CN216739569U - Grouting isolation wall for protecting high-speed rail bridge pile foundation - Google Patents
Grouting isolation wall for protecting high-speed rail bridge pile foundation Download PDFInfo
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- CN216739569U CN216739569U CN202122876238.9U CN202122876238U CN216739569U CN 216739569 U CN216739569 U CN 216739569U CN 202122876238 U CN202122876238 U CN 202122876238U CN 216739569 U CN216739569 U CN 216739569U
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Abstract
The utility model relates to a grouting isolation wall for protecting a high-speed rail bridge pile foundation, which is positioned in a soil body and comprises a ground beam, a composite soil layer and a plurality of grouting steel perforated pipes; the plurality of grouting steel perforated pipes are arranged in at least two rows on the horizontal plane, and each grouting steel perforated pipe is vertically arranged; the ground beam is positioned above the grouting steel perforated pipes and wraps the upper ends of the grouting steel perforated pipes, so that the upper ends of all the grouting steel perforated pipes are connected by one ground beam; the composite soil layer surrounds each grouting steel floral tube, and all the composite soil layers are connected with each other to form an isolation wall structure. The utility model constructs the ground beam, wraps the upper end of the grouting steel perforated pipe, connects the grouting steel perforated pipe into a whole to bear force jointly, and the ground beam and the grouting steel perforated pipe act together, although the isolation pile is not adopted, the effect is equivalent to the arrangement of the isolation pile. The utility model belongs to the field of building construction.
Description
Technical Field
The utility model relates to the field of building construction, in particular to a grouting isolation wall for protecting a high-speed rail bridge pile foundation.
Background
High-speed railway often accompanies the intersection or adjacent of multiple mode of transportation through the city, and near high-speed railway bridge foundation can lead to the soil body around the basis to remove because of neighbouring engineering construction, and removal soil (its soil pressure) can lead to the bridge pile foundation to produce the displacement on acting on the pile foundation of building thing. The high-speed rail is fast, the requirement on the smoothness of the track is high, and construction near the high-speed rail can greatly affect the running safety of the high-speed rail. High-speed railway functioning speed is very fast, receives the effect of side direction soil pressure to produce the displacement when the pile foundation, and then leads to the pier to produce the displacement, finally makes high-speed railway bridge orbit produce and warp, and such deformation surpasss 2mm will exert an influence to driving safety and driving travelling comfort. Therefore, in order to ensure the safety of tunnel construction and the normal operation of a high-speed rail, the construction of the isolation pile is firstly carried out before the construction near the high-speed rail foundation, the soil body near the pile foundation of the high-speed rail bridge is grouted and reinforced, and the movement of the soil body around the pile foundation of the high-speed rail bridge is limited, so that the deformation of the pile foundation is reduced, and the safety of implemented objects is ensured.
The existing isolation wall mainly comprises a cast-in-situ bored pile and a post-grouting isolation wall, needs large-scale mechanical construction, and inevitably disturbs a soil body in the drilling process, so that the cost is high, and the construction period is long. The isolation wall with the structure has the advantages that isolation piles arranged in rows in construction are arranged, the isolation piles form an isolation wall structure, the construction process is complex due to the fact that a plurality of isolation piles are constructed, effective connection is not needed among the isolation piles, all the isolation piles can not bear force together, soil bodies can not be consolidated to form the continuous isolation wall, and the effect of the isolation wall is affected.
SUMMERY OF THE UTILITY MODEL
Aiming at the technical problems in the prior art, the utility model aims to: the grouting isolation wall for protecting the high-speed rail bridge pile foundation has a good isolation effect without adopting an isolation pile.
In order to achieve the purpose, the utility model adopts the following technical scheme:
a grouting isolation wall for protecting a high-speed rail bridge pile foundation is positioned in soil and comprises a ground beam, a composite soil layer and a plurality of grouting steel perforated pipes; the plurality of grouting steel perforated pipes are arranged in at least two rows on the horizontal plane, and each grouting steel perforated pipe is vertically arranged; the ground beam is positioned above the grouting steel perforated pipes and wraps the upper ends of the grouting steel perforated pipes, so that the upper ends of all the grouting steel perforated pipes are connected by one ground beam; the composite soil layer surrounds each grouting steel floral tube, and all the composite soil layers are connected with each other to form an isolation wall structure.
