Theoretical Analysis And Test Research On Shock Wave Of Underwater Explosion

Chinese engineering blasting industry for long-and medium-term scientific andtechnological development planning（2006-2020）,which was organized and setted upby China Society of Engineering Blasting,pointed out that: In the21th century, ourshipping and port construction are developing rapidly. With the development goingdeep into abyssal sea gradually, the blasting scale and the detonation dose will alsoincrease. Meanwhile, the environmental damage caused by the expanding of the scaleof the project will become an urgent problem to be solved. Underwater explosionshock wave is an important hazards of underwater explosions, it has the largeamplitude, far dissemination and a short duration of action. Especially for underwaterdrilling blasting, the underwater topography, geological conditions, water flow, waterdepth, construction methods, construction quality and so on that will have an impacton the shock wave generation and propagation.so the monitoring technology and theanalysis of propagation rules are significant.Based on that a large amount of reference at home and abroad has been read andthe theoretical studies, technical progress at home and abroad were analyzed. Thispaper is based on the project Research and application of underwater drilling blasting,with the underwater shock wave sensor which was developed by PCB company inAmerica, we have designed a small pilot experiment. Based on the small pilotexperiment, we completed the monitoring mission on Phase II expansion project ofwaterway dredging in Gulei Xiamen. Waveform curve of shock wave and about40groups of pressure data of underwater group of satchel charges were measured.Through the test, it is confirmed that the test system and test method in this paper isapplicable. By analysising the test data, we know that the characteristics of shockwave and its attenuation law,which the single dosage is110kg~500kg while the totaldosage is730kg~4710kg and the blasting distance is from74.5m to220m.Thisconclusion could be used to modify the classical semi-empirical formula of thepressure, for reference.A series of blasting water hammer wave data has been tested, including the flatwater, dynamic water, bare explosion and underwater drilling blasting. Potter and theattenuation law of them has been researched and the safe distances, which will ensurethe safety of a ship or a man, have also been given. The results are of greatsignificance for guiding the design to underwater blasting and assessment ofenvironmental safety.