An assembled low pile cap bank protection suitable for silt foundation and construction method

Abstract

An assembled low pile cap revetment suitable for silt foundation includes a pile foundation and a prefabricated base plate. The prefabricated base plate is provided with a plurality of base plate openings, the pile head passes through the base plate openings, the prefabricated base plate is mounted on the pile foundation corbel, the side grooves of the pile head are located above the prefabricated base plate, fasteners are installed at the grooves on both sides of the pile head, the fasteners are L-shaped, the outward protrusions of the lower part of the fasteners form fastener tenons, the fastener tenons are tightly fitted with the side grooves of the pile head, the bottom of the fasteners is against the base plate, the pile head kit is sleeved on the pile head and the outer periphery of the fasteners, forming an effective connection between the prefabricated pile foundation and the prefabricated base plate. The assembled low pile cap revetment structure of the present invention is reliable, the components can be orderly dismantled according to demand, no waste concrete is left in the soil, and the impact on the ecology is reduced. It is prefabricated according to factory standards, with low cost and good versatility, completely avoiding the on-site cast-in-place concrete construction steps, shortening the on-site construction period, good construction quality, and less environmental impact.

Description

Technical Field

[0001] The invention relates to the technical field of river engineering construction, and discloses an assembled low-pile cap bank protection suitable for a muddy foundation and a construction method. Background Art

[0002] When constructing bank protection projects on rivers, there is often a large height difference between the riverbed and the land behind, and little space for slope reduction. It is necessary to build upright bank protection sections or composite bank protection sections. When constructing upright bank protection structures on silt foundations with poor mechanical indicators, foundation treatment or the use of deep foundation structures is required to ensure structural safety and stability requirements.

[0003] Conventional upright revetments or composite revetments include gravity retaining wall structures, pile foundation retaining wall structures, etc. Building a new gravity retaining wall structure on a foundation with deep silt and poor bearing capacity requires large-scale foundation treatment, which is not economical compared to pile foundation structures. Conventional pile foundation retaining wall construction often requires cast-in-place concrete components below the water level, with a large construction interface and a long construction period. It also requires the construction of cofferdams to occupy the river for a long time. This affects the navigation and flood discharge functions of the river. Therefore, it is urgent to explore an assembled revetment and construction method suitable for silt foundations. Summary of the invention

[0004] The purpose of the present invention is to propose an assembled low-pile cap revetment and construction method suitable for muddy foundation, which can overcome the limitations of conventional revetment forms in the application of river channels with muddy foundations and realize the factory-based construction of river channel revetment projects. It can also flexibly modify the direction of the local river channel during use, and realize the recycling of components when the river channel revetment is modified again.

[0005] In order to solve the above technical problems, the present invention is solved by the following technical solutions:

[0006] An assembled low pile cap revetment suitable for muddy foundation, characterized in that: the assembled low pile cap revetment comprises a pile foundation inserted into the soil, a pile head is provided on the top of the pile foundation, grooves are provided on both sides of the upper part of the pile head, a pile foundation corbel is provided below the pile head, the foundation trench is excavated to the same elevation as the top of the pile foundation corbel and leveled, a plurality of bottom plate openings are provided on the prefabricated bottom plate, the prefabricated bottom plate is placed horizontally, the pile head passes through the bottom plate openings, the prefabricated bottom plate is erected on the pile foundation corbel, and the soil below the prefabricated bottom plate is ensured to be stable. The body is full and dense, so that the soil under the precast base plate and the pile foundation can jointly exert bearing capacity to bear the upper load; the groove on the side of the pile head is located above the precast base plate, and fasteners are installed in the grooves on both sides of the pile head. The fasteners are L-shaped, and the outward protrusions at the bottom of the fasteners form fastener tenons. The fastener tenons fit tightly with the grooves on the side of the pile head, and the bottom of the fasteners is against the base plate. The pile head kit is sleeved on the periphery of the pile head and the fasteners, so that the three form a whole, locking the pile head on the precast base plate, forming an effective connection between the precast pile foundation and the precast base plate.

