【作者】 张弛；

【导师】 刘争平；

【作者基本信息】 西南交通大学 ， 地球探测与信息技术， 2012， 硕士

【摘要】 近年来,随着社会经济的不断发展,城市化的不断推进,城市规模不断扩大,为了实现可持续发展战略,除了向城市道路发展,还应该对地下空间进行开发和利用,修建地铁、轻轨成为城市发展的历史必然。然而随着地铁的大量兴建,也产生了一些工程技术问题,如地铁盾构施工引起的地表沉陷。地铁盾构施工是在岩土体内部进行的,隧道的开挖施工会不可避免地扰动地下岩土体,破坏原有的平衡状态,而向新的平衡状态转化。随着盾构的进行,地层损失引起的不密实带和空洞逐渐向上发展,在同步灌浆不足的情况下引起地表沉陷,地表沉陷到一定的程度,将影响地面结构物的安全和地下管线的正常使用。成都地区工程地质条件特殊,为富水砂卵石地层,砂卵石土中卵石含量高,粒径大,含漂石,石质强度高,砂质充填,卵石间的粘结力差,因此更加容易形成地表沉陷。在地铁1号线施工过程中,产生的地表沉陷尤为严重。因此,在地铁2号线盾构施工过程中,实时的查明扰动带引起的不密实带和空洞,并对治理质量进行评价,是确保盾构施工安全和公共安全的重要保障。探地雷达法主要基于高频电磁波在介质中传播和在电性突变界面上的反射特性,进行无损探测的一种物探方法。成都地铁2号线西延伸线犀浦站至天府广场站的左右线合计约24.471公里,位于成都市区,人流量大,而探底雷探地雷达具有速度快,效率高,无损且对周边环境影响小等优点,因此采用探底雷达探测成都地铁2号线盾构施工地层扰动带。本文主要研究了以下几个方面的内容：1.探地雷达基本原理和资料处理方法；2.盾构施工扰动带前期的试验,如地下水矿化度对探地雷达影响试验,地表探测深度试验和隧道管片试验等；3.制定具体的地表和隧道拱顶探测方案；4.通过典型实例归纳分析了地下空洞和不密实带的雷达响应特征,并对地下空洞处灌浆处理后进行复测评价探测效果。更多还原

【Abstract】 In recent years, with the continuous socio-economic development, urbanization, continuously push forward the city have been expanding in order to achieve sustainable development strategy, in addition to the development of urban roads, underground space development and utilization of subway, light rail be The history of urban development is inevitable.However, with a lot of construction of the subway, also produced a number of engin-eering problems, such as the subway shield tunnel construction caused surface subsidence. Metro Shield construction is within the rock mass, excavation and construction of the tunnel will inevitably disturbance of underground rock and soil, and destroy the original state of equilibrium, while the conversion to a new equilibrium state. With the conduct of the shield, the dense band and empty ground loss caused by the gradual upward to cause surface subs-idence in the case of lack of synchronization grouting, surface subsidence to a certain extent, will affect the safety of the ground structure and underground pipelines normal to use.Special Chengdu engineering geological conditions, water-rich sand and gravel form-ations, sand and gravel soil, gravel content, particle size, including boulders, high strength stone, sandy filling, poor bond strength between the pebbles, and therefore easier to the for-mation of surface subsidence. Metro Line1, the construction process, the resulting surface subsidence is particularly serious. Therefore, in the process of shield construction of Metro Line2, real-time identification of the disturbed zone caused by the dense band and empty, and the quality of governance evaluation is an important guarantee to ensure that the shield construction security and public safety.Ground-penetrating radar method is mainly based on high frequency electromagnetic wave propagation in the medium and the reflective properties in electrical mutation interface, a nondestructive geophysical method. Chengdu Metro Line2West Extension Line the Xipu station to Tianfu Square station around line a total of approximately24.471kilometers, is located in the downtown area of Chengdu, the flow of people, while the bottom of the mine ground-penetrating radar speed, high efficiency, non-destructive and on surrounding envir-onment affect the advantages of small, so the bottom radar Chengdu Metro Line2Shield construction strata disturbed zone.This paper studies the following aspects:1. Basic principles and data processing method of ground penetrating radar;2. Shield construction disturbance with the pre-test, impact test such as groundwater salinity of ground-penetrating radar, surface probing depth trials and tests of tunnel segments; 3. The development of specific surface and tunnel vaults detection program;4. Inductive analysis of the underground caves and dense band radar response characteristics of typical examples, and retest evaluation to detect the effect of underground caves at the grouting treatment.更多还原