After an unfortunate accident at a local warehouse you have been contracted to d

Question

After an unfortunate accident at a local warehouse you have been contracted to determine the cause. A jib crane collapsed and injured a worker. An image of this type of crane is shown in the figure below. The horizontal steel beam had a mass of 90.20 kg per meter of length and the tension in the cable was T = 12950 N. The crane was rated for a maximum load of 454.5 kg. If d = 6.160 m, s = 0.486 m, x = 1.450 m and h = 2.250 m, what was the magnitude of WL (the load on the crane) before the collapse? What was the magnitude of force at the attachment point P? The acceleration due to gravity is g = 9.810 m/s2.

Been contracted to determine the cause. Type of crane is shown in the figure below of length and the tension in the cable was 54.5 kg. if d = 6.160 m, s = 0.486 m, (the load on the crane )before the collapse? The acceleration due to gravity is

Explanation / Answer

Tan? = h/(d-s) = 2.25/(6.16-0.486) = 0.3965

? = atan(0.3819) = 21.628 deg

Weight of beam Wb = (80*d)*g = 80*6.16*9.81 = 4829.776 N

This weight will act from mid-point of beam, i.e from d/2.

Balancing moments about P, Wl*(d-x) + 4829.776 *(d/2) = (TSin?)*(d-s)

Wl*(6.16 - 1.45) + 4606.776*(6.16/2) = (12.95*10^3 *Sin 21.628)*(6.16 - 0.486)

Wl = 2728.1.38 N

Balancing forces in the vertical direction: Fv = Wl + Wb - TSin?

Fv = 2728.1+ 4829.776 - (12.95*10^3 *Sin21.628) = 2792.39 N

Balancing force in horizontal direction: Fh = TCos? = 12.95*10^3 *Cos21.628 = 12030.14 N

Net force = ?(12030.14 ^2 + 2792.39^2) = 12349.83 N

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.