[0007] Furthermore, multiple layers of eco-frames are stacked on top of the prefabricated base plate to form a retaining wall, and soil is backfilled behind the retaining wall. The number of eco-frame layers is reasonably set according to different retaining requirements.

[0008] Furthermore, an upper flange extending upward and a lower flange extending downward are provided at the front of the prefabricated bottom plate, the front wall of the ecological frame abuts against the upper flange of the prefabricated bottom plate, and the lower flange of the prefabricated bottom plate is inserted into the soil.

[0009] Furthermore, when the number of eco-frame layers is more than 4, geogrids are arranged between the eco-frames to bond with the soil behind them and maintain stability.

[0010] Furthermore, geotextile is laid in the ecological frame, and planting soil is backfilled, and water plants are planted in the ecological frame.

[0011] Furthermore, turf is planted on the slope above the retaining wall to protect the slope, and emergent plants are planted on the beach in front of the retaining wall.

[0012] Furthermore, the assembled low-pile cap revetment of the present invention is suitable for use in a river channel where the elevation of the rear land is higher than the designed high water level of the river channel.

[0013] A construction method for assembled low pile cap revetment suitable for muddy foundation, characterized in that the construction method comprises the following steps:

[0014] A. Make pile foundation, prefabricated bottom plate, fasteners and pile head kits. The top of the pile foundation is provided with a pile head, and grooves are provided on both sides of the upper part of the pile head. A pile foundation corbel is provided below the pile head. An upper flange and a lower flange are provided at one end of the prefabricated bottom plate. The prefabricated bottom plate is provided with a plurality of bottom plate openings. The fastener is L-shaped, and the outward protrusions at the lower part of the fastener form fastener tenons that match the grooves on both sides of the pile head. The pile head kit is provided with square holes that match the pile head and the fastener;

[0015] B. Excavation of foundation trench: excavation on the river slope to the bottom plate elevation, and leveling of the foundation trench;

[0016] C. Prefabricated pile foundation construction: the pile foundation is driven into the soil according to the designed pile position and elevation;

[0017] D. Prefabricated base plate construction: hoist the prefabricated base plate into place, set the upper and lower flanges of the prefabricated base plate in the forward direction, open the base plate through the pile head, and set the prefabricated base plate on the corbels. Fill the gaps under the prefabricated base plate with soil. Install fasteners in the grooves on both sides of the pile head. The fastener tenons fit tightly with the grooves on the sides of the pile head. The bottom of the fastener abuts against the base plate. The pile head kit is placed on the periphery of the pile head and the fastener to form a whole, locking the pile head on the base plate.

[0018] E. Prefabricated ecological frame construction: Place the prefabricated ecological frame on the prefabricated bottom plate to form a retaining wall. The front wall of the bottom prefabricated ecological frame is against the upper flange of the front part of the prefabricated bottom plate. Put the pile heads of the front row of pile foundations and the pile head kit installed on the pile heads into the bottom prefabricated ecological frame, and backfill the soil behind the wall at the same time;

[0019] F. Slope leveling and greening planting.

[0020] Furthermore, after the bank protection project is completed, if it is necessary to connect a newly opened branch river to the river channel, it can be achieved by simply moving the ecological frame.

[0021] Furthermore, when the river bank needs to be rebuilt in the future, the existing bank protection components can be dismantled in an orderly manner without leaving waste concrete in the soil.

[0022] The present invention has the following beneficial effects due to the adoption of the above technical solution:

[0023] 1. The assembled revetment is assembled from standard prefabricated pile foundations, prefabricated base plates, and ecological frame retaining walls. It adopts effective connections to meet the requirements of retaining and bearing capacity, and the structure is safe and reliable.

[0024] 2. The ecological frame is a hollow component. While maintaining the stability of the soil behind the wall, it maintains the communication between the open channel and the groundwater body. At the same time, the ecological frame can be planted in layers to adapt to greening under different water levels, which has good ecological properties.

[0025] 3. The revetment project is composed of various components. Eco-frames of different layers can be set to meet different retaining height requirements. After the revetment project is completed, if a new branch river needs to be connected to the river channel, it can be realized by simply moving the eco-frame.