Preferably, the slip-casting steel flower tube comprises a tube body, a sharp conical head and a plurality of angle steel barbs; the head is located the lower extreme of body, is equipped with a plurality of eyelets on the body, and every eyelet outside is provided with an angle steel barb of welding at the body outer wall.
Preferably, the eyelets are arranged spirally at 90 degrees on the tube body, two eyelets are arranged on the same cross section of the tube body, and the two eyelets are positioned on the same diameter.
Preferably, in the barb of the angle steel, the right-angle edge of the angle steel inclines from the inner lower part to the outer upper part; a gap is arranged between the lower end of the barb of the angle steel and the pipe body.
Preferably, the length of the pipe body is 8m, the outer diameter is 114mm, and the wall thickness is 5 mm; the length of the head is 20 cm; the inner diameter of each eyelet is 8mm, and the axial distance between adjacent eyelets in the axial direction is 30 cm; the specification of the angle steel is L30 multiplied by 3, and the included angle between the axis of the angle steel and the axis of the pipe body is 30 degrees; the length of the grouting steel perforated pipe in the ground beam is 300mm, and no eyelet is arranged in the range of 50cm at the upper end of the pipe body.
Preferably, the number of the grouting steel perforated pipes is two lines; in the overlooking direction, two rows of grouting steel perforated pipes are arranged in a staggered manner and are arranged in a quincunx shape.
Preferably, the distance between the one-line grouting steel perforated pipe on the inner side and the outer side line of the high-speed rail bridge pile foundation is 700 mm; the row spacing between two rows of grouting steel perforated pipes is 433 mm; in the same row, the distance between adjacent grouting steel perforated pipes is 500 mm.
Preferably, the ground beam is in a cube shape, and the upper end face of the ground beam is flush with the upper end face of the soil body.
Preferably, the width of the ground beam is the distance between the inner side and the outer side; the width of the ground beam is 833mm, the height of the ground beam is 500mm, and the distance between the inner side of the ground beam and the outer side line of the high-speed railway bridge pile foundation is 500 mm; the ground beam is prepared by concrete pouring.
Preferably, the composite soil body layer is a cement-water glass-undisturbed soil composite soil body layer.
The principle of the utility model is as follows:
the construction method comprises the steps of firstly carrying out grouting isolation wall construction before construction near a high-speed rail bridge pile foundation, grouting and reinforcing soil bodies near the high-speed rail bridge pile foundation, solidifying the soil bodies near the high-speed rail bridge pile foundation into a cement-water glass-original soil composite soil layer, constructing a ground beam to wrap the upper end of a grouting steel perforated pipe so that the grouting steel perforated pipe bears force together, forming the composite soil layer in the grouting solidification process, mutually fusing the composite soil layers into a whole to form an isolation wall structure, stabilizing the stratum, limiting movement of the soil bodies around the high-speed rail bridge pile foundation in adjacent engineering construction, reducing deformation of the foundation and ensuring stability and safety of the high-speed rail bridge pile foundation.
In summary, the present invention has the following advantages:
1. the construction ground beam wraps the upper end of the grouting steel perforated pipe, the grouting steel perforated pipe is connected into a whole to bear force jointly, the ground beam and the grouting steel perforated pipe act jointly, although isolation piles are not adopted, the effect of the construction ground beam is equivalent to that of the isolation piles.
2. The slip casting steel floral tube adopts the barb structure, can improve the anchor power of slip casting steel floral tube and soil body, and the barb outside the eyelet enables the thick liquid to flow from barb top and below simultaneously, makes thick liquid and soil body fully fuse simultaneously.
3. The composite soil layer is a cement-water glass-undisturbed soil composite soil layer, namely formed by cement-water glass double-liquid grouting. The cement-water glass double-liquid grouting can reinforce a soft stratum and limit the displacement of a soil body, has high condensation speed, and can be quickly solidified particularly in karst geology or a water-rich soil layer, so that the reinforcing effect is achieved. The cement-water glass double-liquid grouting can also play a good water stopping role in a crack development zone.
4. The grouting steel perforated pipes are arranged in a staggered manner and are arranged in a quincunx manner, so that a hole-separating perfusion method is convenient to adopt. And a hole isolation filling method is adopted, so that the middle hole cannot be leaked outwards during deep grouting. The filling of the separation holes can avoid adverse effects on the filling quality of adjacent grouting steel perforated pipes when the grouting steel perforated pipes are constructed.
