استفاده از داده های سری زمانی راداری در تعیین جابجایی سدهای خاکی (منطقه مورد مطالعه: سد خاکی ماملو)

ﻣﻬﻨﺪﺳﺎن ﺳﺎلﻫﺎﺳﺖ ﺑﻪ ﺗﻼش ﺑﺮای دﺳﺘﯿﺎﺑﯽ ﺑﻪ روﺷﯽ ﺑﻬﯿﻨﻪ ﺑﺮای ﭘﺎﯾﺶ ﺳﺎزهﻫﺎ ﺑﻪﻣﻨﻈﻮر ﺟﻠﻮﮔﯿﺮی از وﻗﻮع ﻓﺎﺟﻌﻪﻫﺎی ﺟﺒﺮانﻧﺎﭘﺬﯾﺮ ﭘﺮداﺧﺘﻪاﻧﺪ. ﯾﮑﯽ از اﯾﻦ ﺳﺎزهﻫﺎی ﻣﻬﻢ ﮐﻪ ﻧﯿﺎزﻣﻨﺪ ﭘﺎﯾﺶ ﻣﺪاوم اﺳﺖ، ﺳﺪ ﻣﯽﺑﺎﺷﺪ؛ ﭼﺮاﮐﻪ ﻧﺎﭘﺎﯾﺪاری ﺳﺪﻫﺎی ﺑﺰرگ و ﮔﺴﯿﺨﺘﮕﯽ آنﻫﺎ ﻋﺎﻣﻠﯽ ﺗﻬﺪﯾﺪﮐﻨﻨﺪه ﺑﺮای ﺟﺎن و ﻣﺎل اﻧﺴﺎنﻫﺎ ﺑﻪ ﺣﺴﺎب ﻣﯽ آﯾﺪ و اﺛﺮات زﯾﺴﺖ ﻣﺤﯿﻄﯽ ﻗﺎﺑﻞ ﻣﻼﺣﻈﻪای ﺑﻪ دﻧﺒﺎل ﺧﻮاﻫﺪ داﺷﺖ. ﻣﺴﺌﻠﻪ اﺻﻠﯽ در اﯾﻦ ﺗﺤﻘﯿﻖ، اراﺋﻪ روﺷﯽ ﮐﻢﻫﺰﯾﻨﻪ، ﺳﺮﯾﻊ و دﻗﯿﻖ ﺑﺮای ﻣﺤﺎﺳﺒﻪ ﺟﺎﺑﺠﺎﯾﯽ و ﺗﻐﯿﯿﺮﺷﮑﻞ ﺑﺪﻧﻪ ﺳﺪﻫﺎی ﺧﺎﮐﯽ ﻣﯽﺑﺎﺷﺪ. روشﻫﺎی ﻣﺨﺘﻠﻔﯽ ﺟﻬﺖ اﻧﺪازهﮔﯿﺮی ﺟﺎﺑﺠﺎﯾﯽ ﺑﺪﻧﻪ ﺳﺎزه ﺳﺪ وﺟﻮد دارد ﮐﻪ در ﻣﯿﺎن آنﻫﺎ اﺳﺘﻔﺎده از ﺗﮑﻨﯿﮏﻫﺎی ﺳﻨﺠﺶازدوری از ﺟﻤﻠﻪ ﺗﺪاﺧﻞﺳﻨﺠﯽ راداری ﺑﻪدﻟﯿﻞ ﻓﺮاﻫﻢ ﻧﻤﻮدن ﻣﺸﺎﻫﺪات ﮔﺴﺘﺮده و ﻣﻨﻈﻢ از ﺳﻄﺢ زﻣﯿﻦ ﻣﯽﺗﻮاﻧﺪ در اﻣﺮ اﻧﺪازهﮔﯿﺮی ﺟﺎﺑﺠﺎﯾﯽ و ﻧﺸﺴﺖ ﺳﺎزه ﺳﺪ ﻣﻔﯿﺪ واﻗﻊ ﺷﻮد. ﻣﻨﻄﻘﻪ ﻣﻮرد ﻣﻄﺎﻟﻌﻪ در اﯾﻦ ﺗﺤﻘﯿﻖ، ﺳﺪ ﺧﺎﮐﯽ ﻣﺎﻣﻠﻮ واﻗﻊ در اﺳﺘﺎن ﺗﻬﺮان ﻣﯽﺑﺎﺷﺪ. روش اﺳﺘﻔﺎده ﺷﺪه ﺑﺮای ﺑﺮآورد ﺟﺎﺑﺠﺎﯾﯽ ﺑﺪﻧﻪ اﯾﻦ ﺳﺪ، ﺗﮑﻨﯿﮏ ﭘﺮاﮐﻨﺸﮕﺮ داﺋﻤﯽ )psi( ﻣﯽﺑﺎﺷﺪ، دادهﻫﺎی ﻣﻮرد ﻧﯿﺎز در اﯾﻦ ﺗﺤﻘﯿﻖ، دادهﻫﺎی ﺑﺎﻧﺪ c و x ﺳﻨﺠﻨﺪهﻫﺎی sentinel-1a و cosmoskymed-x ﻣﯽﺑﺎﺷﺪ. در ﭘﺮدازش ﺳﺮی زﻣﺎﻧﯽ اﯾﻦ ﺗﺼﺎوﯾﺮ از ﮔﺮاف ﺳﺘﺎرهای و ﻣﺜﻠﺚﺑﻨﺪی دﻟﻮﻧﯽ اﺳﺘﻔﺎده ﺷﺪه و دو ﻣﺪل ﺧﻄﯽ و ﻏﯿﺮﭘﺎراﻣﺘﺮﯾﮏ ﺑﺮای ﺑﺮآورد ﺟﺎﺑﺠﺎﯾﯽ در ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺷﺪ. ﻧﺘﺎﯾﺞ ﺣﺎﺻﻞ ﺑﺎ اﻋﻤﺎل دو ﻣﺪل ﻣﺨﺘﻠﻒ ﺟﺎﺑﺠﺎﯾﯽ ﺑﺮرﺳﯽ ﮔﺮدﯾﺪه و در ﻧﻬﺎﯾﺖ ﻣﺪﻟﯽ ﮐﻪ دارای ﻫﻤﺪوﺳﯽ زﻣﺎﻧﯽ ﺑﺎﻻﺗﺮی ﺑﻮد، ﺑﻪﻋﻨﻮان ﻣﺪل ﻣﻨﺎﺳﺐ اﻧﺘﺨﺎب ﮔﺮدﯾﺪ و ﻣﺪل دﯾﮕﺮ ﮐﻨﺎر ﮔﺬاﺷﺘﻪ ﺷﺪ. در ﭘﺮدازش