جستجوی مقالات مرتبط با کلیدواژه "ضریب فشار آب حفره ای" در نشریات گروه "عمران"

In this study, the ability of WCA-ANN hybrid algorithm to model the pore water pressure coefficient in the body of Kabudwal dam at the time of construction was investigated and the effective features were identified. Therefore, five features including fill level, time, reservoir level, dewatering rate and fill speed during the 4-year statistical period were selected as the input of the model. By running the hybrid algorithm and feature selection method, the two features of fill level and time at points RU19.1  and   RU19.2 have the greatest impact on modeling the pore water pressure coefficient. In addition to the above two features, in the points of the middle axis , the features of fill speed and reservoir level with error value (MSE) equal to 0.00006 and in points close to the dam reservoir, dewatering level and dewatering rate with error value equal to 0.00004 are effective in modeling the pore water pressure coefficient. The results showed that at points close to the dam axis, the fill level and at points farther from the middle axis construction time (with high sensitivity coefficient) was recognized as the most important features in modeling the pore water pressure coefficient with artificial intelligence models.

The main role ofcore in earth dams is to reduce and control the seepage flow through the dam. In order to achieve this purpose، the core material is usually selected from pure or mixed clays. Due to very small coefficient of permeability، the clay cores can prevent water leakageeasily. However، pore water pressures developed inside the core during construction، can not be dissipated quickly. As a result، increasing the rate of embankment filling during the construction stage، may lead to large development of the pore pressure inside the core. In this study،based on a hardening elasto-plastic constitutive model، the total stresses and pore pressures inside the core of MASJED-E-SOLEYMAN rockfill dam، are calculated using the PLAXIS software during the construction and first reservoir filling stages. The analysis is in term of effective stress coupled with consolidation analysis. In order to verify the result of the numerical analysis، the measurment data from installed instruments intherockfill dam have been compared with the numerical results. This comparsion shows that the numerical analysis results are in a good agreement with the instrument results. Excess amount of pore pressures in the core of this dam is due to very small coefficient of permeability and high rate of embankment filling.