Blast damage assessments

In the first approach, a vapor cloud s potential explosive power is proportionally related to the total quantity of fuel present in the cloud, whether or not it is within flammable limits. This approach is the basis of conventional TNT-equivalency methods, in which the explosive power of a vapor cloud is expressed as an energetically equivalent charge of TNT located in the cloud s center. The value of the proportionality factor, that is, TNT equivalency, is deduced from damage patterns observed in a large number of vapor cloud explosion incidents. Consequently, vapor cloud explosion-blast hazard assessment on the basis of TNT equivalency may have limited utility. 

Objects in the vicinity of an explosion can often serve as useful post-blast witnesses. Thus for large explosions damage to structural elements of buildings, street furniture, motor vehicles, and glazing can all prove informative. A number of authors have published studies that provide guidance on both damage assessment techniques and interpretation of the data [2-7]. 

Although far-field damage is not a severe problem at the excavation sites where the blasting faces moves away and vibration gets attenuated substantially, the authors observed that it is an acute problem when the rock mass is subjected to repeated vibrations due to multiple excavations in the vicinity as in the case of multiple tunnels and caverns. In view of the above arguments it was decided to go for the investigation of both near field and far field damage assessments at the Lohari Nag Pala Hydroelectric Power Project (LNPHPP)... 

Meyer, T., Drum, P. G. (1996). Fragmentation and Rock mass Damage Assessment - Sunburst Excavator and Drill and Blast. In Proceedings of the HARMS 1996 - Rock Mechanics Tools and Techniques (pp. 609-617). 

The probit function approach can be used for fast damage assessment of blast effects of high explosive events. In the literature is the only parameterization of blast effects that can be interpreted as a probability distribution function in terms of physical parameters. In this sense we found only one probability distribution that is used in literature for the description of blast effects. 

Response to Blast Waves The effect of blast waves upon eqmp-ment and people is difficult to assess because there is no single blast wave parameter which can fully describe the damage potenti of the... 

Response to Blast Waves The effect of blast waves upon equipment and people is difficult to assess because there is no single blast wave parameter which can fully describe the damage potential of the blast. Some targets respond more strongly to the peak incident overpressure and others to the impulse (J p dt) of the blast. The blast parameters are usually based on the conservative assumption that the... 

It was required to measure the blast vibrations in the near-field as well as far-field zones with respect to blast site to assess the rock mass damage. Therefore a room of about 0.5m (lmxlmx0.5m) was excavated inside the sidewall for installation... 

D.J. Lewis (a) Unconfined vapor cloud explosions. Progr. Energy Comb. Sci. 6(2), 151-165 (1980) (b) Estimating damage from aerial explosion type incidents. Problems with detailed assessment and an approximate method. Paper at Euromech-139, Aberysthwith, 1981 (c) Condensed phase explosions and their blast characteristics. Paper at Euromech-139, Aberysthwith, 1981... 

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