CN117248571A - Pile foundation deviation compensation construction method for secondary grouting - Google Patents
Pile foundation deviation compensation construction method for secondary grouting Download PDFInfo
- Publication number
- CN117248571A CN117248571A CN202311342577.6A CN202311342577A CN117248571A CN 117248571 A CN117248571 A CN 117248571A CN 202311342577 A CN202311342577 A CN 202311342577A CN 117248571 A CN117248571 A CN 117248571A
- Authority
- CN
- China
- Prior art keywords
- grouting
- pile foundation
- grid
- geotechnical cloth
- deflection
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000010276 construction Methods 0.000 title claims abstract description 38
- 239000004744 fabric Substances 0.000 claims abstract description 57
- 238000012937 correction Methods 0.000 claims abstract description 35
- 239000002689 soil Substances 0.000 claims abstract description 21
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 20
- 239000010959 steel Substances 0.000 claims abstract description 20
- 239000013307 optical fiber Substances 0.000 claims abstract description 19
- 238000000034 method Methods 0.000 claims abstract description 16
- 238000012806 monitoring device Methods 0.000 claims abstract description 14
- 238000012544 monitoring process Methods 0.000 claims abstract description 13
- 230000002787 reinforcement Effects 0.000 claims abstract description 13
- 239000000463 material Substances 0.000 claims abstract description 5
- 238000009434 installation Methods 0.000 claims abstract description 4
- 239000002002 slurry Substances 0.000 claims description 16
- 238000009792 diffusion process Methods 0.000 claims description 4
- 239000004746 geotextile Substances 0.000 claims description 4
- 230000002159 abnormal effect Effects 0.000 claims description 3
- 238000002360 preparation method Methods 0.000 claims description 3
- 238000007569 slipcasting Methods 0.000 claims description 3
- 238000011065 in-situ storage Methods 0.000 claims 1
- 238000009958 sewing Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 239000004568 cement Substances 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 230000008439 repair process Effects 0.000 description 2
- 230000002776 aggregation Effects 0.000 description 1
- 238000004220 aggregation Methods 0.000 description 1
- 238000009412 basement excavation Methods 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 230000002427 irreversible effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 238000005067 remediation Methods 0.000 description 1
- 239000011435 rock Substances 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D33/00—Testing foundations or foundation structures
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D15/00—Handling building or like materials for hydraulic engineering or foundations
- E02D15/02—Handling of bulk concrete specially for foundation or hydraulic engineering purposes
- E02D15/04—Placing concrete in mould-pipes, pile tubes, bore-holes or narrow shafts
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D15/00—Handling building or like materials for hydraulic engineering or foundations
- E02D15/08—Sinking workpieces into water or soil inasmuch as not provided for elsewhere
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D17/00—Excavations; Bordering of excavations; Making embankments
- E02D17/02—Foundation pits
- E02D17/04—Bordering surfacing or stiffening the sides of foundation pits
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D29/00—Independent underground or underwater structures; Retaining walls
- E02D29/045—Underground structures, e.g. tunnels or galleries, built in the open air or by methods involving disturbance of the ground surface all along the location line; Methods of making them
- E02D29/05—Underground structures, e.g. tunnels or galleries, built in the open air or by methods involving disturbance of the ground surface all along the location line; Methods of making them at least part of the cross-section being constructed in an open excavation or from the ground surface, e.g. assembled in a trench
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D3/00—Improving or preserving soil or rock, e.g. preserving permafrost soil
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D35/00—Straightening, lifting, or lowering of foundation structures or of constructions erected on foundations
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D5/00—Bulkheads, piles, or other structural elements specially adapted to foundation engineering
- E02D5/02—Sheet piles or sheet pile bulkheads
- E02D5/03—Prefabricated parts, e.g. composite sheet piles
- E02D5/04—Prefabricated parts, e.g. composite sheet piles made of steel
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D5/00—Bulkheads, piles, or other structural elements specially adapted to foundation engineering
- E02D5/22—Piles
- E02D5/64—Repairing piles
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D2600/00—Miscellaneous
- E02D2600/10—Miscellaneous comprising sensor means
Landscapes
- Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Life Sciences & Earth Sciences (AREA)
- Paleontology (AREA)
- Civil Engineering (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Composite Materials (AREA)
- Agronomy & Crop Science (AREA)
- Soil Sciences (AREA)
- Piles And Underground Anchors (AREA)
Abstract
The invention discloses a pile foundation deflection compensation construction method for secondary grouting, which comprises the steps of firstly, preparing materials, binding a reinforcement cage and preparing a grid-type geotechnical cloth bag with a grouting pipe; then, performing foundation pit construction by adopting an open cut method, and arranging steel sheet pile supports; the steel sheet pile support is used as a template, a steel reinforcement cage is lowered, and pouring construction is carried out after optical fibers are embedded in the steel reinforcement cage; after the pile foundation is initially set, removing the steel sheet pile support, installing a plurality of grid-type geotechnical cloth bags around the pile foundation, and filling soil and backfilling after the installation; connecting the pre-buried optical fiber with an optical fiber strain monitor to form a pile foundation deflection monitoring device; the pile foundation inclination deviation is monitored through the pile foundation deviation monitoring device, when the optical fiber inclination deviation reaches a set threshold value, the corresponding grid-type geotechnical cloth bag is subjected to grouting through the grouting pipe, and the pile foundation is extruded through grouting pressure to carry out compensation correction. The invention has simple construction, short period, low cost, real-time monitoring and controllability. The high-precision correction can be performed without depending on experience of constructors.
