CN111779045A - A kind of foundation reinforcement rectification method - Google Patents

Abstract

The invention relates to the technical field of foundation construction, and discloses a foundation reinforcement deviation rectifying method, which comprises the following steps: implanting anchor rod reinforcing steel bars around the first pile hole, constructing an anchor rod static pressure steel pipe pile, repeatedly extruding and grouting deep soil through the steel pipe pile, installing a pressurizing assembly and temporarily locking the steel pipe pile after grouting is finished; and (2) arranging a second pile hole on the foundation ground to be constructed, inserting a grouting steel pipe, locally and directionally reinforcing the shallow soil body by using the grouting steel pipe in a repeated grouting mode, monitoring the pressure value of the steel pipe pile in the grouting process, and gradually repressing the steel pipe pile through a pressurizing assembly so as to realize slow reinforcement lifting of a subsided soil layer and foundation rectification. The method slowly reinforces and lifts the settled soil layer by repeatedly and multi-point grouting of deep and shallow soil bodies and gradual repression of the steel pipe piles, performs directional deviation rectification on the foundation, can effectively reduce or eliminate the generated uneven settlement and the inclination of the whole building, and realizes the combination of reinforcement and deviation rectification.

Description

A kind of foundation reinforcement rectification method

technical field

The invention relates to the technical field of foundation construction, in particular to a method for rectifying deviation of foundation reinforcement.

Background technique

At present, there are many methods for strengthening the foundation of building foundations, including the pile foundation underpinning method, the root pile method, the base grouting method, etc., and mature design and construction methods have been formed, but the above methods can only strengthen the strength and stiffness of the foundation. Controlling the settlement after foundation construction cannot effectively reduce the difference in settlement between the piles, and cannot orient and rectify the overall or local inclination of the building that has occurred so that it can be reset to its original position to meet the requirements of national standards. Especially when limited by the construction site conditions and the weak strength of the original foundation, or when the bearing capacity of the soil layer at the bottom of the natural foundation is low, the reinforcement effect is often difficult to achieve the expected goal, such as using large-diameter bored piles or artificial digging. There are also certain safety risks in the construction of hole piles. Construction next to the old foundation is easy to further disturb the base soil and aggravate the settlement of the foundation.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is: how to realize the directional reinforcement and rectification of the subsidence foundation.

In order to solve the above-mentioned technical problems, the present invention provides a foundation reinforcement and deviation correction method, which includes the following steps: opening a first pile hole on the ground of the foundation to be constructed and extending to the deep soil body, and implanting around the first pile hole Anchor bar;

The foundation is used as a reaction force platform, and the steel pipe pile is pressed into the first pile hole by the anchor rod static pressure construction method;

The configured grouting liquid is squeezed and grouted through the grouting outlet of the steel pipe pile, and the deep soil body is compacted and reinforced by the repeated grouting method of "grouting-cleaning-grouting";

After the grouting is completed, the pressurized component is fixed by the anchor bar, and the steel pipe pile is temporarily locked by the pressurized component;

A plurality of second pile holes are opened on the ground of the foundation to be constructed or on the ground between two foundations and extended to the shallow soil body, grouting steel pipes are inserted into each of the second pile holes, and the grouting liquid passes through the The grouting steel pipe is squeezed and grouted, and local directional reinforcement is carried out to the shallow soil body in the same repeated grouting method, so that the settled soil layer below the foundation is lifted upward and rectified;

During the grouting process of the grouting steel pipe, the pressure change value of the steel pipe pile is obtained, and it is judged whether the pressure change value of the steel pipe pile exceeds a preset value. Compensate and pressurize the steel pipe pile to ensure the bearing capacity of the steel pipe pile;

After the reinforcement and deviation correction are completed, the pressurizing assembly is removed, concrete is poured into the steel pipe pile, and the steel pipe pile, the grouting steel pipe and the foundation are fixed as a whole by pouring concrete foundation beams.

As a preferred solution, in the step of extruding and grouting the configured grouting liquid through the grouting outlet of the steel pipe pile, it also includes:

A first grouting pipe is welded in the steel pipe pile, a second grouting pipe is inserted into the first grouting pipe and extends to the grouting outlet, and the grouting liquid passes through the second grouting Tubes are squeeze grouted.

