رﻓﺘﺎرﻧﮕﺎري ﺳﺪ در زﻣﯿﻨﻪ ﻧﺸﺖ ﺗﺤﺖ اﺛﺮ ﺗﺤﮑﯿﻢ ﺑﺎ روش اﺟﺰاءﻣﺤﺪود ﻣﻄﺎﻟﻌﻪ ﻣﻮردي: ﺳﺪ ﮐﺮﺧﻪ

Monitoring Seepage through Dam under Consolidation Using the Finite Element Method, Case Study: Karkheh Dam

رﻓﺘﺎرﻧﮕﺎري ﺳﺪ ﺧﺎﮐﯽ ﺑﻪ ﺑﺮرﺳﯽ ﻋﻤﻠﮑﺮد ﺳﺪ در ﻣﺮاﺣﻞ ﻣﺨﺘﻠﻒ ﺳﺎﺧﺖ، اوﻟﯿﻦ آﺑﮕﯿﺮي و دوران ﺑﻬﺮهﺑﺮداري اﻃﻼق ﻣﯽﺷﻮد ﮐﻪ در زﻣﯿﻨﻪﻫﺎي ﻣﺨﺘﻠﻔﯽ ﻧﻈﯿﺮ ﺗﺤﻠﯿﻞ ﻧﺸﺖ و ﻧﺸﺴﺖ ﻣﯽﺗﻮاﻧﺪ ﺻﻮرت ﭘﺬﯾﺮد. در اﯾﻦ ﺗﺤﻘﯿﻖ، رﻓﺘﺎرﻧﮕﺎري ﺳﺪ در زﻣﯿﻨﻪ ﻧﺸﺖ ﺑﻪ روش اﺟﺰاءﻣﺤﺪود ﺗﺤﺖ ﺳﻨﺎرﯾﻮﻫﺎﺋﯽ ﺑﺎ ﻓﺮض ﺟﺮﯾﺎن اﺷﺒﺎع ﮐﺎﻣﻞ، ﺟﺮﯾﺎن اﺷﺒﺎع-ﻏﯿﺮاﺷﺒﺎع و ﺟﺮﯾﺎن اﺷﺒﺎع-ﻏﯿﺮاﺷﺒﺎع ﺑﺎ اﺛﺮ ﺗﺤﮑﯿﻢ در دو ﺣﺎﻟﺖ ﻣﺎﻧﺪﮔﺎر و ﻏﯿﺮﻣﺎﻧﺪﮔﺎر ﺑﺮ روي ﺳﺪ ﻣﺨﺰﻧﯽ ﮐﺮﺧﻪ اﻧﺠﺎم ﮔﺮﻓﺖ. ﺑﺎ ﻫﺪف ﺗﺪﻗﯿﻖ ﭘﺎراﻣﺘﺮﻫﺎ و ﻧﺘﺎﯾﺞ ﺗﺤﻠﯿﻞﻫﺎ ﺑﺎ ﺷﺮاﯾﻂ واﻗﻌﯽ ﺳﺪ از آﻣﺎر و اﻃﻼﻋﺎت 17ﺳﺎﻟﻪ ﭘﯿﺰوﻣﺘﺮﻫﺎي ﻣﻮﺟﻮد در 5 ﻣﻘﻄﻊ از ﺑﺪﻧﻪ و ﺗﮑﯿﻪﮔﺎه ﺳﺪ اﺳﺘﻔﺎده ﺷﺪه اﺳﺖ. ﺳﭙﺲ آﻧﺎﻟﯿﺰ ﺗﺮاوش ﺷﺎﻣﻞ ﮐﺎﻟﯿﺒﺮاﺳﯿﻮن و اﻋﺘﺒﺎرﺳﻨﺠﯽ ﻣﺪل ﻋﺪدي در دو ﺣﺎﻟﺖ دوﺑﻌﺪي و ﺳﻪﺑﻌﺪي ﺑﺎ اﺳﺘﻔﺎده از ﻧﺮم اﻓﺰارﻫﺎي Seep/w و Seep3D ﺗﺤﺖ ﺳﻨﺎرﯾﻮﻫﺎي درﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺷﺪه اﻧﺠﺎم ﭘﺬﯾﺮﻓﺖ و در ﻧﻬﺎﯾﺖ ﻣﺪل ﻋﺪدي ﮐﺎﻣﻞ در زﻣﯿﻨﻪ ﻧﺸﺖ ﻣﻄﺎﺑﻖ ﺷﺮاﯾﻂ واﻗﻌﯽ ﺳﺪ ﮐﺮﺧﻪ ﺑﺪﺳﺖ آﻣﺪ. ﻧﺘﺎﯾﺞ ﺣﺎﮐﯽ از آن اﺳﺖ ﮐﻪ ﺗﺤﻠﯿﻞ ﺳﻪﺑﻌﺪي ﺟﺮﯾﺎن در ﺣﺎﻟﺖ ﻏﯿﺮﻣﺎﻧﺪﮔﺎر ﺑﺎ اﺛﺮ ﺗﺤﮑﯿﻢ، ﻧﺴﺒﺖ ﺑﻪ ﺗﺤﻠﯿﻞ دوﺑﻌﺪي ﺑﺪون اﺛﺮ ﺗﺤﮑﯿﻢ دﻗﯿﻖﺗﺮ و ﺑﻄﻮر ﻣﯿﺎﻧﮕﯿﻦ ﺧﻄﺎي آن 23/5 درﺻﺪ ﮐﻤﺘﺮ از ﺣﺎﻟﺖ دوﺑﻌﺪي ﻣﯽﺑﺎﺷﺪ.

The monitoring of an earth dam refers to the dam’s performance in different construction stages, starting with impoundment followed by the exploitation period, which can be achieved in different fields such as seepage and subsidence analysis. This research analyzed Karkheh storage dam’s seepage behavior using the finite element method under various scenarios assuming saturated flow, saturated-unsaturated flow, and saturated-unsaturated flow under consolidation in steady and unsteady conditions. The 17-year data obtained from the Karkheh dam’s piezometer instrumentation in five sections of the dam’s body and foundation were used to improve the accuracy of the parameters and adapt the analyses results to the actual dam conditions. Subsequently, seepage analysis comprising calibration and validation of the numerical model in two-dimensional and three-dimensional states using Seep/w and Seep3D software was conducted under the considered scenarios. Finally, a complete numerical model was obtained based on the actual dam conditions. The results show that three-dimensional flow analysis in the unsteady state under consolidation is more accurate than the twodimensional state with a 23.5% lower error rate than the 2D approach.