Dissertations / Theses: 'Trusses. Strains and stresses'

1

Tentor, Lawrence B. "Position and strain feedback control for shaping an active truss." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-03242009-040345/.

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2

Smith, Megan C. "An analysis of secondary stresses in steel parallel chord Pratt trusses." Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/1399.

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3

Nagaraja, Srinidhi. "Microstructural Stresses and Strains Associated with Trabecular Bone Microdamage." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/14093.

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Bone is a composite material consisting of hydroxyapatite crystals deposited in an oriented manner on a collagen backbone. The arrangement of the mineral and organic phases provides bone tissue with the appropriate strength, stiffness, and fracture resistance properties required to protect vital internal organs and maintain the shape of the body. A remarkable feature of bone is the ability to alter its properties and geometry in response to changes in the mechanical environment. However, in cases of metabolic bone diseases or aging, bone can no longer successfully adapt to its environment, increasing its fragility. To elucidate the mechanisms of bone microdamage, this research project developed a specimen-specific approach that integrated 3D imaging, histological damage labeling, image registration, and image-based finite element analysis to correlate microdamage events with microstructural stresses and strains under compressive loading conditions. By applying this novel method to different ages of bovine and human bone, we have shown that the local mechanical environment at microdamage initiation is altered with age. We have also shown that formation of microdamage is time-dependent and may have implications in age-related microdamage progression with cyclic and/or sustained static loading. The work presented in this dissertation is significant because it improved our understanding of trabecular bone microdamage initiation and unlocked exciting future research directions that may contribute to the development of therapies for fragility diseases such as osteoporosis.

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4

Junge, Michael Dominic Alexander. "Measurement of applied stresses using the polarization of Rayleigh surface waves." Thesis, Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04062004-164653/unrestricted/junge%5Fmichael%5Fd%5Fa%5F200312%5Fms.pdf.

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Thesis (M.S. in E.S.M.)--School of Civil and Environmental Engineering, Georgia Institute of Technology, 2004. Directed by Laurence Jacobs and Jianmin Qu.
Includes bibliographical references (leaves 113-117).

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5

Carroll, Travis S. "Predicted residual strength of damaged IsoTruss® structures /." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1157.pdf.

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6

Udakara, Deepthi De Silva. "Experimental study of a modified flat dilatometer under plane strain condition." Thesis, Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22089007.

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7

Olasz, Lorant. "Residual Stresses and Strains in Cross-linked Polyethylene Power Cable Insulation." Doctoral thesis, Stockholm, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4020.

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8

Das, Yadunandan. "Characterization of stresses and strains involved in the martensitic phase transformations." Thesis, Open University, 2017. http://oro.open.ac.uk/49512/.

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Transformation-induced plasticity (TRIP) steels are an example of steels used in the automotive industry, where strain-induced martensitic transformations, associated plasticity and work hardening, enhance both the strength and ductility of the material. This has enhanced both the passenger safety (improved crash-performance) and fuel efficiency as less material is consumed (lighter structure). To gain insights into these strain-induced transformations, it is crucial to understand the impact the applied stress/strain on the martensitic transformation and how the resulting strain fields affect the further deformation and transformations. This PhD dissertation reports a series of experimental measurements on how the applied deformation affects strain-induced transformations, using three techniques, namely: electron backscatter diffraction (EBSD), high-resolution digital image correlation (HRDIC) and in situ neutron diffraction. It is shown here that applied stress favours the formation of strain-induced martensite in certain orientations of austenite. Crystallographic information gathered by EBSD and HRDIC indicates that the formation of martensite is governed by prior slip in the parent austenite. HRDIC measurements showed that strain heterogeneity is found not only between different grains within the microstructure, but even within individual austenite grains, suggesting that input parameters of macro stress strain properties are inadequate for variant selection models. EBSD, HRDIC and neutron diffraction measurements at ambient temperature confirm that the transformation is preceded by plastic deformation of the austenite crystal lattice and subsequent formation of nucleation sites. Here, it was shown that the intensity of those diffraction peaks from austenite grain families most affected by plastic deformation, decreased most due to martensitic transformation. Whereas, at the lower temperature deformation regimes, slip is suppressed, this is not the case. This dissertation illustrates how the above-mentioned techniques may be used to probe material phenomenon at various length scales, stress states and temperature regimes of interest.

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9

Kingston, Kristopher William. "Shear stresses under waves and currents." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25097.

