Construction method for pouring highway bridge and culvert abutment back roadbed based on flow-state sandy soil

Abstract

The embodiment of the invention discloses a construction method for pouring a highway bridge and culvert abutment back roadbed based on flow-state sandy soil, relates to the technical field of road and bridge transition section treatment, and aims to solve the problem of vehicle bump at a bridge head caused by the problem of differential settlement of a bridge abutment and a roadbed. The construction method for pouring the highway bridge and culvert abutment-back roadbed based on the flow-state sandy soil comprises the steps that the flow-state sandy soil is selected as abutment-back roadbed filler, and the filler is tiled and backfilled into an abutment-back roadbed foundation pit in a layered mode; paving a layer of pebbles on the bottommost filler layer to form a pebble layer; a pouring guide pipe net is laid on the stone layer, and the pouring guide pipe net is formed by a plurality of first guide pipes and second guide pipes; grouting equipment injects prefabricated mixed grout into a filler layer in the abutment back roadbed through a first guide pipe and a second guide pipe; and the prefabricated mixed slurry flows into the filler layer from the slurry dispersing holes, and the processes of filling and pouring the slurry are repeated until the top surface of the roadbed is filled with the slurry, so that the bridge and culvert abutment back roadbed is formed. The method is suitable for construction scenes of road and bridge transition sections.

Description

Technical Field

[0001] The invention relates to the technical field of road-bridge transition section treatment, and in particular to a construction method for pouring a highway bridge and culvert abutment back roadbed based on fluid sandy soil. Background Art

[0002] The abutment of a bridge or culvert is a supporting structure that connects the abutment or culvert to the main roadbed. It bears loads from the bridge deck, deadweight, traffic, etc. In actual applications, there is a large gap in stiffness between the soil and concrete connected on both sides of the abutment. Even if lime is used for reinforcement, the foundation at the bridge head will still produce differential settlement and transverse cracks, leading to the problem of vehicle jumping at the bridge head, which seriously affects driving safety and the service life of the project. Summary of the invention

[0003] In view of this, an embodiment of the present invention provides a construction method for pouring a highway bridge and culvert abutment back roadbed based on fluid sandy soil, which can reduce the risk of vehicle jumping at the bridge head caused by filler settlement.

[0004] To achieve the above object, the embodiments of the present invention adopt the following technical solutions: The embodiment of the present invention provides a construction method for pouring a highway bridge and culvert abutment roadbed based on fluidized sandy soil, comprising: liquefying the sandy soil to obtain filler for the bridge and culvert abutment; filling a road-bridge transition zone with the filler, leveling and compacting the filled filler to obtain a filler layer; laying a pouring conduit on the filler layer; injecting prefabricated slurry into the filler layer through the pouring conduit to obtain an abutment layer; repeatedly constructing the abutment layer in the road-bridge transition zone until it is filled to the top surface of the roadbed to obtain the bridge and culvert abutment.

[0005] According to a specific implementation manner of the embodiment of the present invention, the sandy soil is sandy soil obtained by excavating the road-bridge transition zone.

[0006] According to a specific implementation of the embodiment of the present invention, the thickness of the filler layer is 100 cm.

[0007] According to a specific implementation method of an embodiment of the present invention, laying a casting conduit on the packing layer includes: laying a full-length conduit in parallel on the packing layer, controlling the spacing between adjacent full-length conduits to be a first preset spacing; in an edge area of ​​the packing layer, coaxially laying short conduits equidistantly between the full-length conduits; the edge area is an area within 1 m from the edge of the packing layer; injecting prefabricated slurry into the packing layer through the casting conduit to obtain a backing layer, includes: injecting prefabricated slurry into the middle area of ​​the packing layer through the full-length conduit; injecting prefabricated slurry into the edge area of ​​the packing layer through the short conduit; and obtaining the backing layer after standing for a preset time.

[0008] According to a specific implementation of an embodiment of the present invention, before injecting prefabricated slurry into the filler layer through the casting conduit, the method further includes: axially piercing slurry holes based on a second preset spacing on a portion of the through-length conduit located in a middle area of ​​the filler layer; and axially piercing slurry holes based on the second preset spacing on a portion of the short conduit located in an edge area of ​​the filler layer.