Description
Technical Field
The invention belongs to the field of civil engineering, relates to the technical field of pile foundation inclination regulation and control, and in particular relates to a pile foundation deviation compensation construction method for secondary grouting.
Background
Due to the stress characteristics of the structure, the characteristics of concrete materials, the local rock characteristics, soil conditions and the like, the pile foundation can be offset in the use process. The same bridge foundation and building foundation can generate offset phenomenon when piling soil body in peripheral excavation foundation, and correction is also needed, which has great hidden trouble for engineering safety if not handled in time.
The main method for regulating and controlling the pile foundation deflection at present is as follows: the bridge foundation adopts a mode of adding tie bars to steel pipe concrete, and the lateral thrust born by the arch abutment is balanced by applying the tie bars during construction, so that the occurrence of deflection is restrained. However, the existing adjusting mode has the defect that manual control is excessively relied on, for example, after concrete in a certain steel pipe is poured, if the inclination displacement of the arch abutment is found to be out of limit, one-time tie rod force adjustment is carried out, but obviously, the adjusting mode is only a post-remediation adjusting mode, because the deviation of the arch abutment in the concrete pouring process can be out of limit, irreversible damage is generated on the arch abutment, meanwhile, the arch abutment is difficult to accurately simulate, the specific tie rod force adjustment value is difficult to accurately find, and the risk of overlarge or overlarge adjustment exists. The method is characterized in that the foundation of the building is excavated, the foundation is regulated and controlled by using a hydraulic jack, and then a supporting system is poured, and the method has the defects of complex construction and excessive uncontrollable factors, and cannot be adopted for some foundations limited by terrain conditions. The problem of foundation deviation caused by the use of a large number of buildings at present is increasingly remarkable, and how to scientifically and effectively reduce the occurrence rate of foundation deviation and improve the safety performance of the buildings is a problem to be solved urgently.
Disclosure of Invention
The invention aims at providing a pile foundation deflection compensation construction method for secondary grouting according to the current situation, wherein the pile foundation deflection compensation construction method is not excessively dependent on manual experience regulation and control, the inclination deflection of a pile foundation is monitored through a distributed optical fiber sensing technology, and proper grouting pressure and grouting amount are calculated to correct the pile foundation deflection. The method has the advantages of simple construction process, reliable quality, short construction period and controllable construction.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:
the invention discloses a pile foundation deflection compensation construction method for secondary grouting, which comprises the following steps:
preparing materials, binding reinforcement cages and preparing a grid-type geotechnical cloth bag with grouting pipes;
constructing a foundation pit, adopting an open cut method to construct the foundation pit, and arranging steel sheet pile supports;
the steel sheet pile support is used as a template, a steel reinforcement cage is lowered, and pouring construction is carried out after optical fibers are embedded in the steel reinforcement cage;
after the pile foundation is initially set, removing the steel sheet pile support, installing a plurality of grid-type geotechnical cloth bags around the pile foundation, and filling soil and backfilling after the installation;
connecting the pre-buried optical fiber with an optical fiber strain monitor to form a pile foundation deflection monitoring device;
the pile foundation inclination deviation is monitored through the pile foundation deviation monitoring device, when the optical fiber inclination deviation reaches a set threshold value, the corresponding grid-type geotechnical cloth bag is subjected to grouting through the grouting pipe, and the pile foundation is extruded through grouting pressure to carry out compensation correction.
