阅读说明：本技术 一种利用微生物灌浆置换墙体低强度砂浆的方法 (Method for replacing low-strength mortar of wall by utilizing microbial grouting ) 是由 李安起 贾强 张鑫 于 2021-09-14 设计创作，主要内容包括：本发明公开了一种利用微生物灌浆置换墙体低强度砂浆的方法,涉及墙体砂浆的置换加固领域,解决了现有墙体低强度砂浆无法更换的问题,保证了建筑原样貌,具体方案为：包括以下步骤：在墙体上下相邻两皮砖的水平砂浆缝中,剔除部分低强度砂浆,剔除的砂浆平面上呈三角形,形成先剔除区域；在先剔除区域内填筑细砂；在墙体一侧向剔除低强度砂浆的三角形区域灌注微生物灌浆液,直至灌浆液在墙体另一侧灌注孔流出；剔除后剔除区域的剩余部分低强度砂浆,并在该区域内填筑细砂,而后在该区域灌注微生物灌浆液。(The invention discloses a method for replacing low-strength mortar of a wall by utilizing microbial grouting, relates to the field of replacement and reinforcement of wall mortar, solves the problem that the existing low-strength mortar of the wall cannot be replaced, ensures the original appearance of a building, and has the following specific scheme: the method comprises the following steps: removing partial low-strength mortar from horizontal mortar joints of two adjacent bricks above and below the wall, wherein the removed mortar is triangular on the plane to form a first removal area; filling fine sand in the first removing area; pouring microorganism grouting liquid into the triangular area with low-strength mortar removed from one side of the wall until the grouting liquid flows out of a pouring hole at the other side of the wall; and removing the low-strength mortar of the rest part of the area after removing, filling fine sand in the area, and then pouring microorganism grouting liquid in the area.)

1. A method for replacing low-strength mortar of a wall by utilizing microbial grouting is characterized by comprising the following steps:

removing partial low-strength mortar from horizontal mortar joints of two adjacent bricks above and below the wall, wherein the removed mortar is triangular on the plane to form a first removal area;

filling fine sand in the first removing area;

pouring microorganism grouting liquid into the triangular area with low-strength mortar removed from one side of the wall until the grouting liquid flows out of a pouring hole at the other side of the wall;

and removing the low-strength mortar of the rest part of the area after removing, filling fine sand in the area, and then pouring microorganism grouting liquid in the area.

2. The method of claim 1, wherein the bottom edge of the first-removed area is equal to the long edge of the brick, the bottom edge of the first-removed area is located at the first side of the wall, and the top corner of the first-removed area is located at the middle of the brick at the second side of the wall.

3. The method for replacing low-strength mortar of a wall body by using microbial grouting according to claim 1 or 2, wherein the bottom edge of the post-removal area is equal to the long edge of a wall brick, the bottom edge of the post-removal area is positioned at the second side of the wall body, and the top corner of the post-removal area is positioned in the middle of the brick at the first side of the wall body.

4. The method of replacing low-strength mortar for walls according to claim 1, wherein before removing the low-strength mortar, the horizontal mortar of the adjacent bricks on the upper and lower sides of the wall is divided into a plurality of regions to be removed first and a plurality of regions to be removed later according to a triangle.

5. The method of replacing low-strength mortar in wall body by using microbial grouting according to claim 1, wherein grouting holes are reserved in three corners of the first-removed area, microbial grouting liquid is poured into the grouting holes on two sides of the wall body by using grouting equipment, and the positions of mortar layers except the grouting holes are blocked by using adhesive tapes.

6. The method for replacing low-strength mortar of a wall body by using microbial grouting according to claim 1 or 5, wherein the microbial grouting comprises a mixed solution of a calcium source solution, nutrient salts and a bacterial solution; the volume ratio of the calcium source solution to the mixed solution of the nutrient salt and the bacteria liquid is (1-3): (1-4).