[0009] According to a specific implementation of an embodiment of the present invention, before injecting the prefabricated slurry into the filler layer through the pouring conduit, the method further includes: marking a water level line on a mixing tank; adding the following components in parts by weight into the mixing tank: water, 0.8; cement, 1; high flow agent 0.04; after adding each component into the mixing tank, before filling, continuously stirring to obtain the prefabricated slurry.

[0010] According to a specific implementation of an embodiment of the present invention, the trial compressive strength standard of the prefabricated slurry is: Rs≥1.05Rb; wherein Rs is the trial compressive strength of the prefabricated slurry, and Rb is the designed compressive strength of the prefabricated slurry.

[0011] According to a specific implementation of the embodiment of the present invention, the fluidity of the prefabricated slurry is 210 mm to 230 mm.

[0012] According to a specific implementation method of an embodiment of the present invention, the injecting of prefabricated slurry into the filler layer through the pouring conduit includes: controlling the pouring pressure to 0.5~0.8Mpa, and injecting the prefabricated slurry into the filler layer through the pouring conduit; when the pouring pressure is 1.2~1.5Mpa, performing a pressure stabilization operation, and completing the injection of the prefabricated slurry after 0.8~1.2 minutes of pressure stabilization.

[0013] According to a specific implementation of the embodiment of the present invention, the horizontal deviation and the vertical deviation of the casting conduit are both no greater than 10 cm.

[0014] The construction method for pouring a highway bridge and culvert abutment roadbed based on fluidized sandy soil provided in an embodiment of the present invention fills the road-bridge transition zone layer by layer. After filling a layer of filler, prefabricated slurry is injected into the filler through a pouring conduit to obtain a dense abutment layer of expansive consolidated sandy soil. In this way, by repeatedly constructing the abutment layer until it is filled to the top surface of the roadbed, the bridge and culvert abutment obtained can reduce the risk of vehicle jumping at the bridge head caused by filler settlement. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 It is a schematic structural diagram of a first conduit (through-length conduit) of an implementation method of a construction method for pouring a highway bridge and culvert abutment back roadbed based on fluid sandy soil of the present invention; Figure 2 It is a schematic structural diagram of a second conduit (short conduit) of an implementation method of a construction method for pouring a highway bridge and culvert abutment back roadbed based on fluid sandy soil of the present invention; Figure 3 A side view of a bridge and culvert abutment back roadbed according to an embodiment of a construction method for pouring a highway bridge and culvert abutment back roadbed based on fluid sandy soil according to the present invention; Figure 4 It is a cross-sectional view of a bridge and culvert abutment back roadbed in a construction method for pouring a highway bridge and culvert abutment back roadbed based on fluid sandy soil in one embodiment of the present invention. DETAILED DESCRIPTION

[0017] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0018] It should be clear that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] The embodiment of the present invention provides a construction method for pouring a highway bridge and culvert abutment back roadbed based on fluid sandy soil, which can reduce the risk of vehicle jumping at the bridge head caused by filler settlement.

[0020] The following combination Figure 1 , Figure 2 , Figure 3 , Figure 4 , the implementation modes of the present invention are further described.

[0021] The embodiment of the present invention provides a construction method for pouring a highway bridge and culvert abutment back roadbed based on fluid sandy soil, comprising: Select fluid sandy soil as the back-platform roadbed filler, and after cleaning the surface of the roadbed foundation pit, use the filler to backfill the back-platform roadbed foundation pit in layers; wherein, after the bottom layer is filled, the filler is leveled and compacted; a layer of gravel is leveled on the bottom filler layer and leveled to form a gravel layer; a casting conduit network is laid on the gravel layer, wherein the casting conduit network is formed by a plurality of first conduits and a second conduit, the first conduit being a full-length conduit and having a length greater than that of the second conduit; when laying the conduit network, a plurality of first conduits are laid side by side and spaced apart on the gravel layer, The second conduit is inserted and laid side by side between two adjacent first conduits, and one end of the first conduit and the second conduit is exposed to a predetermined length outside the filling end respectively; a plurality of slurry holes are pierced in the circumferential surface of the first conduit and the second conduit along the length direction; a grouting device injects prefabricated mixed slurry into the filling layer in the abutment roadbed through the first conduit and the second conduit; the prefabricated mixed slurry flowing into the filling layer from the slurry holes is bonded with the gravel layer and the fluid sandy soil phase; the above-mentioned filling and slurry pouring process is repeated until the top surface of the roadbed is filled to form the abutment roadbed of the bridge and culvert.

