本文選題：平頂直墻 + 淺埋暗挖�。� 參考：《北京工業(yè)大學(xué)》2014年碩士論文

【摘要】：平頂直墻結(jié)構(gòu)受頂部因缺乏拱效應(yīng),在開挖過程中易造成地表沉降值過大,甚至產(chǎn)生坍塌事故。因此,研究平頂直墻淺埋暗挖隧道施工對于地表沉降的影響,采取有效措施減小變形,以使道路等不至造成損害,是城市地鐵建設(shè)面臨的重要任務(wù),并具有重要施工指導(dǎo)意義。本文將以地鐵14號線大瓦窯站出入口的暗挖工程為依托,對砂卵石地層平頂直墻暗挖施工引起的地表沉降情況進(jìn)行研究,系統(tǒng)分析地表沉降的監(jiān)測結(jié)果,結(jié)合有限元理論研究暗挖施工對地表沉降的影響規(guī)律,確定主要影響因素,并進(jìn)一步對平頂直墻暗挖施工工法進(jìn)行優(yōu)化,尋求科學(xué)合理的地表沉降控制措施。在介紹淺埋暗挖工藝的基礎(chǔ)上,從采用的施工法、隧道的埋深(隧道覆土的厚度)、覆土或圍巖的巖性和質(zhì)量、隧道的截面形式、隧道襯砌的剛度和施工速度、后注漿的質(zhì)量和注漿壓力、施工降水等方面分析影響沉降的因素;以北京地鐵五號線某區(qū)間隧道工程的平頂直墻暗挖段作為工程依托,利用有限元計(jì)算,分析導(dǎo)洞暗挖寬度、導(dǎo)洞暗挖高度、導(dǎo)洞埋深、導(dǎo)洞壁厚及導(dǎo)洞周圍土體加固效果對地表沉降的影響;依托實(shí)際工程對導(dǎo)洞開挖引起的地表沉降進(jìn)行了有限元分析和監(jiān)測分析,并將兩種方法所得數(shù)據(jù)進(jìn)行對比分析。研究結(jié)果表明,地表沉降值隨著導(dǎo)洞寬度、高度的增大而增大,隨著導(dǎo)洞埋深、壁厚、周圍加固土體彈性模量的增大而減小。導(dǎo)洞寬度對地表沉降的影響可以分為三個(gè)區(qū)域,即明顯區(qū)、微弱區(qū)、顯著區(qū),在選擇洞口開挖寬度時(shí),為控制地表沉降的同時(shí)兼顧施工便利性,可在導(dǎo)洞寬度對地表沉降影響的微弱區(qū)選擇;超過一定高度的導(dǎo)洞需要采取一定的加固措施,防止地面沉降過大;當(dāng)導(dǎo)洞埋深較小,要注意采取防護(hù)措施,防止對地表的影響過大;增加導(dǎo)洞的壁厚,可以較為有效地控制地表路面的沉降,當(dāng)壁厚增加的一定的程度時(shí),一味的增加導(dǎo)洞壁厚,對控制地表沉降影響相當(dāng)小。
[Abstract]:Due to the lack of arch effect at the top of the flat top and straight wall structure, it is easy to cause excessive surface subsidence and even collapse in the process of excavation. Therefore, it is important to study the effect of shallow buried tunnel construction on the surface settlement of flat top straight wall, and take effective measures to reduce the deformation so as to make the road do not cause damage. It is the importance of urban subway construction. The task is of great significance for construction. This paper will study the surface subsidence caused by the dark excavation of the flat top straight wall of the sand gravel stratum, based on the dark excavation project of the entrance of the great tile station of the subway line 14, and systematically analyze the monitoring results of the surface subsidence, and study the influence of the underground excavation on the ground settlement with the finite element theory. Law, determine the main influencing factors, and further optimize the excavation method of flat top straight wall, seek scientific and reasonable control measures of surface subsidence. On the basis of shallow buried excavation technology, the construction method, buried depth of tunnel (the thickness of tunnel overlying soil), the lithology and quality of overlying soil or surrounding rock, section form of tunnel, tunnel The stiffness and construction speed of the lining, the quality and the grouting pressure of the post grouting, the construction precipitation and so on are used to analyze the factors that affect the settlement. Based on the underground excavation section of the flat top straight wall of a tunnel project in Beijing metro line five, the length of the excavation width, the depth of the guide hole, the depth of the guide hole, the thickness of the guide hole and the guide wall are analyzed by the finite element calculation. The effect of soil reinforcement effect on the surface subsidence around the cave; based on the actual engineering, the finite element analysis and monitoring analysis are carried out on the ground subsidence caused by the tunnel excavation, and the data obtained by the two methods are compared and analyzed. The results show that the surface subsidence value increases with the width of the guide hole, the height increase, and the depth of the tunnel and the thickness of the wall. The influence of the elastic modulus of the surrounding soil decreases. The influence of the width of the guide hole on the surface subsidence can be divided into three regions, that is, the obvious area, the weak area and the significant area. In the choice of the width of the tunnel opening, the settlement of the ground surface is controlled and the convenience is taken into consideration, and the influence of the width of the guide hole on the surface settlement can be selected; It is necessary to take some reinforcement measures to prevent the ground settlement too large. When the depth of the guide hole is small, it is necessary to take precautions to prevent the oversize of the surface, and to increase the wall thickness of the guide hole, which can effectively control the settlement of the surface of the surface of the surface, and increase the thickness of the guide hole when the wall thickness increases. The influence of surface subsidence is rather small.
【學(xué)位授予單位】：北京工業(yè)大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2014
【分類號】：U231.3;TU433

【參考文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前1條

1 李繼升;北京地鐵淺埋暗挖法施工引起地表沉降規(guī)律的研究[D];中國地質(zhì)大學(xué)(北京);2012年

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本文編號：1958138