【作者】 王伟；

【导师】 周小平； 王方汉；

【作者基本信息】 重庆大学 ， 建筑与土木工程（专业学位）， 2015， 硕士

【摘要】 高地温、高地应力、复杂的地质环境以及恶劣的气候条件等一直是偏远地区隧道工程建设的重点和难点问题,特别是近年来基础建设向偏远地区的迅猛发展使我们不得不正视这些问题,采取正确的方法解决这些问题已经迫在眉睫。高黎贡山独龙江公路隧道地处高海拔寒冷地区,不仅仅有复杂的地质条件和恶劣的气候条件,而且隧道总长达到6680m,最大埋深约为990m,属于大长深埋隧道。高地温和高地应力是隧道设计和施工的重点问题,因此本文以高黎贡山独龙江公路隧道工程为背景,分析了隧道的初始温度场、初始应力场以及隧道开挖过程中的温度应力耦合作用对隧道围岩的影响。①本文对隧道场地进行初始温度场分析,得到了隧道场地初始温度场的分布,结果表明隧道场地的变温带埋深在30m左右,隧道进口端桩号K0+270到K0+341之间和出口端桩号K6+843到K6+950之间的隧道区域属于变温带范围内。隧道开挖之前,隧道沿线的温度最大可达18.93℃,最低可达-4.63℃。②本文采用现场试验和数值模拟的方法对隧道场地进行了地应力分析,其中采用现场空心包体应力解除法和声发射法测量了隧道桩号K1+585和桩号K6+003的地应力,采用Ansys软件分析得到了隧道场地的自重应力场分布,对比结果可知隧道场地大部分区域的水平方向的地应力比竖直方向的地应力大,且构造应力在地应力中占有很大的比重。③本文以隧道场地温度场、应力场分析的结果作为边界条件对隧道开挖过程中的温度应力耦合场进行了分析,从耦合分析结果可以看出:隧道开挖后冷空气对隧道围岩温度、应力的横向影响主要表现在距离隧道一倍断面尺寸范围内,在这段范围内隧道围岩温度、应力变化最为明显并且呈现出较强的非线性,距离隧道2-3倍隧道尺寸范围以外的围岩温度、应力基本收敛到围岩的初始温度和初始应力;从纵向影响来看,隧道沿线中部围岩的温度、应力受到冷空气的影响最大,向两端逐渐减小,对隧道围岩的温度最大影响超过13.5℃,对隧道围岩最小主应力、中间主应力、最大主应力最大影响分别为3.30MPa、4.09MPa、1.74MPa。④考虑到实际工程的应用,本文还以年最低气温作为对流荷载温度对隧道开挖进行温度应力耦合场分析作为包络设计,根据计算结果建议隧道施工过程中应特别注意对流荷载对隧道中部围岩应力的影响,而且应该注意空气对流荷载对隧道围岩应力的影响是一个相对较长的时间过程需要在施工过程中长期监测,即便是在隧道运营过程中仍然需要考虑温度变化对隧道围岩应力的变化或者温度对衬砌产生的冻胀应力。更多还原

【Abstract】 High temperature, high ground stress and complicated geological conditions, with severe weather conditions and other labels have always been the focus and difficult issues of tunnel construction in remote areas, especially in recent years, the rapid development of infrastructure in those areas forces us to face these problems, which needs to be solved imminently.Located in high altitude and cold regions, Gaoligong mountain dulongjiang highway tunnel has not only complex geological and severe weather conditions, but also is a tunnel with a total length of 6680 m, maximum depth about 990 m, which belongs to long and deep tunnel. High temperature and high stress are the key problems in the design and construction of the tunnel, under the Gaoligong mountain dulongjiang highway tunnel construction project, this paper analyzed the initial temperature field, initial stress field, and the influence of coupling action of temperature and stress to the surrounding rock in the tunnel excavation process.①In this paper, initial temperature field of the tunnel site has been analyzed and the initial temperature distribution has been gat. The distribution results of the tunnel site’s initial temperature showed that the variable temperature zone of the tunnel site is located about 30 m deep, and the variable temperature zone ranges between stake number K0+270 and K0+341 near tunnel inlet, between stake number K6+843 and K6+950 near outlet port. Before excavation, the maximum temperature of surrounding rock along the tunnel can be 18.93 degree and the minimum temperatures can be-4.63 degree.②In this paper, in-situ stress field of the tunnel site has been analyzed by using the method of site test and numerical simulation. The In-situ stress of tunnel stake number K1+585 and K6+003 have been tested by hollow inclusion stress-relief method and sound emission method. The site’s weight stress field distribution has been analyzed through the finite element software named Ansys. The compared results shows that most of the tunnel region’s horizontal stress is much bigger than the vertical stress, and the constructed stress took a large percentage in the whole in-situ stress.③Take the results of the tunnel site’s temperature field analysis and stress field analysis as border condition, this paper analyzed the temperature and stress coupled field in the excavation process, from the results we can see that the main effect of cold air to the tunnel surrounding rock’s temperature and stress lies within the range of one time section size of the tunnel, within which the tunnel surrounding rock’s temperature and stress changes most obviously in a strong nonlinear trend, while those with 2-3 times beyond the tunnel range basically converges to the initial temperature and initial in-situ stress of the surrounding rock. From the longitudinal impact point of view, the surrounding rock’s temperature and stress of the tunnel’s central part is affected most by cold air, which decreases to both ends. The maximum affected temperature of the surrounding rock is more than 13.5 degree, and its maximum effect on the minimum principal stress, intermediate principal stress and maximum principal stress is 3.30 MPa, 4.09 MPa, 1.74 MPa respectively.④Considering the actual engineering application, this paper also take yearly minimum temperatures as convection load temperature, then analyze the temperature and stress coupled field in the excavation process. According to the calculation results, we recommend that special attention should be paid to convection load temperature’s affect to the central part of surrounding rock’s stress, and we should also note that this affect is a relatively long time process, which needs long-term monitoring in construction process, even in the process of tunnel operation, the effect of temperature change to tunnel surrounding rock stress’ s change should be considered, so does the temperature influence to lining’s frost-heave stress.更多还原