Preparation method of columnar jointing basalt undisturbed rock core

Abstract

The invention provides a preparation method of a columnar jointing basalt undisturbed rock core. The preparation method comprises the following steps that (1) an area where columnar joints and underground water are developed at the same time is selected, and a sampling hole is excavated; (2) freezing construction is carried out; (3) sampling is carried out; (4) chemical erosion is carried out; and(5) the rock core is prepared. According to the preparation method, composition components and high-temperature sensitivity of basalt are fully utilized, a freezing method is adopted to ensure that alarge-scale columnar joint rock mass is obtained, and the internal initial structural features are effectively retained; and meanwhile, the joint surface is weakened by adopting a chemical method instead of a physical method, so that disturbance damage to the rock mass is avoided. According to the preparation method o the columnar jointing basalt undisturbed rock core, impact disturbance on the rock core can be effectively reduced, and the undisturbed original rock core is guaranteed to be obtained to the maximum degree.

Description

technical field [0001] The invention relates to geotechnical engineering for the construction of columnar joint basalt areas, including underground caverns, slopes, tunnels (roads), dam foundations, etc., and can be applied to water conservancy, hydropower, transportation, mines, nuclear waste storage, underground laboratories, etc. The field of geotechnical engineering with higher requirements for rock conditions. Background technique [0002] Basalt has the characteristics of hard, relatively complete, strong weathering resistance and high strength. However, columnar joints are commonly developed in basalt. As a special structural rock mass, the columnar jointed rock mass exhibits typical anisotropy, discontinuity and heterogeneity in its mechanical behavior due to the existence of the columnar joint structure, which leads to a decrease in the quality of the rock mass and seriously affects Design and construction of geotechnical engineering. [0003] Columnar joint stru...

AI Technical Summary

Problems solved by technology

However, due to the existence of columnar joints, it is difficult to obtain a complete basalt core on site. Even if it is obtained, it contains a large number of joint fissures, which cannot truly reflect the true mechanical properties of basalt. Therefore, obtaining the original core of columnar jointed basalt reveals its True mechanical properties, with high practical and engineering application value

[0006] Due to the cutting effect of columnar joints, the cross-section of basalt columns is usually a regular polygonal long column, such as square, pentagonal, and hexagonal prisms. Due to the influence of physical effects such as processing and cutting, the success rate of the processed core is poor, and it is severely disturbed, which cannot reflect the real mechanical properties of the original rock sample.

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