【摘要】：輸氣管道在不良地質(zhì)環(huán)境下,表現(xiàn)出的潛在危險(xiǎn)性已經(jīng)引起了人們的注意,管道中輸送的易燃、易爆介質(zhì),在管道破損后存在著極高的潛在危害。為此,在黃土地區(qū),研究黃土暗穴對(duì)管道的影響具有重要的理論意義和實(shí)用價(jià)值。本文針對(duì)西氣東輸二線(xiàn)DL069潼關(guān)段,討論研究區(qū)的地質(zhì)條件、環(huán)境條件、管周黃土暗穴特征、發(fā)育規(guī)律及成因。采用現(xiàn)場(chǎng)調(diào)查、勘探、室內(nèi)外試驗(yàn)及理論計(jì)算與數(shù)值模擬分析,對(duì)管周黃土暗穴的發(fā)育規(guī)律、成因機(jī)制及管道的受力關(guān)系進(jìn)行分析,得到一些有價(jià)值的結(jié)果與結(jié)論。(1)基于研究區(qū)管周黃土暗穴發(fā)育特征,提出了管周黃土暗穴發(fā)育原因,包括(a)內(nèi)因(土性條件、節(jié)理裂隙、地下水);(b)外因(回填土、降雨、植被覆蓋率及防排水構(gòu)筑物)。提出了管周黃土暗穴“回填土沉陷-管底土流失”形成機(jī)理。大致可以概括為“回填土沉陷——沉陷負(fù)地形聚水——沉陷裂隙形成——徑流水沿著沉陷裂隙下滲——管道頂部陷穴形成——管土接觸間隙增大——管底土流失——管周黃土暗穴形成”。(2)建立管道與管周黃土的流固耦合模型,探究了在降雨模式下,地表徑流下滲時(shí),管道與管周黃土關(guān)鍵部位的應(yīng)力、應(yīng)變的變化特點(diǎn)。得到管壁應(yīng)力大于管底應(yīng)力。應(yīng)變由管中心向兩邊遞減,但在回填土與原狀土的交界處最大,這說(shuō)明在原狀土與回填土的交界處,接觸間隙是導(dǎo)致水流下滲形成陷穴的主要通道。闡釋了管周黃土暗穴的形成機(jī)制。(3)分析管道上覆土荷載、內(nèi)部壓力及溫差應(yīng)力�；诠芡磷饔脵C(jī)制,建立無(wú)固定端單跨管道模型。假設(shè)管道(型號(hào)X80級(jí)),管頂埋深2m,通過(guò)理論計(jì)算,得到管道極限安全跨度為37m,可為西氣東輸管道的后期維護(hù)提供借鑒。
[Abstract]:Under the bad geological environment, the potential danger of gas pipeline has attracted people's attention. The flammable and explosive medium transported in the pipeline has a high potential harm after the pipeline is damaged. Therefore, it is of great theoretical and practical value to study the influence of hidden loess caverns on pipelines in loess region. In this paper, the geological conditions, environmental conditions, characteristics of loess underground caverns around Guanzhou, development rules and causes of the study area are discussed in view of the DL069 Tongguan section of West to East Gas Transmission Line 2. By means of field investigation, exploration, indoor and outdoor tests, theoretical calculation and numerical simulation analysis, this paper analyzes the development law, genetic mechanism and stress relationship of the loess underground caverns around the pipe. Some valuable results and conclusions are obtained. (1) based on the characteristics of the development of loess underground caverns around the pipe in the study area, the reasons for the development of the loess underground caverns around the pipe are put forward, including the internal causes of (a) (soil conditions, joints and fissures,); (b) external causes of groundwater (backfill, rainfall), etc. Vegetation coverage and waterproofing and drainage structures) The formation mechanism of "backfill soil subsidence-pipe subsoil loss" in loess hidden caverns around pipe is put forward. It can be summarized as follows: "backfill subsidence --subsidence negative topography accumulation -subsidence fissure formation -runoff water infiltration along the subsidence fissures-formation of caverns at the top of the pipeline-increase of tube-soil contact gap-loss of subsoil in the pipe The formation of underground holes in the loess around the pipe. (2) the fluid-solid coupling model between the pipeline and the loess around the pipe is established. The variation characteristics of stress and strain in the key part of loess around pipeline and pipe were studied under rainfall model and surface runoff infiltration. The results show that the wall stress is greater than the bottom stress. The strain decreases from the center of the pipe to the two sides, but the maximum is at the junction between the backfill and the undisturbed soil, which indicates that the contact gap is the main channel leading to the infiltration of the water flow to form caverns at the junction of the backfill and the backfill. The formation mechanism of loess caverns around the pipe is explained. (3) the soil load, internal pressure and temperature difference stress on the pipe are analyzed. Based on the action mechanism of pipe and soil, a single span pipe model without fixed end is established. Assuming that the pipe (type X80 grade) is buried at the top of the pipe at a depth of 2 m, the ultimate safety span of the pipeline is 37 m through theoretical calculation, which can be used for reference in the later maintenance of the West-East Gas Pipeline.
【學(xué)位授予單位】：西安科技大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類(lèi)號(hào)】：TE973

