Surrounding rock creep rupture warning method applied in soft rock cavern warning system

Abstract

The invention discloses a surrounding rock creep rupture warning method applied in a soft rock cavern warning system. The method is characterized by comprising following steps: (1) reading the stress [sigma] and the strain [epsilon] of surrounding rock in a soft rock cavern (represented as the drawing 1) through a sensor; (2) reading the pre-stored data of a triaxial compression test and a triaxial creep test of a rock sample of the soft rock cavern in which the soft rock cavern warning system is arranged for obtaining physical and mechanical parameters of the soft rock, including: bonding force c, internal friction angle [phi], and Poisson ratio [mu] and stress-strain curve data of a whole triaxial creep process under any stress state being higher than long-period strength; and (3) combining the test curve, obtained through the test, of the whole triaxial creep process under the stress state with the physical and mechanical parameters obtained in the step (2).

Description

technical field [0001] The invention relates to a surrounding rock creep damage early warning method applied to a soft rock cave early warning system. This technology mainly establishes the soft rock creep constitutive equation based on the internal energy theory, calculates and predicts the value of soft rock accelerated creep, the time of occurrence and the whole process of creep, provides guidance for tunnel safety maintenance, and combines the actual situation The simplified equation proposed can be easily understood, grasped and flexibly applied by the design personnel and engineering technicians engaged in the field of underground engineering. The proposal of this technology can provide more accurate calculation and prediction for the moment of creep failure and accelerated creep failure of surrounding rock during the excavation of soft rock caverns, coal excavation roadways, goafs and their operation, making up for the standard blank. It belongs to the field of resear...

AI Technical Summary

Problems solved by technology

[0003] It is the most commonly used and most effective method to describe and predict the creep process by establishing a reasonable constitutive model. The Nishihara model is currently the most widely used creep constitutive model, but it cannot simulate the failure stage of accelerated creep. In the past few years, many scholars began to propose a modified Nishihara model to increase the simulation of the accelerated creep stage.

However, there are still controversies about how to distinguish and simulate the creep acceleration stage. At present, most of the formulas obtained are empirical formulas, which cannot reflect the essential characteristics of soft rock. The theoretical research is not enough, and some even require many experiments to obtain their constitutive formulas. hard to promote

Therefore, in actual underground engineering, it is difficult to predict the moment of accelerated creep failure of soft rock

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