Brackets, such as the one shown, are used in mooring small watercraft. Failure of such brackets is usually caused by bearing pressure of the mooring clip against the side of the hole. Our purpose here is to get an idea of the static and dynamic margins of safety involved. We use a bracket 1/4 in thick made of hot-rolled 1018 steel. We then assume wave action on the boat will create force F no greater than 1200 lbf.
(a) Identify the moment M that produces a shear stress on the throat resisting bending action with a €œtension€ at A and €œcompression€ at C.
(b) Find the force component Fy that produces a shear stress at the throat resisting a €œtension€ throughout the weld.
(c) Find the force component Fx that produces an in-line shear throughout the weld. (d) Find A, Iu , and I using Table 9€“2, in part.
(e) Find the shear stress τ1 at A due to Fy and M, the shear stress τ2 due to Fx , and combine to find τ .
(f) Find the factor of safety guarding against shear yielding in the weldment.
(g) Find the factor of safety guarding against a static failure in the parent metal at the weld.
(h) Find the factor of safety guarding against a fatigue failure in the weld metal using a Gerber failure criterion.

Transcribed Image Text:

Lin R -in dia 30° in 1 in