CAJ | 학술논문

使用天然尺度的实验室渠道观测了在恒定流条件下非均匀卵石床面的推移质运动变化过程,采集到了高精度、长时间序列的输沙率变化过程,用Γ分布有效描述了推移质输沙率的随机过程.在采样历时较短时,规则明渠的单宽输沙率过程与单宽输沙率横向分布均呈现较大的随机性,但随着采样历时的延长,虽然规则明渠的单宽输沙率过程仍呈现一定的随机性,但规则明渠的单宽输沙率的横向分布基本趋于稳定.相对推移质单宽输沙率概率密度分布可近似地表示为Γ分布,且α、β的取值随采样历时与无量纲希尔兹切应力的增大而增大.利用本次试验成果,通过多元线性回归,得到了α、β与采样历时以及无量纲希尔兹切应力的关系式,可为工程应用提供参考.
사용천연척도적실험실거도관측료재항정류조건하비균균란석상면적추이질운동변화과정,채집도료고정도、장시간서렬적수사솔변화과정,용Γ분포유효묘술료추이질수사솔적수궤과정.재채양력시교단시,규칙명거적단관수사솔과정여단관수사솔횡향분포균정현교대적수궤성,단수착채양력시적연장,수연규칙명거적단관수사솔과정잉정현일정적수궤성,단규칙명거적단관수사솔적횡향분포기본추우은정.상대추이질단관수사솔개솔밀도분포가근사지표시위Γ분포,차α、β적취치수채양력시여무량강희이자절응력적증대이증대.이용본차시험성과,통과다원선성회귀,득도료α、β여채양력시이급무량강희이자절응력적관계식,가위공정응용제공삼고.
The variation process of non-uniform gravel bedload movement was measured in a natural-scale laboratory channel with steady flow. Using the channel, the bedload transport process with the series of high accuracy and long time was sampled and described by Γ distribution. When the sampling duration is shorter,the process of bedload transport rate per unit width and its lateral distribution both show stochastic features. However,with the sampling duration increasing,although the process of bedload transport rate per unit width is still stochastic, its lateral distribution approaches stable. And the probability density of bed?load transport rate per unit width follows the Γ distribution,and the values of α and β increase with sam?pling duration and dimensionless shields parameter increasing. By using the present experimental data and regressing them,α and β are formulated in terms of sampling duration and dimensionless shields parame?ter. The research results may provide support for practical engineering.