繁忙船闸的船舶待闸时间分析与估算

Estimation and analysis on delays at busy waterway lock

为了反映内河船闸的服务质量,并为船闸工程的经济评价提供基础数据,以目前国内仅有的京杭运河施桥船闸多年运行实测资料为例,统计分析了繁忙船闸的船舶待闸时间特点,并基于G/G/1排队模型,建立了估算繁忙船闸船舶待闸时间的近似数学模型.结果表明：该繁忙船闸的船队待闸时间主要分布在16h以内,单机船的待闸时间主要分布在6h以内或者14-22h之间;船舶待闸时间的长短不仅与其交通负荷有关,还与船舶到闸和过闸的离散程度有关;模型能够合理地给出船舶的平均待闸时间,而且船舶待闸时间的理论分布与实测数据吻合程度良好.说明该模型是可靠的,能够用来估算类似繁忙船闸的船舶待闸时间.

Delays at busy waterway locks are a measurement of service quality, and are the basic data for the economic evaluation of lock projects. According to the unique observed data collected at Shiqiao Lock on the Grand Canal, the characteristics of lock delays were analyzed. Based on a G/G/1 queue, an approximate model was developed to estimate delays at busy waterway locks. The results show that tows＇ delays are mainly distributed within 16 h, and boats/ships＇ delays distributed within 6 h or 14 -22 h in Shiqiao Lock. Lock delays are related with not only the traffic load, but also the discrete degree of ships＇ arrival and departure. The verification results show that the estimated average values of lock delays can be given reasonably by this model and the corresponding theoretical distribution accords well with the observed data. It can be concluded that the model is suitable for estimating delays of such normal operating busy locks.