Equal energy deformation composite foundation using microorganisms to solidify aggregate and the construction method thereof

Patent metadata

Field	Value
Publication number	US-2022315882-A1
Application number	US-202117310779-A
Country	US
Kind code	A1
Filing date	May 21, 2021
Priority date	Oct 12, 2020
Publication date	Oct 6, 2022
Grant date	—

Abstract

The present invention discloses an equal energy deformation composite foundation using microorganism to solidify aggregate and a construction method thereof, the composite foundation comprises a pile body and a cushion layer, wherein the pile body is provided with several piles, the cushion layer is arranged at the top of the pile body, the pile body is connected into an integral structure through the cushion layer, and the pile body and the cushion layer are filled with aggregate solidified by microorganism. The method comprises the following steps: step 1, leveling the site; Step 2, construction preparation; Step 3, the pile driver in place; Step 4, forming a hole by hammering; Step 5, filling aggregate into the hole; Step 6, repeating the work of step 5; Step 7, forming an equal energy deformation compaction pile using microorganism to solidify aggregate; Step 8, moving to the next pile; Step 9, tamping the ground; Step 10, until the cushion is flush with the surface. Beneficial effects: using local materials, turning waste into wealth, being environmental friendly, saving project cost and conforming to the concept of green development.

First claim

1 . An equal energy deformation composite foundation using a microorganism to solidify aggregate, the composite foundation comprising: a pile body and a cushion layer, wherein a plurality of piles are arranged in the pile body, the cushion layer is arranged at a top of the pile body, the pile body is connected into a whole structure by the cushion layer, and the aggregate solidified by the microorganism is filled in the pile body and the cushion layer.

2 . The equal energy deformation composite foundation using microorganism to solidify aggregate according to claim 1 , wherein the microorganism is Bacillus pasturii.

3 . The equal energy deformation composite foundation using the microorganism to solidify aggregate according to claim 1 , wherein the aggregate is a coral aggregate or a construction waste, the coral aggregate comprises a coarse aggregate and a fine aggregate, the coarse aggregate is coral gravel, and the fine aggregate is coral sand, namely calcareous sand; the construction waste comprises a concrete block, a crushed stone, a plain soil, a metal, brick, a tile and a gypsum; after treatment of screening, rolling and crushing, a particle size of construction waste is less than or equal to 30 mm.

4 . A construction method for an equal energy deformation composite foundation using a microorganism to solidify an aggregate, the construction method comprising the steps of:
cleaning and leveling a site; construction preparation of the site including: carrying out construction setting-out and line inspection; and checking and adjusting construction equipment; putting a pile driver in place: and centering a heavy hammer of the pile driver with a center of a pile position; forming a hole by hammering including lifting a heavy hammer at a certain height to make it fall freely and impact a foundation soil to form a hole to a controlled depth; filling the aggregate into the hole, pouring a microbial solidification liquid with a same volume as the aggregate, wherein the microbial solidification liquid is composed of a bacteria liquid and a cementing liquid, lifting the heavy hammer to a certain height, and ramming a filler repeatedly; ramming under the an action of standard ramming energy, wherein a last penetration amount of the heavy hammer is measured to a design requirement, and when a measurement is no greater than the design requirement, the filling the aggregate into the hole is repeated; repeating the step of filling the aggregate into the hole and ramming under the action of standard ramming energy, then ramming and filling the hole to the ground, and forming an energy deformation compaction pile using the microorganism to solidify the aggregate in the foundation; after one pile is formed, the construction equipment is moved to thea next pile; after a plurality of piles are formed, a ground of the site is tamped by using a plate compactor; back-filling a layer of aggregate and microbial solidification liquid with a same volume as an aggregate on the tamped ground, a back-filling elevation is higher than a ground surface by more than 0.2 m, then lifting the plate compactor to a certain height, and ramming the aggregate after microbial solidification on the ground repeatedly until the aggregate is flush with the ground surface.