دادهﻫﺎی ﺳﻨﺠﻨﺪه sentinel-1a ﺳﺪ ﻣﺎﻣﻠﻮ ﻣﺪل ﻣﻨﺎﺳﺐ ﺑﺮای ﺟﺎﺑﺠﺎﯾﯽﻫﺎ، ﻣﺪل ﻏﯿﺮﭘﺎراﻣﺘﺮﯾﮏ و ﺑﺮای دادهﻫﺎی ﺳﻨﺠﻨﺪه cosmoskymed-x ﻫﻤﯿﻦ ﺳﺪ ﻣﺪل ﺧﻄﯽ ﺑﻪﻋﻨﻮان ﻣﻨﺎﺳﺐﺗﺮﯾﻦ ﻣﺪل اﻧﺘﺨﺎب ﮔﺮدﯾﺪ. ﺑﻪدﻟﯿﻞ ﻋﺪم ﺑﺮداﺷﺖ دادهﻫﺎی زﻣﯿﻨﯽ از ﺳﺪ ﻣﺎﻣﻠﻮ در ﺑﺎزه زﻣﺎﻧﯽ ﻣﺸﺘﺮک ﺑﺎ دادهﻫﺎی راداری، ﺑﻪﻣﻨﻈﻮر ارزﯾﺎﺑﯽ دﻗﺖ و اﺛﺒﺎت درﺳﺘﯽ ﻧﺘﺎﯾﺞ ﺑﺪﺳﺖآﻣﺪه، ﻧﺘﺎﯾﺞ دو دﺳﺘﻪ دادهی راداری cosmoskymed-x و sentinel-1a ﻣﺮﺑﻮط ﺑﻪ ﺳﺪ ﻣﺎﻣﻠﻮ ﺑﺎ ﯾﮑﺪﯾﮕﺮ ﻣﻘﺎﯾﺴﻪ ﺷﺪه و ﻫﻤﺨﻮاﻧﯽ ﺑﺴﯿﺎر ﺑﺎﻻﯾﯽ ﺑﯿﻦ ﻧﺘﺎﯾﺞ اﯾﻦ دﺳﺘﻪ داده ﻣﻼﺣﻈﻪ ﺷﺪ ﮐﻪ ﻣﯿﺰان rmse ﻣﺤﺎﺳﺒﻪ ﺷﺪه ﺑﺮای دادهﻫﺎیascاﯾﻦ دو ﺳﻨﺠﻨﺪه ﺑﺮاﺑﺮ ﺑﺎ 0,7703 ﻣﯿﻠﯿﻤﺘﺮ و ﺑﺮای دادهﻫﺎی dsc ﺑﺮاﺑﺮ ﺑﺎ 0,9551 ﻣﯿﻠﯿﻤﺘﺮ ﻣﺤﺎﺳﺒﻪ ﮔﺮدﯾﺪ ﮐﻪ اﯾﻦ ﻫﻤﺨﻮاﻧﯽ ﺑﺴﯿﺎر ﺑﺎﻻی ﻧﺘﺎﯾﺞ، اﻣﺮﯾﺴﺖ ﮐﻪ ﻣﯽﺗﻮاﻧﺪ دﻟﯿﻠﯽ ﺑﺮ درﺳﺘﯽ ﻧﺘﺎﯾﺞ اﺳﺘﺨﺮاج ﺷﺪه ﺑﺎﺷﺪ.

monitoring the earth-fill dams displacement by using the time series radar data (case study: mamlu dam)

with increasing the number of large engineering structures in cities, experts are looking for a good solution for monitoring these structures to avoid great financial and human damages. from the past, leveling and ground surveying were carried out to measure the deformation of structures and ground displacements along the vertical direction; but these measurements are time-consuming and costly. also, the using of precision instruments and deformation sensors are not suitable because of their high cost, time-consuming and complexity.due to the ability of radar images and radar interferometry techniques in the field of monitoring the ground displacement, in this research, we are looking for evaluating the potential of this method for monitoring the dam deformation and displacements. to achieve this goal, we used two sets of radar data which are cosmoskymed-x and sentinel-1a.  in the time series processing of these images, the psi method was selected then the star graph and deloney triangulation were used. in the next step, we used both linear and nonparametric models for displacement estimation. the results were evaluated by applying two different displacement models and finally, the model with higher temporal coherence was selected as the appropriate model and the other model was discarded. in processing the mamlu dam images, the appropriate model for monitoring the displacements with s-1a radar data was the nonparametric model and for csk data was linear model.due to the lack of ground data collection from mamlu dam in the same period of time with radar data, to evaluate the accuracy and proof the obtained results, the results of two radar data sets (csk and s-1a) were compared with each other and a very high agreement was observed between the results of these data sets that the amount of rmse calculated for asc data of these two sensors is equal to 0.7703 mm and for dsc data was calculated 0.9551 mm, which is a very high consistency of the results, which can be a reason for the accuracy of the extracted results.