软弱富水地层中浅埋暗挖隧道支护结构受力及地表沉降规律的研究
发布时间：2018-08-24 20:12
【摘要】：在软弱富水地层中进行浅埋暗挖隧道施工,支护结构和围岩易产生较大的变形甚至失稳,从而影响地表及周围环境。本文以东莞至惠州城际轨道交通工程GZH-5标段中GDK25+080-GDK33+022.303段为工程背景,开展软弱富水地层中浅埋暗挖隧道支护结构受力及地表沉降规律的研究,进行了以下研究工作：(1)采用一种水泥堵漏剂按1：0.8的水灰比配制模型试验用喷混凝土；(2)改进了注浆及喷混凝土设备,研制了能喷出雾状的喷混凝土喷头以及压力注浆花管。(3)开展了2组模型试验(第1组未进行全断面超前注浆,第2组进行了超前注浆),以CD工法进行开挖,模拟了隧道开挖、支护、拆除中隔墙全过程,对拱架内力及地表沉降进行量测,并对试验过程进行了数值模拟。通过研究取得以下成果：(1)通过模型试验,得到了隧道全断面超前注浆的地表隆起曲线,注浆压力采用30～50kPa时,地表最大隆起量可达1.8mm,对应实际工程隆起量45mm,超过浅埋暗挖法施工质量控制标准规定的10mm。(2)横向地表沉降曲线呈现Peck公式描述的正态分布曲线形式,最大沉降点偏向先开挖侧；模型试验地表最大沉降值为2.6mm(相当于实际工程65mm),数值计算地表最大沉降值为1.42mm(相当于实际工程35.5mm),均超过浅埋暗挖法施工质量控制标准规定的30mm。(3)地表沉降历时曲线表明,在开挖面前进至测点对应断面前所产生的地表沉降在总沉降中占很高的比例：模型试验的结果为83%,数值模拟为79.4%。其中,开挖-1D～0D(D为隧道宽度)段时产生的地表沉降的比例可达63%,因此,为控制地表沉降,应采用较强的超前支护手段,其中开挖到距测点1D时尤为重要。(4)隧道开挖对拱架弯矩及轴力产生明显影响的纵向距离约为1D～2D;拆除中隔墙会引起拱架受力状态产生较大变化；拆除中隔墙后,最大弯矩值出现在①区和④区,②区和③区弯矩值较小并出现有负弯矩；最大轴力出现均在④区,②区和③区轴力值较小,且会出现拉力。
[Abstract]:In the construction of shallow buried tunnel in weak water-rich stratum, the support structure and surrounding rock are prone to deform or even lose stability, thus affecting the surface and surrounding environment. In this paper, based on the background of GDK25 080-GDK33 022.303 in the GZH-5 section of Dongguan to Huizhou Intercity Rail Transit Project, the research on the force and ground subsidence law of shallow buried tunnel support structure in soft and water-rich ground is carried out. The following research works were carried out: (1) a cement plugging agent was used to prepare the model concrete for model test at the water / cement ratio of 1: 0.8; (2) the grouting and shotcrete equipment was improved. A spray concrete sprinkler and a pressure grouting tube are developed. (3) two groups of model tests are carried out (the first group has no full-section advance grouting, the second group has advanced grouting), and the tunnel excavation is simulated by CD method. In the whole process of supporting and removing the partition wall, the internal force and surface settlement of arch frame are measured, and the test process is simulated numerically. The results are as follows: (1) through the model test, the surface uplift curve of the full-section advance grouting tunnel is obtained. When the grouting pressure is 30~50kPa, The maximum uplift of the surface can reach 1.8 mm, corresponding to the actual engineering uplift of 45mm, which exceeds the 10mmm stipulated in the construction quality control standard of shallow buried excavation method. (2) the transverse surface settlement curve presents the normal distribution curve described by Peck formula, and the maximum settlement point is inclined to the first excavation side; The maximum surface settlement value of model test is 2.6mm (equivalent to actual engineering 65mm), and the maximum surface settlement value of numerical calculation is 1.42mm (equivalent to actual engineering 35.5mm), which is more than 30mm in the construction quality control standard of shallow buried excavation method. (3) the surface subsidence duration curve shows that, The surface settlement produced before the excavating surface advances to the corresponding section accounts for a high proportion of the total settlement: the result of the model test is 833 and the numerical simulation is 79.4. The proportion of ground subsidence caused by excavation of -1D / 0D (D is the width of tunnel) can reach 63. Therefore, in order to control the surface settlement, a strong advance support method should be adopted. (4) the longitudinal distance of tunnel excavation to the moment and axial force of arch frame is about 1D ~ 2D; removing the middle partition will cause great changes in the stress state of the arch frame; after removing the middle partition wall, the stress state of the arch frame will be changed greatly. The maximum moment values are smaller in zone 1 and 4, and have negative moment in region 2 and 3, and the maximum axial force is smaller in zone 2 and zone 3, and tensile force will occur.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U452.11;U455.7
本文编号：2201910
[Abstract]:In the construction of shallow buried tunnel in weak water-rich stratum, the support structure and surrounding rock are prone to deform or even lose stability, thus affecting the surface and surrounding environment. In this paper, based on the background of GDK25 080-GDK33 022.303 in the GZH-5 section of Dongguan to Huizhou Intercity Rail Transit Project, the research on the force and ground subsidence law of shallow buried tunnel support structure in soft and water-rich ground is carried out. The following research works were carried out: (1) a cement plugging agent was used to prepare the model concrete for model test at the water / cement ratio of 1: 0.8; (2) the grouting and shotcrete equipment was improved. A spray concrete sprinkler and a pressure grouting tube are developed. (3) two groups of model tests are carried out (the first group has no full-section advance grouting, the second group has advanced grouting), and the tunnel excavation is simulated by CD method. In the whole process of supporting and removing the partition wall, the internal force and surface settlement of arch frame are measured, and the test process is simulated numerically. The results are as follows: (1) through the model test, the surface uplift curve of the full-section advance grouting tunnel is obtained. When the grouting pressure is 30~50kPa, The maximum uplift of the surface can reach 1.8 mm, corresponding to the actual engineering uplift of 45mm, which exceeds the 10mmm stipulated in the construction quality control standard of shallow buried excavation method. (2) the transverse surface settlement curve presents the normal distribution curve described by Peck formula, and the maximum settlement point is inclined to the first excavation side; The maximum surface settlement value of model test is 2.6mm (equivalent to actual engineering 65mm), and the maximum surface settlement value of numerical calculation is 1.42mm (equivalent to actual engineering 35.5mm), which is more than 30mm in the construction quality control standard of shallow buried excavation method. (3) the surface subsidence duration curve shows that, The surface settlement produced before the excavating surface advances to the corresponding section accounts for a high proportion of the total settlement: the result of the model test is 833 and the numerical simulation is 79.4. The proportion of ground subsidence caused by excavation of -1D / 0D (D is the width of tunnel) can reach 63. Therefore, in order to control the surface settlement, a strong advance support method should be adopted. (4) the longitudinal distance of tunnel excavation to the moment and axial force of arch frame is about 1D ~ 2D; removing the middle partition will cause great changes in the stress state of the arch frame; after removing the middle partition wall, the stress state of the arch frame will be changed greatly. The maximum moment values are smaller in zone 1 and 4, and have negative moment in region 2 and 3, and the maximum axial force is smaller in zone 2 and zone 3, and tensile force will occur.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U452.11;U455.7
【参考文献】
中国期刊全文数据库 前6条
1 李勇;王文喜;;FLAC~(3D)在工程降水引起地面沉降分析中的应用[J];铁道标准设计;2008年10期
2 吴波,刘维宁,高波,索晓明,史玉新;深圳地铁区间隧道富水地层非降水施工技术研究[J];土木工程学报;2004年04期
3 漆泰岳;高波;马亮;;富水软土地层地铁开挖地表沉降离心模型试验[J];西南交通大学学报;2006年02期
4 李文江;孙明磊;朱永全;朱正国;李玉良;;软弱围岩隧道台阶法施工中拱脚稳定性及其控制技术[J];岩石力学与工程学报;2012年S1期
5 王明年,张建华;工程措施对控制隧道围岩变形的力学效果研究[J];岩土工程学报;1998年05期
6 周毅;李术才;李利平;赵岩;刘钦;原小帅;;地层条件对超大断面隧道软弱破碎围岩施工影响过程规律的数值模拟分析[J];岩土力学;2011年S2期
中国博士学位论文全文数据库 前1条
1 王戍平;破碎围岩隧道的模拟试验研究[D];浙江大学;2004年
中国硕士学位论文全文数据库 前3条
1 李晓洪;软弱围岩双连拱隧道施工力学研究[D];西南交通大学;2003年
2 李运来;软岩巷道变形的相似模型试验与计算方法的研究[D];安徽理工大学;2005年
3 王震;正阳隧道围岩变形与支护结构受力特性研究[D];重庆交通大学;2009年
，本文编号：2201910
本文链接：https://www.wllwen.com/kejilunwen/daoluqiaoliang/2201910.html
