| The tunnel lining is an important part of the tunnel structure. Many tunnel diseases has problem with the tunnel lining damage. The domestic and foreign scholars has caused wide public concern on the causes, mechanism and the influence of actual engineering of the damage of tunnel lining. At present, the influence of the tunnel excavation and rock creep to tunnel lining has made some progress. Reinforced concrete materials to the plastic damage theory also have some researches. But, on the condition of temporal and spatial effects, the research on the plastic damage characteristics is few. I am on the basis of previous studies, do the research with the way of the theoretical analysis and the simulation into the plastic damage theory on the condition of temporal and spatial effects. The paper mainly research content and the results are as follows:1. In order to simulate tunnel lining damage behavior completely and accurately, this paper use ABAQUS finite element analysis software to simulate the physical process of tunnel construction, and based on the powerful analysis function of ABAQUS I put forward a new method to equilibration ground stress. Through using this method to equilibration ground stress, comparing common calculation method, this method more simple and easier to convergence:In the static loading process adding a instant gravitational field, checking Automatic in Incrementation options, then in the calculation process analysis program will automatic balance ground stress. I a simple model experiment to text this method, results show that the initial displacement is in10-5～10-6m order of magnitude.2. To simulate the surrounding rock creep, I suggest to, in the creep calculation, use10-1～10-3order of magnitude in the initial incremental steps (Increment size:Initial) and use10-4～10-6order of magnitude in the Minimum incremental steps (Increment size:Minmum). Creep strain error tolerance can be set10-4～10-6order of magnitude, and this tolerance can be adjusted according to the specific calculation.3. Through analyzing the tunnel lining damage simulation result, study the rule of tunnel lining damage caused and development mode. The tunnel lining damage first produced in a bit, namely initial damage. Then, due to the initial damage grew, damage transference from point to surface, at last form a surface damage.4. In reinforced concrete lining structure, damage is produced by two kinds of force function together, stretched and compressed. According to the analysis of the simulation results, tunnel lining damage is mainly caused by stretching function; compression function to the lining structure damage plays the secondary role, and this is the same with the result of analysis result of lining structure.5. The damage growth of different points in the tunnel lining performance a smooth curve. Its initial damage is instantaneous generation; the specific performance is that the initial stage slope is very big in damage curve. And once its damage produced, the damage grows very fast. When damage develop to a certain, the growth of the damage gradually slow, finally the growth of the damage be more stable.6. Study found the tunnel lining’s mode of stress and the damage. The tunnel lining stress concentration section show cricoid distribution, circular center stress relatively concentrated, stress value is higher; deviating from the circular center, stress value gradually decrease. Circular stress almost uniform develops along the tunnel deep direction. And damage caused position is the same with stress concentration position, so they also has similar distribution.This paper was subsidized by Natural Science Foundation of China project (51078000;50708056), Natural Science Foundation of Shandong Province project (ZR2011EEM012)and outstanding youth training project of Shandong University Independent Innovation Fundation. |
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