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| Field tests and numerical simulations of blast-induced crater in wet sands |
| WANG Weiguo1，2，CHEN Yumin1，2，YANG Gui1，2，LIU Yanchen1，2 |
(1. Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering，Hohai University，Nanjing，
Jiangsu 210098，China；2. College of Civil and Transportation Engineering，Hohai University，Nanjing，Jiangsu 210098，China) |
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Abstract Blast-induced craters in wet soils can cause fatal disasters in geotechnical works，especially for crest of a dam and shallow locations of a foundation. A series of field explosion tests in wet sand were carried out to study the influencing factors on crater sizes. At the same time，a coupled SPH-FE numerical method was established to assess the results from field tests. The assessments show that the final crater in wet sand can be classified into three different types：camouflet，collapse crater and cast blasting crater. A cast blasting crater will be found at scaled burial depth of 1.5 m/kg1/3 or less. The critical scaled burial depth for camouflet is about 2.3 m/kg1/3 in wet sand. Diameters of the apparent crater from the tests and the true crater from simulations presented a good consistency with results predicted by ConWep. Bulge movement modelling with SPH particles was basically consistent with that in the field test，which means the numerical method can be used to predict the apparent crater sizes well in a real project. Density and strength of sand material have little influence on crater diameter within a tolerance of 10%. An empirical equation of crater diameter is proposed in terms of explosive mass and burial depth，based on dimensional analysis and the results from field tests.
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2016, Vol. 35 
