本文選題：深基坑 + 數(shù)值模擬　； 參考：《安徽建筑大學》2015年碩士論文

【摘要】：近些年,城市人口不斷增加,城市交通擁擠問題越來越嚴重。我國很多大中城市都在修建地鐵,充分利用地下空間緩解交通問題。地鐵修建一般都是在人口眾多、建筑物密集的城市中進行的。而地鐵車站深基坑的深度一般都達到了十幾米以上,一旦發(fā)生事故,將會帶來嚴重的后果。因此,一定要確保地鐵施工過程安全,其主要就是保證地鐵車站深基坑在施工過程中穩(wěn)定性不發(fā)生破壞。采用數(shù)值分析可以彌補傳統(tǒng)的理論分析設計只能計算結果卻不能反映基坑開挖施工過程中受力和位移變化的缺點,而且可以預先發(fā)現(xiàn)基坑施工中危險薄弱的地方,提前做好防范措施。目前,合肥地鐵一號線和二號線正在施工。本文以合肥地鐵一號線明光路站深基坑施工為例,進行了以下方面的研究和分析:文章分析總結明挖法和蓋挖法的國內(nèi)外研究現(xiàn)狀,同時對深基坑的變形機理做了詳細的闡述,對支護結構的變形、地表沉降、坑底隆起等影響深基坑變形的主要因素進行了研究,總結了目前國內(nèi)外關于深基坑穩(wěn)定性理論的計算方法。在施工過程中,進行了詳細的監(jiān)測分析。對監(jiān)測數(shù)據(jù)整理,分析了圍護結構頂部、地連墻側移、地表沉降、建筑物沉降和立柱沉降的變化規(guī)律。在明光路站施工的過程中,采用了明挖法和局部蓋挖法相結合的施工方法,基坑最深處達到了22.8米。針對施工的實際情況,利用大型有限元分析軟件Midas GTS/NX對基坑開挖的施工過程進行了三維的數(shù)值模擬計算,并得出了施工地表沉降和圍護結構的變化規(guī)律。地表沉降的最大值出現(xiàn)在距離基坑邊緣15m附近的地方。地下連續(xù)墻的變形呈現(xiàn)兩邊小中間大的弓形曲線,最大值出現(xiàn)在約為基坑深度的三分之二位置。明光路橋段原方案采用明挖法施工,實際施工過程中為了減小對路面交通的影響,采用蓋挖法施工。對明光路橋標準段采用明挖法和蓋挖法分別進行了二維模擬,得出兩種施工方法下地表沉降、圍護結構和支撐軸力的變化規(guī)律,通過數(shù)據(jù)對比分析,得出明挖法更改為蓋挖法是合理安全的。并通過支護結構的優(yōu)化分析,對基坑支護的合理性進行了系統(tǒng)的分析,得出地連墻的嵌固深度35.2m,鋼支撐間距為6m是經(jīng)濟合理的。
[Abstract]:In recent years, the urban population continues to increase, urban traffic congestion problem is becoming more and more serious. Many large and medium-sized cities in China are building subways to make full use of underground space to alleviate traffic problems. Subway construction is generally carried out in cities with large populations and dense buildings. The depth of deep foundation pit of subway station is generally more than ten meters, once an accident occurs, it will bring serious consequences. Therefore, it is necessary to ensure the safety of subway construction process, which is mainly to ensure that the stability of the deep foundation pit of subway station will not be destroyed during the construction process. Numerical analysis can make up for the shortcomings of traditional theoretical analysis and design which can only calculate the results but can not reflect the variation of force and displacement in the excavation process of foundation pit, and can find the dangerous weak place in foundation pit construction in advance. Take precautions in advance. At present, Hefei Metro Line 1 and Line 2 are under construction. Taking the construction of deep foundation pit of Mingguang Road Station of Hefei Metro Line 1 as an example, this paper studies and analyzes the following aspects: this paper analyzes and summarizes the domestic and foreign research status of open excavation method and cover excavation method, and expounds in detail the deformation mechanism of deep foundation pit. The main factors affecting the deformation of deep foundation pit, such as deformation of supporting structure, ground subsidence and uplift of pit bottom, are studied, and the calculation methods of stability theory of deep foundation pit at home and abroad are summarized. In the process of construction, detailed monitoring and analysis are carried out. According to the monitoring data, the variation rules of the top of the enclosure structure, the lateral displacement of the ground connection wall, the surface settlement, the settlement of the building and the settlement of the column are analyzed. In the construction process of Mingguang Road Station, the combination of open excavation method and partial cover excavation method is adopted, and the deepest part of the foundation pit reaches 22.8 meters. In view of the actual situation of the construction, the 3D numerical simulation of the construction process of foundation pit excavation is carried out by using Midas GTS / NX, a large-scale finite element analysis software, and the variation law of the construction surface settlement and the surrounding structure is obtained. The maximum value of surface subsidence occurs about 15 m from the edge of foundation pit. The deformation of underground continuous wall shows a large bow curve between the two sides, and the maximum value appears at about 2/3 of the depth of foundation pit. In order to reduce the influence on road traffic, the original project of Mingguang Road is constructed with the method of open excavation. In order to reduce the influence on road traffic, the method of cover excavation is adopted in the actual construction process. The two dimensional simulation of the standard section of Mingguang Road and Bridge is carried out by using the open excavation method and the cover excavation method respectively. The variation rules of the ground surface settlement, the enclosure structure and the supporting axial force under the two construction methods are obtained, and the data are compared and analyzed. It is concluded that it is reasonable and safe to change the open excavation method to cover excavation method. Through the optimization analysis of the supporting structure, the rationality of foundation pit support is systematically analyzed. It is concluded that the embedded depth of the ground connecting wall is 35.2 m and the steel bracing distance is 6 m.
【學位授予單位】：安徽建筑大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：U231.3;TU94

【參考文獻】

相關期刊論文 前4條

1 楊曉杰;劉冬明;張帆;張保童;黃新生;韓巧云;;地鐵隧道明挖法施工基坑支護穩(wěn)定性研究[J];地下空間與工程學報;2010年03期

2 謝仁德;;蓋挖法和明挖法施工技術及優(yōu)缺點比較[J];地鐵與輕軌;1992年04期

3 王偉茂;;地鐵車站換乘段深基坑工程蓋挖法施工有限元法模擬分析[J];建筑施工;2008年04期

4 張耀東;龔曉南;;軟土基坑抗隆起穩(wěn)定性計算的改進[J];巖土工程學報;2006年S1期

相關碩士學位論文 前2條

1 楊翼;地鐵車站蓋挖順作法施工監(jiān)控量測與分析[D];西南交通大學;2005年

2 霍亞超;明蓋結合裝配式鋪蓋法地鐵車站施工幾個關鍵問題研究[D];北京交通大學;2012年

，

本文編號：2037190