Testing device for microorganism-reinforced sand and use method of testing device

Abstract

The invention discloses a testing device for microorganism-reinforced sand and a use method of the testing device. A sand reinforcement testing device main body structure is composed of an equipment body and a sand mold, wherein the equipment body comprises an upper cover plate, a plexiglass column tube and a lower cover plate sequentially arranged from top to bottom; the upper cover plate and the lower cover plate are bonded with the plexiglass column tube to form a closed space; an upper gravel layer is arranged on one side of the upper part of the closed space close to the upper cover plate; an upper filter plate is arranged below the upper gravel layer; the upper filter plate is embedded in the plexiglass column tube; a lower gravel layer is arranged on one side of the lower part of the closed space close to the lower cover plate; a lower filter plate is arranged above the lower gravel layer; the lower filter plate is embedded in the plexiglass column tube; the sand mold is disc-shaped; and the sand mold is provided with a plurality of circular holes for placing of sand samples. The invention provides the testing device for microorganism-reinforced sand and the use method of the testing device; and the testing device has the advantages of simple structure, relatively high uniformity of cured samples, relatively good curing effect, high utilization rate of bacterial liquid and nutrient solution, and low cost.

Description

technical field [0001] The invention belongs to the field of geotechnical engineering, and in particular relates to a test device and a use method for strengthening sand and soil, in particular to a test device and a use method for strengthening sand and soil with microorganisms. Background technique [0002] Microbial grouting reinforcement technology is that under certain artificial environment and nutritional conditions, the metabolism of some non-toxic natural microorganisms in rock and soil can significantly precipitate a variety of mineral crystals, such as: carbonates, phosphates, oxides, silica and cellular External polymers, etc., making it possible to modify and solidify soft sandy soil in situ. This technology transmits microbial cells and nutrient salts to the loose sandy soil foundation at low pressure, and finally rapidly precipitates calcium carbonate gel crystals in the sandy soil pores to improve the mechanical properties of the soil. Microbial grouting soi...

AI Technical Summary

Problems solved by technology

[0005] 2. Most of the reaction generators use a single long tube or a plexiglass column

Although these test methods have achieved certain results, the sand pores near the water inlet are easily blocked by the generated calcium carbonate crystals during the experiment, which causes uneven distribution of bacteria and calcium carbonate in the sand sample;

[0006] 3. It is difficult to take out the sand sample from the reactor, and the sample can only be taken out by cutting the reactor, which adds trouble to the subsequent sample test; in addition, the use of water pumps and syringes causes the bacterial solution to be injected under a certain pressure, Although it can make it penetrate into the soil better, it will also cause a part of the bacterial solution and nutrient solution to be lost from the water outlet, reducing the utilization rate of urea and calcium chloride

[0007] Therefore, the existing experimental equipment for strengthening sandy soil faces the problems of uneven distribution of bacterial solution and nutrient solution in sandy soil samples, easy loss, low utilization rate, poor sandy soil solidification effect and non-reusable sandy soil reactor. Therefore, in order to improve the uniformity of solidified samples, improve the solidified effect, increase the utilization rate, and reduce the cost, designing a new experimental device for microbial grouting and solidified sand has extremely important scientific and practical significance, and has high research value

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