大跨PC矮塔斜拉橋箱梁應(yīng)力及索梁錨固局部應(yīng)力分析
發(fā)布時(shí)間：2019-03-11 16:50
【摘要】：矮塔斜拉橋因其外形美觀、主梁剛度大、跨越能力強(qiáng)可用于鐵路橋梁的建設(shè)。本文是以即將建設(shè)的成昆鐵路擴(kuò)能改造工程三堆子金沙江預(yù)應(yīng)力混凝土矮塔斜拉橋?yàn)楸尘埃瑢?duì)預(yù)應(yīng)力混凝土矮塔斜拉橋的若干關(guān)鍵問(wèn)題進(jìn)行了數(shù)值模擬分析，主要工作和結(jié)論如下： 1.基于APDL語(yǔ)言對(duì)矮塔斜拉橋的索力優(yōu)化進(jìn)行參數(shù)化分析。斜拉索是矮塔斜拉橋的重要組成部分，斜拉索與主梁的錨固使主梁類似多點(diǎn)彈性支撐的連續(xù)梁。當(dāng)荷載確定時(shí)，通過(guò)調(diào)整斜拉索的索力，可以改變結(jié)構(gòu)的受力分配，使反映結(jié)構(gòu)的各種性能指標(biāo)達(dá)到最優(yōu)。矮塔斜拉橋?yàn)槿S空間結(jié)構(gòu)，要進(jìn)行索力優(yōu)化計(jì)算需要建立空間有限元分析模型，本文選用彎曲能量最小的原理，通過(guò)ANSYS參數(shù)化設(shè)計(jì)語(yǔ)言APDL編制索力優(yōu)化程序段，對(duì)索力優(yōu)化進(jìn)行了分析計(jì)算，得到成橋狀態(tài)恒載作用下的一組索力值。本文建立的索力優(yōu)化模型精確模擬了主梁截面在高度和寬度方向的變化，彌補(bǔ)了以往應(yīng)用ANSYS建模時(shí)模擬主梁的不足。計(jì)算實(shí)踐表明，所編制程序計(jì)算精度較高，應(yīng)用方便，并且收斂速度快，具有很高的應(yīng)用價(jià)值。 2.采用ANSYS12.1建立預(yù)應(yīng)力混凝土矮塔斜拉橋上部結(jié)構(gòu)三維空間有限元模型。計(jì)算分析表明，結(jié)構(gòu)在自重、二期恒載和預(yù)應(yīng)力共同作用下主梁的線型平順，主梁受力均勻，各截面處于受壓狀態(tài)，出現(xiàn)的最大壓應(yīng)力遠(yuǎn)小于混凝土的抗壓強(qiáng)度限值。結(jié)構(gòu)在自重、二期恒載、預(yù)應(yīng)力和最不利活載共同作用下主梁各控制截面的豎向位移和縱向應(yīng)力均在合理范圍內(nèi)。在活載（偏載）作用下，得到了主梁各控制截面左、中、右腹板的縱向應(yīng)力分布特征。結(jié)果表明在主梁向下?lián)锨兓顒×业牟课�，偏載下方邊腹板的縱向應(yīng)力小于遠(yuǎn)離活載的另一邊腹板，可知該部位是主梁受力最不利的區(qū)域，如中跨跨中截面和邊跨跨中截面，而主梁其他部位偏載下方邊腹板的縱向應(yīng)力大于遠(yuǎn)離活載的另一邊腹板，由于主梁全截面受壓，出現(xiàn)這樣的應(yīng)力分配使結(jié)構(gòu)具有一定的安全儲(chǔ)備。本文首次探索了預(yù)應(yīng)力混凝土矮塔斜拉橋單箱雙室主梁左、中、右三個(gè)腹板的縱向應(yīng)力分布特征，得到了較好的結(jié)果，可為同類型的橋梁設(shè)計(jì)提供參考。 3.運(yùn)用ANSYS12.1對(duì)多種新型的索梁錨固方式進(jìn)行了數(shù)值分析。結(jié)果表明：在單鋼板錨拉的情況下，雖然錨固段主梁混凝土絕大部分區(qū)域的應(yīng)力值在允許的范圍內(nèi)，但是鋼板局部應(yīng)力過(guò)大，通過(guò)分析不宜采取該錨拉方式。采用雙鋼板錨拉時(shí)，錨固段主梁混凝土和鋼錨拉板結(jié)構(gòu)絕大部分區(qū)域應(yīng)力在允許的范圍內(nèi)，局部應(yīng)力較大的部位可以采取適當(dāng)?shù)募庸檀胧�，可以滿足結(jié)構(gòu)受力要求�？傮w來(lái)說(shuō)采用鋼錨拉板錨固，結(jié)構(gòu)新穎，樣式優(yōu)美，但是錨拉結(jié)構(gòu)傳力復(fù)雜，鋼板和混凝土之間的連接不好處理，要消耗大量鋼材，費(fèi)用較高。當(dāng)采用混凝土錨拉塊錨固時(shí)，必須適當(dāng)加入預(yù)應(yīng)力才能滿足結(jié)構(gòu)受力要求。通過(guò)圓導(dǎo)角錨塊錨固和楔形導(dǎo)角錨固的數(shù)值計(jì)算，可知采用楔形導(dǎo)角錨塊錨固時(shí)，，錨固段梁體和錨拉塊大部分處于受壓狀態(tài)，個(gè)別區(qū)域出現(xiàn)拉應(yīng)力，與圓導(dǎo)角錨塊錨固時(shí)的最大拉應(yīng)力值相比，出現(xiàn)的最大拉應(yīng)力要小的多，并且應(yīng)力集中的面積很小。楔形導(dǎo)角大部分處于受壓狀態(tài)，其中出現(xiàn)最大拉應(yīng)力的位置屬于構(gòu)造發(fā)生突變的截面，出現(xiàn)局部應(yīng)力集中現(xiàn)象，集中應(yīng)力數(shù)值小，范圍小，如果采用圓角過(guò)渡，可以滿足結(jié)構(gòu)受力要求。索梁錨固的方式不同，錨固區(qū)梁段的受力比較復(fù)雜，影響因素較多，通過(guò)對(duì)四種不同錨固型式的分析計(jì)算，可為矮塔斜拉橋的索梁錨固設(shè)計(jì)提供參考。
[Abstract]:The short tower cable-stayed bridge can be used for the construction of the railway bridge because of its beautiful appearance, large rigidity of the main beam and strong crossing ability. In this paper, a numerical simulation analysis of several key problems of the pre-stressed concrete short tower cable-stayed bridge is carried out based on the construction of the pre-stressed concrete low-tower cable-stayed bridge of the Sanhe Jinshajiang pre-stressed concrete cable-stayed bridge. The main work and conclusion are as follows: 1. The optimization of the cable force of the short tower cable-stayed bridge based on the APDL language Analysis. The stay cable is an important part of the short tower cable-stayed bridge. The anchor of the stay cable and the main beam causes the main girder to be similar to the multi-point elastic support. When the load is determined, the stress distribution of the structure can be changed by adjusting the cable force of the stay cable, so that the various performance indexes of the reflecting structure can reach the most For the three-dimensional space structure, the low-tower cable-stayed bridge is a three-dimensional space structure. It is necessary to establish a space finite element analysis model for the optimization of the cable force. In this paper, the principle of the minimum bending energy is selected, and the cable force optimization program segment is prepared by the ANSYS parametric design language APDL, and the optimization of the cable force is analyzed. calculation to obtain a set of cable force under the constant