Research On The Mechanical Behaviors Of Masonry Building Induced By Shield Tunneling Construction

The problem that the masonry buildings were affected by shield tunneling construction has been always lain in the subway construction, and it is also very important in the urban environment geotechnical issue. Research on this subject has important theoretical and practical value. In this paper, the method of measuring and analysis for real project is adopted, based on the large number of measured and testing data in a certain soft soil subway construction of Hangzhou. A study was made on the settlement feature of the bottom and the roof of the masonry structure. Its main contents is the mathematical expression for the building planar settlement curved surface, the facade settlement curve, the distortion calculations for the building bottom plane, the three-dimensional deformation feature and the finite element simulation.Based on the measured data, two situations are considered. That is the shield tunneling below the building and the shield tunneling passing through the bottom side of the building. For the cases of single-line and double-line, the settlement variation at the bottom of the building is studied for five stages, that is, before the shield tunneling reaching, shield being reached, shield passing through, shield tail passing through, and subsequent settlement. Simultaneously, the settlement difference between the building facades and the settlement distribution feature along the facade of the building are compared.Based on arrangement of the measured data, considering two cases of single-line and double-line, the variation law for the roof settlement of the building is studied for five stages, that is, before the shield tunneling reaching, shield being reached, shield passing through, shield tail passing through, and subsequent settlement. The settlement differences and similarities between the roof and the bottom of building are compared, and the settlement distribution feature along the facade of the building is analyzed.On the basis of the settlement studies for the roof and bottom of the building, according to the spatial location of the building and the tunnel, a deep study is made on the surface at the bottom of the building after settlement and the pattern of the facade settlement curve. And the corresponding mathematical formulas are given for the pattern of settlement and the planar distortion at the bottom of the building. Relying on practical engineering, an analysis is made for the distortion of the building in the settlement process.According to two cases of single-line and double-line, the engineering test was firstly carried out for the three-dimensional deformation of the building affected by the construction of the shield tunneling. The three-dimensional deformation feature of the building caused by the tunnel construction is studied based on the field test data. And overall, some common characteristics of the three-dimensional deformation in the building are extracted.The three-dimensional finite element method is used to simulate the whole process of the masonry structure affected by the shield tunneling construction. The distribution pattern is obtained for the settlement and stress of the building. At the same time, the paper also gives the distribution law of deformation in the ground, and it is verified that the existence of the building has changed the displacement distribution in the soil around the tunnel. Based on a large number of numerical calculations, the factors of tunnel axis angle relative to the building, degree of tunnel eccentric, tunnel central buried depth, number of building floor and the length of the house are discussed.