Sökning: "bending strength"

Visar resultat 1 - 5 av 135 avhandlingar innehållade orden bending strength.

  1. 1. Fracture mechanics studies of non-yielding materials like concrete : modelling of tensile fracture and applied strength analyses

    Författare :Per-Johan Gustafsson; Institutioner vid LTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; cracking; corners; test-specimens; strength; tension; fracture mechanics; strain localization; size-effect; flexural strength; LEFM; fictitious crack model; Weibull; FEM; pipes; shear strength; concrete; diagonal tension;

    Sammanfattning : Fracture mechanics studies of non-yielding materials are presented. The studies are based on theoretical models for the macroscopical mechanical behaviour of materials during tensile stress induced fracture. A number of applied numercal analysis are indicated. LÄS MER

  3. 2. Strength grading of structural timber and EWP laminations of Norway spruce : Development potentials

    Författare :Jan Oscarsson; Anders Olsson; Marie Johansson; Mikael Perstorper; SP Sveriges Tekniska Forskningsinstitut; []
    Nyckelord :AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; bending strength; fibre angle; grain angle; knots; laser scanning; machine strength grading; modulus of elasticity; strain measurement; structural timber; tensile strength; wood; böjhållfasthet; draghållfasthet; elasticitetsmodul; fibervinkel; konstruktionsvirke; kvistar; laserskanning; maskinell hållfasthetssortering; trä; töjningsmätning; Byggteknik; Civil engineering;

    Sammanfattning : Strength grading of structural timber is a process by which value is added to sawn products. It is to the greater part carried out using machine grading based on statistical relationships between so called indicating properties and bending strength. LÄS MER

  4. 3. Local variation in bending stiffness in structural timber of Norway spruce : for the purpose of strength grading

    Författare :Min Hu; Marie Johansson; Linnéuniversitetet; []
    Nyckelord :AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; LANTBRUKSVETENSKAPER; ENGINEERING AND TECHNOLOGY; AGRICULTURAL SCIENCES; digital image correlation; fibre angle; high resolution; laser scanning; local stiffness; MOE profile; mode shape curvature; strain field; strength grading; structural timber; tracheid effect; Digital image correlation; fibervinkel; laserskanning; lokal styvhet; MOE-profil; töjningsfält; hållfasthetssortering; konstruktionsvirke; trakeideffekt; Forestry and Wood Technology; Skog och träteknik;

    Sammanfattning : Most strength grading machines on the European market use an averagemodulus of elasticity (MOE), estimated on a relatively large distance along awood member, as the indicating property (IP) to bending strength. Theaccuracy of such grading machines in terms of coefficient of determination israther low at R2 ≈ 0.5. LÄS MER

  5. 4. Modelling the Variability of Bending Strength in Structural Timber - Length and Load Configuration Effects

    Författare :Tord Isaksson; Avdelningen för Konstruktionsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; code; reliability-based design; Weibull; test standard; load configuration effect; length effect; weak section; machine grading; visual grading; variability; Structural timber; bending strength; simulation; monte carlo simulation.; Building construction; Byggnadsteknik;

    Sammanfattning : The load carrying capacity of a beam of structural timber is dependent both on the span of the beam and the type of loading. The longer the beam and the more uniform the moment distribution, the lower the load carrying capacity. This phenomenon is due to the variability of material properties within a piece of timber. LÄS MER

  7. 5. Bonding veneers using only heat and pressure : focus on bending and shear strength

    Författare :Carmen Cristescu; Luleå tekniska universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; self-bonding; auto-adhesion; LVL; beech; Fagus Sylvatica; high-temperature; pressure; Wood Technology; Träteknik;

    Sammanfattning : A compact laminated board can be obtained by pressing layers of veneers with no other material or substance placed between them. The process does not require the use of steam pretreatment, surface activation methods, a gastight press, friction or adhesives. It strictly involves the heat and the pressure induced by the press in the veneers. LÄS MER