load of the bridge state The cable force optimization model established in this paper accurately simulates the variation of the cross section of the main beam in the height and width direction, and makes up the problem that the main girder is not simulated when the ANSYS is used for modeling. The calculation practice shows that the program has high calculation accuracy, convenient application and high convergence rate, and has a very high application price. Value.2. Use ANSYS2.1 to set up the three-dimensional space of the upper structure of the prestressed concrete short tower cable-stayed bridge The calculation results show that the structure is smooth and the main beam is smooth and the main beam is uniform under the common action of the dead weight, the second phase and the pre-stress, and the stress of the main beam is uniform. The maximum compressive stress of the main beam is much smaller than that of the concrete. The vertical displacement and longitudinal stress of each control section of the main beam under the common action of the dead weight, the second phase, the prestress and the most unfavorable live load are both reasonable and reasonable. The longitudinal stress of the left, middle and right webs of each control section of the main beam is obtained under the action of live load (partial load). The results show that the longitudinal stress of the web under the partial load is less than that of the other side of the live load on the most severe part of the downward deflection of the main beam. It can be seen that this part is the most unfavorable area of the main beam, as shown in the cross-section and the cross-span of the cross-span. The longitudinal stress of the web under the partial load of the other parts of the main beam is greater than the other side of the web which is far from the live load, and due to the compression of the whole section of the main beam, such stress distribution will make the structure have a certain safety. The longitudinal stress distribution in the left, middle and right three webs of the single-box, double-chamber, double-chamber, double-chamber main girder of the prestressed concrete short-tower cable-stayed bridge is studied for the first time in this paper, and the better results can be obtained, which can be provided for the same type of bridge design. For information.3. Use the ANSYS2.1 to anchor a variety of new cable-beam anchoring methods The numerical analysis is carried out. The results show that, in the case of single steel plate anchor drawing, although the stress value of most area of the main beam of the anchor section is within the allowable range, the local stress of the steel plate is too large, and it is not appropriate to adopt the analysis. In the anchor pulling mode, when the double-steel plate anchor is adopted, most of the area stress of the main beam concrete and the steel-anchor pulling plate structure of the anchor section is within the allowable range, and the part with the larger local stress can adopt appropriate reinforcement measures, so that the knot can be met. The structure is required. In general, the steel anchor pulling plate is adopted for anchoring, the structure is novel and the style is beautiful, but the force transmission of the anchor pulling structure is complex, the connection between the steel plate and the concrete is not good, and a large amount of steel is to be consumed. The cost is high. When the concrete anchor block is used for anchoring, the pre-stress must be properly added to meet the knot. According to the numerical calculation of the anchorage of the anchor block and the wedge-shaped guide angle of the round guide angle anchor block, it can be seen that when the wedge-shaped guide angle anchor block is used for anchoring, most of the anchor section beam body and the anchor block are in the pressed state, the tensile stress in the individual area, and the maximum pull