本文選題：箱梁空間效應(yīng)　切入點(diǎn)：腹板斜裂縫　出處：《哈爾濱工業(yè)大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：經(jīng)過近幾十年大規(guī)模的基礎(chǔ)設(shè)施建設(shè),PC連續(xù)箱梁橋因?yàn)榫邆洫?dú)特的優(yōu)勢(shì)已經(jīng)被廣泛采用。隨著經(jīng)濟(jì)發(fā)展、使用功能要求的提高,大跨徑寬箱梁橋也越來越多。但是,從工程實(shí)踐中發(fā)生的一些問題來看,箱梁腹板上出現(xiàn)了普遍開裂的現(xiàn)象,其中尤其是腹板斜裂縫比較常見,甚至達(dá)到腹板裂縫數(shù)量的95%,斜裂縫的存在對(duì)橋梁的安全性和耐久性是十分不利的。鑒于該類病害的普遍性,本文分別從箱梁橋的空間效應(yīng)、當(dāng)前的設(shè)計(jì)計(jì)算方法、預(yù)應(yīng)力鋼筋配筋以及施工工藝等角度對(duì)多腹板寬箱梁的腹板斜裂縫的病害成因、開裂機(jī)理進(jìn)行了研究,并從控制主拉應(yīng)力的角度給出了配筋建議。首先,本文對(duì)腹板斜裂縫病害的相關(guān)文獻(xiàn)進(jìn)行了統(tǒng)計(jì)研究,明確了斜裂縫的性質(zhì),闡述了剪切破壞的機(jī)理。多腹板寬箱梁橋具有顯著地空間效應(yīng),常用的簡化分析方法和針對(duì)簡單橋梁的現(xiàn)行規(guī)范并不能完全反映箱梁的空間效應(yīng),這是引起箱梁腹板開裂的重要原因之一;對(duì)預(yù)應(yīng)力損失估計(jì)不足、下彎束設(shè)計(jì)不合理、施工組織管理不善、未能夠按照設(shè)計(jì)要求嚴(yán)格施工等,導(dǎo)致預(yù)應(yīng)力難以起到限制主拉應(yīng)力的作用引起腹板開裂。其次,本文分別研究了箱梁空間效應(yīng)以及腹板剪應(yīng)力的解析分析方法,通過實(shí)例分析明確了箱梁腹板的受力規(guī)律。依托遼陽河?xùn)|新城宏偉大橋,運(yùn)用MIDAS/FEA有限元分析方法分別從施工階段和成橋階段進(jìn)行了斜截面空間應(yīng)力的精細(xì)化分析,并分別與施工監(jiān)控?cái)?shù)據(jù)和梁單元計(jì)算結(jié)果進(jìn)行了對(duì)比;實(shí)體單元計(jì)算結(jié)果表明在L/4跨及邊跨支點(diǎn)附近是主拉應(yīng)力較大的位置,與實(shí)際PC箱梁橋腹板產(chǎn)生斜裂縫的位置基本一致。加之現(xiàn)行規(guī)范中對(duì)腹板的剪力分配并未明確說明,導(dǎo)致腹板主拉應(yīng)力計(jì)算不準(zhǔn)確,同樣給設(shè)計(jì)帶來了安全隱患。最后,本文在對(duì)多腹板寬箱梁橋斜截面空間應(yīng)力把握的基礎(chǔ)上,對(duì)現(xiàn)有的預(yù)應(yīng)力配筋方法進(jìn)行了研究和評(píng)價(jià)。分別研究了豎向和縱向預(yù)應(yīng)力筋對(duì)腹板受力的影響因素,并從控制主拉應(yīng)力的角度出發(fā),對(duì)豎向筋的配筋間距及施工方法以及縱向預(yù)應(yīng)力筋的設(shè)置形式分別給出了相關(guān)建議。
[Abstract]:PC continuous box girder bridges have been widely used in recent decades because of their unique advantages. With the development of economy and the improvement of function requirements, there are more and more long span and wide box girder bridges. From the point of view of some problems in engineering practice, there is a general cracking on the web of box girder, especially the inclined crack of web. Even reaching 95% of the number of web cracks, the existence of oblique cracks is very unfavorable to the safety and durability of the bridge. In view of the universality of this kind of disease, this paper analyzes the spatial effects of box girder bridges and the current design and calculation methods. In this paper, the causes and mechanism of the diagonal cracks of web plate of multi-web wide box girder are studied from the angles of reinforcement and construction technology, and suggestions are given from the angle of controlling the main tensile stress. This paper makes a statistical study on the diseases of web slant cracks, clarifies the properties of oblique cracks, and expounds the mechanism of shear failure. The commonly used simplified analysis method and the current code for simple bridges can not completely reflect the spatial effect of box girder, which is one of the important reasons for the cracking of box girder web. The construction organization is not well managed and can not be strictly constructed in accordance with the design requirements, which leads to the failure of the prestress to limit the main tensile stress and the cracking of the web plate. In this paper, the spatial effect of box girder and the analytical analysis method of web shear stress are studied respectively, and the force law of box girder web is clarified by examples. The MIDAS/FEA finite element analysis method is used to analyze the spatial stress of the inclined section from the construction stage and the bridge stage respectively, and the results are compared with the construction monitoring data and the calculation results of the beam element. The results of solid element calculation show that the main tensile stress is high near the fulcrum of L / 4 span and side span, which is basically consistent with the actual position of inclined cracks in the web of PC box girder bridge. In addition, the shear distribution of web plate is not clearly stated in the current code. As a result, the calculation of the main tension stress of the web is not accurate, and it also brings the hidden danger of safety to the design. Finally, based on the grasp of the spatial stress of the inclined section of the multi-web wide box girder bridge, The existing prestressed reinforcement methods are studied and evaluated. The influence factors of vertical and longitudinal prestressed tendons on web stress are studied, and the main tension stress is controlled from the point of view of controlling the main tensile stress. The relative suggestions on the spacing and construction methods of vertical tendons and the setting form of longitudinal prestressed tendons are given respectively.
【學(xué)位授予單位】：哈爾濱工業(yè)大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：U448.213