[0026] 4. When the river bank needs to be rebuilt in the future, the existing bank protection components can be dismantled in an orderly manner, and no waste concrete will be left in the soil, reducing the impact on the ecology.

[0027] 5. The bank protection components are prefabricated according to factory standards to achieve large-scale production. They are low-cost and versatile, completely avoiding the on-site cast-in-place concrete construction steps, shortening the on-site construction period, with good construction quality and less environmental impact.

[0028] 6. The on-site installation of bank protection components does not require strict dry land construction conditions and can even be constructed underwater, avoiding the long-term occupation of the river channel by the construction of cofferdams, which would affect river navigation and flood discharge. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention will be further described below in conjunction with the accompanying drawings:

[0030] Figure 1It is a cross-sectional view of the assembled low pile cap revetment applicable to the muddy foundation and the assembled revetment in the construction method of the present invention;

[0031] Figure 2 It is a pile position arrangement diagram on the prefabricated bottom plate of the present invention;

[0032] Figure 3 It is a structural schematic diagram of the prefabricated square piles in the present invention;

[0033] Figure 4 It is a structural schematic diagram of the prefabricated pile head fastener in the present invention;

[0034] Figure 5 It is a structural schematic diagram of the prefabricated pile head kit in the present invention;

[0035] Figure 6 It is a schematic diagram of the deformation of the assembled bank protection at the point where the middle branch river joins the river channel in the present invention.

[0036] In the figure: 1-prefabricated square piles; 2-prefabricated pile head fasteners; 3-prefabricated pile head kits; 4-prefabricated base plates; 5-prefabricated ecological frames; 6-geotextiles; 7-pedestrian walkways; 8-railings; 9-bottom plate openings; 10-grass slope protection; 11-waterfront plants; 12-emergent plants; 13-riverbed slopes; 14-slopes of tributaries perpendicular to the paper surface. DETAILED DESCRIPTION

[0037] The following is a preferred embodiment, and the present invention is described more clearly and completely in conjunction with the accompanying drawings. These embodiments are only used to illustrate the present invention, and are not intended to limit the present invention.

[0038] A prefabricated low-pile cap revetment suitable for silt foundation, characterized in that: the prefabricated low-pile cap revetment comprises a prefabricated square pile 1 inserted into the soil, the prefabricated square pile 1 is provided with a pile head on the top, grooves are provided on both sides of the upper part of the pile head, a pile foundation corbel is provided below the pile head, and a plurality of bottom plate openings are provided on the prefabricated bottom plate, the prefabricated bottom plate 4 is placed horizontally, the pile head passes through the bottom plate openings, the prefabricated bottom plate 4 is erected on the pile foundation corbel, the grooves on the side of the pile head are located above the prefabricated bottom plate 4, and prefabricated pile head fasteners 2 are installed at the grooves on both sides of the pile head, the prefabricated pile head fasteners 2 are L-shaped, and the outward protrusions at the lower part of the prefabricated pile head fasteners 2 form fastener tenons, which are tightly fitted with the grooves on the sides of the pile head, the bottom of the prefabricated pile head fastener 2 is against the prefabricated bottom plate 4, and the prefabricated pile head kit 3 is sleeved on the pile head and the periphery of the prefabricated pile head fastener 2 to form an effective connection between the prefabricated square pile 1 and the prefabricated bottom plate 4.