when the anchor block is anchored by the round guide angle anchor block. the maximum tensile stress that occurs when compared to the stress value is small and the stress concentration The area of the wedge-shaped guide angle is very small. The wedge-shaped guide angle is mostly in the pressed state, the position where the maximum tensile stress occurs belongs to the section with the abrupt change of the structure, the local stress concentration phenomenon occurs, the concentrated stress value is small, the range is small, and if the fillet transition is adopted, the junction can be met. The structure and force requirements are different. The anchorage mode of the cable beam is different, the stress of the beam section of the anchorage zone is more complex and the influence factor is more. Through the analysis and calculation of the four different anchoring types, the cable beam anchorage for the short tower cable-stayed bridge can be provided.
【學(xué)位授予單位】：蘭州交通大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類號(hào)】：U448.27;U441
本文編號(hào)：2438444
[Abstract]:The short tower cable-stayed bridge can be used for the construction of the railway bridge because of its beautiful appearance, large rigidity of the main beam and strong crossing ability. In this paper, a numerical simulation analysis of several key problems of the pre-stressed concrete short tower cable-stayed bridge is carried out based on the construction of the pre-stressed concrete low-tower cable-stayed bridge of the Sanhe Jinshajiang pre-stressed concrete cable-stayed bridge. The main work and conclusion are as follows: 1. The optimization of the cable force of the short tower cable-stayed bridge based on the APDL language Analysis. The stay cable is an important part of the short tower cable-stayed bridge. The anchor of the stay cable and the main beam causes the main girder to be similar to the multi-point elastic support. When the load is determined, the stress distribution of the structure can be changed by adjusting the cable force of the stay cable, so that the various performance indexes of the reflecting structure can reach the most For the three-dimensional space structure, the low-tower cable-stayed bridge is a three-dimensional space structure. It is necessary to establish a space finite element analysis model for the optimization of the cable force. In this paper, the principle of the minimum bending energy is selected, and the cable force optimization program segment is prepared by the ANSYS parametric design language APDL, and the optimization of the cable force is analyzed. calculation to obtain a set of cable force under the constant load of the bridge state The cable force optimization model established in this paper accurately simulates the variation of the cross section of the main beam in the height and width direction, and makes up the problem that the main girder is not simulated when the ANSYS is used for modeling. The calculation practice shows that the program has high calculation accuracy, convenient application and high convergence rate, and has a very high application price. Value.2. Use ANSYS2.1 to set up the three-dimensional space of the upper structure of the prestressed concrete short tower cable-stayed bridge The calculation results show that the structure is smooth and the main beam is smooth and the main beam is uniform under the common action of the dead weight, the second phase and the pre-stress, and the stress of the main beam is uniform. The maximum compressive stress of the main beam is much smaller than that of the concrete. The vertical displacement and longitudinal stress of each control section of the main beam under the common action of the dead weight, the second phase, the prestress and the most unfavorable live load are both reasonable and reasonable. The longitudinal stress of the left, middle and right webs of each control section of the main beam is obtained