【參考文獻(xiàn)】

相關(guān)期刊論文 前7條

1 曾慶響;韓大建;;預(yù)應(yīng)力混凝土箱梁橋的裂縫防治研究現(xiàn)狀[J];工程力學(xué);2010年S1期

2 王國亮;謝峻;傅宇方;;在用大跨度預(yù)應(yīng)力混凝土箱梁橋裂縫調(diào)查研究[J];公路交通科技;2008年08期

3 袁明;顏東煌;;PC箱梁豎向預(yù)應(yīng)力張拉錨固階段應(yīng)力損失研究[J];公路交通科技;2010年10期

4 陳雙全;;恒載零彎矩理論在克服梁橋梁體開裂下?lián)现械膽?yīng)用[J];公路;2013年01期

5 徐棟;孫遠(yuǎn);吳佳璞;;箱梁薄壁效應(yīng)及腹板開裂成因分析[J];橋梁建設(shè);2009年04期

6 李新勇;張亮亮;朱正剛;;預(yù)應(yīng)力混凝土連續(xù)箱梁橋裂縫成因及防治措施[J];四川建筑;2006年03期

7 呂志濤;潘鉆峰;;大跨徑預(yù)應(yīng)力混凝土箱梁橋設(shè)計(jì)中的幾個(gè)問題[J];土木工程學(xué)報(bào);2010年01期

相關(guān)碩士學(xué)位論文 前2條

1 張映高;多室薄壁箱梁腹板剪力分配規(guī)律初探[D];南京林業(yè)大學(xué);2006年

2 楊剛;大跨徑PC連續(xù)剛構(gòu)橋的空間受力分析[D];長安大學(xué);2014年

，

本文編號(hào)：1649139