How must mobile cranes be positioned on barges?

Mobile cranes must be physically attached to the barge to ensure their stability and safety during operation. This attachment is crucial since cranes can exert significant lateral forces and moment loads due to the actions of lifting and swinging loads. Without a secure connection to the barge, there is a risk of tipping or shifting, particularly in situations where the barge encounters waves or currents.

Additionally, physically securing the crane helps to maintain its position and protects both the crane and the crane operator from potential hazards associated with unstable equipment. The required attachment can take various forms, such as bolts or other fastening mechanisms, which help distribute the load evenly and mitigate the risk of accidents.

Positions that rely solely on the crane's weight or that are floating without connections do not provide adequate safety measures and could lead to dangerous outcomes during lifting operations. Similarly, securing the crane with ropes would not provide the necessary stability and strength required for safe operation on a barge, as ropes can easily slip or break under load.