under the action of live load (partial load). The results show that the longitudinal stress of the web under the partial load is less than that of the other side of the live load on the most severe part of the downward deflection of the main beam. It can be seen that this part is the most unfavorable area of the main beam, as shown in the cross-section and the cross-span of the cross-span. The longitudinal stress of the web under the partial load of the other parts of the main beam is greater than the other side of the web which is far from the live load, and due to the compression of the whole section of the main beam, such stress distribution will make the structure have a certain safety. The longitudinal stress distribution in the left, middle and right three webs of the single-box, double-chamber, double-chamber, double-chamber main girder of the prestressed concrete short-tower cable-stayed bridge is studied for the first time in this paper, and the better results can be obtained, which can be provided for the same type of bridge design. For information.3. Use the ANSYS2.1 to anchor a variety of new cable-beam anchoring methods The numerical analysis is carried out. The results show that, in the case of single steel plate anchor drawing, although the stress value of most area of the main beam of the anchor section is within the allowable range, the local stress of the steel plate is too large, and it is not appropriate to adopt the analysis. In the anchor pulling mode, when the double-steel plate anchor is adopted, most of the area stress of the main beam concrete and the steel-anchor pulling plate structure of the anchor section is within the allowable range, and the part with the larger local stress can adopt appropriate reinforcement measures, so that the knot can be met. The structure is required. In general, the steel anchor pulling plate is adopted for anchoring, the structure is novel and the style is beautiful, but the force transmission of the anchor pulling structure is complex, the connection between the steel plate and the concrete is not good, and a large amount of steel is to be consumed. The cost is high. When the concrete anchor block is used for anchoring, the pre-stress must be properly added to meet the knot. According to the numerical calculation of the anchorage of the anchor block and the wedge-shaped guide angle of the round guide angle anchor block, it can be seen that when the wedge-shaped guide angle anchor block is used for anchoring, most of the anchor section beam body and the anchor block are in the pressed state, the tensile stress in the individual area, and the maximum pull when the anchor block is anchored by the round guide angle anchor block. the maximum tensile stress that occurs when compared to the stress value is small and the stress concentration The area of the wedge-shaped guide angle is very small. The wedge-shaped guide angle is mostly in the pressed state, the position where the maximum tensile stress occurs belongs to the section with the abrupt change of the structure, the local stress concentration phenomenon occurs, the concentrated stress value is small, the range is small, and if the fillet transition is adopted, the junction can be met. The structure and force requirements are different. The anchorage mode of the cable beam is different, the stress of the beam section of the anchorage zone is more complex and the influence factor is more. Through the analysis and calculation of the four different anchoring types, the cable beam anchorage for the short tower cable-stayed bridge can be provided.
【學(xué)位授予單位】：蘭州交通大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類號(hào)】：U448.27;U441
【參考文獻(xiàn)】
相關(guān)期刊論文 前1條
1 潘慧敏;李小珍;司秀勇;;某斜拉橋索梁錨固結(jié)構(gòu)有限元分析[J];四川建筑;2006年01期
相關(guān)博士學(xué)位論文 前1條
1 陶齊宇;大跨度斜拉橋預(yù)應(yīng)力混凝土索塔關(guān)鍵問(wèn)題研究[D];西南交通大學(xué);2012年
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