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In order to explore the deformation characteristics of layered slate tunnels under different dip angles of rock formations, a numerical simulation research method for optimization of large deformation control parameters of layered slate tunnels is proposed. The plane deviation, plane deformation, and DP parameters of the structure are obtained through the calculation mode. When studying the effect of overlapping rock masses on the stability of thick tunnels, the incidence angle of the rock structure is assumed to be zero. The estimated thicknesses of the dolomite limestone surrounding the tunnel are 0.3 m, 0.4 m, 0.5 m, 0.6 m, 0.7 m, 0.8 m, and 0.9 m, respectively. Select the vertical displacement to be analyzed as the result of the calculation. In order to study the influence of the structural slope on the tunnel stability, the thickness of the rock layer was 0.6 m, and the structural slopes of 5°, 15°, 30°, 45°, 60°, 75°, and 85° were used for simulation calculations. During on-site construction, focus on monitoring the tunnel section deformation before the secondary lining construction. Every 10-20 m, when the surrounding rock changes, the observation section of the enclosure convergence and vault settlement is arranged, and the peripheral displacement rate and the vault settlement rate are calculated according to the observed deformation. The results show that the vertical displacement of the top of the tunnel is generally in a “V” shape, that is, the maximum settlement in the tunnel; when the layer thickness is 0.3 m, the maximum vertical displacement of the rock layer is 7.2 mm, and the total settlement in the lining support tunnel is 8.23 mm. When the layer thickness is 0.9 m, the vertical displacement of the rock layer is 5.14 mm, and the total settlement in the lining support tunnel is 5.22 mm2; when the layer thickness was changed from 0.9 m to 0.3 m, the maximum vertical displacement of the rock layer increased by 140%, and the settlement at the vault increased by 158%. At this time, the focus of tunnel support is on both sides of the lining structure and the vault with large vertical settlement. The phenomenon that the section of YK51+032 first decreases and then increases due to the sudden appearance of mud in the surrounding YK51+040, resulting in increased short-term deformation. Only the ZK49+356 section at the entrance of the left line has a large deformation due to the thin overlying stratum, and other sections are relatively consistent, indicating the reliability of the calculation results.

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Abstract. In this paper, people mainly take three two-dimensional arrays State, Energy and Ori (Ori is the positive integer of max 1 Ori Ori ≤ ≤ ) to perform the molecular states and build models. According to the simulation results of molecular automaton, people have a research on the change and distribution of the grain diameter and the number of side during the process of static recrystallization, and conclude as follows, the relationship between the disappearing rate of individual deformation grain and the growth rate of individual recrystallization grain is characterized by randomness during the whole recrystallization process; the more the deformation, the smaller the mean diameter of grain is, at the finished moment of recrystallization; the grain diameters are not homogeneous during the static recrystallization process and at the finished moment of static recrystallization. ForewordIn recent years, it has been the hot spot of the research to simulate the microstructure evolution by molecular automaton. Since Hesselbarth [1] firstly simulated the recrystallization in two dimensional condition by molecular automaton in 1991, the molecular automaton model of recrystallization has been developed rapidly. However, the effect of the plastic deformation before the static recrystallization on grain forms has not been considered in the former models, and in fact, certain deformation is the essential requirement of the static recrystallization. Therefore, based on the parent phase structure of the equiaxed grains, the author can get the corresponding deformation structure through mesh mapping. On the basis of the above research, the author can build the static recrystallization model, lay emphasis on the analysis of the change rule of grain sizes, the distribution of grains diameter and the number of sides, and make a further understanding on the static recrystallization process. The building of molecular automaton modelIn this paper, people mainly take three two-dimensional arrays State, Energy and Ori (Ori is the positive integer of max 1 Ori Ori ≤ ≤ ) to illustrate the molecular states in the research models. State can record whether the molecule can be recrystallized, and the result "0" means the molecule has a deformed structure, "1" means the molecule forms the recrystallization core, and "2" means the molecule can form recrystallization through core growth. Energy records the storage energy of molecule, which can be taken as the driving force of molecular recrystallization. Ori illustrates the molecular motion orientation. The molecules with the same orientation can form a grain, while the grains with different orientation can form natural grain boundary. The initial grain orientation value Ori can be obtained after the different effects of the equiaxed grains deformation e. During the recrystallization process, with the extending of the time step, the deformed grains can be swallowed by the new-formed recrystallization core, and at the same time, three state variables of the molecule has the corresponding ...