5. The construction method has the advantages of simple structure, simple and controllable construction process, low cost and short construction period, effectively isolates the soil pressure generated during construction near the high-speed rail bridge pile foundation, ensures the stability and safety of the high-speed rail bridge pile foundation and reduces the influence during large-scale construction near the high-speed rail bridge pile foundation by adopting a mode that a down-the-hole drill is used for guiding holes, constructing the grouting steel perforated pipe, combining cement-water glass double-liquid grouting with an original soil body to form an isolation wall and constructing a ground beam to ensure the integral stress of the grouting steel perforated pipe.
Drawings
Fig. 1 is a perspective view of a slip-casting steel floral tube.
Fig. 2 is a schematic view of a top view of a slip-casting steel floral tube.
Fig. 3 is a partially enlarged view of the grouting steel floral tube.
Fig. 4 is a plan view of the arrangement of grouting insulation walls and high-speed rail bridge pile foundations.
Fig. 5 is an elevation view of the arrangement of grouting insulation walls and high-speed rail bridge pile foundations.
In the figure, 1 is the head, 2 is the angle steel barb, 3 is the body, 4 are the eye, 5 are high-speed railway bridge pile foundations, 6 are the grade beam, 7 are the hole, 8 are slip casting steel floral tube.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and detailed description.
A grouting isolation wall for protecting a high-speed rail bridge pile foundation is positioned in soil and comprises a ground beam, a composite soil layer and a plurality of grouting steel perforated pipes; the plurality of grouting steel perforated pipes are arranged in at least two rows on the horizontal plane, and the number of the grouting steel perforated pipes is two in the embodiment; each grouting steel perforated pipe is vertically arranged; the ground beam is positioned above the grouting steel perforated pipes and wraps the upper ends of the grouting steel perforated pipes, so that the upper ends of all the grouting steel perforated pipes are connected by one ground beam; the composite soil layer surrounds each grouting steel floral tube, and all the composite soil layers are mutually fused and connected to form an isolation wall structure.
A grouting insulation wall for protecting a high-speed rail bridge pile foundation is prepared by the following steps: a. digging a groove on the outer side of a high-speed rail bridge pile foundation, and drilling a hole in the groove by using a down-the-hole drill; b. inserting a grouting steel perforated pipe with an angle steel barb into a hole, and adopting cement-water glass double-liquid grouting to form a cement-water glass-original soil composite soil layer, wherein the composite soil layers are mutually connected to form an isolation wall, and original soil is original soil and soil at the location of a high-speed railway bridge pile foundation; c. and pouring concrete in the grooves, constructing a ground beam, and connecting the grouting steel perforated pipes into a whole. The method comprises the following specific steps:
(1) step a:
during large-scale construction near a high-speed rail bridge pile foundation, in order to reduce disturbance of the construction process to the high-speed rail bridge pile foundation, a groove is firstly dug between the high-speed rail bridge pile foundation and a part to be constructed, in the embodiment, the width 833mm and the depth 500mm of the groove are provided, the inner side of the groove is 500mm away from the outer side line of the high-speed rail bridge pile foundation, a down-the-hole drill is adopted to drill two rows of holes in the groove along the high-speed rail bridge pile foundation, in the embodiment, the diameter of a drill bit of the down-the-hole drill is 160mm, a row of hole positions (taking the axis of the hole as a reference) on the inner side during drilling is 700mm away from the outer side line of the high-speed rail bridge pile foundation, the row distance of two rows of holes is 433mm, the distance between two adjacent holes on the same row of holes is 500mm, the distance between one hole and the nearest hole on the adjacent row of holes is 500mm, the two rows of holes are arranged in a staggered mode, and are arranged in a quincunx shape as shown in fig. 4. The position of the hole corresponds to the position of the grouting steel perforated pipe.
(2) Step b:
and inserting the grouting steel perforated pipe into the hole, wherein the exposed length of the grouting steel perforated pipe is 30 cm. The pipe body of the grouting steel perforated pipe is made of a national standard seamless steel pipe with the length of 8m, the outer diameter of 114mm and the wall thickness of 5 mm. The head of the front end of the grouting steel perforated pipe is processed into a pointed cone, and the length of the pointed cone is 20 cm. Holes are drilled on the pipe wall of the pipe body in a staggered mode every 30cm, and the diameter of each hole is 8 mm. The eyelets are arranged in a 90-degree spiral mode, only 2 eyelets are arranged on the same cross section, and the distance between grouting eyelets along the axial line is 30 cm. Set up the angle steel barb outside the eyelet, the angle steel specification is L30 x 3, and the axis of angle steel is 30 with the axis contained angle of body, and the marginal weld of angle steel is equipped with the clearance between the lower extreme of angle steel barb and the body at the outer wall of body, angle steel's edge weld. No hole is drilled within 50cm of the upper end of the pipe body.