[0039] like Figure 1As shown, in order to meet the bearing capacity requirements and overall stability requirements for new revetment projects on muddy rivers, low pile cap revetment structures are often used. The assembled low pile cap revetment components are completely prefabricated using factory standards and assembled on site, without the need for on-site cast-in-place concrete. The riverbed slope 13 is excavated and the foundation trench is excavated. The piles are driven by the vibration pile driving method. The prefabricated square piles 1 are driven into the specified elevation and plane pile positions. When they are sunk to the corbels, they can be sunk by combining manual local excavation. The prefabricated base plate 4 is hoisted and installed. With the assistance of construction personnel, the base plate opening 9 is passed through the pile head and mounted on the corbels, and the gaps under the base plate are filled. The prefabricated pile head fasteners 2 and the prefabricated pile head kit 3 are installed to effectively connect the prefabricated square piles 1 and the prefabricated base plate 4. The prefabricated ecological frame 5 is placed according to the requirements of the drawings, with the front wall and the front edge of the prefabricated bottom plate 4 being against each other. The pile heads of the front row of pile foundations and the prefabricated pile head kits 3 thereon are all placed in the prefabricated ecological frame and stacked in order to form a retaining wall. At the same time, the soil behind the retaining wall is backfilled. Geotextile 6 is laid in the prefabricated ecological frame and backfilled with planting soil. The slopes in front and behind the retaining wall are leveled, turf slope protection 10 is planted on the slope above the retaining wall, suitable water-adjacent plants 11 are planted in the ecological frame, and emergent water plants 12 are planted on the beach in front of the wall.

[0040] Eco-frames are stacked on top of the prefabricated bottom plate to form a retaining wall, and the soil is backfilled behind the retaining wall. The number of eco-frame layers is reasonably set according to different retaining requirements. When there are many eco-frame layers, geogrids are set between the eco-frames to maintain stability with the soil behind. Geogrids are not required if there are no more than four layers. If there are more than four layers, geogrids are set between each layer. The length of the geogrid should be calculated. The design technology of the eco-frame is relatively mature, which is not the focus and innovation of this application.

[0041] A construction method for assembled low pile cap revetment, characterized by comprising the following steps:

[0042] (1) Measurement and layout

[0043] According to the design requirements and plane position of the drawings, determine the layout position of the bank protection structure on the river slope, and on this basis, determine the scope and elevation of the slope excavation and make marking lines;

[0044] (2) Foundation trench excavation

[0045] First, excavation is carried out on the river slope to create a construction interface. The excavation method adopts layered excavation, which is carried out by a 0.5m3 backhoe excavator and a 5-ton dump truck, and the earth is transported to the designated area. The foundation pit is leveled to ensure that the excavation elevation is accurate. There is no need for cast-in-place concrete for structural construction, and a small amount of water can be allowed to enter the foundation pit, so there is no need to fill the cofferdam;

[0046] (3) Standard prefabricated pile foundation construction

[0047] Select standard prefabricated square piles of reasonable size according to the requirements of bearing capacity and overall stability of the slope. Use the vibration pile sinking method to sink piles in deep mud foundation conditions. Strictly control the elevation and plane position of the pile foundation. When sinking to the corbel, it can be combined with manual partial excavation to sink to the specified elevation.

[0048] (4) Standard prefabricated base plate construction

[0049] The standard prefabricated base plate is transported to the construction site for hoisting and installation. The prefabricated base plate is a symmetrical component, with no distinction between the front and back sides. The prefabricated base plate is hoisted into place, and with the assistance of construction personnel, the base plate opening is passed through the pile head and placed on the corbel. The gaps under the base plate should be filled. Install the standard prefabricated pile head fasteners and standard prefabricated pile head kit to effectively connect the pile foundation and the base plate;

[0050] (5) Standard prefabricated ecological frame construction

[0051] The standard prefabricated eco-frame is placed according to the requirements of the drawings, with the front wall against the front edge of the bottom plate, and the pile heads of the front row of pile foundations are placed in the frame and stacked in order, and the soil behind the wall is backfilled. If the number of stacked layers is greater than 4, geogrids are set between the upper and lower eco-frames, extending into the rear soil to meet the design requirements. Geotextiles are laid in the eco-frame and backfilled with planting soil;

[0052] (6) Slope leveling and greening planting

[0053] The clay soil is backfilled behind the wall to meet the design requirements. The slopes are leveled before and after the retaining wall, and appropriate greenery is planted.

[0054] like Figure 4 As shown, after the bank protection project is completed, if it is necessary to connect a newly opened branch river on the river channel, it can be achieved by simply moving the ecological frame 5 and connecting the river mouth with a cone slope.

