| 摘要 |
The triangulation of a trellis beam for a jib (13) comprises, for a beam lateral face defined by a upper (2) and lower (3) ribs, compression bars (14) each connecting the upper to the lower rib. Oblique traction bars (17) each connect the top (15) of a compression bar to the lower rib in a point (18) located at a pitch (P) in front of the base of the compression bar. Other oblique traction bars (19) each connect the top of a compression bar to the lower rib in a point (20) located at two pitches in front of the base (16) of this bar. |
