柔性系桿拱橋系桿力損失與系桿更換技術(shù)研究
發(fā)布時間：2018-08-20 10:22
【摘要】：本文以某跨徑布置為46m+202m+46m的柔性系桿鋼管混凝土拱橋為工程背景,以系桿拱橋可靠度理論及有限元分析理論為基礎(chǔ),針對不同系桿力損失情況下全橋力學性能變化、橋梁可靠度變化及系桿更換方法進行了深入研究。主要研究工作包括:①針對依托工程,采用一次二階矩法及PNET法,研究了系桿力損失分別為0%、5%、10%、15%、20%及25%六種工況及不同使用年限下全橋力學性能及橋梁可靠度的變化規(guī)律。結(jié)果表明:各工況下,各構(gòu)件可靠度表現(xiàn)為主拱肋邊拱樁基;全橋最薄弱的部位出現(xiàn)在樁底截面。當系桿力損失為15%時,體系安全等級在任何使用年限內(nèi)均小于三級,為保證橋梁的最低安全等級,當系桿力損失超過15%后應盡快實施系桿更換。②針對依托工程,以系桿力損失10%為初始狀態(tài),提出了4種系桿更換方案:單側(cè)同時更換1根、2根、3根和4根,各方案下均實行上下游側(cè)系桿同時更換,并對不同方案下的車輛進行間斷放行,同時在施工間歇時對車輛進行限重放行。③對比分析了4種方案下橋梁力學行為變化及可靠度變化,結(jié)果表明:各方案下,控制截面應力、橋面撓度及系桿內(nèi)力等均滿足要求;但可靠度分析表明僅方案1、2可行,此外,方案2相比方案1的施工時間可縮短約一半,因此,建議采用方案2進行系桿更換。
[Abstract]:Based on the engineering background of a flexible concrete-filled steel tubular arch bridge with a span of 46m 202m and 46m, and based on the reliability theory and finite element analysis theory of the tied arch bridge, this paper aims at the change of mechanical properties of the whole bridge under the condition of different tie bar force loss. The variation of bridge reliability and the replacement method of tie rod are studied in depth. The main research work includes: 1, the first order second moment method and PNET method are used to study the variation of mechanical properties and bridge reliability of the whole bridge under six different working conditions and different service life respectively, the loss of tie rod force is 0, 5, 10, 15, 15, 20%, and 25%, respectively. The results show that the reliability of each component is the main arch rib arch pile foundation under each working condition, and the weakest part of the whole bridge appears in the pile bottom section. When the loss of tie bar force is 15, the safety grade of the system is less than three levels in any service life. In order to ensure the lowest safety grade of bridge, when the loss of tie bar force exceeds 15%, the replacement of tie rod should be carried out as soon as possible to support the project. Taking 10% loss of tie rod force as the initial state, four kinds of tie-bar replacement schemes are put forward: one side, two branches, three and four, all of which are replaced at the same time, and the vehicles under different schemes are released intermittently. At the same time, the change of mechanical behavior and reliability of the bridge under the four schemes are compared and analyzed during the intermittent construction. The results show that the control section stress, the deflection of bridge deck and the internal force of tie rod meet the requirements under each scheme; However, the reliability analysis shows that only option 1 / 2 is feasible, in addition, the construction time of scheme 2 can be shortened by about half compared with that of scheme 1. Therefore, it is suggested that option 2 be used to replace the tie bar.
【學位授予單位】：重慶交通大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：U445.7;U448.225
本文編號：2193260
[Abstract]:Based on the engineering background of a flexible concrete-filled steel tubular arch bridge with a span of 46m 202m and 46m, and based on the reliability theory and finite element analysis theory of the tied arch bridge, this paper aims at the change of mechanical properties of the whole bridge under the condition of different tie bar force loss. The variation of bridge reliability and the replacement method of tie rod are studied in depth. The main research work includes: 1, the first order second moment method and PNET method are used to study the variation of mechanical properties and bridge reliability of the whole bridge under six different working conditions and different service life respectively, the loss of tie rod force is 0, 5, 10, 15, 15, 20%, and 25%, respectively. The results show that the reliability of each component is the main arch rib arch pile foundation under each working condition, and the weakest part of the whole bridge appears in the pile bottom section. When the loss of tie bar force is 15, the safety grade of the system is less than three levels in any service life. In order to ensure the lowest safety grade of bridge, when the loss of tie bar force exceeds 15%, the replacement of tie rod should be carried out as soon as possible to support the project. Taking 10% loss of tie rod force as the initial state, four kinds of tie-bar replacement schemes are put forward: one side, two branches, three and four, all of which are replaced at the same time, and the vehicles under different schemes are released intermittently. At the same time, the change of mechanical behavior and reliability of the bridge under the four schemes are compared and analyzed during the intermittent construction. The results show that the control section stress, the deflection of bridge deck and the internal force of tie rod meet the requirements under each scheme; However, the reliability analysis shows that only option 1 / 2 is feasible, in addition, the construction time of scheme 2 can be shortened by about half compared with that of scheme 1. Therefore, it is suggested that option 2 be used to replace the tie bar.
【學位授予單位】：重慶交通大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：U445.7;U448.225
【參考文獻】
相關(guān)碩士學位論文 前1條
1 張志;系桿拱橋結(jié)構(gòu)構(gòu)件可靠度評估研究[D];合肥工業(yè)大學;2007年
，本文編號：2193260
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