Sökning: "Creep"

Visar resultat 36 - 40 av 214 avhandlingar innehållade ordet Creep.

  1. 36. Volumetric Analysis in Mechanical Behaviour and Physical Ageing of Polymers

    Författare :Mats Delin; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ageing rate; Gr neisen parameter; bulk modulus; KAHR model; dilatometry; Poisson s ratio; timescale; physical ageing; dynamic mechanical properties; stress relaxation; volume changes; creep; Doolittle s equation;

    Sammanfattning : Volumetric changes associated with the deformation of ideal elastic solids depends on elastic constants of the solid and applied strain. Their magnitude is easily determined from the corresponding Poisson's ratios. LÄS MER

  3. 37. Moisture-induced stress and distortion of wood : A numerical and experimental study of wood's drying and long-term behaviour

    Författare :Sara Florisson; Sigurdur Ormarsson; Johan Vessby; Kent Persson; Linnéuniversitetet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; analytical method; calibration; controlled climate; creep; distortion; experimental methodology; FEM; fibre orientation; mechano-sorption; moisture transport; natural climate; Norway spruce; numerical model; three-dimensional; timber beam; validation; wood; Byggteknik; Civil engineering; Forestry and Wood Technology; Skog och träteknik;

    Sammanfattning : With the current advances made in three-dimensional modelling of wood, it is possible to provide an overall picture of moisture flow, and moisture-induced stress and deformations, whereas previously, experiments only provided local measurements. The main aim of the doctoral thesis is to investigate the possibilities of the developed three-dimensional numerical model to predict the behaviour of wood when simultaneously exposed to a mechanical load and a particular climate. LÄS MER

  4. 38. Analysis of the time and humidity-dependent mechanical behaviour of paper webs at offset printing preess conditions

    Författare :Jan Lif; KTH; []
    Nyckelord :creep; deformation; dynamic test; ;

    Sammanfattning : This thesis deals with the time, frequency andhumidity-dependent mechanical behaviour of paper webs at offsetprinting press conditions. How the paper web, the set-up andrunning conditions alter press performance is not fullyunderstood, and are difficult to isolate and investigateexperimentally. LÄS MER

  5. 39. Modeling of Inelastic Response of Metals with Emphasis on Cyclic Viscoplasticity

    Författare :Magnus Ekh; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; large strains; integration; anisotropy; plasticity; creep; viscoplasticity; kinematic hardening; metals; damage; calibration;

    Sammanfattning : This thesis is concerned with the continuum modeling of the macroscopic behavior of engineering metals, in particular as part of life prediction strategies. Focus is primarily placed on the formulation and numerics of models for cyclic rate-dependent response. LÄS MER

  7. 40. Assessment of Long-Term Losses in Prestressed Concrete Structures - Application for Nuclear Reactor Containments

    Författare :Peter Lundqvist; Avdelningen för Konstruktionsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; KstrConcrete; Nuclear reactor containments; prestressed concrete; prestress losses; bonded tendons; creep; shrinkage; relaxation; prediction models; resonance frequency; acoustoelasticity.;

    Sammanfattning : Most nuclear reactors, both in Sweden and worldwide, are enclosed by a prestressed concrete containment. The main purpose of the containment is to prevent any radioactive discharge to the environment in the event of a major internal accident. LÄS MER