Method for predicting compressive strength of argillaceous siltstone

Abstract

The invention relates to a method for predicting the compressive strength of argillaceous siltstone, which comprises the following steps: Step 1: After taking out the core in the survey hole, measure the shear wave velocity V at the core in the hole in time s and P-wave velocity V p Test, and at the same time send the taken core to the laboratory for indoor core acoustic testing; Step 2: Observe the longitudinal wave velocity V of the core in the same depth interval p , V p ’ and shear wave velocity V s , V s 'Comparison in the reconnaissance hole and in the room; Step 3: Conduct a compression test on the core; Step 4: Test the mud content of the compressed rock core fragments; Step 5: Analyze the mud content and compressive strength f r Correlation of the core, while analyzing the compressive strength of the core and the shear wave velocity V s and longitudinal wave velocity V p The correlation; Step 6: Make the shear wave velocity V of the rock core respectively s , longitudinal wave velocity V p , mud content and compressive strength f r The corresponding relationship diagram; Step 7: Establish the prediction formula f 预 ;Step 8: Establish the corrected compressive strength correction formula f 修 .

Description

technical field [0001] The invention relates to the technical field of geotechnical tests, in particular to a method for predicting the compressive strength of argillaceous siltstone. Background technique [0002] At present, the compressive strength of rock in geotechnical tests is mainly drilled in the field by drilling rigs, and core samples are taken and sent to the laboratory, and the compressive strength data is obtained by rock presses. The argillaceous siltstone belongs to extremely soft rock, and its compressive strength value is between 0 and 20 MPa. The value range is not large, but the rock samples are greatly affected by water, heat, humidity and exposure during the preservation process, and will disintegrate and break , The vibration fracture during transportation also happens from time to time. Therefore, the samples need to be measured immediately after entering the laboratory, which brings a lot of trouble to the testers. Sometimes there are too many sample...

AI Technical Summary

Problems solved by technology

[0003] In addition, the core samples taken by on-site drilling rig sampling personnel are often not clearly marked, and it is not uncommon for samples to be mixed up. Some strongly weathered and broken cores cannot be sampled. The degree of coring often depends on the selection of drilling rigs and drilling tools. Staffing levels also have a big impact on sampling

So to some extent, it is difficult to accurately obtain the real compression data of a certain depth of the borehole

Unable to take samples or broken samples bring a lot of troubles to survey technicians, and the data finally submitted to survey technicians or foundation designers are often estimated based on experience, which is obviously unscientific

In particular, the cores of many key parts are often unavailable, the samples are broken, or shattered during transportation, the samples are not well packaged and damaged, and the samples are kept in the laboratory for a long time after sampling, which leads to the disintegration and fragmentation of the samples.

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