[0022] Among them, sandy soil has voids, and liquid may remain in the voids, which can easily cause an impact during construction. The sandy soil can be subjected to vibration loading treatment through a vibrator to remove moisture in the pores of the sandy soil, enhance the density and shear strength of the filler, and thus reduce the liquefaction risk of the bridge and culvert abutments obtained based on the filler; the filler after filling is leveled and compacted to obtain a filler layer, which can make the filler layer reach the flatness and stability required by the design, and then an excavator and other equipment can be used to perform preliminary leveling on the filler, remove large height differences and potholes, and make the filler surface flat, and use a compacting machine to compact the filler to increase the density and stability of the filler; the casting conduit consists of two conduits, which can facilitate the injection of prefabricated slurry into the filler layer.

[0023] The construction method for pouring a highway bridge and culvert abutment roadbed based on fluidized sandy soil provided in an embodiment of the present invention fills the road-bridge transition zone layer by layer. After filling a layer of filler, prefabricated slurry is injected into the filler through a pouring conduit to obtain a dense abutment layer of expansive consolidated sandy soil. In this way, by repeatedly constructing the abutment layer until it is filled to the top surface of the roadbed, the bridge and culvert abutment obtained can reduce the risk of vehicle jumping at the bridge head caused by filler settlement.

[0024] In some embodiments, the prefabricated mixed slurry that flows into the filler layer from the slurry holes is bonded with the gravel layer and the fluid sandy soil, including: using calcium hydroxide generated by the reaction of the prefabricated mixed slurry to react with carbon dioxide in the fluid sandy soil to generate calcium carbonate, so as to enhance the stability of the filler layer after bonding; wherein calcium hydroxide reacts with carbon dioxide to form calcium carbonate, and calcium carbonate is insoluble in water compared to calcium hydroxide, thereby protecting the stability of the overall structure in a humid environment.

[0025] In some embodiments, a plurality of slurry holes are penetrated on the circumferential surfaces of the first conduit and the second conduit along the length direction, including: a plurality of slurry holes with a diameter of 10 mm are penetrated on the circumferential surface of the first conduit along the length direction, and a distance of 1 m is reserved from the outermost slurry holes at both ends in the length direction to the filling end and the filling end respectively; a plurality of 10 mm slurry holes are penetrated on the circumferential surface of the second conduit at intervals of 30 cm in the length direction; wherein, the closer the distance between the filler layer and the top surface of the roadbed is, the greater the pressure on the back layer obtained based on the filler layer is. In order to increase the anti-subsidence property, the thickness of the filler layer is 100 mm.

[0026] In some embodiments, the second conduit is inserted side by side and laid between two adjacent first conduits, and two second conduits are arranged axially at intervals, and the positions of the slurry holes of the second conduit correspond to the outer pipe sections of the outermost slurry holes at both ends of the first conduit.

[0027] In some embodiments, the grouting equipment injects prefabricated mixed slurry into the filler layer in the back-mounted roadbed through a first conduit and a second conduit, including: injecting prefabricated slurry into the middle area of ​​the filler layer through the first conduit; using the slurry holes on the first conduit to first wet the middle area of ​​the filler, and using a closed pipe section without slurry holes at a distance of 1m from the first conduit to the filling end and the filling end respectively to prevent the slurry from overflowing from both ends; injecting prefabricated slurry into the edge area of ​​the filler layer through the second conduit; using the second conduit to inject slurry into the edge area of ​​the filler to wet the edge part of the filler.

[0028] In some embodiments, before the grouting equipment injects the prefabricated mixed slurry into the filling layer in the back roadbed through the first conduit and the second conduit, the method also includes: marking a water level line on the mixing tank to control the amount of prepared slurry; adding the following components in parts by weight to the mixing tank, water, 0.8; cement, 1; high fluidity agent 0.04; after adding each component to the mixing tank, before filling, continuously stirring to obtain the prefabricated slurry; wherein, the water level line is drawn in order to determine the amount of water used according to the water level, so as to facilitate the control of the amount of slurry used; the required materials include water, cement and high fluidity agent, preferably in a ratio of water, 0.8; cement, 1; high fluidity agent, 0.04, and a suitable ratio can also be selected according to the actual conditions on site; wherein the high fluidity agent is used to make the prepared prefabricated slurry have better fluidity, for example, a fluidity of 210mm~230mm.

