ring forces and the bending moments in the irrigation tanks the cylinder theory

International Nuclear Information System (INIS) Torsion of the central pair microtubules in eukaryotic flagella due to bending-driven lateral buckling Additionally, mathematical models were derived to calculate the dynamic maximum lateral displacements and positions of the individual walking on the wood Ijoists for the same five different supported end Mathematical models were derived to calculate the static critical loads for the simply supported end condition and four wood I-joist hanger supported end conditions.

The dynamic lateral-torsional buckling instability was analyzed by linearly combining the static lateral-torsional buckling instability with the lateral bending motion of the wood Ijoists. The goal of this research was to derive mathematical models to predict the dynamic lateral-torsional buckling instability of wood composite I-joists loaded by individuals walking considering different supported end conditions and bracing system configurations.

Furthermore, no research was found considering the effects of the supported end conditions and partial bracing in the lateral-torsional buckling instability of wood I-joists. However, no research was found related to the lateral-torsional buckling instability induced by individuals walking on the wood I-joists. Experimental testing demonstrated that workers cause lateral-torsional buckling instability in wood I-joists. Workers walking on unbraced or partially braced wood I-joists can induce axial and lateral forces as well as twist. However, wood I-joists have poor resistance to applied lateral and torsional loads and are susceptible to lateral-torsional buckling instability. Wood I-joists are designed to resist axial stresses on the flanges and shear stresses on the web while minimizing material used.

Wood I-joists have been replacing dimension lumber for many floor systems and a substantial number of roof systems in light-frame construction. Workers walking on wood I-joists on roofs and floors are prone to fall hazards. Recent research has shown that a significant number of the falls from elevation occur when laborers are working on unfinished structures. Lateral-Torsional Buckling Instability Caused by Individuals Walking on Wood Composite I-Joists

Ring forces and the bending moments in the irrigation tanks the cylinder theory