Sökning: "wood bending"

Visar resultat 1 - 5 av 53 avhandlingar innehållade orden wood bending.

  1. 1. 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

  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 :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. Acetylation of Solid Wood. Wood Properties and Process Development

    Författare :Pia Larsson Brelid; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; microwave heating; deformation; wood; hardness; adhesive bonding; power penetration depth; shear strength; delamination; acetylation; pH; bending strength; dielectric properties; stability;

    Sammanfattning : The influence of acetylation on selected wood properties has been determined for Scandinavian pine and spruce wood, in order to predict the behavior of acetylated wood when it is used in different applications. Only minor differences in both bending strength and the modulus of elasticity were obtained for acetylated wood when compared with unmodified wood, and can, for practical applications, be considered unaltered. LÄS MER

  5. 4. Properties of acetylated solid wood

    Författare :Pia Larsson Brelid; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; bending strength; acetylation; shear strength; hardness; deformation; wood; adhesive bonding; delamination; stability; pH;

    Sammanfattning : .... LÄS MER

  7. 5. Thermally Modified Timber : Novel Aspects of Bending Behaviour Towards Grading and Structural Applications

    Författare :Joran van Blokland; Stergios Adamopoulos; Anders Olsson; Jan Oscarsson; Mark Hughes; Linnéuniversitetet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; checks; cracks; digital image correlation; four-point static bending; fracture characteristics; grade determining properties; non-destructive testing; Norway spruce; machine learning; outdoor above-ground exposure; timber grading; scanning electron microscopy; scanning of fibre direction; strain distribution; ThermoWood®; weathering; Forestry and Wood Technology; Skog och träteknik; Byggteknik; Civil engineering;

    Sammanfattning : Thermally modified timber (TMT) has gained market share in Europe as an environmentally friendly and durable building material. Unfortunately, TMT products are currently prohibited for use in structural applications as there is insufficient data to estimate the loss in strength due to thermal modification. LÄS MER