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The main idea behind stabilisation by diaphragm action is to create a deep beam thatcan resist horizontal loads acting on a structure. It is achieved by connecting the sheetingto the primary structure of the roof so that the edge beams resist the bending momentthrough normal stresses and the sheeting resists the shear force through shear stresses.An essential assumption of a functional diaphragm system is a sufficient connectionbetween the sheeting and the primary structure.In this thesis, the global behaviour of a diaphragm, as well as possible failure modesof sheeting of different thicknesses, are investigated.A laboratory experiment is conducted in the first part of the thesis. In the experiment,two types of self-drilling screws in combination with three different plate thicknesses aretested in shear. Slip flexibility of the screws is evaluated based on the experiment andcompared to flexibilities according to European Recommendations for the Application ofMetal Sheeting Acting as a Diaphragm.In the second part of the thesis, a finite element simulation is performed on two structuresto investigate the global behaviour of the diaphragm. The experimental results are,additionally, implemented into the finite element model.In the last part, hand calculations are performed based on analytical formulas given inEuropean Recommendations for the Application of Metal Sheeting Acting as a Diaphragmand the maximum horizontal displacement of the structure is compared to the FEAresults.

Background and objective: Chronic low back pain (CLBP) is a complex musculoskeletal condition and often the source of the pain is not clear. A correlation has been found to exist between incidences of low back pain (LBP) and those with respiratory diseases such as COPD. This could give reason to believe that the sequence of events could be reversed, and LBP could elicit changes in respiratory function. The purpose of this study is to investigate if CLBP has an influence on breathing mechanics and the positioning of the diaphragm in the trunk. Methods: Volunteers were recruited between the ages of 35-65 years old with and without CLBP. All subjects underwent an MRI for imaging of their diaphragm to find the position of the diaphragm at the end of exhalation and inhalation. The height of the diaphragm at the end of exhalation and inhalation was then measured. Respiratory values were measured that included forced expiratory volume in 1 second (FEV1), and respiratory amplitude at the thoracic and abdominal level both at rest and after a series of functional exercises. Respiratory amplitude was used to measure average displacement of the abdomen and mid-ribcage during normal breathing. FEV1 was measured using a handheld spirometer and respiratory amplitude was measured using band-like respiratory sensors that were wrapped around the participants. Results: A total of 36 participants were recruited for this study (n = 21M; n = 15F), with 18 controls (n = 11M; n = 7F) and 18 with CLBP (n = 10M; 8F). Eleven variables were assessed to compare the results from the control group and CLBP group and see if there were any differences. No statistically significant differences were found for all variables assessed. Conclusion: There was no significant evidence there was a difference in diaphragm positioning and breathing mechanics in those who have CLBP. For future testing, we would want to change categorization to CLBP groups based on pain severity or compare the differences between acute LBP and CLBP. We would also consider changing our method for measuring the diaphragm such as measuring the percent change in area of the diaphragm between inhalation and exhalation. We would also consider other parameters to test that could include more use of the information given in the PROMIS questionnaire or looking at the amount of lumbar lordosis as seen on the MRI and how those values compare to among the different groups.

Problém: Obstrukce dýchacích cest a průtoková limitace, způsobená chronickou obstrukční plicní nemocí (CHOPN) nebo astma bronchiale (AB), může způsobit změny tvaru, pozice a pohybů bránice v důsledku zvýšení plicních objemů. Hypotézy: U pacientů s obstrukčním respiračním onemocněním se bude funkce bránice lišit oproti kontrolní skupině zdravých jedinců, což se projeví na jejím postavení a rozsahu pohybu. Existuje vztah mezi plicními funkcemi a polohou a pohyby bránice. Cíl: Cílem práce bylo zjistit, zda pozice, tvar a pohyby bránice u ležících pacientů s průtokovou limitací během maximálních dechových a posturálních manévrů se liší od tvaru, pozice a pohybů bránice za stejné situace u jedinců bez patologie respiračního systému. Zkoumali jsme rozdíly mezi pacienty s CHOPN, pacienty s AB a zdravými jedinci. Cílem bylo také stanovit tyto vztahy v kontextu vážnosti průtokové limitace, resp. obstrukce dechových cest. Metodika: Soubor tvořily 3 skupiny probandů, celkem 31 dospělých: 10 jedinců s klinicky stabilním AB (5 žen a 5 můžů), 11 jedinců s klinicky stabilním, středně těžkým CHOPN (7 mužu a 4 ženy) a kontrolní skupinu tvořilo 10 zdravých jedinců (5 mužů a 5 žen). Všichni probandi podstoupili komplexní měření plicních funkcí a kardiopulmonální zátežové vyšetření. Bránici jsme vyšetřovali pomocí...

