| 摘要 |
<p>Constructive element of variable inertia with parabola form and a degree between 1 and 100 or greater than 100 whose transverse cross-section (through a plane perpendicular to the directrix, the latter being the line joining the centres of gravity of successive transverse cross-sections of the piece) has moment of inertia of area (with respect to the axis perpendicular to the plane of flexion passing through the centre of gravity of the cross-section; namely, the integral of differentials of the cross-section area multiplied by the distance squared of said differential of area to the said axis), variable following the directrix of the beam, minimum in the centre of the span and maximum at the ends, also being equal at both ends. Variants includes beams with more than two supports, and bracket beams (single support). This constructive element complies with a resistance function with one, two or several supports, loaded on the upper straight face thereof with any load. Another variant is that the lower face follows the form of the isostatic of compression that passes through the support points by varying the edges according to the lower face, which can also be calculated by approximation using a degree n parabola.</p> |
