【摘要】：對(duì)于山區(qū)公路路基拓寬改建工程,控制新舊路基頂面差異沉降和保證路基穩(wěn)定性至關(guān)重要。圍繞著這一工程目的,本文開展了基于土-結(jié)構(gòu)相互作用的山區(qū)公路路基拓寬改建力學(xué)行為的數(shù)值模擬及其工程處治對(duì)策研究。山區(qū)公路路基單側(cè)拼接式拓寬改建多下設(shè)包括衡重式擋土墻在內(nèi)的支擋建筑物于新路基外側(cè)。運(yùn)用Phase2有限元軟件,引入Joint單元,構(gòu)建描述土-墻相互作用的數(shù)值模型,采用兩步走、墻面施加非零位移約束方式模擬擋土墻平動(dòng)加繞墻趾轉(zhuǎn)動(dòng)(RBT)主動(dòng)外傾變位,分析擋土墻不同主動(dòng)外傾變位量對(duì)新舊路基頂面差異沉降的影響,并與土工離心模型試驗(yàn)成果進(jìn)行驗(yàn)證比較。結(jié)果表明：下設(shè)的剛性擋土墻與新老路基相互作用,共同依存。數(shù)值模擬反映當(dāng)主動(dòng)外傾量與墻高之比為1%～3%時(shí),由擋土墻主動(dòng)外傾變位產(chǎn)生的附加差異沉降占總差異沉降的51%～67%。結(jié)合山區(qū)公路路基拓寬改建多下設(shè)剛性擋土墻的特殊性,運(yùn)用Phase2有限元軟件,采用強(qiáng)度折減法,引入joint, structural interface單元,對(duì)山區(qū)公路路基拓寬加筋穩(wěn)定性開展數(shù)值模擬,探究填土、土工格柵、土-格柵相互作用三者動(dòng)態(tài)演變規(guī)律及對(duì)路基穩(wěn)定性的影響,并以土工離心模型試驗(yàn)成果進(jìn)行驗(yàn)證。結(jié)果表明：鋪設(shè)土工格柵可削減路基面沉降、限制墻體外傾,增強(qiáng)路基穩(wěn)定性,并且填土、土工格柵、土-格柵界面對(duì)路基穩(wěn)定性的影響權(quán)重動(dòng)態(tài)變化。隨著強(qiáng)度折減系數(shù)SRF的增加,填土-土工格柵界面單元雖然會(huì)滑移失效,但未決定路基穩(wěn)定性,而衡重臺(tái)外邊緣上層位處土工格柵被拉斷失效,軸向拉力驟降,直接導(dǎo)致拓寬路基失穩(wěn)破壞。結(jié)合我國已完成的路基拓寬工程實(shí)踐經(jīng)驗(yàn)及相關(guān)領(lǐng)域研究,初步提出了山區(qū)公路路基拓寬改建工程對(duì)策的基本技術(shù)思路,總結(jié)了控制新舊路基頂面差異沉降及路基穩(wěn)定性的工程處治措施。主要包括：路基內(nèi)部加筋,新舊路基結(jié)合部臺(tái)階設(shè)置,路基填料選擇與壓實(shí)工藝控制,半路半橋結(jié)構(gòu)設(shè)置,擋土墻設(shè)置,地基處理,拓寬路基邊坡防護(hù)等工程處治對(duì)策。
[Abstract]:It is very important to control the differential settlement of new and old roadbed top surface and ensure the stability of roadbed for the widening and rebuilding of highway roadbed in mountainous area. Based on the soil-structure interaction, the numerical simulation of the mechanical behavior of roadbed widening and rebuilding in mountainous area and the countermeasures of engineering treatment are carried out in this paper. In the mountainous area highway roadbed, most of the retaining structures, including the counterweight retaining wall, are located on the outside of the new roadbed. Using Phase2 finite element software and introducing Joint element, a numerical model to describe the soil-wall interaction is constructed. Using two-step walk and non-zero displacement constraint on the wall surface, the lateral movement of retaining wall and the rotation of (RBT) active extraversion around the toe of the wall are simulated. The influence of different active extraversion of retaining wall on the differential settlement of new and old roadbed top surface is analyzed and compared with the results of geotechnical centrifuge model test. The results show that the rigid retaining wall interacts with the new and old subgrade and depends on each other. Numerical simulation shows that when the ratio of active extraversion to wall height is 1 ~ 3, the additional differential settlement caused by active extraversion of retaining wall accounts for 51% of the total differential settlement. Combined with the particularity of the rigid retaining wall under the widening and rebuilding of highway roadbed in mountainous area, using Phase2 finite element software, using strength reduction method and introducing joint, structural interface element, the stability of widening and reinforcement of highway roadbed in mountainous area is simulated numerically, and the fill soil is explored. The dynamic evolution law of geogrid and soil-grid interaction and its influence on the stability of roadbed are verified by the results of geotechnical centrifugal model test. The results show that laying geogrid can reduce the settlement of roadbed, limit the external inclination of wall, enhance the stability of roadbed, and dynamic change of the influence weight of soil, geogrid and soil-grid interface on the stability of roadbed. With the increase of strength reduction coefficient (SRF), the interfacial element of filling earth and geogrid will slip, but it will not determine the stability of roadbed, but the geogrid will be broken and the axial tensile force will drop sharply at the upper part of the outer edge of the counterbalance platform. It directly leads to the failure of widening roadbed. Based on the practical experience of roadbed widening project and the research on related fields, the basic technical thinking of roadbed widening and rebuilding engineering in mountainous area is put forward. The engineering treatment measures to control the differential settlement and stability of the new and old subgrade are summarized. It mainly includes: the interior reinforcement of the roadbed, the installation of steps in the new and old roadbed, the selection of subgrade filler and the control of compaction technology, the construction of half-bridge structure, the setting of retaining wall, the treatment of foundation, the widening of subgrade slope protection and so on.
【學(xué)位授予單位】：西南交通大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：U416.1

