Page 72 - 2025年第56卷第8期
        P. 72
     Research on local scour depth of tower foundation in sediment-laden
                                             rivers based on stochastic process
                                              1       2                3            4
                                    CAO Shuai ,LIU Lei ,ZHANG Hongwu ,ZHANG Qian
                                      s
                              (1. People’ Government of Dongshiduan Town,Xushui District,Baoding  072550,China;
                                          2. Ministry of Water Resources,Beijing  100053,China;
                                   3. Yellow River Research Center,Tsinghua University,Beijing  101309,China;
                                  4. Baoding Shangquan Municipal Engineering Co.,Ltd.,Baoding  071051,China)
                Abstract:The problem considered in this study is the local scour depth of transmission tower foundations,for which
                there is not yet unified calculation method in the sediment-laden rivers. Due to these problems,they are usually cal‐
                culated by the formula of bridge pier scour at present,which lead to significant deviations with the actual results,
                especially in sediment-laden river like the Yellow River. In order to reduce the potential natural hazards caused by
                inaccurate calculations,this study has established a theoretical formula for the local scour depth of tower foundation
                based on the fundamentals of stochastic process. As the forces acting on the sediment particle are uncertain during the
                process  of  scouring  around  the  tower  foundation,the  motion  of  each  particle  in  the  scour  pit  is  also  random,thus
                forming  a  stochastic  sediment  motion  field  within  the  scour  influence  range.  According  to  the  sediment  transport
                theory,there are specific transport laws for both bed-load and suspended-load on the riverbed near the tower founda‐
                tion.  These  laws  provide  the  theoretical  basis  for  determining  the  probability  density  of  positional  state  transition
                based on Markov random field and the statistical theory of sediment movement. The scour pattern of the tower founda‐
                tion,positional state model,and transfer-probability are discussed,and then the analytical formula for local scour
                depth is obtained by deriving the average dynamical equations of positional state. Meanwhile,by analyzing the physi‐
                cal mechanism of transition probability density,this study has determined the expression structures for the probabil‐
                ity density functions of time-averaged positional state transition. In light of the measured statistical data from natural
                sediment-laden rivers and physical modeling experiments,the relevant parameters in the calculation formula for local
                scour depth of tower foundation have been preliminarily determined. Finally,two sets of tower foundation scour model
                tests can be used as evidence to verify the proposed analytical formula for local scour depth,and the result indicates
                that the calculated values are consistent with the actual measurements.
                Keywords:stochastic  process;sediment-laden  river;tower  foundation;local  scour  depth;physical  modeling
                experiment
                                                                             (责任编辑:鲁  婧  韩  昆)
                — 1036   —





