Method for making internal cracks in rock samples and quantitative evaluation of grouting effect

Abstract

The invention provides a rock sample internal crack manufacturing and grouting effect quantitative evaluation method. The method comprises the steps of 1, drilling a small-diameter grouting hole in one end of a complete rock sample; 2, measuring a rock sample wave velocity Vinact by using an ultrasonic detector; 3, converting a compression load into a tensile load vertical to a loading direction through a transmission plate, indirectly stretching the rock sample, and forming a circular crack zone which is not connected with a surface in the rock sample; 4, measuring the wave velocity Vfractureof the crack-containing rock sample by using the ultrasonic detector; 5, injecting a slurry into the internal cracks of the rock sample through a grouting hole; 6, after the slurry is solidified, measuring the wave velocity Vgrouting of the grouting rock sample by using the ultrasonic detector; 7, carrying out a direct tensile test on the grouting rock sample, and recording peak stress sigma grouting and a peak strain epsilon grouting of the grouting rock sample; and 8, calculating a crack parameter, and grouting effect quantitative evaluation.

Description

technical field [0001] The invention belongs to the field of rock mechanics and engineering, and in particular relates to a method for making internal cracks in rock samples and quantitatively evaluating grouting effects. [0002] technical background [0003] Grouting is a common reinforcement method in rock engineering such as roadways / tunnels and slopes. Simply put, grouting is to inject cement-based, chemical-based grout into primary cracks (bedding, joints, faults, etc.) + secondary cracks (excavation disturbance cracks) in rock engineering through grouting equipment to repair and strengthen surrounding rock effect. [0004] The grouting effect is mainly controlled by two indicators of crack parameters and grout. Considering that the crack parameters in rock engineering change with time and space, how to quantitatively evaluate (compare) the grouting effects of different types of grout? [0005] In the rock engineering site, it is almost impossible to find two constru...

AI Technical Summary

Problems solved by technology

This involves two issues: making internal cracks in rock samples; quantitative evaluation of grouting effect

[0007] The above three methods all have fatal flaws: the first two methods are only suitable for rock-like materials and cannot be applied to natural rocks; the three methods cannot make internal cracks that are not connected to the surface

[0009] Both of the above two methods have fatal flaws: ①The former, without grouting, is only an indirect guess; Difficult to control, large discrete

Up to now, the quantitative evaluation of grouting effect is still a worldwide problem, and the industry has not yet found a simple and reliable quantitative evaluation method for grouting effect

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