發(fā)布時(shí)間：2018-02-28 06:57

  本文關(guān)鍵詞： 地層變形 既有橋梁 遮攔效應(yīng) 破壞模式 樁基可靠度 橋梁控制標(biāo)準(zhǔn) 動(dòng)態(tài)控制體系 主動(dòng)頂升 遺傳算法 反分析預(yù)測(cè)　出處：《北京交通大學(xué)》2015年碩士論文　論文類(lèi)型：學(xué)位論文

【摘要】：隨著城市現(xiàn)代化進(jìn)程的不斷發(fā)展,新建隧道穿越既有橋梁的情形越來(lái)越不可避免,而由于隧道開(kāi)挖產(chǎn)生的地層變形和應(yīng)力釋放必然會(huì)對(duì)既有橋梁產(chǎn)生擾動(dòng),從而威脅橋梁的使用和安全,因此,探究城市暗挖隧道穿越既有橋梁的安全控制理論和方法具有重要的現(xiàn)實(shí)意義。 本論文在對(duì)國(guó)內(nèi)外相關(guān)文獻(xiàn)資料進(jìn)行廣泛調(diào)研的基礎(chǔ)上,以北京地鐵7號(hào)線工程為背景,采用理論分析、數(shù)值模擬以及現(xiàn)場(chǎng)實(shí)測(cè)相結(jié)合的方法,對(duì)城市暗挖隧道穿越既有橋梁的安全控制方法進(jìn)行了深入系統(tǒng)的研究,得到了如下結(jié)論： (1)在分析地層變形與既有單樁相互作用關(guān)系的基礎(chǔ)上,對(duì)隧道開(kāi)挖條件下既有群樁的變形特性進(jìn)行了詳細(xì)的闡述,并采用數(shù)值模擬重點(diǎn)分析了群樁的遮攔效應(yīng),認(rèn)為群樁的變形模式和受力特性明顯區(qū)別于單樁,而呈現(xiàn)出其獨(dú)有的特點(diǎn)。 (2)從承臺(tái)的作用和土拱效應(yīng)兩方面論述了被動(dòng)群樁受力和變形特性的特殊性。即在隧道開(kāi)挖條件下,一方面承臺(tái)對(duì)各個(gè)樁基的荷載進(jìn)行了均衡化的再分配,另一方面對(duì)低位承臺(tái)而言,承臺(tái)還會(huì)改變樁基的荷載傳遞路徑；而土拱效應(yīng)則會(huì)促使樁間土體發(fā)生應(yīng)力遷移,從而在局部造成樁基的應(yīng)力集中,最終導(dǎo)致樁基受力和變形特性的改變。 (3)在考慮隧道開(kāi)挖對(duì)既有樁基承載力影響的基礎(chǔ)上,建立了樁基承載力的可靠度功能函數(shù),并采用matlab編寫(xiě)的響應(yīng)面計(jì)算程序?qū)λ淼篱_(kāi)挖條件下樁基承載力的失效概率進(jìn)行了計(jì)算。 (4)在對(duì)差異沉降下不同形式橋梁進(jìn)行受力和變形特性研究的基礎(chǔ)上,提出了基于損傷評(píng)估的既有橋梁控制標(biāo)準(zhǔn)的確定方法。 (5)從傳統(tǒng)防護(hù)和主動(dòng)防護(hù)兩方面對(duì)隧道穿越既有橋梁施工的安全性控制原理進(jìn)行了闡述。 建立了新型的隧道、土體、樁基、上部結(jié)構(gòu)四者之間的相互作用關(guān)系,并提出了基于主動(dòng)頂升的新型的橋梁主動(dòng)防護(hù)方法。 (6)建立了完整的隧道鄰近既有橋梁施工的動(dòng)態(tài)控制體系,并形成了該系統(tǒng)的技術(shù)流程。其核心在于橋梁風(fēng)險(xiǎn)狀態(tài)的判定及其應(yīng)對(duì)控制措施的選擇。通過(guò)該控制體系可以提前對(duì)橋梁的穿越風(fēng)險(xiǎn)進(jìn)行判定,并及時(shí)采取應(yīng)對(duì)措施,從而達(dá)到保證被穿越橋梁安全的目的。 (7)針對(duì)常規(guī)加固措施只能被動(dòng)應(yīng)對(duì)、無(wú)法主動(dòng)補(bǔ)償樁基沉降的現(xiàn)狀,研發(fā)了隧道穿越既有橋梁的主動(dòng)頂升成套技術(shù)。該技術(shù)主要分為頂升方案設(shè)計(jì)、頂升系統(tǒng)布置、頂升監(jiān)測(cè)系統(tǒng)、頂升施工、清場(chǎng)恢復(fù)五個(gè)步驟。 (8)在隧道穿越既有橋梁施工過(guò)程中,針對(duì)暗挖法隧道施工的具體特點(diǎn),提出了基于反分析預(yù)測(cè)的動(dòng)態(tài)預(yù)測(cè)控制方法。該方法是將變位分配和反分析預(yù)測(cè)結(jié)合在一起的一種動(dòng)態(tài)控制方法,能夠?qū)崿F(xiàn)穿越施工過(guò)程中的科學(xué)預(yù)警、分級(jí)控制和主動(dòng)應(yīng)對(duì),從而最大限度的避免了風(fēng)險(xiǎn)累計(jì),防止危險(xiǎn)發(fā)生。
[Abstract]:With the continuous development of urban modernization, it is more and more inevitable that new tunnels pass through existing bridges. However, the formation deformation and stress release caused by tunnel excavation will inevitably disturb the existing bridges. Therefore, it is of great practical significance to explore the theory and method of safety control for urban tunneling through existing bridges. In this paper, based on the extensive investigation of domestic and foreign literature, taking the Beijing Metro Line 7 project as the background, the method of combining theoretical analysis, numerical simulation and field measurement is adopted. In this paper, the safety control methods of urban tunnels crossing existing bridges are studied in depth and systematically, and the following conclusions are obtained:. 1) on the basis of analyzing the interaction between stratum deformation and existing single pile, the deformation characteristics of existing pile group under the condition of tunnel excavation are expounded in detail, and the blocking effect of group pile is analyzed by numerical simulation. It is considered that the deformation mode and mechanical characteristics of pile group are obviously different from that of single pile, but show their unique characteristics. (2) the particularity of the force and deformation characteristics of the passive pile group is discussed from the two aspects of the action of the cap and the soil arch effect, that is, under the condition of tunnel excavation, on the one hand, the load of each pile foundation is redistributed by equalization of the pile cap. On the other hand, for the low pile cap, the pile cap will change the load transfer path of the pile foundation, and the soil arch effect will promote the stress transfer between the piles, thus causing the stress concentration of the pile foundation locally. Finally, it leads to the change of load and deformation characteristics of pile foundation. On the basis of considering the influence of tunnel excavation on the bearing capacity of existing pile foundation, the reliability function function of pile foundation bearing capacity is established. The failure probability of pile foundation bearing capacity under the condition of tunnel excavation is calculated by using the response surface calculation program written by matlab. 4) based on the study of the stress and deformation characteristics of different types of bridges under differential settlement, a method for determining the control standards of existing bridges based on damage assessment is proposed. The paper expounds the safety control principle of tunnel crossing existing bridge construction from two aspects of traditional protection and active protection. A new type of interaction relationship among tunnel, soil, pile foundation and superstructure is established, and a new active protection method based on active lifting is proposed. A complete dynamic control system for the construction of existing bridges adjacent to the tunnel is established. The core of the system is the determination of bridge risk state and the choice of control measures. Through the control system, the bridge crossing risk can be judged in advance, and the corresponding measures can be taken in time. In order to ensure the safety of bridge crossing. In view of the fact that conventional reinforcement measures can only deal with the settlement of pile foundation passively and can not compensate the settlement of pile foundation actively, a complete set of active lifting technology for tunnel crossing existing bridges is developed. The technology is mainly divided into the design of jacking scheme and the arrangement of lifting system. Top-up monitoring system, jacking construction, field recovery five steps. In the construction process of tunnel crossing existing bridges, aiming at the concrete characteristics of tunneling construction, This paper presents a dynamic predictive control method based on back-analysis and prediction. The method is a dynamic control method which combines displacement assignment with back-analysis prediction. It can realize scientific early warning, hierarchical control and active response in the process of traversing construction. Thus to avoid risk accumulation to the maximum extent, prevent the occurrence of risk.
【學(xué)位授予單位】：北京交通大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類(lèi)號(hào)】：U456.3;U447