According to the invention, the grid-type geotechnical cloth bag is embedded around the pile foundation creatively, the offset pile foundation is corrected by adjusting the grouting pressure and the grouting amount in a secondary grouting mode, the construction can be standardized, the manual experience is not needed, the construction mode is simple, the correction cost is low, and the construction progress of a main body is not influenced.
Further, the grid-type geotechnical cloth bag is formed by sewing double-layer geotechnical cloth, grid-type pouring units are formed by sewing on the geotechnical cloth at intervals, small holes for slurry to flow are reserved between adjacent grid-type unit cells, and through grid-type arrangement, the geotechnical cloth bag is prevented from being excessively expanded locally, so that the contact area between the geotechnical cloth bag and pile foundation is small during grouting, and the correction strength is insufficient; through the restriction of the grid unit, the inner slurry of the grid-type geotechnical cloth bag can be in full contact with the surface of the pile foundation during grouting, and the maximum correction force is provided under the same grouting pressure.
Further, the grid-type geotechnical cloth bags are arranged in a layered mode in the height direction of the pile foundation, each layer of at least two grid-type geotechnical cloth bags encircle the pile foundation, the layered mode in the height direction is beneficial to inclined righting, and each layer of geotechnical cloth bags encircle a plurality of layers, so that different directions can be corrected.
Further, the grid-type geotechnical cloth bag is at least divided into an upper layer, a middle layer and a lower layer, and by arranging grouting points (at least two grouting points on each height) in the upper layer, the middle layer and the lower layer, the upper layer, the lower layer and the lower layer are simultaneously corrected, so that the correction efficiency can be improved.
Further, when the inclination deviation of the pile foundation is monitored, the deviation is calculated every 1-2 months. The pile foundation can be monitored once a day as required, and when the continuous monitoring is carried out for 6 months, the pile foundation basically cannot deviate after the deviation meets the requirement.
Further, the grouting method for the corresponding grid-type geotechnical cloth bag through the grouting pipe comprises the following steps:
calculating grouting pressure and pre-estimated grouting amount according to pile soil parameters and pile foundation inclination angles;
preparing slurry and a grouting device according to the calculated grouting pressure and the estimated grouting amount;
grouting the grid-type geotechnical cloth bag needing grouting of the corrected pile foundation by using a grouting device, and grouting according to the calculated grouting pressure;
when the grouting amount reaches 70-85% of the pre-estimated amount, detecting the inclination and offset angle of the pile foundation again through a pile foundation offset monitoring device, and if the pile foundation correction amplitude is normal, continuing grouting until the estimated grouting amount is normal, and increasing the monitoring frequency until the pile foundation compensation correction is completed;
if the pile foundation correction amplitude is abnormal, checking the grouting device, and then continuing grouting until the estimated grouting amount is reached, and increasing the monitoring frequency until the pile foundation compensation correction is completed.
Further, the preparation slurry is prepared by adopting a mode of excavating a slurry pond on site.
Further, the grouting pressure calculation formula is as follows:
q＝ΔΓKZ
q is grouting pressure, Z is grouting point depth, K is pressure coefficient, the value is 0.03-0.028, and DeltaΓ is grouting pressure adjustment coefficient; the setting of the grouting pressure adjustment coefficient is determined according to the water-cement ratio index of the grouting liquid, and when the water cement ratio is large, the grouting liquid has good fluidity and high purity, and the grouting pressure adjustment coefficient can be properly reduced; when the fluidity is poor and the purity is low, the grouting pressure adjustment coefficient needs to be improved, and the value is generally 0.9-1.4; according to the invention, the optimal range of the grouting pressure adjusting coefficient is 0.8-1.2 under the condition of correcting the pile foundation. The invention introduces the pressure coefficient and the pressure adjustment coefficient, so that the grouting pressure calculated by the invention is more accurate, and the minimum pressure meeting the correction condition can be selected, thereby reducing the requirement on equipment.
