Sökning: "Creep"

Visar resultat 1 - 5 av 156 avhandlingar innehållade ordet Creep.

  1. 1. Mechanical Properties of Welds at Creep Activation Temperatures

    Detta är en avhandling från Stockholm : KTH

    Författare :Henrik C.M. Andersson-Östling; KTH.; KTH.; [2010]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; creep; creep crack propagation; OFHC copper; welds; nuclear waste disposal; creep modeling; TECHNOLOGY Materials science; TEKNIKVETENSKAP Teknisk materialvetenskap;

    Sammanfattning : Welds in materials intended for service at temperatures above the creep activation temperature often develop damage before the base metal. The weld is a discontinuity in the material and stresses and strains often accumulate in the weld. Knowledge of the properties of the weld is essential to the safe operation of the component containing the weld. LÄS MER

  2. 2. Numerical simulation of weldment creep response

    Detta är en avhandling från Stockholm : Materialvetenskap

    Författare :Peter Segle; KTH.; [2002]
    Nyckelord :ABAQUS; constraint effect; continuum damage mechanics; creep; creep crack growth; design; design code;

    Sammanfattning : In-service inspections of high temperature pressureequipment show that weldments are prone to creep and fatiguedamage. It is not uncommon that severely damaged weldments arefound even before the design life of the component has beenreached. LÄS MER

  3. 3. Time-dependent crack growth and fracture in concrete

    Detta är en avhandling från Division of Building Materials, LTH, Lund University

    Författare :Fan Ping Zhou; [1992]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; creep; rupture test; sustained loading; deformationer; betong; brottmekanik; sprickor; sprickbildning; sprickmodeller; krypning; spänningar; brottenergi; brottspänningar; beräkningsmodeller; finita element; teori; laboratorieförsök; creep rupture; tidsberoende; fracture mechanics; Fictitius Crack Model; finite element method; visco-elastic fracture; time-dependent fracture; creep crack growth; concrete; tensile fracture; crack model;

    Sammanfattning : The objectives of this thesis are to study time-dependent fracture behaviour in concrete. The thesis consists of an experimental study, constitutive modelling and numerical analysis... LÄS MER

  4. 4. Concrete creep and thermal stresses new creep models and their effects on stress development

    Detta är en avhandling från Luleå : Luleå tekniska universitet

    Författare :Gustaf Westman; [1999]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Structural Engineering; Konstruktionsteknik;

    Sammanfattning : This thesis deals with the problem of creep in concrete and its influence on thermal stress development. New test frames were developed for creep of high performance concrete and for measurements of thermal stress development. Tests were performed on both normal strength and high performance concretes. LÄS MER

  5. 5. Aspects of creep-fatigue in gas turbine hot parts

    Detta är en avhandling från Linköping : Linköpings universitet

    Författare :Magnus Hasselqvist; Linköpings universitet.; Linköpings universitet.; [2001]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; creep; fatigue; TMF; gas turbine; modelling; life assessment; ageing; micro-structure; solute drag; back stress; Haynes 230; IN792;

    Sammanfattning : The goal is reliable creep-fatigue lifing methodology for industrial gas turbines.A literature study on high temperature materials used in gas turbines reveals that:• Most testing/modelling work has focused on characterisation and modelling of material response in isothermal standard tests, i.e. creep, tensile and LCF tests. LÄS MER