads applied to the human body in the six acquisition instants, while the subjective responses presented growing and significant values (p <0,05) among most of the acquisition instants. The correlation between the dynamic variables (GC: r=0,73; Imp50: r=0,64; Fy1: r=0,50) and the load perception during walking was strong and significant (p <0,01) only for I. Knowing that the I was sedentary, its possible that the great subjective and objective response correlations about this group may be based in the perception of intense charges than the experienced in the common day. This situation mach with the results of the articles related with the objective of the work and suggest that subjective responses are based on the mechanical information generate of loads of different intensities. The electromyographic variables suffered small variations among the periods of data acquisition for all of the analyzed groups, probably because of movement variability and the values attributed by all volunteers for the subjective variables indicated growing and significant behavior (p <0,05). Nevertheless, the correlations obtained between the electromyographic and subjective variables for all groups were weak. It is possible to conclude that the values of dynamic and electromyographic dont have relation in a consistent way with the perception of mechanical charges, showing that the subjective response cant be used as parameter of control of the mechanical stress in movements were the intensity of the charges didnt change

El presente trabajo de tesis busca evaluar las respuestas estructurales de 3 tipos de torres de acero en el proyecto “Línea de Transmisión 220 kV Machupicchu - Quencoro - Onocora - Tintaya. Estas estructuras a evaluar se determinaron de acuerdo a su incidencia en el proyecto. En este proyecto de investigación, nuestros intereses son evaluar las respuestas estructurales en el diseño de las estructuras de soporte para la línea de transmisión, centrando nuestro desarrollo en las solicitaciones reales debido a la distribución y replanteo topográfico de las estructuras en campo. Luego de ello continuaremos con la evaluación de las reacciones a nivel de fundación a fin de poder evaluar las reacciones de tracción y compresión con lo cual se procederá a diseñar las nuevas fundaciones de concreto. / This thesis seeks to evaluate the structural responses of 3 types of steel towers in the project "Transmission Line 220 kV Machupicchu - Quencoro - Onocora - Tintaya. These structures to be evaluated were determined according to their impact on the project. In this research project, our interests are to evaluate the structural responses in the design of the support structures for the transmission line, focusing our development on the real benefits due to the distribution and topographical reframing of the structures in the field. After that, we will continue with the evaluation of the reactions at the foundation level in order to evaluate the traction and compression reactions, which will proceed to design the new concrete foundations. / Tesis

Reinforced concrete deep beams are known for applications in tall buildings, foundations and offshore structures. Deep beams are structural elements with length and height within the same magnitude and have significantly smaller thickness compared to a conventional concrete beam. Deep beams in bending have non-linear strain distribution compared to conventional beams where Bernoulli’s hypothesis is valid. Crack formation is a common problem in reinforced concrete structures, which reduce the durability of the structure. Once the concrete cracks the tension reinforcement carry the tensile forces instead of the concrete. Therefore, the design of tension reinforcement is important since the serviceability should be retained even after the structure cracks. The crack widths can be limited by using proper reinforcement and one alternative is to combine tensile reinforcement with crack reinforcement.  