| 摘要 |
<p>The essence of the invention is the so-called procedure for increasing the bending strength by pre-bending which enables the activation of the not yet exploited bending strength of those points in the material which are in the vicinity of the neutral plane. In structural elements subjected prevailingly to bending loads these points are usually the least loaded. The procedure of increasing the bending strength by pre-bending enables that, by pre-bending of one or several component elements of the cross section , a highest, favourable counter-distribution of imposed stresses with respect to the foreseen loading is created along the cross section. Pre-bending enables that under full load, a most constant stress distribution is achieved in the compressive as well as tensile region. Very similar results are obtained by the already known technology of pre-stressing the reinforced concrete structures in civil engineering. The procedure is useful for the manufacture of the elements of line structures as well as plane and space structures. It is especially applicable in cases when due to poor flank load carrying capacity of the material, clamping in the pre-stressing system is made difficult. One such example is the use of pre-bending in the manufacture of glued wooden beams.</p> |