Further, the grid geotechnical cloth bag is divided into an upper layer, a middle layer and a lower layer which are equidistantly arranged, three grouting points are arranged on the pile foundation, the middle layer and the lower layer, and the grouting pressure of each grouting point is calculated according to the following formula:
q 3 ＝ΔΓKZ 3 ＝HsinθΔΓK
wherein q 1 、q 2 、q 3 Grouting pressures of upper, middle and lower grouting points are respectively represented, Z 1 、Z 2 、Z 3 The depth of the upper, middle and lower grouting points is respectively represented, H represents pile foundation height, and theta represents pile foundation inclination angle.
Further, the estimated calculation formula of the grouting amount of each grouting point is as follows:
in the above, Q 1 、Q 2 、Q 3 The estimated grouting amounts of the upper, middle and lower grouting points are respectively shown;
a is a grouting coefficient, and the value is 0.7-0.9;
beta is the slip casting loss coefficient, and the value range is 1.1-1.4;
r is grouting diffusion radius;
N 1 、N 2 、N 3 respectively representing soil layer porosities at upper, middle and lower grouting points, N 2 ′、N 3 ' is the equivalent soil layer porosity of the middle layer and the lower layer grouting points respectively.
Compared with the prior art, the invention has the following beneficial effects:
1. according to the invention, the pile foundation deflection is accurately monitored by utilizing the pile foundation deflection monitoring device without relying on manual experience, after the inclination deflection is monitored, the pile foundation is verified and corrected by adopting an empirical formula technology grouting pressure and pre-estimated grouting quantity and finally combining grouting effect feedback, so that the pile foundation correction is standardized, even an inexperienced constructor can carry out according to the construction manual written by the invention, and the correction is independent of personal experience of constructors.
2. The invention uses geotechnical cloth bag unit for grouting correction in the prior art to prevent correction failure caused by local aggregation of grouting, and uniformly distributes grouting slurry on the surface of a pile foundation by using geotechnical cloth bag unit for correction, so that the maximum correction force under the same grouting pressure can be obtained.
3. The invention has simple construction, short period, low cost, real-time monitoring and controllability. For the characteristic of large traffic of bridges, the method can not influence normal traffic operation as much as possible, can monitor the variation of pile foundation deflection in real time, and accurately control grouting amount according to monitoring data, so that the problem of pile foundation deflection is solved.
Drawings
FIG. 1 is a flow chart of a pile foundation deviation compensation construction method of the secondary grouting.
Fig. 2 is a schematic flow chart of monitoring pile foundation inclination deviation by the pile foundation deviation monitoring device in an embodiment of the invention.
Fig. 3 is a schematic view of a single grid-type geotextile bag after deployment.
Fig. 4 is a schematic front view of the grid-type geotechnical cloth bag after being installed on a pile foundation.
Fig. 5 is a schematic diagram of the rear side of the grid-type geotechnical cloth bag installed on pile foundation.
FIG. 6 is a schematic cross-sectional view of a grid-type geotechnical cloth bag after being installed on pile foundation.
Fig. 7 is a schematic view of a connector for installing a grid-type geotechnical cloth bag.
FIG. 8 is a schematic diagram of the modified pile foundation of the present invention.
Fig. 9 is an equivalent schematic diagram of a single format unit after expansion.
100-grid geotechnical cloth bags, 110-grouting openings, 120-connecting pieces, 121-first connecting pieces, 122-second connecting pieces, 123 connecting grooves and 124-connecting heads; 200-pile foundation, 300-grouting pipe and 400-grouting point.
Detailed Description
Embodiments of the present invention are described in further detail below with reference to the accompanying drawings and examples. The following examples are illustrative of the invention but are not intended to limit the scope of the invention.
In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, merely to facilitate description of the present invention and simplify the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "connected," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.
As shown in fig. 1 and 2, the invention provides a construction method for compensating deflection of a pile foundation 200 of secondary grouting, which comprises the following steps:
s1, preparing materials, binding reinforcement cages and preparing a grid-type geotechnical cloth bag 100 with a grouting pipe 300;
in the embodiment, the reinforcement cage binding is performed by adopting the construction standard in the prior art; the grid-type geotechnical cloth bags 100 are formed by sewing double-layer geotechnical cloth, grid-type pouring units are formed by sewing on the geotechnical cloth at intervals, small holes for slurry to flow are reserved between adjacent cells, a grouting port 110 is reserved in the middle of each grid-type geotechnical cloth bag 100, and the unfolded grid-type geotechnical cloth bags 100 are shown in fig. 3. By dividing the geotechnical cloth belt into unit formats, slurry can be uniformly dispersed during grouting, but not concentrated in a local part, so that grouting correction cannot be smoothly completed.