[0029] It should be clear that after adding each component into the mixing tank and stirring to obtain the prefabricated slurry, the prefabricated slurry should be stirred continuously before filling. This can prevent the precipitation of some components in the prefabricated slurry, ensure the slurry quality, and reduce the risk of filler sedimentation.

[0030] In some embodiments, the trial compressive strength standard of the precast slurry is: Rs ≥ 1.05Rb; wherein Rs is the trial compressive strength of the precast slurry, and Rb is the design compressive strength of the precast slurry; in this way, by controlling the trial compressive strength of the precast slurry, the compressive strength of the bridge and culvert abutment backing obtained based on the precast slurry and filler can be ensured, thereby reducing the risk of filler settlement.

[0031] In some embodiments, the fluidity of the prefabricated slurry is 210 mm to 230 mm; in this way, the prefabricated slurry can be injected into the middle area of ​​the packing layer along the through-length conduit, and the prefabricated slurry can be evenly distributed in the packing layer, thereby reducing the risk of packing sedimentation.

[0032] In some embodiments, the grouting equipment injects prefabricated mixed slurry into the filling layer in the back-of-platform roadbed through the first conduit and the second conduit, including: controlling the pouring pressure to 0.5~0.8Mpa, and injecting the prefabricated slurry into the filling layer through the first conduit and the second conduit; when the pouring pressure is 1.2~1.5Mpa, performing a pressure stabilization operation, and completing the injection of the prefabricated slurry after 0.8~1.2 minutes of pressure stabilization; wherein, while ensuring that the prefabricated slurry injected through the pouring conduit can fully penetrate into the pores of the sandy soil particles in the central area of ​​the filling layer, the impact of the prefabricated slurry injected through the pouring conduit on the surrounding structure can be reduced.

[0033] In addition, in the process of injecting prefabricated slurry into the filling layer through the pouring conduit, the pouring pressure will increase with the increase of pouring speed and be monitored by the pouring pressure gauge. Therefore, both the pouring speed and the pouring pressure need to be controlled. Too fast a pouring speed will cause voids and separation after pouring, while too slow a pouring speed will affect the construction efficiency. At the same time, good pouring pressure can prevent the loss of pouring materials.

[0034] In some embodiments, the horizontal deviation and vertical deviation of the casting conduit are no more than 10 cm; wherein the vertical deviation refers to the vertical spacing deviation of the conduit; in this way, the casting conduit can be evenly arranged on the filler layer, thereby facilitating the uniform injection of the preset slurry into the filler layer and reducing the risk of filler settlement.

[0035] It should be noted that, in this article, relational terms such as first and etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0036] Each embodiment in this specification is described in a related manner, and the same or similar parts between the embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0037] In particular, for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0038] For the convenience of description, the above device is described by dividing the functions into various units / modules. Of course, when implementing the present invention, the functions of each unit / module can be implemented in the same or multiple software and / or hardware.

[0039] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A construction method for pouring a highway bridge and culvert abutment back roadbed based on fluid sandy soil, characterized in that: include: Select fluid sandy soil as the back-platform roadbed filler, and after cleaning the surface of the roadbed foundation pit, use the filler to backfill the back-platform roadbed foundation pit in layers; wherein, after the bottom layer is filled, the filler is leveled and compacted; Lay a layer of gravel on the bottom filler layer and level it to form a gravel layer; Laying a casting conduit network on the gravel layer, wherein the casting conduit network is formed by a plurality of first conduits and second conduits, wherein the first conduits are through-length conduits and are longer than the second conduits; When laying the conduit network, a plurality of first conduits are laid side by side and at intervals on the gravel layer, the second conduits are inserted and laid side by side between two adjacent first conduits, and one end of the first conduit and the second conduit are respectively exposed outside the filling end by a predetermined length; A plurality of slurry holes are formed on the circumferential surfaces of the first conduit and the second conduit along the length direction; The grouting equipment injects the prefabricated mixed slurry into the filler layer in the back of the platform roadbed through the first conduit and the second conduit; The prefabricated mixed slurry flowing from the slurry holes into the filler layer is bonded with the gravel layer and the fluid sandy soil phase; Repeat the above-mentioned process of filling and pouring slurry until the top surface of the roadbed is filled to form the bridge and culvert abutment back roadbed.

