本文關鍵詞： 鐵路預應力混凝土梁 有效預應力 有限元模擬 自振頻率 動力試驗　出處：《石家莊鐵道大學》2014年碩士論文　論文類型：學位論文

【摘要】：京通線48號橋位于懷柔北到小水峪間，中心里程K60+481，為單線橋，1974年建成，橋上直線平坡，孔跨式樣為16孔跨度23.8m預應力混凝土T梁，主梁中心距1.8m，梁高2.1m，跨中腹板厚0.14m，搖軸支座，圓端形混凝土墩，橋高10m左右，該梁采用直徑為5mm的碳素鋼絲構成五種預應力鋼筋N1、N2、N3、N4、N5，共9束沿梁長曲線布置。本文以其中一跨為研究對象，通過理論計算、有限元通用軟件ANSYS進行模擬加上現(xiàn)場實體試驗三種途徑對該梁現(xiàn)存的有效預應力進行計算識別并利用軟件模型探討預應力對梁自振頻率的影響及其之間的關系。主要完成以下工作： (1)用有限元軟件ANSYS建立試驗梁的模型，進行梁的前五階頻率計算，在此基礎上，將預應力鋼筋束整體和分組結合組成多種計算情況分別計算了梁體在不同預應力值的組合下的自振頻率值，模擬計算結果表明，自振頻率隨著預應力的減小而減小，在全預應力、部分預應力和無預應力三種狀態(tài)的界限處的改變值很明顯，，而且，預應力筋所處的位置和所施加的預應力值的大小都會對自振頻率有不同的影響。 (2)對原橋進行動載試驗測得在有效預應力水平下的自振頻率，在實體試驗梁上進行消壓荷載試驗和開槽法試驗對有效預應力值進行檢測，將動載試驗得到的頻率值代入模型計算得到的有效預應力和頻率關系曲線中得到有效預應力值，驗證頻率和有效預應力之間的關系以及利用頻率識別有效預應力值的可行性。 (3)了解試驗梁的基本情況，參照中國、美國、歐洲三種預應力損失的計算方法和公式，按照我國規(guī)定對試驗梁的有效預應力值和頻率進行理論計算。 (4)結合理論、模擬和實體試驗得到的梁體有效預應力值和梁的動力特性值，對本文的有效預應力識別方法進行研究。
[Abstract]:Jingtong Line 48 Bridge is located between Huairou North and Xiaoshuiyu. The center mileage is K60481. it is a single-line bridge. In 1974, the bridge has a straight flat slope with a 16-hole span of 23.8m prestressed concrete T-beam. The center distance of the main beam is 1.8 m, the beam height is 2.1 m, the thickness of the span is 0.14 m, the rocking shaft supports, the round end concrete pier, the bridge height is about 10 m, The beam is composed of five kinds of prestressed steel bar N _ (1) N _ (2) N _ (2) N _ (3) N _ (3) N _ (4) N _ (5) with a diameter of 5 mm. A total of 9 beams are arranged along the beam length curve. In this paper, one span is taken as the research object, and the theoretical calculation is carried out. The finite element general software ANSYS is used to simulate and test the existing effective prestressing force of the beam. The influence of prestress on the natural vibration frequency of beam and the relationship between them are discussed by using the software model. The main tasks are as follows:. 1) using the finite element software ANSYS to establish the model of the test beam, and calculate the first five order frequency of the beam, on the basis of which, The self-vibration frequency of beam under different prestress values is calculated separately by combining the whole and grouping of prestressed bars. The simulation results show that the natural vibration frequency decreases with the decrease of prestress. The change value at the boundary of full prestress, partial prestress and non prestressing is obvious. Moreover, the position of prestressing tendons and the magnitude of prestressing force applied will have different effects on the natural vibration frequency. (2) the natural vibration frequency of the original bridge is measured by dynamic load test under the effective prestressing force level, and the effective prestress value is tested by the static load test on the solid test beam and the slotted test. The frequency value obtained from dynamic load test is substituted into the effective prestressing force and the effective prestress value is obtained in the curve of frequency relation, which verifies the relationship between frequency and effective prestress and the feasibility of identifying the effective prestress value by frequency. (3) to understand the basic situation of the test beam, according to the calculation methods and formulas of three kinds of prestress loss in China, the United States and Europe, the effective prestress value and frequency of the test beam are calculated theoretically according to the regulations of our country. 4) combined with the theory, the effective prestress value of beam and the dynamic characteristic value of beam obtained by simulation and solid test, the identification method of effective prestressing force in this paper is studied.
【學位授予單位】：石家莊鐵道大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：U441.5

【參考文獻】

相關期刊論文 前10條

1 楊國立;李瑞鴿;;預應力混凝土梁中預應力損失檢測方法的發(fā)展與展望[J];四川建筑科學研究;2008年04期

2 林偉民,范秀蘭;預應力總損失的簡化計算方法[J];平頂山工學院學報;2005年01期

3 歐陽華江;鋼筋混凝土梁剛度計算通用公式[J];大連工學院學報;1987年04期

4 丁紅林;;既有鐵路簡支T梁橋的動載試驗研究及有限元分析[J];福建建材;2011年09期

5 趙沖久;馬津渤;王立軍;;在役預應力混凝土結構損傷檢測與評定技術綜述[J];港工技術;2007年03期

6 張耀庭;李宏健;;全預應力砼梁動力性能試驗研究[J];工程力學;2008年S1期

7 郭琦;賀拴海;;大跨度PC橋梁有效預應力衰變行為監(jiān)測與評估模型研究[J];公路交通科技;2011年05期

8 張貴海;;鋼筋混凝土梁剛度計算的簡化模式[J];甘肅科技;2006年04期

9 張耀庭,蔡利建,張長跑,李瑞鴿;梁式預應力混凝土結構檢測方法的研究現(xiàn)狀[J];工業(yè)建筑;2005年11期

10 夏春,李科,金東漢;非破壞鋼筋混凝土結構鋼筋實際應力測定法[J];黑龍江礦業(yè)學院學報;1998年02期

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