As a preferred solution, in the step of pressing the steel pipe pile into the first pile hole by the anchor rod static pressure construction method, it also includes:

The piling pressure and verticality of the steel pipe piles are detected to maintain the vertical pressure of the steel pipe piles, and the piling pressure acting on the steel pipe piles does not exceed the maximum piling pressure.

As a preferred solution, in the step of fixing the pressurized component by the anchor rod reinforcement, and using the pressurized component to temporarily lock the steel pipe pile, the specific steps are:

The first pile pressing block of the compression assembly is fixed on the ground of the foundation through the anchor rod reinforcement, and the second pile driving block of the compression assembly is fixed to the first pile driving block through the anchor rod reinforcement bar. Above the pile pressing block, a jack is arranged between the first pile pressing block and the second pile pressing block, and the jack is used to apply prestress to the steel pipe pile.

As a preferred solution, the anchor bar is provided with a nut for adjusting the positions of the first pile pressing block and the second pile pressing block.

As a preferred solution, the grouting solution is configured by cement slurry, water glass and liquid water, and the volume ratio of the cement slurry, the water glass and the liquid water is 1.0-1.5:1:2-3 in sequence. .

As a preferred solution, the opening direction of each of the second pile holes is vertical or oblique, and the ends of each of the second pile holes face the steel pipe pile.

As a preferred solution, the grouting liquid is squeezed and grouted through the grouting steel pipe, and local directional reinforcement is performed on the shallow soil in the same repeated grouting method, so that the settled soil layer below the foundation is lifted upwards. And the steps of rectification are as follows:

Divide the configured grouting liquid into multiple groups, and carry out the repeated extrusion grouting of "grouting-cleaning-grouting" through the grouting steel pipe of each group, and grouting multiple parts of the settled soil layer. Several times of directional reinforcement are carried out at the location, so that the settled soil layer gradually rises upward and tends to a stable state, wherein, different grouting steel pipes use the grouting liquid with different grouting amounts to differentiate each local position upward. Uplift to correct the uneven settlement of the subsidence soil layer.

As a preferred solution, in the step of fixing the steel pipe pile, the grouting steel pipe and the foundation into one body by pouring concrete foundation beams, specifically:

Several criss-crossing fixed steel bars are implanted on the ground of the foundation, and the foundation beams are formed by pouring concrete, and the steel pipe piles, the grouting steel pipes and the foundation are fixed as a whole.

As a preferred solution, in the step of using the foundation as a reaction force platform, it also includes:

If the ground of the foundation to be constructed is not a horizontal plane, a reaction force platform in a horizontal direction is constructed on the ground of the foundation.

Compared with the prior art, the method for ground reinforcement and rectification provided by the present invention has the following beneficial effects:

In the present invention, the steel pipe pile is pressed into the first pile hole by means of the anchor rod static pressure construction method, and the grouting liquid is passed through the steel pipe pile to compact and reinforce the deep soil body, and after the grouting is completed, use The pressurizing component locks the steel pipe pile, and then directional reinforcement is performed on the shallow soil body through the grouting steel pipe in the second pile hole, and the pressure value change of the steel pipe pile is monitored during grouting. If the pressure value of the steel pipe piles is lost, the pressure components are used to compensate and pressurize the steel pipe piles to ensure the bearing capacity of a single steel pipe pile. , respectively, from the deep and shallow parts, compacting and strengthening the subsidence soil layer under the foundation, repeated multiple grouting and simultaneous grouting at multiple points to realize the slow and directional uplift of the settled soil layer, and carry out the uneven settlement between the foundations. Reinforcement and rectification can effectively reduce or eliminate the uneven settlement that has occurred and the inclination of the overall building. At the same time, the steel pipe pile, grouting steel pipe and the original foundation are connected by the newly poured foundation beam to strengthen the rigidity of the foundation and realize the Reinforcement and rectification are combined into one.

Description of drawings

FIG. 1 is a schematic diagram of a pile-pressing state applying a method for ground reinforcement and deviation correction according to a preferred embodiment of the present invention.