[0055] In the description of the present invention, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0056] Although the specific embodiments of the present invention are described above, it should be understood by those skilled in the art that this is only for illustration and the protection scope of the present invention is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but these changes and modifications all fall within the protection scope of the present invention.

Claims

1. An assembled low pile cap revetment suitable for muddy foundation, characterized by: The assembled low pile cap revetment comprises a pile foundation inserted into the soil, a pile head is arranged on the top of the pile foundation, grooves are arranged on the upper and lower sides of the pile head, a pile foundation corbel is arranged below the pile head, the foundation trench is excavated to the same elevation as the top of the pile foundation corbel and is leveled, a plurality of bottom plate openings are arranged on the prefabricated bottom plate, the prefabricated bottom plate is placed horizontally, the pile head passes through the bottom plate openings, and the prefabricated bottom plate is erected on the pile foundation corbel to ensure that the soil below the prefabricated bottom plate is full and dense, so that the soil below the prefabricated bottom plate and the pile foundation can jointly exert bearing capacity to bear the upper load; the grooves on the side of the pile head are located at Above the prefabricated base plate, fasteners are installed in the grooves on both sides of the pile head. The fasteners are L-shaped, and the outward protrusions at the bottom of the fasteners form fastener tenons. The fastener tenons fit tightly with the grooves on the sides of the pile head, and the bottom of the fasteners is against the base plate. The pile head kit is sleeved over the pile head and the fasteners to form a whole, locking the pile head on the prefabricated base plate to form an effective connection between the prefabricated pile foundation and the prefabricated base plate. Multiple layers of ecological frames are stacked above the prefabricated base plate to form a retaining wall. Backfill the soil behind the retaining wall, lay geotextiles in the ecological frames, backfill with planting soil, and plant water plants in the ecological frames.

2. The assembled low pile cap revetment according to claim 1 is characterized by: An upper flange extending upward and a lower flange extending downward are arranged at the front of the prefabricated bottom plate; the front wall of the ecological frame abuts against the upper flange of the prefabricated bottom plate, and the lower flange of the prefabricated bottom plate is inserted into the soil.

3. The assembled low pile cap revetment according to claim 1 is characterized by: When the number of eco-frame layers is more than 4, geogrids are installed between the eco-frames to bond with the soil behind them and maintain stability.

4. A construction method for assembled low pile cap revetment suitable for muddy foundation, characterized in that The construction method comprises the following steps: A. manufacturing a pile foundation, a prefabricated bottom plate, a fastener and a pile head kit, wherein a pile head is provided on the top of the pile foundation, grooves are provided on both sides of the upper part of the pile head, a pile foundation corbel is provided below the pile head, an upper flange and a lower flange are provided at one end of the prefabricated bottom plate, a plurality of bottom plate openings are provided on the prefabricated bottom plate, the fastener is L-shaped, and the outward protrusions of the lower part of the fastener form fastener tenons that match the grooves on both sides of the pile head, and the pile head kit is provided with square holes that match the pile head and the fastener; B. Excavation of foundation trench: excavation on the river slope to the bottom plate elevation, and leveling of the foundation trench; C. Prefabricated pile foundation construction: the pile foundation is driven into the soil according to the designed pile position and elevation; D. Prefabricated base plate construction: hoist the prefabricated base plate into place, set the upper and lower flanges of the prefabricated base plate in the forward direction, open the base plate through the pile head, and set the prefabricated base plate on the corbels. Fill the gaps under the prefabricated base plate with soil. Install fasteners in the grooves on both sides of the pile head. The fastener tenons fit tightly with the grooves on the sides of the pile head. The bottom of the fastener abuts against the base plate. The pile head kit is placed on the periphery of the pile head and the fastener to form a whole, locking the pile head on the base plate. E. Prefabricated ecological frame construction: Place the prefabricated ecological frame on the prefabricated bottom plate to form a retaining wall. The front wall of the bottom prefabricated ecological frame is against the upper flange of the front part of the prefabricated bottom plate. Put the pile heads of the front row of pile foundations and the pile head kit installed on the pile heads into the bottom prefabricated ecological frame, and backfill the soil behind the wall at the same time; F. Slope leveling and greening planting.

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