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This study set out to investigate the shear stress behaviour at the bed under combined wave and current action. The intention of the study was to make experimental measurements to determine how wave and current shear stresses combine, so that theoretical models describing the combined flow condition could be proposed. Two types of experiment were conducted, and theoretical models for the combined flow were assessed. One set of experiments attempted to use a shear plate to make direct measurements of the combined flow shear stress, and of the shear stresses for the component waves and steady currents. This approach failed because the large correction terms introduced by the non-uniform wave pressure field could not be accurately estimated. The second set of experiments used a laser doppler anemometer to make detailed velocity profile measurements over flat sediment beds. The onset of sediment motion was used as a criterion to carefully control the experiments. It is assumed that the threshold of sediment motion represents a specific shear stress intensity at the bed for sediments of narrow size ranges. As the shear stresses can be determined from the velocity fields under waves and currents, their additive nature under combined flow conditions could be investigated. For each sediment size range, it is shown that the same maximum velocity very near the bed can be used to specify the threshold of sediment motion condition for all flow types, be they under waves, currents, or combined waves and currents. It is also shown that the near-bed velocity under a laboratory wave can be predicted accurately from second order wave theory and that the velocity under a current can be predicted from combining Manning's relation with the universal log velocity law. It is further shown that the near-bed velocity under a combined wave and current can be described by the vectorial addition of the maximum component wave velocity and the average component current velocity. The shear stress for the onset of motion is calculated for the steady current using Manning's relation, for the wave by combining the oscillatory shear stress formula with Kamphuis's rough turbulent friction factor relation, and for the combined wave and current by the simple vectorial addition of the component shear stresses, and is shown to be comparable with Shields's threshold criterion for nearly all conditions tested.
Applied Science, Faculty of
Civil Engineering, Department of
Graduate

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10

Kennedy, Kevin Francis. "A method for metal deformation and stress analysis in rolling." Connect to resource, 1986. http://rave.ohiolink.edu/etdc/view.cgi?acc%5Fnum=osu1261418472.

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11

Swett, Lauren J. "Seasonal Variations of Pavement Layer Moduli Determined Using In Situ Measurements of Pavement Stress and Strain." Fogler Library, University of Maine, 2007. http://www.library.umaine.edu/theses/pdf/SwettLJ2007.pdf.

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12

Seki, Wataru. "Analysis of strain localization in hyperelastic materials, using assumed stress hybrid elements." Diss., Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/19088.

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13

Chong, Chi Ming. "Experimental investigation and modeling of size effect in elasticity /." View Abstract or Full-Text, 2002. http://library.ust.hk/cgi/db/thesis.pl?MECH%202002%20CHONG.

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14

Wijewickreme, Dharmapriya. "Behaviour of sand under simultaneous increase in stress ratio and rotation of principal stresses." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/31410.

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Drained behaviour of sands under simultaneous increase in stress ratio and principal stress rotation is investigated. The hollow cylinder torsional (HCT) device which permits independent control of four stress parameters: mean normal stress σ'[subscript]m, stress ratio R, intermediate principal stress parameter b and the inclination α[subscript]σ of σ'₁ to the vertical, is adopted as the testing device. In order to conduct complex stress path testing in the HCT device, a new automatic stress path control system is developed. The stress non-uniformities due to the curvature of the HCT specimen is assessed using an incremental elastic representation of sand behaviour, in order to delineate the domain of stress space that could reliably be explored using the HCT device. It is shown that previous assessments of stress non-uniformities assuming linear elastic soil grossly overestimate the stress non-uniformities in a HCT sand specimen. A much larger domain of stress space with acceptable levels of non-uniformities is apparent from the results of incremental elastic analysis. New domain of stress space for reliable exploration using the HCT device is delineated and the testing program is developed so that all stress paths lie within these acceptable limits. Tests are carried out on pluviated sand under saturated drained conditions. The deformations under increasing R and α[subscript]σ is shown to be path independent, if the final stress state is within the approximate bounds of R ≤ 2 and α[subscript]σ ≤ 45°, regardless of the b or relative density D[subscript]r, levels. With increasing stress ratio R and/or principal stress rotation α[subscript]σ, the deformations gradually become path dependent. Once loaded to a stress state within the domain R ≤ 2 and α[subscript]σ ≤ 45°, the strain response under subsequent principal stress rotation is shown to be independent of the previous loading history. It is demonstrated that the strain response under any general increasing R - α path in the domain of R ≤ 2 and α[subscript]σ ≤ 45° can be predicted using the results of a limited number of tests characterizing that domain. It is shown that these concepts can be extended to loading paths which involve simultaneous increase of three stress parameters. Strain increment direction α[subscript]Δε is shown to be approximately coincident with and totally governed by the stress increment direction α[subscript]Δσ when the stress increment direction α[subscript]Δσ is more inclined towards the vertical deposition direction. When the stress increment direction is inclined closer to the bedding plane, the strain increment direction depends in addition, on other parameters such as R, α[subscript]σ and R[subscript]r etc. Under any stress path involving principal stress rotation, the deformations decrease with increasing density and therefore the principal stress rotation is more crucial in loose sands. Deformations increase with the level of stress ratio R. Level of b parameter does not affect deformations under principal stress rotation, if the rotations are small. However, with increasing α[subscript]σ deformations due to principal stress rotation tend to increase with decreasing b value.
Applied Science, Faculty of
Civil Engineering, Department of
Graduate

