Elements tested
- C3D4
- C3D6
- C3D8
- C3D10M
- S3R
- S4RS
ProductsAbaqus/Explicit Elements tested
Features testedIncident, reflected, and total pressures of the CONWEP model. Problem descriptionPressure output from the CONWEP blast loading model is verified in this set of tests. In each test all degrees of freedom of the loading surface are constrained, and the pressure is obtained by summing the reaction forces at all the nodes on the surface and dividing the sum by the surface area. The pressure calculated from the reaction forces corresponds to the total pressure, which is a function of the incident pressure, the reflected pressure, and the incident angle. The total pressure corresponds to the incident pressure and the reflected pressure when the loading surface is given at incident angles of 180° and 0°, respectively. The variation of the incident and reflected pressures with range is verified in the range tests, in which loading surfaces at incident angles of 180° and 0° are placed at various distances from the source. The variation of the total pressure with the incident angle is verified in the angle test, in which multiple loading surfaces located at the same distance from the source are given at different incident angles. Unit conversion is verified in the unit conversion tests, in which non-SI mass units (for the charge) and analysis units are used. Units of ton-mm-sec-MPa and lb-ft-sec-psf are considered in the tests. For shell elements CONWEP blast loading pressure can be applied to both the SPOS and SNEG faces of the elements. Double-sided loading is verified in the test in which doubled-sided loading surfaces are orientated at incident angles of 0°, 90°, 180°, and 270°. Results and discussionThe 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. Input filesElement tests
Range tests
Angle test
Unit conversion tests
Double-sided loading test
References
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