The grouting adopts cement-water glass double-liquid grouting, the volume ratio of cement to water glass is 1:0.5, the grouting water cement ratio is 0.55:1, the cement adopts 42.5R ordinary portland cement, the concentration of the water glass is 35-42 Be, the modulus is 2.3-3.0, and the grouting pressure is 0.5 MPa-1.0 MPa. The grouting pressure needs to be determined by a site test to obtain a specific numerical value, so that the cement-water glass double-liquid slurry can be ensured to fully permeate into a soil body to form a cement-water glass-undisturbed soil composite soil body layer. Grouting pressure is obtained by looking at a pressure gauge of grouting equipment. And (3) pouring cement-water glass slurry from the bottom of the hole upwards, taking the drilled slag out of the hole by utilizing the buoyancy of the cement-water glass slurry, and stopping grouting when the slurry flowing out of the hole is the cement-water glass slurry. The grouting sequence is from outside to inside, and the jumping-hole construction is adopted at the same time, and the grouting is carried out in the single hole from bottom to top.
The concrete order of grouting is as follows:
firstly, grouting a row of grouting steel perforated pipes on the outer side; in the pressure injection, the same row of grouting steel perforated pipes are filled in separated holes, namely, the middle holes are filled after one grouting is performed, so that a curtain is formed, and the middle holes cannot seep outwards when grouting is performed deeply. If the grouting pressure is not improved all the time and the phenomenon of slurry overflow does not occur, the situation that cracks under the grouting steel floral tube develop or soil is loose and even a karst cave possibly exists is shown, at the moment, the middle part of the grouting steel floral tube is constructed as before, piles are added on the outer side for grouting, and the two ends are appropriately encrypted. During grouting, a small amount of grouting is performed on two sides for multiple times once, holes are swept for multiple times until the final hole is formed, a small amount of grouting is performed at the beginning, if underground water is found to be developed, grouting is difficult to complete, the amount of doped water glass is added according to a test, and after grouting is stable, continuous grouting is performed until two rows of holes are completely completed, namely, the principle of few holes at first and many holes at last is followed. During the fore-and-mid-term grouting, thick grout is adopted, and after the grouting pressure rises, thinner grout is gradually used for grouting. When the grouting pressure reaches the final pressure and exceeds 20 minutes, the grouting can be finished when the grout is still not blown out from the orifice. After grouting, plugging the pipe orifice: preventing the slurry from flowing back to the outside of the pipe.
(3) Step c:
and pouring concrete in the grooves, constructing a ground beam, and connecting the grouting steel perforated pipes into a whole. The thickness of the ground beam is 500mm, the width thereof is 833mm, the ground beam wraps the exposed 30cm of the tail end of the grouting steel perforated pipe, the reinforced concrete ground beam template is originally designed to adopt a shaping combined steel template, and C30 cast-in-situ commercial concrete. And (3) pouring the concrete in layers, wherein the thickness of each layer is 30-40 cm, and vibrating for 10-30 s by using an inserted vibrator in a quincunx shape until the surface of the concrete has laitance, does not sink and does not have bubbles. Pouring of concrete needs to be completed at one time, watering maintenance is carried out after pouring is completed, and the maintenance time is not less than 14 d. After initial setting, covering maintenance was started, and after final setting, watering (after 12 hours) and covering maintenance were performed.
The utility model has convenient construction and obvious horizontal force isolation effect. Need when high-speed railway bridge stake is close position construction, adopt the mode of constructing the isolated wall of slip casting near high-speed railway bridge stake, can effectively completely cut off the horizontal power to its production when constructing near high-speed railway bridge stake great scale, when near high-speed railway bridge stake excavation construction, also can reduce the vibration to the soil layer among the excavation process to reduce the risk that the excavation in-process soil body collapses.
Besides the modes mentioned in the above embodiments, the sizes of the grooves and the grouting steel floral tubes can be adjusted according to actual conditions, and the number of the grouting steel floral tubes can also be adjusted according to actual conditions. These variations are all within the scope of the present invention.
The above embodiments are only examples of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents and are included in the scope of the present invention.
