MecMovies 4.0 : M4.3: Load Capacity of Beam-strut Structure

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The figure shows the free body diagram of the beam. The reaction forces at C are C subscript x and C subscript y directed horizontally to the right and vertically upwards respectively. The load on the beam is 3.6 meters times w kilo newton per meter and it acts at a distance of 1.8 meters from C. The force along the support rod directed away from the point B is F subscript 1 at an angle of 35 degrees with the horizontal.

Solve the moment equation for F₁ in terms of w:

$\sum_{} M_{C} = - (3.6 m) (w kN/ m) (1.8 m) - (5.0 m) F_{1} \sin (35 . 0^{\circ}) = 0$

$∴ F_{1} = - (2.2595 m) (w kN/ m)$

$\sum_{} F_{x} = C_{x} - F_{1} \cos (35 . 0^{\circ}) = 0$

$\sum_{} F_{y} = C_{y} - (3.6 m) (w kN/ m) - F_{1} \sin (35 . 0^{\circ}) = 0$