S2, foundation pit construction is carried out, field leveling is carried out firstly, then foundation pit construction is carried out by adopting an open cut method according to a design drawing, and steel sheet pile support is arranged;
s3, using the steel sheet pile support as a template, lowering a reinforcement cage, embedding optical fibers in the reinforcement cage, and then performing pouring construction, and using the optical fibers to monitor whether the later-stage pile foundation 200 is inclined;
s4, after the pile foundation 200 is initially set, dismantling a steel sheet pile support, installing a plurality of grid-type geotechnical cloth bags around the pile foundation 200, and filling soil and backfilling after the installation;
in this embodiment, the two geotechnical bags of each layer are directly connected by a connecting piece to form a pile foundation 200 wrapped around the inside, as shown in fig. 4 to 6; the connecting pieces can be in the form of binding ropes or special connecting pieces, for example, as shown in the figure, the connecting pieces comprise two first connecting pieces 121 and one second connecting piece 122, and the two first connecting pieces 121 are respectively sewn on the side parts of two grid-type geotechnical cloth bags to be spliced; the opposite sides of the two first connecting pieces 121 are respectively provided with a connecting groove 123, and two ends of the second connecting piece 122 are respectively detachably fixed in the connecting grooves 123 on two sides through a clamping structure.
As shown in fig. 7, the first connecting member 121 may be made of plastic with a certain elasticity, the cross-sectional area of the connecting slot 123 is larger than that of the opening, the two ends of the second connecting member 122 are provided with connecting heads 124 with enlarged cross-sections, the connecting heads 124 are plugged into the connecting slot 123 by external force to connect the first connecting member 121 and the second connecting member 122 (after the external force is extruded, the two sides of the connecting slot 123 are deformed and opened), and the structure can be quickly connected and can meet the requirements; the invention can ensure that the shape of the grid-type geotechnical cloth bag is kept before backfilling, and the shape of the grid-type geotechnical cloth bag is kept by the backfilling after backfilling, so that the connecting function of a connecting piece is not needed, and the strength of the connecting mode is enough to meet the requirement.
Each grid-type geotechnical cloth bag is reserved with a grouting opening 110, a grouting pipe 300 is arranged on the grouting opening 110 and extends to the position above the top of the pile foundation 200, and preparation is made for subsequent grouting; in general, the grouting openings 110 should be disposed in the middle of the whole grid-type geotechnical cloth bag, and the grouting pipe 300 may be a sleeve valve pipe with a diameter of 30 mm.
S5, connecting the pre-buried optical fiber with an optical fiber strain monitor to form a pile foundation 200 deviation monitoring device, wherein the optical fiber detection technology is adopted by the prior art, and the invention does not improve the part, for example, CN113899343B, CN106643542, CN217358508U, an inclination sensor and the like can be adopted;
s6, monitoring inclination deviation of the pile foundation 200 through a pile foundation 200 deviation monitoring device, wherein the monitoring frequency is 1-7 days each time; when the inclination deviation of the optical fiber reaches a set threshold value, grouting is carried out on the corresponding grid-type geotechnical cloth bag through the grouting pipe 300, and compensation correction is carried out by extruding the pile foundation 200 through grouting pressure.
The grouting method for the corresponding grid-type geotechnical cloth bag through the grouting pipe 300 is as follows:
s6.1, calculating grouting pressure and pre-estimated grouting quantity according to pile soil parameters and the inclination angle of the pile foundation 200;
s6.1.1, calculating grouting pressure
The grouting pressure is q, and the burying depth of the grouting pipe 300 is z 1 To select z 1 Calculated here, the lateral static soil pressure born by the pile foundation 200 wrapped by the grid-type geotechnical cloth bag 100 is sigma 1 ＝k 0 γz 1 As long as the grouting pressure q is less than or equal to sigma 1 The soil body can not generate lateral deformation displacement. Grouting pressure q of selected injection>σ 1 Due to grouting pressureStatic soil pressure greater than the lateral direction can generate lateral soil deformation during grouting. Wherein k is 0 The soil pressure coefficient is shown, and gamma is the weight of the 200-degree soil of the buried pile foundation.