FIG. 2 is a schematic diagram showing the assembly of a steel pipe pile, a first grouting pipe and a second grouting pipe in the method for correcting deviation of foundation reinforcement according to the preferred embodiment of the present invention.

FIG. 3 is a schematic diagram of a reaction force platform in a method for ground reinforcement and deviation correction applying a preferred embodiment of the present invention.

FIG. 4 is a schematic diagram of the plane layout of the grouting steel pipe applying the method for rectifying deviation of the foundation reinforcement according to the preferred embodiment of the present invention.

FIG. 5 is a schematic cross-sectional view of a grouting steel pipe applying the method for correcting deviation of foundation reinforcement according to a preferred embodiment of the present invention.

FIG. 6 is a schematic diagram of a construction completion state of applying the method for ground reinforcement and deviation correction according to the preferred embodiment of the present invention.

In the figure: 1. The first pile hole; 2. The anchor bar; 3. The steel pipe pile; 4. The grouting outlet; 5. The grouting steel pipe; 6. The diamond-shaped pile tip; The second grouting pipe; 9. The grouting plug; 10. The reaction platform; 11. The first pile pressing block; 12. The second pile pressing block; 13. The jack;

Detailed ways

The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and embodiments. The following examples are intended to illustrate the present invention, but not to limit the scope of the present invention.

In the description of the present invention, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", The orientation or positional relationship indicated by "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying the indicated device or Elements must have a particular orientation, be constructed and operate in a particular orientation and are therefore not to be construed as limitations of the invention.

In the description of the present invention, it should be understood that the terms "connected", "connected", "fixed" and other terms used in the present invention should be understood in a broad sense, for example, it may be a fixed connection or a detachable connection, or It can be a mechanical connection or a welded connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two elements or the interaction relationship between the two elements, unless otherwise expressly defined . For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

As shown in FIG. 1 to FIG. 6 , a preferred embodiment of the present invention provides a foundation reinforcement and deviation correction method, which includes the following steps: opening a first pile hole 1 on the ground of the foundation to be constructed and extending to the deep soil body, and in the first pile hole 1 An anchor rod reinforcement bar 2 is implanted around a pile hole 1; the foundation is used as a reaction force platform 10, and the steel pipe pile 3 is pressed into the first pile hole 1 by means of anchor rod static pressure construction; The grout is squeezed and grouted through the grouting outlet 4 of the steel pipe pile 3, and the deep soil body is compacted and reinforced by the repeated grouting method of "grouting-cleaning-grouting"; after the grouting is completed , fix the pressurized component by the anchor bar 2, and use the pressurized component to temporarily lock the steel pipe pile 3; open a plurality of second pile holes on the ground of the foundation to be constructed or the ground between two foundations And extend to the shallow soil body, insert grouting steel pipe 5 in each of the second pile holes, the grouting liquid is squeezed and grouted through the grouting steel pipe 5, and the grouting method is repeated to the shallow layer in the same way. Local directional reinforcement is performed on the soil body, so that the subsidence soil layer below the foundation is lifted upward and rectified; during the grouting process of the grouting steel pipe 5, the pressure change value of the steel pipe pile 3 is obtained, and the steel pipe pile 3 is judged. Whether the pressure change value of the pipe pile 3 exceeds the preset value, if so, use the pressurizing component to compensate and pressurize the steel pipe pile 3 to ensure the bearing capacity of the steel pipe pile 3; The pressurizing assembly is removed, concrete is poured into the steel pipe pile 3 , and the steel pipe pile 3 , the grouting steel pipe 5 and the foundation are fixed as a whole by pouring concrete foundation beams 15 .

