本文選題：船舶受力 + 前排樁　； 參考：《長(zhǎng)沙理工大學(xué)》2015年碩士論文

【摘要】：橋梁建設(shè)加強(qiáng)了江河兩岸溝通和交流,促進(jìn)了社會(huì)經(jīng)濟(jì)的發(fā)展。然而一些橋墩布置在通航水域中,繞經(jīng)橋墩水流受邊界影響出現(xiàn)局部流態(tài),對(duì)船舶正常航行產(chǎn)生不利影響,可能妨礙通航并影響橋梁的安全。對(duì)于橋墩周圍水流的研究成果已經(jīng)較為豐富,但是對(duì)橋區(qū)航行船舶的受力問題還缺乏系統(tǒng)的研究。本文從船舶受力的角度分析探討橋區(qū)航道船舶通航安全問題,提出改善船舶航行條件的措施,對(duì)保障橋區(qū)附近水域的通航安全及橋梁本身的安全具有重要意義。采用RNG、k-ε紊流模型對(duì)通航水域的橋墩單墩以及受前排樁保護(hù)橋增的周圍流場(chǎng)進(jìn)行數(shù)值模擬。采用測(cè)力天平測(cè)量?jī)x以及應(yīng)變應(yīng)力采集系統(tǒng),測(cè)量橋墩單墩周圍船舶平面受力狀況,并進(jìn)一步測(cè)量不同前排樁布置工況下橋樁周圍船舶平面受力狀況。通過分析,得出主要結(jié)論如下:1、前排樁的設(shè)置,改善了橋墩局部水流結(jié)構(gòu)和橋墩周圍流場(chǎng)。當(dāng)上游來(lái)流遇到前排樁T,水流受樁的引導(dǎo)產(chǎn)生偏離和分流,前排樁的分流作用將水流分向橋墩兩側(cè),減緩水流對(duì)橋墩的直接作用,降低了墩前雍水,橋墩兩側(cè)水流得到平緩,同T在樁后形成一個(gè)低速尾流區(qū)域。受樁后尾流減速的影響,墩前行進(jìn)水流動(dòng)量減小,橋墩墩前橫流相應(yīng)減小,橋墩周圍通航條件得到改善。2、前排樁改善效果通航條件的作用與前排樁的相關(guān)因素有關(guān),涉及前排樁數(shù)量,前排樁與橋墩間距離等因素有關(guān)。在橋樁距卡相等的工況下,隨著樁數(shù)增加,樁后尾流減速區(qū)域越大,橋墩周圍不安全通航區(qū)域改善越明顯。在樁數(shù)一定的工況下,前排樁尾流減速區(qū)域效果與橋樁距離有關(guān),橋樁距太小,前排樁對(duì)墩前行進(jìn)流速減緩不夠充足;橋樁距太大,前排樁對(duì)墩前行進(jìn)流速減緩效果減弱。3、船體平面受力在船體中心與橋墩中心交會(huì)區(qū)域附近達(dá)到最大,且船體所受橫向力在船舶與橋墩交會(huì)過程中受力方向會(huì)發(fā)生兩次轉(zhuǎn)變。船舶平面受力的變化與水流流速正相關(guān),船舶的平面受力峰值及分布區(qū)域不因水深改變而改變。船舶在橋墩周圍時(shí),船舶所受縱向力和橫向力峰值隨流速增大而增大,且船舶所受橫向吸附力的分布區(qū)間隨著流速增大而向下游發(fā)展4、本文以船舶沿水流橫向受力變化曲線變化率近似為零邊界為橋墩對(duì)船舶受力影響邊界,橋墩到船舶受力影響邊界的距離定義為船舶通航影響寬度。橋墩對(duì)船舶通航影響寬度與流速成正相關(guān),即橋墩對(duì)船舶受力影響寬度隨流速增大而增大。僅本文研究水流條件下,橋墩對(duì)船舶受力的影響寬度不超過2.8倍橋墩墩寬。5.船舶在前排樁區(qū)域附近時(shí),船舶平面受力出現(xiàn)變化,但是總體變化不大。前排樁本身對(duì)船舶受力影響遠(yuǎn)小于橋墩對(duì)船舶受力的影響。前排樁的設(shè)置對(duì)船舶縱向受力突增和橫向吸附力有減小的作用。2倍墩寬橋樁距、三樁數(shù)量工況下,前排樁對(duì)船舶受力改善效果最佳。
[Abstract]:Bridge construction has strengthened communication and exchange between the two sides of the river and promoted social and economic development. However, some piers are arranged in navigable waters, and the local flow around the pier is affected by the boundary, which has adverse effects on the normal navigation of ships, which may hinder navigation and affect the safety of bridges. The research results of the flow around the bridge pier have been rich, but there is no systematic research on the force problem of the navigating ship in the bridge area. In this paper, the problem of navigation safety in waterway in bridge area is analyzed and discussed from the point of view of ship force, and the measures to improve the navigation conditions of ships are put forward, which is of great significance to ensure the navigation safety in the waters near the bridge area and the safety of the bridge itself. RNG k- 蔚 turbulence model is used to numerically simulate the flow field of single pier of bridge piers in navigable waters and the increased flow field of bridge protected by front row piles. Using the force balance measuring instrument and the strain and stress collecting system, the plane stress state of the ship around the single pier of the bridge pier is measured, and the plane stress condition of the ship around the bridge pile under different conditions of the front row pile arrangement is further measured. Through the analysis, the main conclusions are as follows: 1, the arrangement of the front row pile improves the local flow structure of the pier and the flow field around the pier. When the upstream flow meets the front pile T, the flow of water deviates and distributes under the guidance of the pile. The distributary effect of the front row pile divides the water flow to the two sides of the pier, which slows down the direct effect of the water flow on the pier, reduces the uvula in front of the pier, and the flow of water on both sides of the pier is flattened. A low velocity wake region is formed behind the pile with T. Influenced by the deceleration of wake flow after the pile, the influent flow momentum before the pier decreases, the cross flow in front of the pier decreases accordingly, the navigation conditions around the pier are improved by .2.The effect of improving the navigation condition of the front row pile is related to the related factors of the front row pile. The number of front piles and the distance between front piles and piers are related. With the increase of pile number, the larger the deceleration area of wake flow behind the pile is, the more obvious the improvement of unsafe navigation area around the pier is. Under certain working conditions, the effect of wake deceleration zone of front row pile is related to the distance of bridge pile, the distance of bridge pile is too small, the velocity of moving velocity of front row pile is not enough, the distance of bridge pile is too large, The deceleration effect of the front row pile on the velocity of moving forward of the pier is weakened. 3. The plane force of the hull reaches the maximum near the intersection area between the hull center and the pier, and the transverse force of the hull changes twice during the course of the intersection between the ship and the pier. The variation of ship plane force is positively related to the flow velocity, and the peak value and distribution area of ship plane force are not changed by the change of water depth. When the ship is around the pier, the peak value of the longitudinal and transverse forces on the ship increases with the increase of the velocity. With the increase of the velocity of the ship, the distribution range of the transverse adsorption force on the ship develops downstream. In this paper, the change rate of the lateral force curve of the ship along the water flow is approximately zero boundary as the influence boundary of the bridge pier on the ship force. The distance from the pier to the force-bearing boundary of the ship is defined as the width of the ship's navigable influence. The influence width of piers on ship navigation is positively related to the velocity of the ship, that is, the influence width of the pier on the ship increases with the increase of the velocity. Only in this paper, under the condition of water flow, the influence of bridge piers on ship force is not more than 2.8 times the width of piers. When the ship is near the front row pile area, the plane force of the ship changes, but the overall change is not significant. The influence of front pile itself on ship force is much smaller than that of bridge pier. The installation of the front row pile has the function of decreasing the longitudinal force and the lateral adsorption force of the ship. 2 times the pile distance of the wide bridge with piers. Under the working conditions of three piles, the effect of the front row pile on the ship's force improvement is the best.
【學(xué)位授予單位】：長(zhǎng)沙理工大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：U442.3

