橋墩防撞設計中對駁船隊撞墩的分析和處理

摘 要：駁船隊比較寬、比較長，再加上操縱不靈便，在橋梁設計開始階段，對橋型、通航寬度和撞上概率等三方面對它及早考慮是應該的。但是，由于駁船的使用日漸減少，駁船隊一撞就散，撞擊力比較小，因此駁船隊的撞擊力不成為撞塌橋墩的控制因素。本文從駁船隊連接特點出發，求出兩邊駁船對被撞駁船的附加力；并從沖擊動力學的理論出發，計算出后面駁船對被撞駁船壓力峰值與第一撞擊力峰值的時間差，說明疊加之后遠小于該航道上相當載重量的單船的撞擊力。所以，計算航行船舶對橋墩的撞擊力時，主要應該考慮單體船。因此也對我國公路橋梁設計規范源出于駁船隊的規定和美國各州公路和運輸工作者協會（AASHTO）的指南中關于駁船隊的研究，進行了討論。

關鍵詞：駁船隊；駁船撞墩；通航寬度；峰值的時間差；邊駁的附加力

Analysis and Countermeasures for Barge Fleet Collision with Pier during Design of Bridge Anti-collision

CHEN Guoyu

( Shanghai Marine Steel Structure Research Institute， Shanghai 201204 )

Abstract: A barge fleet has big length and breadth and it is not easy to operate because of the mono-hull ship and so at the beginning of bridge design stage， the designer would consider these three factors including bridge type， navigable width and probability of the ship collision with pier. However， there are less and less barges and the barge fleet may disperse immediately after collision with bridge happens， because collision force is small and the collision force would not be the control factor in the ship collision with bridge pier.This paper discusses the peculiarity of the link between the barges in the fleet and the append force from the two close barge and the interval time between two peak values of force are calculated. And when the two peak values of force are piled up the result is far smaller than the peak value of the mono-hull ship. So， when we calculate the force of the collision we should consider the mono-hull ship.This paper also discusses the guides about the barge collision with bridge of China and AASHTO.

Key words: Barge fleet; Barge collision with the bridge; Navigable width; Interval time between two peak values; Appends force from two close barges

1 駁船隊的現狀

大型駁船隊，我國主要在武漢以下的長江中下游從事載貨運輸，曾每年為馬鞍山鋼鐵公司、武漢鋼鐵公司運輸礦石1 000萬t以上（上水），為沿江各電廠運輸煤炭2 000萬t（上、下水）。另外，駁船隊為下游的建筑工地運送砂石也是非常經濟的。

1×4413 kW（6000hp）+20×2 000 t的駁船隊為載重最大的駁船隊之一，如圖1所示，其載重量達到4萬t。

在河流下游的水網地區，流速比長江低些，往往幾百馬力的拖船就可以拉幾千噸的貨，運輸成本比較低。可以看見一字長蛇形的拖駁船隊。如圖2所示。

駁船隊這種運輸方式大約風行了幾十年。“進入21世紀，船運公司增多，貨源分散；……