7. The method for replacing low-strength mortar of a wall body by using microbial grouting according to claim 6, wherein the grouting is performed in a plurality of cycles; and a mixed solution of nutrient salt and bacterial liquid is filled in each grouting, and then a calcium source solution is filled in each grouting.

8. The method of replacing low-strength mortar for walls using microbial grouting according to claim 7, wherein the calcium source solution is repeatedly poured in several times during each grouting process.

9. The method of replacing low strength mortar of wall body by microorganism grouting as claimed in claim 7, wherein when the first and second elimination areas are grouted, after the calcium source solution is grouted, the grouting is stopped when no grouting liquid flows out from the grouting hole, and the fine sand in the grouting area is filled with calcium carbonate deposition to form a new mortar layer.

10. The method for replacing low-strength mortar of a wall body by using microbial grouting according to claim 5, wherein after the low-strength mortar of the first-removal area and the low-strength mortar of the second-removal area are replaced, grouting equipment and the plugging adhesive tape are removed.

Technical Field

The invention relates to the field of replacement and reinforcement of wall mortar, in particular to a method for replacing low-strength wall mortar by utilizing microbial grouting.

Background

The statements herein merely provide background information related to the present disclosure and may not necessarily constitute prior art.

The masonry structure is the most common structural form in the existing buildings, but as a large number of existing buildings are long-term in construction and the strength of masonry mortar is low, the seismic performance of the masonry structure can not meet the requirements of the existing specifications.

The inventor finds that the traditional seismic strengthening method of the masonry structure does not have a good wall mortar replacement method, a double (single) face reinforcing mesh method is mostly adopted, a pull rod, a constructional column and the like are additionally arranged, but the methods can not only damage the original building masonry structure to a certain degree, but also change the appearance of the original building, cannot perform seismic strengthening on the masonry structure on the premise of ensuring the appearance and mechanical properties of the original building masonry structure, and are not suitable for protective buildings with historical appearances.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a method for replacing low-strength mortar of a wall by utilizing microbial grouting.

In order to achieve the purpose, the invention is realized by the following technical scheme:

in a first aspect, the present invention provides a method for replacing low-strength mortar of a wall by using microbial grouting, comprising the following steps:

removing partial low-strength mortar from horizontal mortar joints of two adjacent bricks above and below the wall, wherein the removed mortar is triangular on the plane to form a first removal area;

filling fine sand in the first removing area;

pouring microorganism grouting liquid into the triangular area with low-strength mortar removed from one side of the wall until the grouting liquid flows out of a pouring hole at the other side of the wall;

and removing the low-strength mortar of the rest part of the area after removing, filling fine sand in the area, and then pouring microorganism grouting liquid in the area.

As a further technical scheme, the bottom edge of the area to be removed is equal to the long edge of the wall brick, the bottom edge of the area to be removed is located on the first side of the wall, and the top angle of the area to be removed is located in the middle of the brick on the second side of the wall.

As a further technical scheme, the bottom edge of the post-rejection area is equal to the long edge of the wall brick, the bottom edge of the post-rejection area is positioned on the second side of the wall, and the top angle of the post-rejection area is positioned in the middle of the brick on the first side of the wall.

As a further technical scheme, before low-strength mortar is removed, horizontal mortar of upper and lower adjacent bricks of a wall body is divided into a plurality of first removing areas and a plurality of second removing areas according to a triangle.

As a further technical scheme, grouting holes are reserved in three corners of the first-eliminating area, microbial grouting liquid is poured into the grouting holes on two sides of the wall body through grouting equipment, and the positions of the mortar layers except the grouting holes are blocked by adhesive tapes.

As a further technical scheme, the microorganism grouting liquid comprises a calcium source solution, a mixed solution of nutrient salt and bacterial liquid; the volume ratio of the calcium source solution to the mixed solution of the nutrient salt and the bacteria liquid is (1-3): (1-4).