The design and implementation of a micro-force displacement system was completed to test the force-displacement characteristics of square silicon diaphragms with side lengths of 4mm, 5mm, and 7mm with a thickness of 10um. The system utilizes a World Precision Instruments Fort 10g force transducer attached to a World Precession Instruments TBM4M amplifier. A Keithley 2400 source meter provided data acquisition of the force component of the system. A micro prober tip was utilized as the testing probe attached to the force transducer with a tip radius of 5um. The displacement of samples was measured using a Newport M433 linear stage driven by a Newport ESP300 motion controller (force readings at constant displacement intervals). An additional 3 linear stages were used to provide X and Y-axis positioning of samples beneath the probe tip. The system components were mounted to an optical bench to provide stability during testing. C# was used to deliver the code to the individual components of the system. In addition the software provides a graphic user interface for future users that includes a calibration utility (both X/Y and force calibration), live force-displacement graph, motion control, and a live video feed for sample alignment. Calibration of the force transducer was accomplished using an Adam Equipment PGW153e precision balance to assign force values to the voltage data produced from the transducer. Displacement calibration involved the use of a microscope calibration micrometer. The system was characterized with an equipment variability of ±1.02mg at 1.75um, and ±1.86mg at 3.5um with the ability to characterize samples with stiffness less than 279 mg/um. The displacement resolution of the system was determined to be 35 nm per step of the linear stages. The diaphragms created to test the machine were fabricated from 10um thick device layer SOI wafers. An etch consisting of 38g/l silicic acid, 7g/l ammonium persulfate, and 5% TMAH was used to reduce the formation of hillocks, and provide a consistent etch rate. A Gage R&R study was performed on the fabricated diaphragms, indicating that the deflection produced by the 4mm, 5mm, and 7mm diaphragms was resolvable by the machine. A model was developed to correlate theoretical results to the observed measured values.

This dissertation presents work targeted to study the effects of diaphragm flexibility on the seismic performance of light frame wood structures (LFWS). The finite element approach is considered for modeling LFWS as it is more detailed and provides a way to explicitly incorporate individual structural elements and corresponding material properties. It is also suitable for capturing the detailed response of LFWS components and the structure as a whole. The finite element modeling methodology developed herein is in general based on the work done by the other finite element researchers in this area. However, no submodeling or substructuring of subassemblages is performed and instead a detailed model considering almost every connection in the shear walls and diaphragms is developed. The studs, plates, sills, blockings and joists are modeled using linear isotropic three dimensional frame elements. A linear orthotropic shell element incorporating both membrane and plate behavior is used for the sheathings. The connections are modeled using oriented springs with modified Stewart hysteresis spring stiffnesses. The oriented spring pair has been found to give a more accurate representation of the sheathing to framing connections in shear walls and diaphragms when compared to non-oriented or single springs typically used by most researchers in the past. Fifty six finite element models of LFWS are created using the developed methodology and eighty eight nonlinear response history analyses are performed using the Imperial Valley and Northridge ground motions. These eighty eight analyses encompass the parametric study on the house models with varying aspect ratios, diaphragm flexibility and lateral force resisting system. Torsionally irregular house models showed the largest range of variation in peak base shear of individual shear walls, when corresponding flexible and rigid diaphragm models are compared. It is also found that presence of an interior shear wall helps in reducing peak base shears in the boundary walls of torsionally irregular models. The interior walls presence was also found to reduce the flexibility of diaphragm. A few analyses also showed that the nail connections are the major source of in-plane flexibility compared to sheathings within a diaphragm, irrespective of the aspect ratio of the diaphragm. A major part of the dissertation focuses on the development of a new high performance nonlinear dynamic finite element analysis program which is also used to analyze all the LFWS finite element models presented in this study. The program is named WoodFrameSolver and is written on a mixed language platform Microsoft Visual Studio .NET using object-oriented C++, C and FORTRAN. This tool set is capable of performing basic structural analysis chores like static and dynamic analysis of 3D structures. It has a wide collection of linear, nonlinear and hysteretic elements commonly used in LFWS analysis. The advanced analysis features include static, nonlinear dynamic and incremental dynamic analysis. A unique aspect of the program lies in its capability of capturing elastic displacement participation (sensitivity) of spring, link, frame and solid elements in static analysis. The program's performance and accuracy are similar to that of SAP 2000 which is chosen as a benchmark for validating the results. The use of fast and efficient serial and parallel solver libraries obtained from INTEL has reduced the solution time for repetitive dynamic analysis. The utilization of the standard C++ template library for iterations, storage and access has further optimized the analysis process, especially when problems with a large number of degrees of freedom are encountered. / Ph. D.