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15

Sævik, Svein. "On stresses and fatigue in flexible pipes." Norway : Dept. of Marine Structures, the University of Trondheim, 1992. http://catalog.hathitrust.org/api/volumes/oclc/27348152.html.

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16

Chipanga, Tendai. "Determination of the accuracy of non-destructive residual stress measurements methods." Thesis, [S.l. : s.n.], 2009. http://dk.cput.ac.za/cgi/viewcontent.cgi?article=1100&context=td_cput.

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17

Meduoye, G. O. "Investigation into the stresses and strains in toothed belt under static loading." Thesis, Cardiff University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354746.

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18

Wamelen, Arend Andries van. "Optimal design and testing of laminated specimens to evaluate competing composite failure criteria." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-08042009-040517/.

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19

Thomas, Daniel D. "High resolution optical time domain methods for measuring strain." Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-03242009-040449/.

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20

Byun, Chansup. "Free vibration and nonlinear transient analysis of imperfect laminated structures." Diss., This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-07282008-135342/.

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21

Nakhodchi, Soheil. "Prediction and Measurement of Strains and Stresses in Metallic and Non-Metallic Materials." Thesis, University of Bristol, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.525436.

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22

Boulay, Fabienne. "Suspension-flow modeling : curvilinear flows and normal stress differences." Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/11689.

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23

Vesier, Laurent S. "Fatigue crack propagation in TI-6242 as a function of temperature and waveform." Thesis, Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/18877.

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24

Venkataramanan, Chandrasekhar. "A system for data quality evaluation applied to borehole logs." Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/19438.

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25

Dong, Xiaoyuan. "Integral representations of stress intensity factors, the T-stress and the coefficients of Williams function, and a criterion for dynamic crack branching." Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/21440.

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26

Bartlett, Martin L. "The use of a laser extensometer to study the behavior of small fatigue cracks." Thesis, Georgia Institute of Technology, 1987. http://hdl.handle.net/1853/11879.

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27

Soediono, Andy H. "Near tip stress and strain fields for short elastic cracks." Diss., Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/19557.

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28

Khalili, Amin. "Stress and deformation analysis of rotating discs : a dissertation presented to the faculty of the Graduate School, Tennessee Technological University /." Click to access online version, 2006. http://proquest.umi.com/pqdweb?index=102&did=1155566681&SrchMode=1&sid=1&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1257361554&clientId=28564.

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29

Leung, Ming Yan. "Dynamic characterization of micro scale samples using the Hopkinson tensile bar technique /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?MECH%202007%20LEUNG.

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30

Diercks, David Robert Kaufman Michael Joseph. "Measurement of lattice strain and relaxation effects in strained silicon using x-ray diffraction and convergent beam electron diffraction." [Denton, Tex.] : University of North Texas, 2007. http://digital.library.unt.edu/permalink/meta-dc-3978.

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31

Hu, Ruilong. "Scale and stress effects on the behavior of ferromagnetic materials." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B38943232.

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32

Islam, Mohammad Aminul. "Constitutive modeling and plastic analysis with application to beam-to-column connections." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184486.

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Analysis and design of connections, such as beam-to-column connections, pose various complexities such as nonlinear behavior of material and geometric condition, irregularities in geometry and boundary condition. The main purpose of these types of connections is to provide adequate structural strength and a sufficiently stiff structure at working loads, and to possess sufficient ductility and strength at overloads such as may occur during a major earthquake. At present the design profession does not have established guidelines for estimating the ultimate moment and shear capacity of these connections. The assumption of linear elastic material behavior of the connections is no longer valid when the elements are stressed beyond the yield stress of the material. For such problems encountered in the design of typical structures, either the closed-form analytical solutions are extremely complex or cannot be obtained at all. Thus, numerical techniques such as finite difference, finite element and boundary integral methods are used. In this study, a finite element program is developed for plastic analysis of connections such as beam-to-column connection using a constitutive law of the material, a three parameter stress-strain relationship, which gives stress explicitly in terms of strain. One hundred and fifteen cases of beam-to-column connections subjected to moment are analysed with the finite element program developed in this study, and the results are compared with the existing approximate solution by yield line theory to propose a simple formula to correlate actual ultimate capacity to the approximate solution.

