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在多圈管冻结条件下冻结管受力变形规律的课题研究过程中,首先针对未开挖时冻结管的各向应力应变变化规律,以相似理论为基础开展物理模拟试验,得出结论:未开挖阶段的冻结管变形在冻结前期基本完成;黏土层中冻结管应变量比砂土层大;黏土层中冻结管最大拉应力为97.7MPa,最大压应力为161.5MPa,弯曲应力为轴向应力的1.7倍,最大弯曲应力达到冻结管屈服荷载的0.62倍,而砂土层中均很小。为改善冻结管的受力性能,减少开挖前冻结管储存的应变能,降低后期开挖时候冻结管的破坏率提供了实验依据。
In the process of the research on the law of stress and strain of frozen tubes under the condition of multi-ring tube freezing, firstly, according to the regularity of stress and strain changes of the frozen tubes during the un-excavation, physical simulation tests based on the similar theory were conducted, and the conclusion was drawn: The deformation of the frozen pipe in the excavation stage is basically completed in the pre-freezing period. The strain of the frozen pipe in the clay layer is larger than that in the sand layer. The maximum tensile stress of the frozen pipe in the clay layer is 97.7 MPa, the maximum compressive stress is 161.5 MPa, and the bending stress is axial 1.7 times the stress, the maximum bending stress reaches 0.62 times the yield stress of the frozen pipe, while the sand layer is very small. In order to improve the mechanical properties of the frozen pipe, reduce the strain energy of the frozen pipe before excavation, and reduce the destruction rate of the frozen pipe during the later excavation, the experimental evidence is provided.