Based on the above-mentioned technical feature of the foundation reinforcement and deviation correction method, the steel pipe pile 3 is pressed into the first pile hole 1 by means of the anchor rod static pressure construction method, and the grouting liquid is passed through the steel pipe pile 3 to compress the deep soil. After the grouting is completed, the steel pipe pile 3 is locked with a pressurizing component, and the shallow soil body is directionally reinforced through the grouting steel pipe 5 in the second pile hole. The change of the pressure value of the steel pipe pile 3 is monitored. If the pressure value of the steel pipe pile 3 is lost, the pressure value of the steel pipe pile 3 is compensated and pressurized by the pressurizing component to ensure a single steel pipe pile. The bearing capacity of 3, through the directional reinforcement process of hole bottom mixing and quick-setting compaction, respectively, from the deep and shallow parts, compaction and reinforcement of the subsidence soil layer under the foundation, repeated grouting and multi-point simultaneous grouting to achieve the settlement of soil layer Slowly directional lifting, strengthening and rectifying the uneven settlement that has occurred between the foundations, can effectively reduce or eliminate the uneven settlement that has occurred and the inclination of the overall building. 3. The grouting steel pipe 5 is connected with the original foundation to strengthen the rigidity of the foundation and realize the integration of reinforcement and correction.

Before construction, the steel pipe pile 3 needs to be calculated and prefabricated. As shown in Figure 2, firstly, according to the upper load of the building and the distance between the piles, the characteristic value of the bearing capacity of the single pile is calculated and determined, and then according to the site geology The length of the steel pipe pile 3 is estimated according to the conditions. The static pressure steel pipe pile 3 used can usually pass through the clay layer and the fully weathered layer. The strong weathered layer can enter 1-2m, and the moderately weathered rock layer cannot enter. According to the estimated pile length and the characteristic value of the single pile bearing capacity, the steel pipe pile 3 with a diameter of 127, 159 or 250 mm and a wall thickness of 8-14 mm is selected. If the calculated pile diameter is too large, the distance between the steel pipe piles 3 can be appropriately compressed to reduce the characteristic value of the bearing capacity of the single pile, thereby reducing the pile diameter and avoiding the difficulty of pile pressing.

According to the estimated pile length and pile diameter, first make the steel pipe pile 3. The length of each steel pipe is not less than 2.0m, which can be determined according to the actual situation on site. The diameter of the bar is 14-16mm, the length of 200mm of steel bars or three pieces of 200×40×10mm (length×width×thickness) steel sheets are tied and welded, and the slurry outlet 4 is arranged within the range of 1-2m above the pile bottom to realize the injection The slurry rapidly solidifies in the deep position of the subsidence soil layer, and plays an uplifting and directional effect on the subsidence soil layer. The bottom of the steel pipe pile 3 is provided with a diamond-shaped pile tip 6, which is convenient for pile pressing construction.

In this embodiment, the step of extruding and grouting the configured grouting liquid through the grouting outlet 4 of the steel pipe pile 3 further includes: completing the pile before pressing the A first grouting pipe 7 (diameter 45-50mm, wall thickness 3-4mm) is welded in the pile 3, and a second grouting pipe 8 is inserted into the first grouting pipe 7 and extends to the grouting outlet 4, The grouting liquid is directly squeezed and reinforced to the bottom of the steel pipe pile 3 through the second grouting pipe 8 .

Among them, a slurry stopper 9 is provided between the outer wall of the first grouting pipe 7 and the inner wall of the steel pipe pile 3, and a steel plate is welded in the pipe at a distance of 2m from the pile bottom as the slurry stopper 9 for isolation. In dense grouting, the grouting plug 9 prevents the grouting liquid from flowing upward, and the grouting plug 9 is welded by steel plates.

In this embodiment, a first pile hole 1 is opened on the ground of the foundation to be constructed and extended to the deep soil body, and the steps of implanting the anchor reinforcement bar 2 around the first pile hole 1 are as follows: to be constructed The first pile hole 1 is drilled on the foundation ground, the diameter of the first pile hole 1 is slightly larger than the diameter of the steel pipe pile 3, and the surrounding of the first pile hole 1 is planted. For the pile cap beam steel bar and the threaded anchor bar steel bar 2, if the foundation ground is not a horizontal plane, such as an inclined plane or a concave-convex surface, a horizontally set construction platform should be constructed first as the reaction force platform 10.

