The shield tunneling in deep stratum of the soft soil can produce soil arching effect on a certain degree. The degree and the later development of the arching effect are directly related to the economy and safety of the project. The development of soil arching effect in the whole process can be available through the whole measure section of soil pressure monitoring in the field for a long time, including the construction, consolidation, and creep stage. The boundary range, the attenuation rule of soil arching effect, and the variation amplitude of earth pressure can be obtained by the monitoring data of earth pressure in deep soft soil. Through the monitoring in the field, the passive soil arching effect influence range of tunneling is concentrated in the range of 1.5 times tunnel diameter in the condition of buried depth for 4 times tunnel diameter. In front of shield cutter, soil arching disturbance range is one time tunnel diameter. The value-added rate of earth pressure in the passive arching effect is 40-50% by the soil squeezing effect in front of the cutter. The earth pressure is affected by the friction force produced by the shield shell when the shield passes through the monitoring section, so the change of earth pressure in the soil arching is small. The change of the soil arching effect in the process of the grouting and slurry hardening mainly depends on the filling rate of the grouting amount to the gap between the shield and the tunnel. It can be seen from the monitoring data that the attenuation stage of the soil arching effect is mainly concentrated in the two years after the completion of the construction. The most obvious position of the attenuation effect on soil arching during consolidation and creep stage is the most obvious position of the variation of soil arching effect during tunnel construction. The spatial position of the soil arching effect corresponding to the tunneling stage and creep stage is basically the same. The ratio of soil arching effect is reduced from 45% to 25% in two years. The field test provides a certain reference value for the proportion of arching effect in the deep layer of soft soil and development rule in the whole process.
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