Abstract: The influence on dolphins imposed by blasting during construction of Xiang’an subsea tunnel in Xiamen is studied by means of theoretical calculation and field monitoring. Proper controlledblasting program is established for the construction of the subsea tunnel. Countermeasures, such as minimizing the blasting advance rate, preserving the smoothblasting layer, properly arranging the blasting holes, well controlling the total charging quantity and the individual ignition explosive quantity, are taken to minimize the peak value of the stress wave. The calculation and monitoring results show that both the peak value and the grade of the acoustic pressure 200 m beyond the blasting source are small. Therefore, the distance of 200 m is taken as the safe distance for the protection of the dolphins. It is proposed that the monitoring of the dolphins in the sea area that may be influenced should be strengthened and that, when necessary, the dolphins should be expelled to safe areas by means of ships, acoustic waves or electromagnetic waves.

Key words: Xiang’an subsea tunnel, controlled blasting, dolphin