Скачать или смотреть Precast Tunnel Installation

The clip begins with a crane hoisting a large, white, rectangular precast concrete box segment. The segment is suspended by four lifting hooks attached to the top corners. Below, in a deep trench that is reinforced with trench shoring (metal sheet piles and cross braces), two construction workers in hard hats guide the massive segment as it is carefully lowered into place.
The segment is being positioned to connect with several identical segments that have already been laid down in the trench, forming a continuous tunnel structure. The workers are ensuring the precise alignment and proper seating of the new segment with the adjacent pieces.