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33

JEFFREY, ROBERT GRAHAM JR. "ROCKBOLT ANALYSIS FOR REINFORCEMENT AND DESIGN IN LAYERED ROCK (COMPOSITE)." Diss., The University of Arizona, 1985. http://hdl.handle.net/10150/187982.

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The displacements and stresses in layered rock above underground openings can be calculated using a beam model for the rock layers. The traditional approach assumes that interfaces between layers are frictionless and layers can slip past one another freely as they deflect. In contrast, the design of structural laminated beams has traditionally been based on the assumption that the interfaces between layers were welded, with no slip occurring there. In this work, the theory of composite laminated beams, which allows for partial slip on layer interfaces, is applied to the problem of predicting displacements and stresses in layered roof rock. The effects of rockbolt reinforcement are modeled by discrete shear and normal stiffnesses incorporated at locations in the model where the rockbolts cross layer interfaces. Published solutions and results for laminated composite beams are reviewed. Composite laminated beam theory provided a means of accounting for rockbolt reinforcement effects and provided a conceptual framework that was used to develop two FORTRAN programs; one, based on the force method of analysis, that automatically finds shear and tensile interface failures in the system, and the other a finite element program that employs beam elements, elastic interface elements, and rockbolt elements to model a rockbolted layered rock system. Published data together with results from these programs suggest that shear reinforcement may be more effective when placed near the ends of roof layers. The normal interaction between layers tends to be uniformly distributed unless rockbolt forces act on the layers or if partial delamination of layers has occurred. Both shear and normal reinforcement will cause stresses to be redistributed within the system of layers. Analysis of this redistribution of stresses requires that the sequence of interface failure be predicted which, in turn, requires that the properties of the individual layers, of the interfaces between layers, and of the rockbolts be properly taken into account. Laminated composite beam theory and programs based on this theory provide rational and efficient ways to study and analyze the behavior of layered roof rock.

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34

Leong, Mun-Foo. "MOMENT-ROTATION CHARACTERISTICS OF BEAM-TO-COLUMN CONNECTIONS." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/275028.

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35

羅文惠 and Man-wai Law. "Strain energy capacity of reinforced concrete beams." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1987. http://hub.hku.hk/bib/B31207704.

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36

盧天健 and Tian-jian Lu. "On quasistatic cracking of materials under general loading." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1990. http://hub.hku.hk/bib/B31232346.

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37

楊貴永 and Kwai-wing Yeung. "Elastic-plastic analysis of rolling elliptical contacts and the effects of axial superimposed stresses on rolling contact fatiguefailure." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1987. http://hub.hku.hk/bib/B31231032.

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38

Hu, Ruilong, and 胡瑞龍. "Scale and stress effects on the behavior of ferromagnetic materials." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B38943232.

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39

Zhou, Guolin, and 周國林. "Complete stress-strain behavior for shear failure of rocks." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B42575679.

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40

Reed, Philip Edward 1959. "A variable moduli probabilistic constitutive model for soils." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276754.

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Measurement of stress - strain relationships in soil systems usually incorporate varying degrees of uncertainty. These uncertainties arise from laboratory testing mechanisms, sampling disturbances, errors performed by operators or technicians performing the tests, etc. Currently, deformation analyses have been modeled using several deterministic techniques. However, because of the uncertainties involved, there is a need to adapt these numerical methods into probabilistic models. This thesis develops a probabilistic constitutive model based on a variable moduli deterministic technique. First-order, second-moment stochastic methods are used to estimate a mean stress - strain curve and its ±1 standard deviation from raw data obtained on nearly identical, remolded sand samples. Probabilistic estimations for Bulk and Shear moduli are determined from the estimated mean curves and are used to develop a probabilistic constitutive model. Through the use of a probabilistic constitutive matrix, a stochastic equation is produced which can relate strains to any stress state imposed on a particular soil. This is verified through an example.

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41

Mesmar, Sultan. "On the use of viscosity as a regularisation technique for hardening/softening constitutive models." Thesis, University of Sheffield, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341798.