In this embodiment, in the step of pressing the steel pipe pile 3 into the first pile hole 1 by means of anchor bolt static pressure construction, it also includes: the pile pressing pressure on the steel pipe pile 3 and the vertical In order to maintain the vertical pressure of the steel pipe pile 3, and make the pile pressure acting on the steel pipe pile 3 not exceed the maximum pile pressure. The pile pressing process must be continuous and keep the pile section vertical. The pile pressing force cannot exceed the design maximum pile pressing force, and the pressure, the verticality of the pile, the intermittent time of connecting the pile, the connection quality of the pile and the pressing depth, and the final pile should be checked in time. It is controlled according to the principle of combining the pile pressing load and the steady-state sinking amount.

In this embodiment, as shown in FIG. 1 , in the step of fixing the pressurized component through the anchor rod 2 and using the pressurized component to temporarily lock the steel pipe pile 3 , the specific steps are: The first pile pressing block 11 of the compression assembly is fixed on the ground of the foundation through the anchor rod reinforcement 2 , and the second pile driving block 12 of the compression assembly is fixed to the ground through the anchor rod reinforcement rod 2 . Above the first pile driving block 11, a jack 13 is arranged between the first pile driving block 11 and the second pile driving block 12, and the jack 13 is used to apply prestress to the steel pipe pile 3 . When the pressure loss is too large, the jack 13 can be used to re-press the steel pipe pile 3 to ensure the single pile bearing capacity of the steel pipe pile 3 .

Wherein, the anchor bar 2 is a threaded steel bar anchor, and the anchor bar 2 is provided with a nut for adjusting the position of the first pile pressing block 11 and the second pile pressing block 12, through the nut The first pile pressing block 11 is fixed, and then the second pile pressing block 12 is fixed by the anchor rod steel bar 2 and the nut, so as to realize the progressive bolt sealing pile structure, which is convenient and simple to operate and temporarily locked. The steel pipe pile 3 can adjust the pressure value of the steel pipe pile 3 to ensure that the steel pipe pile 3 has proper pre-stressing during the pile sealing process, realize the cooperative work of the pile-soil foundation, and effectively eliminate the later settlement.

Further, the number of the anchor bars 2 is multiple, and the anchor bars 2 are arranged around the steel pipe piles 3 in a rectangular array, so that the pressure acting on the steel pipe piles 3 is more uniform.

Among them, by repeatedly grouting the steel pipe pile 3 for many times, after each grouting, rinse the residual grout in the pipe with clean water, and then perform grouting, so as to form the repeated grouting of "grouting-cleaning-grouting" The slurry method can achieve the effect of slow lifting.

In this embodiment, the grouting liquid is configured by cement slurry, water glass and liquid water, the water-cement ratio of the cement slurry is 1:0.5-1.0, and the The volume ratio of liquid water is (1.0-1.5): 1: (2-3) in order, which realizes the process of quick-setting, compacting, directional reinforcement, and slowly lifts and corrects deviation.

长短结合，局部挤密加固基础底下土体，实现多局部位置同时注浆，实现对桩底以上地层进行挤密注浆，多重管注浆加固钢管桩3周边范围内，主要受力土层定向抬升，进一步减少差异沉降。In this embodiment, as shown in FIG. 4 and FIG. 5 , the opening direction of the second pile holes is vertical or oblique, and each of the second pile holes faces the steel pipe pile 3 . Grid-like capillary grouting steel pipes 5 with a length of 5m to 8m are arranged in the subsidence soil layer.

Combination of length and length, local compaction and reinforcement of the soil under the foundation, to achieve simultaneous grouting in multiple local locations, to achieve compaction and grouting of the stratum above the pile bottom, and multi-pipe grouting to reinforce the surrounding area of the steel pipe pile 3, the main stress soil layer Directional uplift to further reduce differential settlement.

In this embodiment, the grouting liquid is squeezed and grouted through the grouting steel pipe 5, and local directional reinforcement is performed on the shallow soil body in the same repeated grouting method, so that the settled soil below the foundation In the steps of layer uplifting and deviation correction, the specific steps are: dividing the configured grouting liquid into multiple groups, and passing the grouting liquid of each group through the grouting steel pipe 5 to repeat “grouting-cleaning-grouting” Squeeze grouting to carry out multiple directional reinforcement for multiple local positions of the settled soil layer, so that the settled soil layer gradually rises upward and tends to a stable state, wherein, different grouting steel pipes 5 adopt different grouting amount The grouting liquid is used to strengthen each local position in a differentiated way, and then through the progressive recompression of the steel pipe piles 3, the reinforcement, lifting and deviation correction are synchronously achieved, so as to achieve the purpose of correcting the uneven settlement of the settled soil layer. .