The function of the reinforcement is to distribute the cracks over the cross section which leads to that many smaller cracks occur instead of fewer, wider cracks. Small cracks are seen as less of a problem compared to large cracks since larger cracks reduce the durability significantly. For deep beams, there is at the present no well-substantiated analysis model for how crack widths shall be calculated when having reinforcement in multiple layers with different diameters. The use of crack reinforcement in the outer bottom layer has by tradition been considered as a cost efficient way to achieve small crack widths. In this work the crack width in deep beams have been analysed using the finite element program Atena 2D. The numerical results have been verified by analytical calculations based on Eurocode 2. The aim is to achieve reduced crack widths  by analysing the combination of crack- and tensile reinforcement compared to the case with tensile reinforcement only. Tensile reinforcement has a larger diameter, for example ø25 mm, and crack reinforcement has smaller diameters, often between ø10 and ø16 mm. The result from the calculations with Atena showed that there was an improvement regarding the reduction of crack widths when using crack reinforcement in combination with tensile reinforcement compared to using tensile reinforcement only. However, this improvement decreased by using reinforcement in multiple layers since a tensile reinforcement bar 1ø25 mm needed to be replaced by approximately six crack reinforcement bars 6ø10 mm in order to achieve the same total reinforcement area. The main disadvantage was that more space was required to place all reinforcement bars in the cross section, which reduced the lever arm. The reduction of the lever arm resulted in a reduced capacity for the reinforcement and the cracks might unintentionally become wider than expected. Furthermore, significant reduction of both crack widths and reinforcement stresses were obtained when the total area for a case with 7ø25 mm was increased to 9ø25 mm. The increased total area of only tensile reinforcement ø25 mm reduced the crack width more compared to using a combination of crack- and tensile reinforcement, which could simplify the construction work at building sites and minimize time consumption. / Armerade höga betongbalkar är kända för tillämpningar i höga byggnader, grundsulor och offshore konstruktioner. Höga balkar är konstruktionselement med längd och höjd i samma storleksordning och har betydligt mindre tjocklek jämfört med en konventionell betongbalk. Höga balkar i böjning har en icke-linjär töjningsfördelning jämfört med konventionella balkar där Bernoullis hypotes gäller. Sprickbildning är ett vanligt problem i armerade betongkonstruktioner, vilket minskar beständigheten hos konstruktionen. När betongbalken spricker kommer armeringen att ta upp dragkraften istället för betongen därför är utformningen av böjarmering viktig eftersom bruksgränstillståndet bör behållas även efter att konstruktionen spricker. Sprickvidderna kan begränsas genom att använda korrekt armering och ett alternativ är att kombinera kraftarmering med sprickarmering. Armeringens funktion är att sprida ut sprickorna över tvärsnittet vilket leder till att många små sprickor uppkommer i stället för färre, bredare sprickor. Små sprickor ses som ett mindre problem jämfört med stora sprickor eftersom större sprickor minskar beständigheten avsevärt. För höga balkar finns det för närvarande ingen välunderbyggd analysmodell för hur sprickvidder ska beräknas när de har armering i flera lager och med olika diametrar. Användningen av sprickarmering har traditionellt ansetts vara ett kostnadseffektivt sätt att uppnå små sprickvidder. I detta arbete har sprickvidden i höga balkar analyserats med hjälp av finita elementprogrammet Atena 2D. De numeriska resultaten har verifierats med analytiska beräkningar baserade på Eurokod 2. Syftet är att uppnå reducerade sprickvidder genom att analysera kombinationen av sprick- och kraftarmering jämfört med fallet med endast kraftarmering. Kraftarmeringen har en större diameter, till exempel ø25 mm och sprickarmering har mindre diametrar, ofta mellan ø10 och ø16 mm. Resultaten från beräkningarna i Atena visade att sprickvidderna minskade vid användning av sprickarmering i kombination med kraftarmering jämfört med användning av endast kraftarmering. Denna förbättring minskade emellertid i och med användning av armering i flera lager. En kraftarmeringsstång 1ø25 mm behöver ersättas med ungefär sex sprickarmeringsstänger, 6ø10 mm, för att uppnå samma totala armeringsarea. Den största nackdelen var att det krävdes mer utrymme för att placera alla sprickarmeringsstänger i tvärsnittet, vilket minskade hävarmen. Minskningen av hävarmen medförde en reducerad kapacitet i armeringen och sprickorna blev bredare än förväntat. Vidare erhölls signifikant reduktion av både sprickvidder och armeringsspänningar när den totala arean för ett fall med 7ø25 mm ökades till 9ø25 mm. Den ökade totalarean av endast kraftarmeringsstänger ø25 mm minskade sprickvidden mer jämfört med att använda en kombination av sprick- och kraftarmering vilket skulle kunna förenkla byggarbetet på byggarbetsplatser och minimera tidsförbrukningen.