جستجوی مقالات مرتبط با کلیدواژه « Empirical model » در نشریات گروه « مکانیک »

In this paper, a non-dimensional analysis approach has been used to propose two empirical equations based on dimensionless numbers to predict the maximum transverse permanent deflection-thickness ratio of single-layered quadrangular plates under uniformly and locally distributed dynamic loading. In the presented dimensionless numbers, the effect of plate geometry, the impulse of the applied load, the mechanical properties of the plate, the strain-rate sensitivity, and the loading radius have been considered. To validate the empirical models, eight series of conducted experiments and 267 data points in the state of the art over the past forty years have been used. The obtained results show good agreement between the model prediction results and the experimental values so that in the total of 117 experimental data for uniform loading, 94% (110 data) and 98% (115 data) of the data points were distributed in the ±10% and ±20% error range, respectively. Besides, in the total of 150 experimental data for localized loading, 83% (124 data) and 97% (146 data) of data points were distributed in these two ranges, respectively. The results also showed that assuming the material constants as variables based on the plate thickness, in the Cooper-Symonds constitutive equation improves the prediction accuracy of the empirical models so that only 6% and 12% of the data for uniform and localized loading respectively, are not within the 10% error range.

In this paper, a non-dimensional analysis approach has been used to propose three empirical equations based on dimensionless numbers to predict the maximum transverse permanent deflection-thickness ratio of single-layered circular plates under uniformly and locally distributed dynamic loading. The effect of plate geometry, the impulse of applied load, mechanical properties of the plate, the strain-rate sensitivity, the load radius, and the stand-off distance was considered. In order to validate the empirical models, fourteen series of conducted experiments and 562 data points in the state of the art over the past forty years have been used. The obtained results showed good agreement between the model prediction results and the experimental values so that in total 338 experimental data for uniform loading, 75% (255 data) and 94% (318 data) of the data points were distributed in the ±10% and ±20% error range, respectively. In addition, in total 108 experimental data for localized loading without using stand-off distance, 59% (64 data) and 92% (99 data) of data points were distributed in these two ranges, respectively. For the localized loading using the stand-off distance, 68% (79 data out of 116) and 94% (99 data out of 116) of the data points were distributed in the ±10% and ±20% error range, respectively.