人民黄河
人民黃河
인민황하
Yellow River
2014年
5期
102-104,107
,共4页
刘晓民%陈艳梅%牟献友%张志澍
劉曉民%陳豔梅%牟獻友%張誌澍
류효민%진염매%모헌우%장지주
环翼式桥墩%试验研究%挡板位置%流速分布
環翼式橋墩%試驗研究%擋闆位置%流速分佈
배익식교돈%시험연구%당판위치%류속분포
ring-wing pier%experimental research%baffle position%velocity distribution
为分析环翼式桥墩周围水流流速分布特征,根据桥墩局部冲刷机理,进行了三种流量、三种水深、三种挡板位置的模型试验。试验结果表明:桥墩周围的表层纵向流速、表层横向流速仅仅受到水流波动的影响。挡板与河床的距离越小,桥墩中心线上的近底纵向流速越大,中心线上及墩侧一定范围的近底横向流速越大,但是近底垂向流速却越小。当挡板距离河床底部为0.3倍水深时,靠近河床边壁处各向流速受挡板影响不大,但是靠近桥墩中心处各向流速在挡板所在位置都有尖点,同时,靠近桥墩中心处的纵向相对紊动强度在测点高度与水深比值为0.4处有极大值。
為分析環翼式橋墩週圍水流流速分佈特徵,根據橋墩跼部遲刷機理,進行瞭三種流量、三種水深、三種擋闆位置的模型試驗。試驗結果錶明:橋墩週圍的錶層縱嚮流速、錶層橫嚮流速僅僅受到水流波動的影響。擋闆與河床的距離越小,橋墩中心線上的近底縱嚮流速越大,中心線上及墩側一定範圍的近底橫嚮流速越大,但是近底垂嚮流速卻越小。噹擋闆距離河床底部為0.3倍水深時,靠近河床邊壁處各嚮流速受擋闆影響不大,但是靠近橋墩中心處各嚮流速在擋闆所在位置都有尖點,同時,靠近橋墩中心處的縱嚮相對紊動彊度在測點高度與水深比值為0.4處有極大值。
위분석배익식교돈주위수류류속분포특정,근거교돈국부충쇄궤리,진행료삼충류량、삼충수심、삼충당판위치적모형시험。시험결과표명:교돈주위적표층종향류속、표층횡향류속부부수도수류파동적영향。당판여하상적거리월소,교돈중심선상적근저종향류속월대,중심선상급돈측일정범위적근저횡향류속월대,단시근저수향류속각월소。당당판거리하상저부위0.3배수심시,고근하상변벽처각향류속수당판영향불대,단시고근교돈중심처각향류속재당판소재위치도유첨점,동시,고근교돈중심처적종향상대문동강도재측점고도여수심비치위0.4처유겁대치。
A lot of experiments were carried out to analyze velocity distribution characteristics around the ring-wing pier. The experiments were de-signed for three kinds of flow velocities,three kinds of water depths,three kinds of baffle locations. The mechanism of local scour around bridge piers was its basis. The experimental results show that the surface’s lengthways velocity and surface’s crosswise velocity are only affected by fluctuation of flow. With the decrease of distance in the baffle and the bed,the bottom’s lengthways velocity and bottom’s crosswise velocity were greater and grea-ter,while the bottom’s vertical velocity was opposite. When the distance between baffle and riverbed is about 0. 3 times of water depth,near the river bed wall there had a little influence and near the bridge pier center there had sharp points in the position of baffle. Meanwhile,near the bridge center there had the maximum value on lengthways turbulence intensity when the ratio of height and depth of the measuring point is 0. 4.