Figure 1 shows a tower crane with the properties listed in Table 1. The distance between the trolley and mast: Statics and Dynamics Course Work, NUN, UK

Question 1

Figure 1 shows a tower crane with the properties listed in Table 1. The distance between the trolley and mast x can change from 0 to dj (Figures 1 and 2).

Table 1: Specifications of the tower crane

• Draw the free body diagram of the tower crane and calculate the reactions at O when the mass of the lifted body 𝑚 = 5000 𝑘𝑔 and the distance 𝑥 = 20 m
• When 𝑚 = 5000 kg, find and plot the moment at O as a function of 𝑥, and determine the value of 𝑥 when the moment at O is zero
• If the magnitude of the maximum moment at O is 2,500 kN∙m and the magnitude of the maximum force at O is 1,650 KN, calculate the maximum mass of the body that the tower crane can lift regardless of the trolley location.
• When lifting heavy bodies with two points is required, a spreader beam is used (Figure 3). If 𝑤₁ = 0.7 m, 𝑤₂ = 1.4 m, 𝑚 = 1000 × (5 − 0.010 × 𝑆) 𝑘𝑔, and the mass of the spreader is negligible:
  1. Calculate the tension forces in the slings AB and CD when the lifted body is not tilted
  2. To prevent the body from tilting, what should be considered in the design and operation of the spreader beam?