3658

3457

كارشناسي ارشد

آب

اصفهان : دانشگاه صنعتي اصفهان ، دانشكده عمران

1386

شانزده ، 161، [II] ص.: مصور ، نمودار ، جدول

ص.ع.: به فارسي و انگليسي

حميد رضا صفوي ، محمد رضا مجد زاده طباطبائي

5/15/86

محمد رضا چمني

مهندسي عمران

ID3457

به فارسي و انگليسي : قابل رويت در نسخه ديجيتال

AbstractIn morphological dynamic and restoration of rivers subjects dominant discharge ofchannel forming discharge is applied as design discharge This dominant dischargecan be based on field measurements a chosen recurrence interval of flooding orrelated to the effective discharge Equilibrium of channel form is affected by flowenergy and sediment resistance against erosion and effective discharge is defined asthe flow which transports the most sediment over the period of the record Anychanges in the morphology of a river other than by river engineering works mustresult from a local imbalance in the sediment budget When in regime the river musthave adjusted its bankfull morphology to transmit the total sediment load suppliedfrom upstream such that over a period of years there is no net erosion or deposition The flow transporting the bulk of the sediment is often referred to as the effectivedischarge since any changes in either the flow or sediment transport regime of theriver will alter its value and cause instability and adjustment to the changed condition This study is considered three methods such as rating curve mean approach andexcess stream power for effective discharge estimation by measured suspended loadand calculated bedload for 11 gravel bed and 7 sand bed rivers In this context factorsare also considered by which this may be computed more accurately Herein differentmethods of estimating the effective discharge are described and analytical solutionsare derived These analytical solutions are easy to apply and can be used to predict theeffective discharge under existing conditions and the historic flow records Thesesolutions can be used to explain some of the discrepancies between different methodsof estimating the effective discharge A comparison of analytical solutions andobserved results are made It can be concluded that analytical solutions are applicablewhere no observed data for direct calculations is available The results of this studyshow different trend for gravel and sand bed rivers In gravel bed rivers the effectivedischarge for the bedload tends to exceed bankfull discharge and effective dischargeof suspended load Conversely in sand bed rivers effective discharge for bedload andsuspended load have the same value and equal with bankfull discharge

حميد رضا صفوي ، محمد رضا مجد زاده طباطبائي

محمد رضا چمني