The grouting steel pipe 5 is a single-bolt type steel pipe, and the overall order of grouting can be from the outside to the inside. The grouting steel pipe 5 can be grouted for multiple groups of the grouting liquid, through the method of "repeating a small amount of times many times", until the uneven settlement of the foundation soil layer tends to be stable, or after it is raised to the design requirements and stabilized , the grouting can be stopped. Different grouting steel pipes 5 are used to use the grouting liquid with different grouting amounts to lift up each local position in a differentiated manner, that is, the lifting amplitude of different positions is different, so as to overcome the uneven settlement of the settled soil layer. In order to achieve the purpose of rectification, real-time monitoring of buildings and foundation pits should be strengthened during grouting to avoid disturbing buildings and supporting equipment, and to adjust grouting pressure and grouting volume in a timely manner to realize information-based construction.

The grouting steel pipe 5 can be repeatedly grouted for many times. After each grouting, rinse the residual grout in the pipe with clean water, keep the grouting steel pipe 5 clean, and seal it with a cover. When grouting next time, insert a small diameter into the pipe. The inner grouting pipe can start the double-liquid grouting repeatedly to avoid multiple hole formation, that is, the repeated grouting method of "grouting-cleaning-grouting". The grouting pressure of the grouting steel pipe 55 is 0.8-2.0 MPa, and the depth of the grouting port of the grouting steel pipe 55 is 5-8m, which can be appropriately deepened according to the conditions of the base soil layer. The grouting material also adopts double-liquid slurry. , the solidification time of the grouting liquid is not more than 10s, and the grouting speed is not more than 70 liters/min, and the proportion is finally determined by the field test.

In this embodiment, in the step of fixing the steel pipe pile 3, the grouting steel pipe 5 and the foundation as a whole by pouring concrete foundation beams 15, the concrete step is: implanting the steel pipe on the ground of the foundation. The fixed steel bars 14 are crisscrossed and cast into a foundation beam 15 through concrete, and the steel pipe pile 3, the grouting steel pipe 5 and the foundation are fixed as a whole. The type and quantity of the fixed steel bars 14 need to meet the shear resistance check calculation of the section, and the outer wall of the steel pipe pile 3 and the original foundation soil layer should be filled with ultra-fine cement slurry to ensure that the steel pipe pile 3 and the original The effective connection of the foundation soil layer is fixed.

The application example of the actual situation is used as a supplementary explanation. The foundation pit support project of the medical complex building of Nanfang Hospital (Phase I) is located in the Nanfang Hospital of Nanfang Medical University, Guangzhou Avenue, Guangzhou City. 35.00m, the perimeter of the foundation pit is about 400m, and the excavation depth of the foundation pit is about 12.30-15.40m. Within the excavation depth of the foundation pit, the backfill, alluvial clay layer, sand layer, plastic and hard residual cohesive soil layer, etc. are sequentially exposed. The bottom of the foundation pit is mainly located in the clay layer, and partially in the fully weathered rock layer. The surrounding environment of the foundation pit is complex. The north side is adjacent to the surgical building (13 floors, independent foundation, a basement floor, the foundation depth is about 5.2m), and it is about 6.0m away from the sideline of the basement of the medical complex building; the east side is the dormitory building with floors 2-19. It is about 18.3m from the basement side. The basement side on the south side of the foundation pit is 5.0m away from the road. The independent foundation of the 5-storey medical technology building on the northwest side of the foundation pit is about 8.3m away from the sideline of the basement. There are water supply and drainage pipelines and power supply lines under the east and south roads. Precision instruments such as DSG and r-knife are installed in the basement of the surgical building on the north side, and precision instruments such as a nuclear magnetic resonance (MRI) imager are installed in the medical technology building on the northwest side, which are sensitive to disturbances such as deformation, vibration and noise and need to be protected.