This thesis reviews the parameters required to perform linear response history analysis according to Chapter 16 of the American Standard ASCE 7-10. A careful analysis is presented about the selection of ground motions using real records and using artificial records generated such that their response spectrum matches with a defined target spectrum; three different techniques are studied for the generation of these artificial records. Also, this document revises the scaling of ground motion techniques in the American Standard ASCE-7 as well as in other seismic codes. It presents a detailed analysis of the variables influencing the scaling of ground motions, and it suggests a new scaling technique for linear response history analysis. The assumptions made establishing the flexibility of the diaphragms are also analyzed as well as dynamic methods to include accidental torsion when doing a linear response history analysis. Other modeling issues such as the orientation of the ground motion axis, scaling of element forces and displacements, orthogonal loading, solution techniques, P-Delta effects, modeling of the basement, and calculation of drifts are also studied in the context of linear response history analysis. The thesis concludes with suggested code language for linear response history analysis intended to be considered in future editions of the American Standard ASCE 7. / Master of Science

京都大学 / 新制・論文博士 / 博士(医学) / 乙第13580号 / 論医博第2302号 / 新制||医||1069(附属図書館) / (主査)教授 平井 豊博, 教授 江木 盛時, 教授 齋藤 潤 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM

Conventional fixed base walls are typically characterized by yielding that results in permanent damage, residual drifts and costly losses due to the service shutdown for structural repairs. Controlled rocking masonry walls have been developed as a solution to prevent structural damage when seismic events take place. These systems purposely allow the wall to rock from its foundation and have an uplift at the base, thus replacing the typical yielding at the base of conventional fixed-base walls. Controlled rocking masonry walls have traditionally been controlled by using unbonded post-tensioning strands to provide the self-centering behaviour. Although post-tensioning has shown favourable results, its implementation is difficult in practical applications, and post-tensioning losses due to yielding of the strands at large deformations can reduce their self-centering ability. In order to overcome such issues, an alternative controlled rocking system for masonry walls was developed recently, which is designed to self-center through vertical gravity loads only, instead of the post-tensioning tendons. The rocking response of this alternative system is controlled by using energy dissipation devices, so the system is referred to as Energy Dissipation-Controlled Rocking Masonry Walls (ED-CRMWs). The vertical gravity loads are primarily transferred to the ED-CRMWs from the floor slab at each level. Therefore, the wall-slab interaction should be investigated in order to ensure a fully resilient system. In this regard, the current study identifies and categorizes the potential issues that are expected to occur due to the interaction between the wall rocking mechanism and the floor slab, and then investigates the most common of these issues using a parametric study. The parametric study focuses on the vertical incompatibility of displacements that a hollow- core slab suffers when its supporting walls uplift by different displacements during seismic events. Three different spans, four different cross-sections and two different alternatives of prestress configurations are considered in this study. The models were developed using ABAQUS 6.18 commercial software. The results show the cracking/yielding behaviour of the slabs and their displacement capacities at five different stages. The obtained results are promising for the usage of hollow-core slabs on ED-CRMWs or similar systems that require this interaction, as the range of displacement capacities can accommodate many of the vertical displacement incompatibilities expected in many potential situations. / Thesis / Master of Applied Science (MASc)

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