Abstract: Bearing capacity is an important basis for social and economic development planning, but the connotation of waterway bearing capacity is not yet clear, and there is also lack of evaluation research on waterway bearing capacity. The analysis of the definition of various bearing capacity showed that its connotation included four elements: bearing body, bearing object, bearing condition and bearing capacity index. Based on this, four factors of waterway bearing capacity were discussed and defined as: within a certain period of time, within a certain river section, the waterway bearing capacity of social and economic sustainable development at a certain scale. The balance index of supply and demand of waterway bearing capacity was proposed as bearing capacity index to evaluate the waterway bearing capacity, that is, the ratio of economy-driven shipping demand to waterway transit capacity. Taking the waterway of the upper Yangtze River as an example, the bearing capacities of three reaches named Yibin-Chongqing, Chongqing-Fuling and Fuling-Yichang were estimated and evaluated, which showed that the bearing capacity of the upper Yangtze River was currently approaching saturation, and the waterway upgrading was urgently needed to meet the sustainable social and economic development in the future. The maximum exploitable water scale was estimated, which indicated that there was a certain improvement potential in the waterway. The case study of the upper reaches of the Yangtze River shows that the proposed connotation and evaluation method of the waterway bearing capacity have a certain applicability, which can provide supports for the planning and construction of the waterway.

Key words: waterway engineering, waterway bearing capacity, waterway scale, evaluation, upper Yangtze River

摘要： 承载力是社会经济发展规划的重要依据，但航道承载力的内涵尚不明确，缺乏对航道承载力的评价研究。分析各类承载力的定义表明其内涵包含承载体、承载对象、承载条件、承载能力指标4个要素，据此探讨明确了航道承载力的4个要素，将航道承载力定义为：在一定时期内、一定河段内，航道在某个尺度下承载社会经济可持续发展的能力。提出航道承载力供需平衡指数作为评价航道承载力的承载能力指标，即经济驱动的航运需求与航道的通过能力之比。以长江上游航道为例，评价宜宾—重庆、重庆—涪陵、涪陵—宜昌三段的航道承载力当前已接近饱和，急需提升航道等级以满足未来的社会经济可持续发展；估算了其航道可开发的最大尺度，表明目前航道还具有一定提升潜力。长江上游航道的实例研究表明，所提出的航道承载力内涵和评价方法具有一定的适用性，可为航道规划建设提供一定的支撑。

关键词: 航道工程 , 航道承载力, 航道尺度, 评价, 长江上游