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 韋凱;雷震宇;周順華;;盾構(gòu)隧道下穿地下管線的變形控制因素分析[J];地下空間與工程學(xué)報(bào);2008年02期

2 彭坤;陶連金;高玉春;王楓;黃俊;;盾構(gòu)隧道下穿橋梁引起樁基變位的數(shù)值分析[J];地下空間與工程學(xué)報(bào);2012年03期

3 蘇潔;張頂立;牛曉凱;;地鐵淺埋暗挖法穿越既有橋梁施工變形控制[J];北京工業(yè)大學(xué)學(xué)報(bào);2009年05期

4 郭艷芬;楊圣超;張永水;韓鳳萍;萬(wàn)飛;;簡(jiǎn)支轉(zhuǎn)連續(xù)梁橋支座更換新方法的仿真分析[J];公路;2009年07期

5 潘婷;王健;楊廣武;;新建隧道穿越既有橋梁樁基時(shí)的主動(dòng)預(yù)支護(hù)技術(shù)[J];北京建筑工程學(xué)院學(xué)報(bào);2012年03期

6 王麗;鄭剛;;盾構(gòu)施工對(duì)3×3群樁的沉降、變形及樁側(cè)摩阻力的影響[J];大連交通大學(xué)學(xué)報(bào);2013年01期

7 袁臻;朱文霞;肖漢;;PLC同步頂升系統(tǒng)在高速公路橋梁改造中的應(yīng)用[J];中外公路;2013年05期

8 楊廣武;趙江濤;蘇潔;;地鐵施工對(duì)既有橋梁樁基的影響研究[J];都市快軌交通;2014年03期

9 呂高峰;劉德國(guó);;復(fù)合錨桿樁加固橋梁樁基方案分析[J];都市快軌交通;2013年05期

10 管自立;;疏樁基礎(chǔ)設(shè)計(jì)實(shí)例分析與探討(一)[J];建筑結(jié)構(gòu);1993年10期

相關(guān)博士學(xué)位論文 前1條

1 章榮軍;土體開(kāi)挖引起的鄰近受荷樁基附加響應(yīng)分析[D];華中科技大學(xué);2011年

，

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