5 . The construction method of according to claim 4 , wherein the aggregate is a coral aggregate or a construction waste, the coral aggregate comprises a coarse aggregate and a fine aggregate, the coarse aggregate is coral gravel, and the tine aggregate is coral sand; the construction waste comprises a concrete block, a crushed stone, a plain soil, a metal, brick, a tile and a gypsum; after a treatment of screening, rolling and crushing, the particle size of construction waste is less than or equal to 30 mm.

6 . The construction method according to claim 4 , wherein the microorganism is Bacillus pasturii and a microorganism solution is obtained by an indoor sterile culture, centrifugal concentration, low temperature transportation and an on-site expanded culture, the construction method further comprises the steps of:
putting a prepared nutrient solution comprising an indoor culture, where every liter of a culture medium contains tryptone 15.0 g, Soybean peptone 5.0 g, sodium chloride 5.0 g in an autoclave, autoclaving the indoor culture at 121° C. for 20 minutes, and then cool it the indoor culture down in a sterile operation table; in order to avoid the a decomposition of urea, 20 g of a urea is added into the a bottle when a temperature drops to room temperature, and a pH is adjusted to 7.3; after microbial inoculation, the indoor culture is incubated at constantly 30° C. with oscillation for 24 hours; centrifugal concentration follows comprising: separating cultured microorganisms with a high-speed centrifuge to get the microorganisms, a temperature of a centrifugal chamber is 4° C., a rotating speed is 4000 rpm, and a duration is 15 min; after centrifugation, the a supernatant is removed, and the a precipitate is dissolved in fresh culture solution, a volume of the fresh culture solution is 1/10 of an original volume, that is, a 10 L microorganism solution is concentrated into a 1 L, and the concentrated microorganisms are filled into a plastic water bag and stored at 4° C.; low-temperature transportation ensues whereby the concentrated microorganisms are transported to the a site in an incubator, and ice bags are placed in the incubator to maintain a set low temperature in the incubator during transportation, and to ensure a rapid completion of the low temperature transportation; after the microorganisms are transported to the site, they are immediately put into a refrigerator and stored at 4° C.; on-site expanded culture follows whereby the culture medium used for expanded culture comprises: industrial soybean peptone 25 g/L, urea 10 g/L, MnSO 4 12 mg/L, NiCl.6H 2 O 24 mg/L; the a pH value of the culture medium is adjusted to 9.0-10.0 with NaOH, and a culture time is 12 h; after the a culture is formed, a bacterial activity was tested by conductivity; the cultured microorganisms are diluted with a cementing solution which is 0.9% NaCl solution, and immediately used for on-site foundation reinforcement after dilution; a dilution ratio is 2:1; or the solution is diluted with seawater, and the dilution ratio was 3:1.

7 . The construction method according to claim 4 , wherein the heavy hammer has a diameter of 200 mm-600 mm, a length of 1 m-5 m and a weight of 1.5-3.5 tons, the plate compactor is a 15-ton rammer composed of steel plates, a bottom surface of the rammer is round, the a diameter of a bottom of the hammer is 2 m, and two exhaust holes with a diameter of 300 mm are arranged in the rammer.

Assignees

• Univ Hainan

Inventors

• Hu Jun
• Zeng Hui
• Zeng Dongling
• Wang Zhixin
• Jia Lin

Classifications

• C12N1/20 Primary

  Bacteria; Culture media therefor · CPC title

• C12R2001/07

  Bacillus · CPC title

• E02D5/44

  with enlarged footing or enlargements at the bottom of the pile · CPC title

• C09K17/42

  Inorganic compounds mixed with organic active ingredients, e.g. accelerators · CPC title

• E02D3/08 Primary

  by inserting stones or lost bodies, e.g. compaction piles (sand drains for soil compaction E02D3/10; stressing soil while forming foundations E02D27/28) · CPC title