Расчет и усиление предельно-напряженных приопорных зон высоких деревоклееных балочных конструкций

2015 
We consider the engineering calculation of maximum stressed abutment sections of high glue-wood beam constructions, as well as strengthening these areas with glass nanoassembly. In supports of glued wood beams complex stress arises causing spalling along the fibers, crushing reproach fibers and stretching at an angle to the fibers. The article proposes a new way of strengthening these areas during the production of beams, the essence of which consists in the fact that the ends of the beam constructions are put in clip of glass in one or several layers glued to wood by epoxy resin composition including carbon nanotubes. In the calculations, wood is considered as transport materials described by rheological equations as viscosity elastic elastic body. Physical and mathematical models of fiberglass are selected. Strength of materials formulas calculated geometrical characteristics of the reduced section of strengthened near mounting area of high glued wood beams. Engineering method has shown that the existing method of calculation of wooden bent elements (on the maximum principal stresses in the middle of the span and the maximum shear stress on the support) is not applicable to high glue-wood beams. Tensile stresses at an angle to the fibers in the support areas reach peak values at a load of approximately twice lower than the load at which the maximum shear stress takes place. Engineering calculations found that supports of high beam constructions need to be strengthened. Minimal effect on enhancing by clip of glass nanoassembly by cleaving along the fibers ≥ 8 %, when crumpled across the fibers ≥ 7 %, in tension at an angle to the fibers ≥ 9 %. It was proposed to simplify the formula of geometrical characteristics of the reduced section in order to facilitate further calculations.
    • Correction
    • Source
    • Cite
    • Save
    • Machine Reading By IdeaReader
    0
    References
    0
    Citations
    NaN
    KQI
    []