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 李中海;;路基拓寬中的常見病害分析及加筋處治[J];山西建筑;2014年28期

2 楊和平;;極限平衡法與有限元強(qiáng)度折減法對(duì)某公路邊坡?lián)跬翂Ψ�(wěn)定性分析[J];公路工程;2012年03期

3 孫平;劉云;芮勇勤;;高速公路軟土路基拓寬處治數(shù)值分析[J];中外公路;2012年03期

4 錢勁松;凌建明;;軟土地區(qū)公路拓寬工程的力學(xué)響應(yīng)分析[J];地下空間與工程學(xué)報(bào);2010年03期

5 何禮彪;金亮星;;湖區(qū)公路拓寬工程處治技術(shù)應(yīng)用分析及監(jiān)測[J];鐵道科學(xué)與工程學(xué)報(bào);2009年05期

6 楊有輝;湯東;鄧昌中;;路基拓寬工程中陡路堤工程特性的有限元分析[J];中外公路;2009年02期

7 蘇德俊;詹勇;;山區(qū)公路改擴(kuò)建工程道路縱向開裂原因分析及防治[J];交通科技;2009年01期

8 楊建國;賈學(xué)明;王俊杰;;山區(qū)公路剛性擋墻常見病害成因及加固方法[J];重慶交通大學(xué)學(xué)報(bào)(自然科學(xué)版);2008年S1期

9 萬智;鄧宗偉;劉寶琛;吳亞中;;山區(qū)拓寬公路擋土墻路基的受力與變形特征分析[J];巖土力學(xué);2007年05期

10 蔣鑫;邱延峻;凌建明;;異型斷面路基路面綜合設(shè)計(jì)理論研究進(jìn)展[J];中外公路;2007年02期

相關(guān)博士學(xué)位論文 前1條

1 鄧云潮;高速公路擴(kuò)寬路基綜合防排水系統(tǒng)研究[D];長安大學(xué);2012年

相關(guān)碩士學(xué)位論文 前10條

1 耿建宇;公路路基拓寬改建力學(xué)行為及典型工程對(duì)策研究[D];西南交通大學(xué);2013年

2 楊靜;山區(qū)公路路基改擴(kuò)建技術(shù)研究[D];重慶交通大學(xué);2013年

3 李磊;山區(qū)公路改擴(kuò)建路基變形特性及穩(wěn)定性研究[D];長沙理工大學(xué);2012年

4 牛強(qiáng);西寶高速公路改擴(kuò)建新舊路基結(jié)合部處治技術(shù)[D];長安大學(xué);2012年

5 李輝;土工格柵在西藏地區(qū)公路改擴(kuò)建工程中的應(yīng)用研究[D];武漢理工大學(xué);2012年

6 王春元;山區(qū)公路改擴(kuò)建工程路基拓寬技術(shù)研究[D];重慶交通大學(xué);2012年

7 游濤;基于結(jié)構(gòu)—巖土共同作用的道路懸臂結(jié)構(gòu)計(jì)算方法研究[D];重慶交通大學(xué);2011年

8 劉長喜;山區(qū)道路懸挑結(jié)構(gòu)與巖土的共同作用研究[D];重慶交通大學(xué);2009年

9 張家國;衡重式擋土墻受力及變形特性離心模型實(shí)驗(yàn)研究[D];西南交通大學(xué);2004年

10 章定文;軟土地基上高速公路擴(kuò)建工程變形特性研究[D];東南大學(xué);2004年

，

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