Abstract Using a metro shield tunnel with a continuously jointed segment lining in soft soil as the object of analy? sis, the distribution characteristics and long-term changing law of the longitudinal deformation of a metro tunnel that has been operating for 7 years were systematically studied based on a statistical analysis of the measured elevation and settlement data of the track bed. The study results show that: 1) research on elevation data characteristics is essential to the auxiliary judgment of the longitudinal deformation and force state of the operating tunnel; 2) tunnel settlement occurred quickly at the beginning of operation; 3) as time passes, the average monthly settlement gradually decreases; 4) for the whole line, the average monthly settlement is between -2 mm and 2 mm; 5) it is approximately a linearly proportional relationship between the law of tunnel settlement development and formation compression deformation and groundwater level variations, which means the average monthly settlement of the operating tunnel decreases gradually with the rising of the groundwater level, and vice versa; 6) the longitudinal deformation curve of each running tunnel is distributed as a Gaussian function and its symmetric center is approximately the bypass passage, with the minimum elevation near the bypass and the point of inflection near the entrance and exit of the sta? tion; and 7) the curve of elevation difference per linear meter to estimate the longitudinal distribution characteristics of the staggered hoop joint is asymmetrically distributed and centered approximately around the bypass.
Abstract：
Using a metro shield tunnel with a continuously jointed segment lining in soft soil as the object of analy? sis, the distribution characteristics and long-term changing law of the longitudinal deformation of a metro tunnel that has been operating for 7 years were systematically studied based on a statistical analysis of the measured elevation and settlement data of the track bed. The study results show that: 1) research on elevation data characteristics is essential to the auxiliary judgment of the longitudinal deformation and force state of the operating tunnel; 2) tunnel settlement occurred quickly at the beginning of operation; 3) as time passes, the average monthly settlement gradually decreases; 4) for the whole line, the average monthly settlement is between -2 mm and 2 mm; 5) it is approximately a linearly proportional relationship between the law of tunnel settlement development and formation compression deformation and groundwater level variations, which means the average monthly settlement of the operating tunnel decreases gradually with the rising of the groundwater level, and vice versa; 6) the longitudinal deformation curve of each running tunnel is distributed as a Gaussian function and its symmetric center is approximately the bypass passage, with the minimum elevation near the bypass and the point of inflection near the entrance and exit of the sta? tion; and 7) the curve of elevation difference per linear meter to estimate the longitudinal distribution characteristics of the staggered hoop joint is asymmetrically distributed and centered approximately around the bypass.
LI Ming-Yu- Jiang-Ping-Yuan- Zhao-Ji-Bin- Fan-Ming-Hui- Zhou- Jie- Feng-Gao-Shun- Chen- Hong
.Analysis of the Long-Term Deformation Law and Longitudinal Distribution Characteristics of Operating Metro Shield Tunnels in Soft Soil[J] MODERN TUNNELLING TECHNOLOGY, 2016,V53(5): 25-30
2016, Vol. 53 