After the grouting pressure coefficient and the grouting pressure adjustment coefficient are introduced, the grouting pressure calculation formula is as follows:
q＝ΔΓKZ
q is grouting pressure, Z is grouting point 400 depth, K is pressure coefficient, the value is 0.03-0.028, deltaΓ is grouting pressure adjustment coefficient, and the value is generally 0.9-1.4.
As shown in the figure, the pile foundation 200 has a height H, an offset angle θ, and a horizontal offset x of the pile foundation 200
For correction of the inclined pile foundation 200, the best mode is to divide upper, middle and lower three layers of grouting correction, so that the grid-type geotechnical cloth bags are divided into upper, middle and lower three layers of grouting points 400 at equal intervals, as shown in fig. 8, in the inclined state, the upper grouting point 400 is supposed to be arranged on the right side of the pile foundation 200, the middle grouting point 400 is arranged on the right side, the lower grouting point 400 is arranged on the left side of the pile foundation 200, and the correction can be completed by slightly rotating the pile foundation 200 up and down respectively as shown by arrows in fig. 8 during grouting (the actual inclined angle is far smaller than the angle drawn in the drawing); the calculation formula of the grouting pressure of each grouting point 400 is as follows:
q 3 ＝ΔΓKZ 3 ＝HsinθΔΓK
wherein q 1 、q 2 、q 3 Grouting pressures, Z, of the upper, middle and lower grouting points 400 are respectively shown 1 、Z 2 、Z 3 The depth of the upper, middle and lower grouting points 400 is shown, H represents the height of the pile foundation 200, and θ represents the inclination angle of the pile foundation 200.
S6.1.2, the estimated calculation formula of the grouting amount of each grouting point 400 is as follows:
in the above, Q 1 、Q 2 、Q 3 The estimated grouting amounts of the upper, middle and lower grouting points 400 are respectively represented;
a is a grouting coefficient, and the value is 0.7-0.9;
beta is the slip casting loss coefficient, and the value range is 1.1-1.4;
r is grouting diffusion radius and is mainly related to the volume of each grid unit of the grid geotechnical cloth bag after expansion; in this embodiment, half of the minimum values of the length, width and height of each grid unit is taken as the grouting diffusion radius, and the calculation formula is as follows:
ζ, η are the length, width, and height of the expanded grille unit.
N 1 、N 2 、N 3 The soil layer porosities at the upper, middle and lower grouting points 400 are respectively represented and obtained through geological exploration; n (N) 2 ′、N 3 ' equivalent soil layer porosities of the middle and lower grouting points 400 respectively, wherein
S6.2, preparing slurry and a grouting device according to the calculated grouting pressure and the estimated grouting amount;
preparing slurry, namely excavating a slurry pool on site, and preparing the slurry on site; the grouting device can adopt a HFV5D, KBY50/70 type dual-liquid grouting pump and is provided with a high-pressure grouting pipe 300 pipeline system and a grouting device.
S6.3, grouting the grid-type geotechnical cloth bag which needs grouting for the corrected pile foundation 200 by using a grouting device, and grouting according to the calculated grouting pressure;
s6.4, when the grouting amount reaches 70-85% of the pre-estimated amount, detecting the inclination and offset angle of the pile foundation 200 again through the pile foundation 200 offset monitoring device, and if the correction amplitude of the pile foundation 200 is normal, continuing grouting to the estimated grouting amount if the correction amplitude of the pile foundation 200 is normal, and increasing the monitoring frequency until the compensation correction of the pile foundation 200 is completed;
if the correction amplitude of the pile foundation 200 is abnormal, checking the grouting device, and then continuing grouting until the estimated grouting amount is reached and increasing the monitoring frequency until the compensation correction of the pile foundation 200 is completed.
The method for judging whether the corrected amplitude is normal is to see whether the difference between the corrected amplitude and the calculated value after grouting is within an allowable range, for example, the error is less than 20%.
In step S6.4, it is determined whether the grouting amount is within the allowable range from the calculated value when the grouting amount reaches 70% and 85% of the estimated amount, respectively, so as to check the grouting device in time and prevent failure in correction due to insufficient grouting pressure caused by failure of the grouting device.
It should be noted that if the pile foundation 200 deviation monitoring device monitors that the inclination deviation of the pile foundation 200 is within the range satisfying the requirement for 6 months continuously, grouting repair is not required.