As a further technical scheme, the grouting is carried out in multiple cycles; and a mixed solution of nutrient salt and bacterial liquid is filled in each grouting, and then a calcium source solution is filled in each grouting.

As a further technical scheme, in each grouting process, the calcium source solution is repeatedly poured for multiple times.

As a further technical scheme, when the first elimination area and the second elimination area are grouted, after the calcium source solution is poured, grouting is stopped when no grouting liquid flows out of a grouting hole, and fine sand in the grouting area is filled with calcium carbonate for deposition to form a new mortar layer.

As a further technical scheme, after the low-strength mortar in the first-removing area and the second-removing area is replaced, grouting equipment and a sealing adhesive tape are removed.

The beneficial effects of the invention are as follows:

(1) according to the invention, the triangular area is adopted to remove the low-strength mortar by stages, so that the original wall structure can not be unstably damaged, other supporting structures are not required, and the original appearance of the wall can be effectively reserved.

(2) The microbial grouting product is a liquid with low viscosity before solidification, can permeate into the deep part of a concrete crack by virtue of negative pressure, can quickly and fully fill the chiseled part of the horizontal mortar joints of two adjacent bricks, is more fully filled compared with the traditional method for directly filling mortar, effectively avoids filling the crack, and ensures the strength of the original building masonry structure.

(3) The microorganism grouting product is calcium carbonate after being cured, has the same components as concrete, has good compatibility with sand and bricks, has good bonding effect, and effectively improves the shock resistance of the wall.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the invention and not to limit the invention.

FIG. 1 is a schematic flow diagram of a method for replacing low strength mortar in a wall using microbial grouting according to one or more embodiments of the invention;

FIG. 2 is a schematic plan view of a masonry wall profile according to one or more embodiments of the present invention;

FIG. 3 is a schematic plan view of mortar distribution for a masonry wall according to one or more embodiments of the present invention;

FIG. 4 is a schematic plan view of a first mortar removal zone of a masonry wall according to one or more embodiments of the present disclosure;

FIG. 5 is a schematic illustration of fine sand filling within a culling area according to one or more embodiments of the invention;

FIG. 6 is a schematic plan view of a portion of pre-knockout grout produced calcium carbonate seal according to one or more embodiments of the present disclosure;

FIG. 7 is a schematic rear culling area mortar plan view according to one or more embodiments of the invention;

FIG. 8 is a schematic plan view of a fine sand pack in a post-culling area in accordance with one or more embodiments of the invention;

FIG. 9 is a schematic plan view of grout generated calcium carbonate in a post-culling area, according to one or more embodiments of the invention;

in the figure: the mutual spacing or size is exaggerated to show the position of each part, and the schematic diagram is only used for illustration;

wherein, 1, a boundary line; 2. low-strength mortar; 3. a reserved low strength mortar area; 4. removing areas first; 5. grouting holes; 6. a calcium source grouting pump; 7. grouting pump of bacterial liquid and nutritive salt; 8. grouting pipes; 9. a dispensing valve; 10. a valve; 11. fine sand; 12. removing calcium carbonate deposition in the area; 13. a post-rejection area; 14. and calcium carbonate deposition in the area is removed.

Detailed Description

It is to be understood that the following detailed description is exemplary and is intended to provide further explanation of the invention as claimed. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

The inventors have found that microbial induction of calcium carbonate deposits results from a complex series of biochemical reactions: some alkalophilic microorganisms are able to break down urea into NH using self-produced urease₃And CO₂The increase in the amount of ammonia formed as a result of decomposition causes an increase in the pH of the surrounding environment, causing CO to form₂In solution with CO₃ ^2-In the form of (1) if Ca is present around the bacteria²⁺The organic monolayer membrane with negative charge in the bacterial cells can continuously chelate Ca²⁺Can cause the deposition of calcium carbonate crystals, has low viscosity before solidification, can permeate into the deep part of a crack by virtue of negative pressure, has stable properties such as calcite generated by microorganism induced deposition and the like, and is combined with conventional building materialsThe composite material has good combination property, the capabilities of the repaired material such as compression resistance, acid resistance, alkali resistance, freeze-thaw cycle resistance, carbonization resistance, impermeability and the like are improved, the material cannot lose effectiveness due to aging, and the strength grade of sand consolidation by utilizing microbial grouting reaches above C30, so that the replacement of low-strength mortar of a wall body by utilizing a sand consolidation technology becomes possible.

