Method for measuring and calculating rock mass in-situ modulus

Abstract

The invention discloses a method for calculating rock mass in-situ modulus, and the method comprises the steps: building a sandstone one-dimensional deformation constitutive model according to the characteristic that the macromodulus of sandstone evolves along with the strain in a loading process or a deformation process; and fitting indoor uniaxial / triaxial compression test data to obtain undetermined parameters in the model. The influence of cracks on rock mechanical properties is quantitatively described macroscopically by adopting a damage concept, and a damage evolution model is constructed by using a common one-dimensional damage constitutive structure. The minimum value of the damage evolution model is defined as the initial damage value omega 0 of the rock mass to obtain f < 0 >, to acquire the modulus E < situ > of the rock in the in-situ state. The influence of initial damage, caused by natural or human reasons, of the rock mass on the rock mass in-situ modulus is fully considered, and the rock mass in-situ modulus calculation precision is improved. The invention can be used for effectively measuring the in-situ modulus of the rock under different confining pressure environments, is simple and easy to operate, and can be widely applied.

Description

technical field [0001] The invention relates to a method for measuring and calculating the in-situ modulus of a rock mass, belonging to the technical field of geotechnical engineering. Background technique [0002] At present, my country's economy is in a stage of rapid development, and a large number of tunnel projects, mining projects, roadway projects, etc. are under construction or proposed, and are developing towards deeper, longer and closer to existing projects. The construction of the project in progress will affect the rock mass of the existing project nearby, such as the violent disturbance caused by blasting, and even cause damage to the rock mass of the adjacent project and weaken its strength. Therefore, determining the mechanical properties of in-situ rock mass is particularly important for predicting the safety assessment of existing projects under construction. Field tests or indoor tests are usually used to calculate the physical and mechanical parameters o...

AI Technical Summary

Problems solved by technology

Field tests are generally carried out directly on site, which requires more time, energy and cost, and usually cannot obtain enough sample data; indoor tests are generally carried out by drilling cores and making standard samples for uniaxial / triaxial tests. The modulus is obtained, and then the in-situ modulus is obtained through conversion, but the damage caused by the coring process and unloading is often ignored, so that the accuracy of the in-situ modulus obtained by conversion is not high, and the evaluation accuracy of the impact of construction on the original project is reduced.

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