After grouting repair, the grouting is continuously monitored for 3 months, and when the pile foundation 200 deviates again, the grouting is continuously corrected through the residual other grid-type geotechnical cloth bags.
The above embodiments are only for illustrating the present invention, and are not limiting of the present invention. While the invention has been described in detail with reference to the embodiments, those skilled in the art will appreciate that various combinations, modifications, and substitutions can be made thereto without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (10)
1. The pile foundation deviation compensation construction method for secondary grouting is characterized by comprising the following steps of:
preparing materials, binding reinforcement cages and preparing a grid-type geotechnical cloth bag with grouting pipes;
constructing a foundation pit, adopting an open cut method to construct the foundation pit, and arranging steel sheet pile supports;
the steel sheet pile support is used as a template, a steel reinforcement cage is lowered, and pouring construction is carried out after optical fibers are embedded in the steel reinforcement cage;
after the pile foundation is initially set, removing the steel sheet pile support, installing a plurality of grid-type geotechnical cloth bags around the pile foundation, and filling soil and backfilling after the installation;
connecting the pre-buried optical fiber with an optical fiber strain monitor to form a pile foundation deflection monitoring device;
the pile foundation inclination deviation is monitored through the pile foundation deviation monitoring device, when the optical fiber inclination deviation reaches a set threshold value, the corresponding grid-type geotechnical cloth bag is subjected to grouting through the grouting pipe, and the pile foundation is extruded through grouting pressure to carry out compensation correction.
2. The construction method for compensating pile foundation deflection of secondary grouting according to claim 1, wherein the grid-type geotextile bag is sewn by double-layer geotextile, grid-type pouring units are sewn on the geotextile at intervals, and small holes for slurry to flow are reserved between adjacent unit grids.
3. The construction method for compensating pile foundation deflection of secondary grouting according to claim 1, wherein the grid-type geotechnical cloth bags are layered in the pile foundation height direction, and each layer of at least two grid-type geotechnical cloth bags encircle the pile foundation.
4. The construction method for compensating pile foundation deflection of secondary grouting according to claim 3, wherein the grid-type geotechnical cloth bag is at least divided into an upper layer, a middle layer and a lower layer.
5. The construction method for compensating pile foundation deflection of secondary grouting according to claim 1, wherein the deflection is calculated every 1-2 months when the pile foundation deflection is monitored.
6. The construction method for compensating pile foundation deflection of secondary grouting according to claim 3, wherein the grouting method for the corresponding grid-type geotechnical cloth bag through the grouting pipe is as follows:
calculating grouting pressure and pre-estimated grouting amount according to pile soil parameters and pile foundation inclination angles;
preparing slurry and a grouting device according to the calculated grouting pressure and the estimated grouting amount;
grouting the grid-type geotechnical cloth bag needing grouting of the corrected pile foundation by using a grouting device, and grouting according to the calculated grouting pressure;
when the grouting amount reaches 70-85% of the pre-estimated amount, detecting the inclination and offset angle of the pile foundation again through a pile foundation offset monitoring device, and if the pile foundation correction amplitude is normal, continuing grouting until the estimated grouting amount is normal, and increasing the monitoring frequency until the pile foundation compensation correction is completed;
if the pile foundation correction amplitude is abnormal, checking the grouting device, and then continuing grouting until the estimated grouting amount is reached, and increasing the monitoring frequency until the pile foundation compensation correction is completed.
7. The construction method for compensating pile foundation deflection of secondary grouting according to claim 6, wherein the preparation of slurry is performed by excavating a slurry pond in situ.
8. The construction method for compensating pile foundation deflection of secondary grouting according to claim 6, wherein the grouting pressure is calculated as follows:
q＝ΔΓKZ
q is grouting pressure, Z is grouting point depth, K is pressure coefficient, the value is 0.03-0.028, deltaΓ is grouting pressure adjusting coefficient, and the value is generally 0.9-1.4.
9. The construction method for compensating pile foundation deflection of secondary grouting according to claim 8, wherein the upper, middle and lower layers of the grid-type geotechnical cloth bag are equidistantly arranged, three grouting points are arranged on the pile foundation, the middle and lower layers of the grid-type geotechnical cloth bag, and the grouting pressure of each grouting point is calculated according to the following formula:
q 3 ＝ΔΓKZ 3 ＝HsinθΔΓK
wherein q 1 、q 2 、q 3 Grouting pressures of upper, middle and lower grouting points are respectively represented, Z 1 、Z 2 、Z 3 The depth of the upper, middle and lower grouting points is respectively represented, H represents pile foundation height, and theta represents pile foundation inclination angle.
