【作者】 荣亮；

【导师】 彭立敏； 杨伟超； 赵丹；

【作者基本信息】 中南大学 ， 工程（专业学位）， 2022， 硕士

【摘要】 顶管技术是一项掘进面持续推进和管节连续顶进铺设相结合的隧道施工技术,该施工方法具有省时、高效、安全,综合造价低等突出优点。随着城市化建设的持续推进和顶管技术的不断发展,顶管隧道施工越来越呈现异性大断面、浅覆土、长距离和多孔并行的方向发展,并日益已经成为我国城市地铁出入口和城市主干线交叉段的主要施工方法之一。本文依托郑州红专路下穿中州大道隧道工程,开展超浅埋大断面多孔并行矩形顶管施工关键技术研究。论文的主要工作如下:(1)针对长距离大断面顶管隧道顶推力过大的问题,提出顶进过程中采用触变泥浆和合理控制注浆施工参数的方法,可有效降低长距离大断面顶管隧道顶推力过大的问题,其中膨润土含量为6%、CMC含量为0.1%,纯碱的含量为0.3%,PHP的含量为0.2%的触变泥浆配合比是体现出较好的经济技术优势;注浆孔的数量及其分布方式应根据隧道断面确定,注浆压力应根据地层压力确定。(2)针对浅埋条件下多孔并行的小间距矩形顶管隧道地表沉降问题,采用多洞间隔跳孔的总体施工顺序,且相临隧道掘进面的纵向间距控制在24m可有效消除多孔并行隧道施工对地表沉降的不良影响,同时大幅提高施工效率;顶管推进过程中顶推力的动态控制、推进速度、出土量和注浆压力等参数对地表沉降也有重要影响,此外在前基座上安装一套止退装置,稳定停机过程中管节和机头也可有效降低地表沉降。(3)提出了以铰接纠偏、注浆纠偏为主,以双螺旋机出土纠偏、六刀盘控制、顶进油缸控制措施为辅的盾构顶管施工姿态控制策略,实现了长距离条件下多孔并行小间距顶管隧道姿态的精确控制。大断面顶管隧道洞门采用两道帘幕橡胶和两道折页板的洞门密封形式,且在洞门密封完全包裹顶管机后,及时进行触变泥浆注浆,快速形成泥浆套,以及始发掘进速度控制5mm/min左右可达到最佳洞门密封效果。图115幅,表19个,参考文献159篇更多还原

【Abstract】 Pipe jacking technology is a tunnel construction technology that combines continuous advancement of the tunnel face and continuous jacking and laying of pipe sections.This construction method has outstanding advantages such as time saving,high efficiency,safety,and low comprehensive cost.With the continuous advancement of urbanization construction and the continuous development of pipe jacking technology,the construction of pipe jacking tunnels has increasingly developed in the direction of heterosexual large-section,shallow overburden,long-distance and porous parallel tunnels,and has increasingly become my country’s urban subway entrances and exits.One of the main construction methods for the intersection of urban trunk lines.Relying on the tunnel project of Zhengzhou Hongzhuan Road passing through Zhongzhou Avenue,this paper studies the key technology of super-shallow buried and large-section porous parallel rectangular pipe jacking.The main work of the paper is as follows:(1)Aiming at the problem of excessive jacking thrust in long-distance and large-section pipe jacking tunnels,the method of using thixotropic mud and reasonably controlling grouting construction parameters in the jacking process can effectively reduce the excessive jacking thrust of long-distance and large-section pipe jacking tunnels.The big problem,in which the content of bentonite is 6%,the content of CMC is 0.1%,the content of soda ash is 0.3%,the content of PHP is 0.2%,and the content of water is 93.4%.The number and distribution of different grouting holes are arranged according to the size of the tunnel section,and the grouting pressure should be determined according to the formation pressure.(2)Aiming at the surface settlement problem of porous parallel smallspaced rectangular pipe jacking tunnels under shallow burial conditions,the overall construction sequence of multi-hole spaced jump holes is adopted,and the longitudinal spacing of adjacent tunnel excavation surfaces is controlled at 24 m,which can effectively eliminate porous parallel tunnels.The adverse effect of construction on the surface settlement,and at the same time,the construction efficiency is greatly improved;the dynamic control of the jacking thrust,the advancing speed,the excavation volume and the grouting pressure during the pipe jacking process also have an important impact on the surface settlement.In addition,the installation on the front foundation A set of anti-return device can effectively reduce the surface settlement of the pipe section and the machine head during the stable shutdown process.(3)The construction attitude control strategy of shield pipe jacking is proposed,which is mainly based on articulation rectification and grouting rectification,supplemented by double-screw excavation rectification,sixcutter control,and jacking cylinder control measures.Precise control of the attitude of a multi-hole parallel small-pitch pipe jacking tunnel.The hole door seal is optimized to the hole door seal form of two curtain rubbers and two hinge plates.At the same time,after the hole door seal completely wraps the pipe jacking machine,the thixotropic mud grouting is carried out in time to quickly form a mud sleeve and start the pipe jacking machine.The best sealing effect of the hole can be achieved by controlling the excavation speed of about 5mm/min..更多还原