Claims (10)
1. The utility model provides a protection high-speed railway bridge pile foundation's isolated wall of slip casting, is located the soil body, its characterized in that: comprises a ground beam, a composite soil layer and a plurality of grouting steel floral tubes; the plurality of grouting steel perforated pipes are arranged in at least two rows on the horizontal plane, and each grouting steel perforated pipe is vertically arranged; the ground beam is positioned above the grouting steel perforated pipes and wraps the upper ends of the grouting steel perforated pipes, so that the upper ends of all the grouting steel perforated pipes are connected by one ground beam; the composite soil layer surrounds each grouting steel floral tube, and all the composite soil layers are connected with each other to form an isolation wall structure.
2. The grouting insulation wall for protecting the high-speed rail bridge pile foundation according to claim 1, characterized in that: the grouting steel pattern pipe comprises a pipe body, a pointed conical head and a plurality of angle steel barbs; the head is located the lower extreme of body, is equipped with a plurality of eyelets on the body, and every eyelet outside is provided with an angle steel barb of welding at the body outer wall.
3. The grouting insulation wall for protecting the high-speed rail bridge pile foundation according to claim 2, characterized in that: the eyelets are spirally arranged on the pipe body at 90 degrees, two eyelets are arranged on the same cross section of the pipe body, and the two eyelets are located on the same diameter.
4. The grouting insulation wall for protecting the high-speed rail bridge pile foundation according to claim 2, characterized in that: in the barb of the angle steel, the right-angle edge of the angle steel inclines from the inner lower part to the outer upper part; a gap is arranged between the lower end of the barb of the angle steel and the pipe body.
5. The grouting insulation wall for protecting the high-speed rail bridge pile foundation according to claim 2, characterized in that: the length of the pipe body is 8m, the outer diameter is 114mm, and the wall thickness is 5 mm; the length of the head is 20 cm; the inner diameter of each eyelet is 8mm, and the axial distance between adjacent eyelets in the axial direction is 30 cm; the specification of the angle steel is L30 multiplied by 3, and the included angle between the axis of the angle steel and the axis of the pipe body is 30 degrees; the length of the grouting steel perforated pipe in the ground beam is 300mm, and no eyelet is arranged in the range of 50cm at the upper end of the pipe body.
6. The grouting insulation wall for protecting the high-speed rail bridge pile foundation according to claim 1, characterized in that: the number of the grouting steel perforated pipes is two lines; in the overlooking direction, two rows of grouting steel perforated pipes are arranged in a staggered manner and are arranged in a quincunx shape.
7. The grouting insulation wall for protecting the high-speed rail bridge pile foundation according to claim 6, characterized in that: the distance between the one-line grouting steel perforated pipe on the inner side and the outer side line of the high-speed rail bridge pile foundation is 700 mm; the row spacing between two rows of grouting steel perforated pipes is 433 mm; in the same row, the distance between adjacent grouting steel perforated pipes is 500 mm.
8. The grouting insulation wall for protecting the high-speed rail bridge pile foundation according to claim 1, characterized in that: the ground beam is cubic, and the up end is flushed with the up end of the soil body.
9. The grouting insulation wall for protecting a high-speed rail bridge pile foundation according to claim 8, characterized in that: the width of the ground beam is the distance between the inner side and the outer side; the width of the ground beam is 833mm, the height of the ground beam is 500mm, and the distance between the inner side of the ground beam and the outer side line of the high-speed railway bridge pile foundation is 500 mm; the ground beam is prepared by concrete pouring.
10. The grouting insulation wall for protecting the high-speed rail bridge pile foundation according to claim 1, characterized in that: the composite soil layer is a cement-water glass-undisturbed soil composite soil layer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122876238.9U CN216739569U (en) | 2021-11-23 | 2021-11-23 | Grouting isolation wall for protecting high-speed rail bridge pile foundation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122876238.9U CN216739569U (en) | 2021-11-23 | 2021-11-23 | Grouting isolation wall for protecting high-speed rail bridge pile foundation |
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| Publication Number | Publication Date |
|---|---|
| CN216739569U true CN216739569U (en) | 2022-06-14 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202122876238.9U Active CN216739569U (en) | 2021-11-23 | 2021-11-23 | Grouting isolation wall for protecting high-speed rail bridge pile foundation |
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| CN (1) | CN216739569U (en) |
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2021
- 2021-11-23 CN CN202122876238.9U patent/CN216739569U/en active Active
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