CAJ | 학술논문

近年来，随着来水来沙条件的改变，南京八卦洲汊道左汊衰退速率又有所加快，并已多次观测到12％左右的分流比。采取一定的工程措施可以对左汊的分流比进行改善，但工程在改变汊道首部分流比的同时也改变了分沙比。分沙比的改变对于整治工程的实施效果，以及下游河道的走势，特别是左汊的河床冲淤变化有一定的影响。针对改善左汊分流比的工程措施，运用二维水沙数学模型，计算分析了导流坝、切滩、疏浚等工程措施对汊道河床冲淤的影响。结果显示，3个月冲淤计算后，工程措施对左汊分流比均有较大改善，且在工程附近河床的冲淤也有较明显的变化。
근년래，수착래수래사조건적개변，남경팔괘주차도좌차쇠퇴속솔우유소가쾌，병이다차관측도12％좌우적분류비。채취일정적공정조시가이대좌차적분류비진행개선，단공정재개변차도수부분류비적동시야개변료분사비。분사비적개변대우정치공정적실시효과，이급하유하도적주세，특별시좌차적하상충어변화유일정적영향。침대개선좌차분류비적공정조시，운용이유수사수학모형，계산분석료도류패、절탄、소준등공정조시대차도하상충어적영향。결과현시，3개월충어계산후，공정조시대좌차분류비균유교대개선，차재공정부근하상적충어야유교명현적변화。
In recent years , the recession of the left branch of Baguazhou braiding channels in Nanjing of Yangtze River has accelerated with the variation of water and sediment conditions , and the split ratio of the left branch has reduced to 12% . River engineering treatments and structures can improve the split ratio of the left branch , while the diversion ratio of sediment will be changed too , which may generally affect the improvement effect of engineering measures and the trend of downstream river channel , especially the deposition of the left branch . For the engineering measures to improve the split ratio of the left branch , this paper analyzes the impact of diversion dikes and dredge in the left branch on the progress of riverbed deposition with a 2-D flow and sediment mathematical model . The results show that split ratio of the left branch generally increase and there is also significant erosion around the engineering structures . It can provide some advice for the further improvement of engineering measures .