10. The construction method for compensating pile foundation deflection of secondary grouting according to claim 9, wherein the estimated calculation formula of the grouting amount of each grouting point is as follows:
in the above, Q 1 、Q 2 、Q 3 The estimated grouting amounts of the upper, middle and lower grouting points are respectively shown;
a is a grouting coefficient, and the value is 0.7-0.9;
beta is the slip casting loss coefficient, and the value range is 1.1-1.4;
r is grouting diffusion radius;
N 1 、N 2 、N 3 respectively representing soil layer porosities at upper, middle and lower grouting points, N 2 ′、N 3 ' is the equivalent soil layer porosity of the middle layer and the lower layer grouting points respectively.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311342577.6A CN117248571A (en) | 2023-10-13 | 2023-10-13 | Pile foundation deviation compensation construction method for secondary grouting |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311342577.6A CN117248571A (en) | 2023-10-13 | 2023-10-13 | Pile foundation deviation compensation construction method for secondary grouting |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117248571A true CN117248571A (en) | 2023-12-19 |
Family
ID=89132946
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311342577.6A Pending CN117248571A (en) | 2023-10-13 | 2023-10-13 | Pile foundation deviation compensation construction method for secondary grouting |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117248571A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117702727A (en) * | 2024-02-06 | 2024-03-15 | 江苏筑港建设集团有限公司 | Cast-in-place pile construction technology |
-
2023
- 2023-10-13 CN CN202311342577.6A patent/CN117248571A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117702727A (en) * | 2024-02-06 | 2024-03-15 | 江苏筑港建设集团有限公司 | Cast-in-place pile construction technology |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN117248571A (en) | Pile foundation deviation compensation construction method for secondary grouting | |
| CN111779045B (en) | Foundation reinforcement deviation rectifying method | |
| CN107268636A (en) | The diaphragm wall foundation ditch that the steel cylinder or steel sheet pile of a kind of seal groove and occlusion structure are constituted is with going along with sb. to guard him and construction method | |
| CN113638398A (en) | Active dynamic control method for stress of bag type grouting soil body | |
| CN112900264A (en) | Suspension bridge major diameter secant pile gravity type anchorage foundation enclosure structure and construction method | |
| CN101806073A (en) | Resistance-free load test device and method for upper extension section of foundation pile | |
| JP2019044566A (en) | Foundation post grouting method of submerged caisson | |
| CN110206071A (en) | A kind of diaphram wall seam reinforcement means and device | |
| CN206784327U (en) | A kind of stone masonry dam poor quality dam grouting reinforcing structure | |
| CN108978680A (en) | A kind of muck soil elevator foundation pit supporting construction device and method | |
| CN211523271U (en) | Automatic control system for mud-water balance open caisson vehicle station in soft soil area | |
| CN110241863B (en) | Soft soil foundation pit excavation process pipe gallery deformation control device and control method thereof | |
| CN107940102B (en) | Underground raw water pipeline protection construction method | |
| CN114319323A (en) | Construction method of upright post pile | |
| CN214273664U (en) | Pre-supporting structure of underground railway station close-fitting and underneath-passing existing station | |
| CN216108526U (en) | Underground continuous wall structure for foundation pit support | |
| CN214194466U (en) | Reserved grouting hole structure for foundation treatment of embedded large-scale vibration equipment | |
| CN209636839U (en) | Concrete gravity dam drain in dam foundation pore structure | |
| CN106948315A (en) | A kind of stone masonry dam dam grouting reinforcing structure inferior and method | |
| CN113266019A (en) | Construction method of foundation pit steel pipe support system | |
| CN111648788A (en) | Tunnel protection construction method adjacent to subway line | |
| CN201635099U (en) | Unresisted load test device for pile top lengthening segment of cast-in place pile | |
| CN217298895U (en) | Sand bed geological pile foundation hole bottom grouting device | |
| CN104110030A (en) | Steel casing lead hole type pile planting construction technology | |
| CN113293767B (en) | Underground structure upper soil body construction system and method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |