CONWEP blast loading pressures

The history of the incident and reflected pressures at various distances from the source can be computed from the following quantities: maximum incident and reflected pressures, arrival time, positive phase duration, and decay coefficients. For the purpose of verification these quantities are calculated independently for each of the range tests using empirical formulas of the CONWEP model given in Appendix A of Randers-Pehrson and Bannister (1997). The results from the range tests match the results from independent calculations exactly in all cases.

For the angle test the results of the maximum total pressure at various incident angles satisfy the equations for the total pressure given as a function of the incident pressure, the reflected pressure, and the incident angle in Acoustic and shock loads.

For the unit conversion tests the results of the incident and reflected pressures, when converted to SI units, are identical to the results from a similar test that uses SI units.

For the double-sided loading test zero total pressure is obtained for the surfaces with incident angles 90° and 270°. This result is correct since, in both orientations, the pressure on the SPOS and SNEG faces is equal to the incident pressure but the pressure loads act in the opposite directions. The total pressure for the surfaces with incident angles of 0° and 180° is equal in magnitude but opposite in sign. This result is correct since, in both orientations, the pressure is equal to the difference between the reflected pressure and the incident pressure and the pressure loads act in the opposite directions.