During the construction of the foundation pit supporting structure and the plain concrete piles of the main structure, uneven settlement occurred on the north and west sides of the foundation pit. The maximum settlement of the southeast corner of the surgical building reached 38.5mm, and the inclination rate of the southeast corner reached 4.25‰. Exceeded design control value. In order to avoid the danger of continuous development of settlement, the construction of the support structure was suspended at the construction site, and the foundation reinforcement rectification structure and reinforcement rectification method in this embodiment were used to carry out the construction of the single (strip) foundation on the north and west sides of the foundation pit and the soil under the foundation. Rescue reinforcement, realize directional uplifting and reinforcement correction for areas with large settlement, and reduce the uneven settlement of the foundation soil layer. After the reinforcement and rectification, the uneven settlement of the surgical building was effectively controlled. After the southeast corner (the maximum settlement point) was properly lifted, the settlement was stabilized at about 15mm, and the inclination rate of the corner point was restored to about 1.5‰, which ensured that the main structure of the surgical building continued to be maintained. Safe use, with good social and economic benefits.

To sum up, the embodiment of the present invention provides a foundation reinforcement and deviation correction method with the following advantages: (1) Prestress is applied to the top of the steel pipe pile 3 by means of anchor bolt static pressure, so as to effectively pull the foundation soil layer, and reduce repetition during construction. Uneven settlement and uplift realize the synergy between the foundation soil layer, the steel pipe pile 3 and the foundation, and form the traction type steel pipe pile 3, so as to give full play to the bearing capacity of the foundation subsoil, and try not to change the stress state of the original structure; ( 2) A first grouting pipe 77 is set on the steel pipe pile 3, and extrusion grouting is performed through the second grouting pipe 8. The triple pipe grouting reinforces the surrounding soil of the steel pipe pile 3, and locally lifts the pile soil from the deep part. Community, reducing the uneven settlement (differential settlement) that has occurred; (3) arranging the grouting steel pipe 5 in a grid shape, local directional extrusion grouting, long and short combination, compaction and reinforcement of the soil under the foundation, to achieve directional realization The main stressed soil layer in the shallow layer is directional uplifted to further reduce differential settlement; (4) Directional grouting lifts and corrects deviation, adopts the directional reinforcement technology of hole bottom mixing and quick-setting compaction, and compacts and reinforces the soil under the foundation from the deep and shallow parts respectively. (5) The construction is convenient, and the prestressed anchorage can be adjusted. The repeated progressive threaded pile sealing structure is adopted, and the load loss of the anchor static pressure pile is observed by the pressure gauge. If there is any loss, it can be recompressed, which can ensure the bearing capacity of the single pile and effectively reduce the settlement after the grouting is stopped; (6) The construction period is short, and the construction cost can be saved by about 20-50% compared with the conventional method, and the construction period can be saved by about 30-60%.

The above description is only the preferred embodiment of the present invention. It should be pointed out that for those skilled in the art, without departing from the technical principle of the present invention, several improvements and replacements can be made. These improvements and replacements It should also be regarded as the protection scope of the present invention.

Claims (10)

1. A foundation reinforcement deviation rectifying method is characterized by comprising the following steps:

the method comprises the following steps of (1) forming a first pile hole in the ground of a foundation to be constructed and extending to a deep soil body, and implanting anchor rod reinforcing steel bars around the first pile hole;

pressing the steel pipe pile into the first pile hole by using the foundation as a counter-force platform in an anchor rod static pressure construction mode;

extruding and grouting the prepared grouting liquid through a grout outlet of the steel pipe pile, and compacting and reinforcing the deep soil body in a repeated grouting mode of grouting, cleaning and grouting;

after grouting is finished, fixing a pressurizing assembly through the anchor rod reinforcing steel bars, and temporarily locking the steel pipe pile by using the pressurizing assembly;

a plurality of second pile holes are formed in the ground of a foundation to be constructed or the ground between two foundations and extend to a shallow soil body, grouting steel pipes are inserted into the second pile holes, grouting liquid is extruded and grouted through the grouting steel pipes, local directional reinforcement is carried out on the shallow soil body in the same repeated grouting mode, and a settled soil layer below the foundation is lifted upwards and corrected;