2. The construction method for pouring highway bridge and culvert abutment back roadbed based on fluid sandy soil according to claim 1 is characterized in that: The prefabricated mixed slurry flowing into the filler layer from the slurry holes is bonded with the gravel layer and the fluid sandy soil, including: using the calcium hydroxide generated by the reaction of the prefabricated mixed slurry to react with the carbon dioxide in the fluid sandy soil to generate calcium carbonate, so as to enhance the stability of the filler layer after bonding.

3. The construction method for pouring highway bridge and culvert abutment back roadbed based on fluid sandy soil according to claim 1 is characterized in that: The plurality of slurry holes penetrating the circumferential surfaces of the first conduit and the second conduit along the length direction comprises: A plurality of slurry holes with a diameter of 10 mm are drilled in the circumferential surface of the first conduit along the length direction, and a distance of 1 m is reserved from the outermost slurry holes at both ends to the filling end and the filling end respectively; A plurality of 10 mm slurry holes are provided on the circumferential surface of the second conduit at intervals of 30 cm along the length direction.

4. The construction method for pouring highway bridge and culvert abutment back roadbed based on fluid sandy soil according to claim 3 is characterized in that: The second conduits are inserted side by side and laid between two adjacent first conduits, and two second conduits are arranged axially at intervals, and the positions of the slurry holes of the second conduits correspond to the outer pipe sections of the outermost slurry holes on both ends of the first conduits.

5. The construction method for pouring highway bridge and culvert abutment back roadbed based on fluidized sandy soil according to claim 3 or 4, characterized in that: The grouting equipment injects the prefabricated mixed slurry into the filler layer in the back-of-platform roadbed through the first conduit and the second conduit, comprising: injecting prefabricated slurry into the middle area of ​​the filler layer through the first conduit; The slurry holes on the first conduit are used to wet the middle area of ​​the filler first, and the closed pipe sections without slurry holes are used to prevent the slurry from overflowing from both ends. injecting prefabricated slurry into the edge area of ​​the filler layer through the second conduit; The slurry is injected into the edge area of ​​the filler by using the second conduit, so that the edge part of the filler is infiltrated.

6. The construction method for pouring highway bridge and culvert abutment back roadbed based on fluid sandy soil according to claim 1 is characterized in that: Before the grouting equipment injects the prefabricated mixed slurry into the filler layer in the back-of-platform roadbed through the first conduit and the second conduit, the method further comprises: A water level line is carved on the mixing tank to control the amount of slurry prepared; Add the following components in parts by weight into the mixing tank: water, 0.8; cement, 1; high flow agent, 0.04; After adding various components into the stirring tank, stirring is continued before filling to obtain prefabricated slurry.

7. The construction method for pouring highway bridge and culvert abutment back roadbed based on fluid sandy soil according to claim 1 is characterized in that: The test compressive strength standard of the prefabricated slurry is: Rs ≥ 1.05Rb; Among them, Rs is the trial compressive strength of the prefabricated slurry, and Rb is the designed compressive strength of the prefabricated slurry.

8. The construction method for pouring highway bridge and culvert abutment back roadbed based on fluid sandy soil according to claim 1 is characterized in that: The fluidity of the prefabricated slurry is 210 mm to 230 mm.

9. The construction method for pouring highway bridge and culvert abutment back roadbed based on fluid sandy soil according to claim 1 is characterized in that: The grouting equipment injects the prefabricated mixed slurry into the filler layer in the back-of-platform roadbed through the first conduit and the second conduit, comprising: Controlling the pouring pressure to 0.5-0.8 MPa, and injecting the prefabricated slurry into the filler layer through the first conduit and the second conduit; When the pouring pressure is 1.2~1.5Mpa, the pressure stabilization operation is carried out. After 0.8~1.2 minutes of pressure stabilization, the injection of the prefabricated slurry is completed.

10. The construction method for pouring highway bridge and culvert abutment back roadbed based on fluid sandy soil according to claim 1, characterized in that: The horizontal deviation and vertical deviation of the casting conduit are both no greater than 10 cm.

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