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 胡旭躍;祖小勇;程永舟;李銀發(fā);王巧洋;;圓端形橋墩側(cè)向紊流寬度的試驗(yàn)研究[J];水利水運(yùn)工程學(xué)報(bào);2009年03期

2 李鶴高;林鋼;;橋墩周圍紊流區(qū)寬度研究[J];水運(yùn)工程;2009年08期

3 莊元;劉祖源;;橋墩紊流寬度的試驗(yàn)研究[J];武漢理工大學(xué)學(xué)報(bào)(交通科學(xué)與工程版);2007年05期

4 姚熊亮;方媛媛;戴紹仕;王領(lǐng);;基于LES方法圓柱繞流三維數(shù)值模擬[J];水動(dòng)力學(xué)研究與進(jìn)展A輯;2007年05期

5 孫東坡;楊慧麗;張曉松;王二平;;橋墩沖刷坑的三維流場(chǎng)測(cè)量與數(shù)值模擬[J];水科學(xué)進(jìn)展;2007年05期

6 房世龍;陳紅;王崗;;橋墩局部沖刷防護(hù)工程特性研究綜述[J];水利水電科技進(jìn)展;2007年04期

7 M. Anisul HAQUE;Md. Munsur RAHMAN;G.M. Tarekul ISLAM;M. Asad HUSSAIN;;SCOUR MITIGATION AT BRIDGE PIERS USING SACRIFICIAL PILES[J];International Journal of Sediment Research;2007年01期

8 何小花;陳立;王鑫;張炯;;橋墩紊流寬度的試驗(yàn)研究[J];水利水運(yùn)工程學(xué)報(bào);2006年03期

9 胡旭躍,陳健強(qiáng),許足懷,胡越高;耒水公路大橋礙航問題整治方法探討[J];水運(yùn)工程;2003年06期

10 陳慶光,徐忠,張永建;RNG κ-ε模式在工程湍流數(shù)值計(jì)算中的應(yīng)用[J];力學(xué)季刊;2003年01期

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