in the process of grouting the steel pipe, acquiring a pressure change value of the steel pipe pile, judging whether the pressure change value of the steel pipe pile exceeds a preset value, if so, performing compensation pressurization on the steel pipe pile by using the pressurization assembly to ensure the bearing capacity of the steel pipe pile;

and after the reinforcement and the correction are finished, the pressurizing assembly is disassembled, concrete is poured into the steel pipe pile, and the steel pipe pile, the grouting steel pipe and the foundation are fixed into a whole through pouring a concrete foundation beam.

2. The method for correcting the foundation stabilization according to claim 1, wherein the step of performing extrusion grouting on the prepared grouting liquid through a grout outlet of the steel pipe pile further comprises:

and welding a first grouting pipe in the steel pipe pile, inserting a second grouting pipe into the first grouting pipe and extending to the grout outlet, and extruding and grouting the grouting liquid through the second grouting pipe.

3. The method for correcting the foundation stabilization according to claim 1, wherein in the step of pressing the steel pipe pile into the first pile hole by the anchor rod static pressure construction, the method further comprises:

and detecting the pile pressing pressure and the verticality of the steel pipe pile so as to keep the vertical pressurization of the steel pipe pile and ensure that the pile pressing pressure acting on the steel pipe pile does not exceed the maximum pile pressing pressure.

4. The method for correcting the foundation stabilization according to claim 1, wherein in the step of fixing a pressurizing assembly through the anchor rod reinforcing steel bars and temporarily locking the steel pipe pile by using the pressurizing assembly, the method specifically comprises the following steps:

fixing a first pile pressing block of the pressurizing assembly on the ground of the foundation through the anchor rod steel bars, fixing a second pile pressing block of the pressurizing assembly above the first pile pressing block through the anchor rod steel bars, arranging a jack between the first pile pressing block and the second pile pressing block, and applying prestress to the steel pipe pile by using the jack.

5. The deviation rectifying method for foundation stabilization according to claim 4, wherein the anchor bar is provided with nuts for adjusting the positions of the first pile block and the second pile block.

6. The foundation stabilization deviation rectifying method according to claim 1, wherein the grouting liquid is prepared from cement paste, water glass and liquid water, and the volume ratio of the cement paste to the water glass to the liquid water is 1.0-1.5: 1: 2 to 3.

7. The method for correcting the foundation stabilization according to claim 1, wherein the opening direction of each second pile hole is vertical or oblique, and the tail end of each second pile hole faces the steel pipe pile.

8. The method for correcting the foundation stabilization according to claim 1, wherein in the step of performing extrusion grouting on the grouting liquid through the grouting steel pipe and performing local directional reinforcement on the shallow soil body in the same repeated grouting manner to lift and correct the deviation of the settlement soil layer below the foundation, the method specifically comprises the following steps:

dividing the prepared grouting liquid into a plurality of groups, repeatedly extruding and grouting each group of grouting liquid through the grouting steel pipe, and directionally reinforcing a plurality of local positions of a subsided soil layer for a plurality of times so as to gradually lift the subsided soil layer upwards and tend to a stable state, wherein different grouting steel pipes adopt the grouting liquid with different grouting amounts so as to upwards lift each local position in a differentiation manner and correct uneven settlement of the subsided soil layer.

9. The method for correcting the foundation stabilization according to claim 1, wherein in the step of fixing the steel pipe piles, the grouting steel pipes and the foundation into a whole by pouring concrete foundation beams, the method comprises the following specific steps:

and implanting a plurality of criss-cross fixed steel bars into the ground of the foundation, pouring concrete into a foundation beam, and fixing the steel pipe pile, the grouting steel pipe and the foundation into a whole.

10. The method for correcting deviation of foundation stabilization according to any one of claims 1 to 9, wherein the step of using the foundation as a counterforce platform further comprises:

and if the ground of the foundation to be constructed is not the horizontal plane, constructing a horizontal reaction platform on the ground of the foundation.

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