In order to realize the replacement of the low-strength mortar of the wall body, the invention is realized by the following technical scheme:

in a typical embodiment of the present invention, as shown in fig. 1 to 9, a method for replacing low strength mortar of a wall using microbial grouting is proposed.

The wall body aimed at by the scheme is provided with a plurality of bricks from top to bottom, and the wall body is provided with a plurality of layers of bricks from front to back; horizontal mortar is arranged between the upper and lower adjacent bricks, in the scheme, one part of the horizontal mortar layer is removed, then fine sand is filled, then microbial grouting liquid is poured, the other part of the horizontal mortar layer which is not removed is removed, and the microbial grouting liquid is poured after the fine sand is filled.

Before removing the low-strength mortar, dividing the horizontal mortar of the upper and lower adjacent bricks of the wall into a plurality of first removing areas 4 and a plurality of second removing areas 13 according to a triangle.

Each area of first rejecting and the area of second rejecting are all triangular, the area of first rejecting and the area of second rejecting are arranged oppositely, the arrangement of the area of first rejecting and the area of second rejecting is to ensure that the masonry structure can not be unstable, and the original distance between the upper layer of brick and the lower layer of brick of the original wall can be ensured, thereby avoiding the damage to the original wall structure.

The triangular area for removing part of the low-strength mortar is a first removing area, and a low-strength mortar area 3 is reserved in the second removing area before construction of the second removing area.

It can be understood that the elimination area is in a triangular structure, compared with other shapes, the elimination process is simpler, the subsequent tape plugging is more convenient, and the method belongs to the optimal scheme.

Specifically, the bottom edge of the first-removing area is equal to the long edge of the wall brick, the bottom edge of the first-removing area is located on the first side of the wall, and the top angle of the first-removing area is located in the middle of the second side brick of the wall. The bottom edge of the rear rejection area is equal to the long edge of the wall brick, the bottom edge of the rear rejection area is positioned at the second side of the wall, and the top angle of the rear rejection area is positioned in the middle of the brick at the first side of the wall.

It can be understood that the first side and the second side of the wall are two side edges in the length direction of the wall respectively, and mainly aim to distinguish a first-removing region and a second-removing region, the first-removing region is at the first side in this embodiment, and in other embodiments, which side is the first side and which side mortar is removed first can be determined according to the actual construction condition.

In this embodiment, after the construction of the first-reject area is completed, the fine sand 11 is filled in the triangular area where the low-strength mortar is rejected, and the fine sand can be filled and laid by using the existing devices such as the plug plates, so long as the fine sand can be uniformly filled in the first-reject area.

Grouting holes 5 are reserved at three corners of the first removing area, and the grouting holes 5 are used for pouring microorganism grouting liquid into the first removing area filled with fine sand.

And the grouting process is that microbial grouting liquid is respectively poured into the grouting holes on two sides of the wall by using grouting equipment, wherein the microbial grouting liquid is a mixed solution of calcium source solution, nutrient salt and bacterial liquid.

Specifically, a bacterium liquid and nutrient salt grouting pump 7 is arranged on the side of the first elimination area of the wall body and is used for pouring a bacterium liquid and nutrient salt mixed solution into grouting holes on two sides of the bottom edge of the first elimination area; and arranging a calcium source grouting pump 6 at the side of the rear rejection area of the wall body, and pouring a calcium source solution into the grouting hole at the top corner of the first rejection area.