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 蔡云廷;;山西鐵路沿線(xiàn)黃土崩解性試驗(yàn)研究[J];鐵道工程學(xué)報(bào);2016年04期

2 鄧思遠(yuǎn);楊其新;蔣雅君;陳浩;;FLAC3D流固耦合滲流模型探討[J];隧道建設(shè);2016年02期

3 劉林;李金峰;王小平;;黃土高原溝壑丘陵區(qū)溝道侵蝕與洞穴侵蝕特征[J];水土保持通報(bào);2015年01期

4 魏孔瑞;姚安林;張照旭;聶秋露;谷醒林;;埋地油氣管道懸空沉降變形失效評(píng)估方法研究[J];中國(guó)安全科學(xué)學(xué)報(bào);2014年06期

5 周亞麗;李敏;武廣良;;潼關(guān)氣象站周邊環(huán)境變化對(duì)氣象要素影響的事實(shí)分析[J];陜西氣象;2013年05期

6 雒林林;張超;;黃土陷穴對(duì)長(zhǎng)輸管道建設(shè)的危害與防治[J];油氣田地面工程;2013年09期

7 尹法波;杜曼;趙東風(fēng);;地震地區(qū)長(zhǎng)輸天然氣管道失效風(fēng)險(xiǎn)分析與評(píng)價(jià)[J];油氣儲(chǔ)運(yùn);2013年05期

8 于東升;宋漢成;;油氣管道懸空沉降變形失效評(píng)估[J];油氣儲(chǔ)運(yùn);2012年09期

9 趙東風(fēng);申玉琪;趙志強(qiáng);張佑明;孟亦飛;;基于事故發(fā)展與控制的隱患分級(jí)方法[J];中國(guó)安全科學(xué)學(xué)報(bào);2012年04期

10 張仲福;侯云龍;;蘭鄭長(zhǎng)輸油管道甘肅段地質(zhì)災(zāi)害成因分析及其治理措施[J];地下水;2011年04期

相關(guān)博士學(xué)位論文 前1條

1 劉愛(ài)文;基于殼模型的埋地管線(xiàn)抗震分析[D];中國(guó)地震局地球物理研究所;2002年

相關(guān)碩士學(xué)位論文 前3條

1 康錦輝;黃土洞穴物理潛蝕機(jī)理試驗(yàn)研究[D];長(zhǎng)安大學(xué);2010年

2 李影;懸索式跨越管道力學(xué)分析及安全性研究[D];大慶石油學(xué)院;2010年

3 劉建平;陜西省子長(zhǎng)地區(qū)黃土的潛蝕試驗(yàn)研究[D];中國(guó)地質(zhì)大學(xué);2008年

，

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