水利学报
水利學報
수리학보
2015年
3期
315-325
,共11页
郑珊%谈广鸣%吴保生%王开荣
鄭珊%談廣鳴%吳保生%王開榮
정산%담엄명%오보생%왕개영
黄河口%侵蚀基准面%滞后响应%河长%比降
黃河口%侵蝕基準麵%滯後響應%河長%比降
황하구%침식기준면%체후향응%하장%비강
Yellow River Delta%base level%delayed response%channel length%channel slope
本文分析了黄河口的演变特征及其对利津3000 m3/s同流量水位的影响。黄河口每次改道后尾闾河道的河长突然缩短,比降陡增,之后河长以先快后慢的速率增长,尾闾河道比降则呈指数衰减,经过约5~6年调整至平衡比降,其变化过程反映了典型的河床演变滞后响应特性。基于黄河口河道的演变特征,提出了河口河道水位和纵比降变化的概化模式,并采用滞后响应模型建立了河口河道同流量水位的计算方法,较好地计算了1954—2012年间黄河下游利津3000 m3/s同流量水位的变化过程。该计算方法不仅考虑了河床演变的滞后响应特性,而且反映了来水来沙和河道淤长与蚀退对利津同流量水位的共同影响,能够连续地模拟河口淤积延伸及改道过程中河口河道特征水位的长期变化过程。研究成果可为分析黄河口淤积延伸与下游河道相对侵蚀基准面的变化关系提供参考。
本文分析瞭黃河口的縯變特徵及其對利津3000 m3/s同流量水位的影響。黃河口每次改道後尾閭河道的河長突然縮短,比降陡增,之後河長以先快後慢的速率增長,尾閭河道比降則呈指數衰減,經過約5~6年調整至平衡比降,其變化過程反映瞭典型的河床縯變滯後響應特性。基于黃河口河道的縯變特徵,提齣瞭河口河道水位和縱比降變化的概化模式,併採用滯後響應模型建立瞭河口河道同流量水位的計算方法,較好地計算瞭1954—2012年間黃河下遊利津3000 m3/s同流量水位的變化過程。該計算方法不僅攷慮瞭河床縯變的滯後響應特性,而且反映瞭來水來沙和河道淤長與蝕退對利津同流量水位的共同影響,能夠連續地模擬河口淤積延伸及改道過程中河口河道特徵水位的長期變化過程。研究成果可為分析黃河口淤積延伸與下遊河道相對侵蝕基準麵的變化關繫提供參攷。
본문분석료황하구적연변특정급기대리진3000 m3/s동류량수위적영향。황하구매차개도후미려하도적하장돌연축단,비강두증,지후하장이선쾌후만적속솔증장,미려하도비강칙정지수쇠감,경과약5~6년조정지평형비강,기변화과정반영료전형적하상연변체후향응특성。기우황하구하도적연변특정,제출료하구하도수위화종비강변화적개화모식,병채용체후향응모형건립료하구하도동류량수위적계산방법,교호지계산료1954—2012년간황하하유리진3000 m3/s동류량수위적변화과정。해계산방법불부고필료하상연변적체후향응특성,이차반영료래수래사화하도어장여식퇴대리진동류량수위적공동영향,능구련속지모의하구어적연신급개도과정중하구하도특정수위적장기변화과정。연구성과가위분석황하구어적연신여하유하도상대침식기준면적변화관계제공삼고。
This study analyzed the characteristics of the evolution of the Yellow River delta and its impact on water stage at Lijin at a discharge of 3 000 m3/s (denoted by H3000). Every time after channel avulsion at the Yellow River delta, the river length downstream of the diversion point was suddenly shortened and chan?nel slope increased steeply, then channel length increased with a decreasing rate while channel slope de?creased with a rate decaying exponentially with time and adjusted to equilibrium slope after 5~6 years. Such phenomenon typically reflected the significant characteristic of delayed response of the fluvial system. Based on these characteristics of the evolution of Yellow River delta channel, generalized models for the changes of channel slope and water surface at the delta channel were proposed. Based on the proposed con?ceptual models, equations for calculating water stages at the same discharge along the delta channel were developed by using the delayed response model for modelling morphological responses of fluvial rivers to perturbations. H3000 at Lijin during 1954 and 2012 was calculated well. The proposed methods consider the characteristic of delayed response of fluvial system and the impacts of water and sediment conditions and delta evolution on the changes of the local base level of the Lower Yellow River(LYR), which makes them applicable to the whole evolution processes of the degradation, extension,swift and avulsion of the del?ta channel. This study provides references for studying the relationship between delta extension and accre?tion and the changes of local base level of the LYR.