Describir: Les grues a tour nécessite et dangers de leur utilisation

  ______     ___      ______    _____    _____      _____    _    _   
 /_____//   / _ \\   /_   _//  |  ___|| |  __ \\   |  ___|| | |  | || 
 `____ `   / //\ \\    | ||    | ||__   | |  \ ||  | ||__   | |/\| || 
 /___//   |  ___  ||  _| ||    | ||__   | |__/ ||  | ||__   |  /\  || 
 `__ `    |_||  |_|| /__//     |_____|| |_____//   |_____|| |_// \_|| 
 /_//     `-`   `-`  `--`      `-----`   -----`    `-----`  `-`   `-` 
 `-`                                                                  
 _    _   
| || | || 
| || | || 
| \\_/ || 
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