The volume ratio of the mixed solution of the bacterial liquid and the nutrient salt is (1-3): (1-4), wherein the nutrient salt solution comprises urea (CO (NH)₂)₂) A solution, the main function of which is to provide nutrients for the growth and reproduction of microorganisms; microorganisms in the bacterial liquidIs a pasteurella bacillus, and is cultured by a fermentation tank, and the components and the content of a culture medium are as follows: 20g/L of yeast extract, 10g/L of ammonium sulfate, 2g/L of sodium hydroxide (pH is adjusted to be 9) and 10umol/L of nickel chloride, wherein the culture time is set to be 20h, the temperature is set to be 30 ℃, the rotating speed of a shaking bed is 210r/min to ensure that sufficient oxygen is supplied to bacteria, the enzyme activity of the bacterial liquid is detected by an electric conductivity method after the culture is finished, and the bacterial liquid is qualified when the OD600 of the enzyme activity of the bacterial liquid is more than 1.

Grouting equipment comprises grouting pump, grouting pipe 8, distributing valve 9 and a plurality of valve 10, and the grouting pipe is connected with the grouting pump, and the distributing valve setting is in grouting pipe's grout mouth department for the solution reposition of redundant personnel in the grouting pipe through the branch road, all is equipped with the valve on each branch road of distributing valve, can realize the control of different branch roads.

Specifically, the grouting pipes led out from the branches of the distributing valve are placed near the grouting holes at the vertex angles of the triangle, the positions of other mortar layers at the positions of the grouting holes are blocked by using adhesive tapes, and the adhesive tapes are mainly used for blocking the first-rejection areas so as to prevent the poured solution from entering the second-rejection areas and mixing with the mortar layers which are not rejected in the second-rejection areas, so that the subsequent construction of the second-rejection areas is effectively guaranteed.

The invention relates to a multi-cycle grouting process, in particular to a method for grouting a concrete grouting material, wherein 1 hour before grouting, bacterial liquid and urea (CO (NH) are firstly mixed₂)₂) The solution was as follows (1-3): (1-4), connecting a grouting pipe with a grouting hole at one side of the wall, and perfusing a bacterial liquid and urea (CO (NH)₂)₂) The mixed solution of the solution is mixed until grouting liquid flows out of a grouting hole on the other side of the wall body;

after 12 hours of stop, connecting the grouting pipe at the other side of the wall body with a grouting hole, and pouring a calcium source solution until grouting liquid flows out from the grouting hole at the other side of the wall body;

after another 12 hours of rest, the calcium source solution was again perfused, and the perfusion of the calcium source solution was repeated 5 times.

The grouting process is a primary grouting circulation, when the primary grouting circulation process is finished and the stop time is 12 hours, the 2 nd grouting circulation is started, namely the grouting circulation process is repeated;

after about 3 to 4 grouting cycles, the grouting can be stopped, the grouting holes are no longer filled with grouting liquid, and at the moment, the fine sand in the grouting area is filled with calcium carbonate deposition, namely, the calcium carbonate deposition 12 in the grouting area is removed, and the deposition tightly bonds the fine sand and the bricks together to form a new mortar layer.

It is understood that the mixed solution of nutrient salt and bacteria liquid is poured in each grouting, and then the calcium source solution is poured in.

Through the multiple grouting cycles, a new mortar layer is formed in the removing area, and then the construction of the removing area can be carried out, namely like the construction of the removing area, horizontal mortar in the removing area is removed, fine sand is filled in the removing area, grouting equipment is placed on two sides of the wall, microbial grouting liquid is poured into grouting holes through the grouting equipment, calcium carbonate deposits 14 in the removing area are formed through the multiple grouting cycles, and the fine sand and bricks are tightly bonded together through the deposits to form the new mortar layer.

After all the low-strength mortar is replaced, the grouting equipment and the plugging adhesive tape are removed, and the replacement of the low-strength mortar between the upper and lower brick layers can be realized on the premise of keeping the appearance of the original wall structure.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.