【摘要】 泥沙问题是三峡工程的关键技术问题之一,在三峡工程论证、设计、建设和运行的各个阶段,针对重大的工程泥沙问题进行了系统和持续的研究,提出了相应的解决方案.本文对三峡工程采用的减缓水库泥沙淤积与保持长期有效库容的运用方式、水库变动回水区港口与航道泥沙问题治理措施、枢纽引航道与电站引水防沙布置方案、坝下游河道长距离冲刷预测、河势变化及对航道影响的对策等进行了分析总结.2003年三峡水库蓄水运用以来水库淤积和坝下游河道冲刷情况分析表明:水库泥沙主要淤积在死库容,有效库容损失较少,库区航运条件得到大幅改善;坝下游河道发生长距离冲刷,冲刷强度不断向下游发展,河势总体基本稳定;长江中下游航道经过治理,航道维护水深有了较大提高.三峡工程泥沙问题的解决方案已得到初步检验,泥沙问题及其影响基本未超出论证与初步设计的预测.本文还对今后一段时期需要进一步研究的泥沙问题提出了建议,包括水库优化调度、坝下游河道冲刷、江湖关系变化和长江口演变等.更多还原

【Abstract】 The sediment problem is one of the key technical problems of the Three Gorges Project(TGP). Systematic and continuous studies on major engineering sediment problems have been carried out during various stages of the feasibility study, design, construction and operation of the TGP, and the corresponding solutions have been put forward. In this paper, the sediment problem solutions for the TGP are analyzed and summarized including: the operation mode of "storing clear and releasing muddy" to mitigate reservoir sedimentation and maintain long-term effective capacity; measures to control sediment problems in the port and navigation channel in the reservoir backwater area; the sediment control layout plan of the navigation approaching channel and the water diversion for the power station;the prediction of long-distance scour and the changes in river regime for the downstream channel of the dam; and the impacts of the TGP to the navigation channel and the countermeasures. It shows by analyzing the field measured reservoir sedimentation and downstream channel erosion since the TGP impoundment in 2003 that: the sediment has been mainly deposited in the dead storage, the loss of effective storage capacity is minor and the navigation conditions has been significantly improved; the river regime downstream of the TGP has been quite stable in general, with long-distance channel erosion and the erosion continue propagating downstream;and the navigation channel depth has been maintained after river management in the middle and lower reaches of the Yangtze River.The TGP sediment problem solutions have been preliminarily examined, and it shows that the sediment problems and their impacts have been within the predictions of the feasibility study and preliminary design. Due to the long-term and contingency of sediment problems, the hydrology and sediment monitoring should be continued for a considerable period of time, and the studies on reservoirs optimal operation, downstream channel erosion, management of river-lake relation, and the evolution of the Yangtze River estuary and other problems should be strengthened.更多还原