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42

Lu, Tian-jian. "On quasistatic cracking of materials under general loading /." [Hong Kong] : University of Hong Kong, 1990. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12973245.

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43

Law, Man-wai. "Strain energy capacity of reinforced concrete beams /." [Hong Kong : University of Hong Kong], 1987. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12228175.

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44

Yeung, Kwai-wing. "Elastic-plastic analysis of rolling elliptical contacts and the effects of axial superimposed stresses on rolling contact fatigue failure /." [Hong Kong] : University of Hong Kong, 1987. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12333669.

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45

Caceres, Arsenio. "Local damage analysis of fiber reinforced polymer matrix composites." Morgantown, W. Va. : [West Virginia University Libraries], 1998. http://etd.wvu.edu/templates/showETD.cfm?recnum=328.

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Thesis (Ph. D.)--West Virginia University, 1998.
Title from document title page. Document formatted into pages; contains x, 107 p. : ill. (some col.) Includes abstract. Includes bibliographical references (p. 104-107).

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46

Zhou, Guolin. "Complete stress-strain behavior for shear failure of rocks." Click to view the E-thesis via HKUTO, 1999. http://sunzi.lib.hku.hk/hkuto/record/B42575679.

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47

Whang, Kyunghyun. "Some problems of localized crack closure due to nearby concentrated loads /." The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487326511712949.

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48

Jitno, Hendra. "Stress-strain and strength characteristics of clay during post-cyclic monotonic loading." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/29625.

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An important consideration in the design of clay foundation for seismic or wave loading is the undrained response of clay during and after cyclic loading . Cyclic loading of clays causes, in general, a reduction in both stiffness and undrained strength on subsequent static loading. No systematic study has been carried out to assess this loss in stiffness, and there are conflicting conclusions as to the magnitude of strength reduction in studies reported in the literature. This thesis presents a study of the influence of cyclic loading on the post-cyclic undrained stress-strain characteristics of a marine clay. The influence of factors, such as, cyclic stress level, number of cycles, amplitude of maximum axial strain during cyclic loading, residual pore pressure and residual strain at the conclusion of cyclic loading is systematically investigated. In addition, the influence of initiating cyclic loading with the type of loading pulse (compression and extension) and the sense of residual strain in relation to the sense of strain during post-cyclic monotonic loading is studied. It is shown that the loss in undrained stiffness and undrained strength of the undisturbed clay as a consequence of cyclic loading are not uniquely related to the amplitude.of strain during cyclic loading, as commonly assumed. Nor can they be explained in terms of overconsolidation induced as a result of pore pressure generated due to cyclic loading. A rational explanation and correlation of both the changes in post-cyclic stress-strain and strength of clay is provided in terms of hysteretic work absorbed by the clay during cyclic loading.
Applied Science, Faculty of
Civil Engineering, Department of
Graduate

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49

Bavirisetty, Rambabu 1963. "COMPARISON OF STRESS RECOVERY ALGORITHMS." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276405.

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50

Lee, Joosik. "High resolution interferometric measurements of residual strains in composites." Diss., Virginia Tech, 1990. http://hdl.handle.net/10919/39415.

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As composites have been more widely accepted as structural materials, residual stresses in them have become a more serious issue. Various experimental methods have been developed and used to measure residual strains in different kinds and shapes of materials. The anisotropic and heterogeneous nature of composites and the complexity of residual stresses, however, pose limitations on current techniques. Those techniques lack the sensitivity or spatial resolution that is required for the measurement of local deformation of composites on a ply·by-ply basis, or give point-by-point and averaged information. Also they are incapable of resolving the complexity of combined effect of different residual stress components. I n order to measure residual strains more effectively, a new method of measuring then1 is required. Moire interferometry combined with the cut-and-sectioning method has been developed for effective measurement of residual strains in fiber-reinforced composites. This optical technique provided the capability of studying separately the effect of each component of residual stresses. It also allowed the determination of high-sensitivity full-field deformation information. This approach was applied to thick composite cylinders for measuring residual strains. The results showed a strong influence of curing procedure on residual stresses. Also, in order to determine residual strains on a within-the-ply basis, a new high-resolution data reduction procedure has been developed. This procedure enhanced the resolution of the existing data reduction technique without losing qualitative information. The combination of both aforementioned techniques provided an effective tool for measuring residual strains of composite materials. The technique is illustrated in an investigation of the effect of stacking sequence on residual strains in flat composite panels.
Ph. D.

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Dissertations / Theses on the topic 'Trusses. Strains and stresses'

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