Riverbank revetment construction method

Abstract

A riverbank revetment construction method, comprising the following steps: along a riverbank revetment, laying a composite structure consisting of alternating long piles and short piles, each long pile being divided into two parts, one part being independent, and the other part combining with a short pile to form a composite pile; using a static pressing method to press the independent part of the long pile into a laying position along the riverbank revetment, then pressing the composite pile onto the independent part of the long pile, and connecting the long pile part of the composite pile to the already-pressed independent part of the long pile to form a whole; on the side of the short pile, continuing to statically press the independent part of another long pile, and during the process, using a limiting structure between the short pile and the independent part of the long pile for limited pressing thereof; repeating the process in the laying direction of the riverbank revetment, so as to press the composite structure consisting of the long piles and the short piles; and replacing soil enclosed by the short pile within each composite pile with a replacement material which is a material having water permeability. The riverbank revetment construction method has the advantages of simple structure, good mechanical property, convenient construction and excellent soil retaining property and water permeability.

Description

River bank protection construction method Technical Field

[0001] The invention relates to the technical field of hydraulic engineering structures, in particular to a river bank protection construction method. Background Art

[0002] Bank protection piles are widely used in inland waterway upgrades and river regulation projects. Prefabricated structures, such as sheet piles and U-shaped piles, are a popular method for river bank protection. However, traditional sheet piles rely on concrete mortises and tenons, a form of jointed fit that is significantly affected by construction quality and exhibits poor soil retention.

[0003] The current river bank protection piles also use pile-plate type, that is, a corbel is set behind the pile, the pile foundation is constructed first, and then the protection plate is constructed. Between the piles and plates, the drainage effect behind the wall is poor, the water pressure behind the wall is high, and the safety factor behind the wall is low. Summary of the Invention

[0004] The purpose of the present invention is to provide a river bank protection construction method based on the above-mentioned deficiencies of the existing technology, which realizes the construction of river bank protection through the combination of concrete sheet piles and composite sheet piles, while improving soil retention and water permeability.

[0005] The purpose of the present invention is achieved by the following technical solutions:

[0006] A river bank protection construction method, characterized in that the construction method comprises the following steps:

[0007] A composite structure consisting of alternating long and short piles is laid out along the river bank, wherein the long piles are divided into two parts, one of which is independent and the other forms a composite pile with the short piles;

[0008] The independent part of the long pile is pressed into the river bank protection layout position by using a static pressure method, and then the composite pile is pressed into the independent part of the long pile, and the long pile part of the composite pile is connected with the independent part of the long pile that has been pressed into to form a whole;

[0009] Continue statically pressing the independent part of another long pile on one side of the short pile, and during this process, use the limiting structure between the short pile and the independent part of the long pile to limit and press them in;

[0010] In this reciprocating manner, the combined structure of the long piles and the short piles is pressed in along the layout direction of the river bank protection;

[0011] The soil surrounded by the short piles in each composite pile is replaced with a material having certain water permeability.

[0012] The long piles are concrete sheet piles, and the short piles are steel sheet piles, wherein the combined piles are composed of concrete sheet pile segments and steel sheet pile segments, wherein the steel sheet pile segment is arranged on one side of the concrete sheet pile segment and includes two spaced steel plates.

[0013] The corresponding net width ratio of the concrete sheet piles to the steel sheet piles is 1.0-1.2.

[0014] The concrete sheet pile has a rectangular cross-section and a length-to-width ratio of 1.5-2.0; the ratio between the embedded length and the exposed length of the concrete sheet pile is 2:1.

[0015] The distance between the two steel plates of the steel sheet pile is 20-30 cm, and the ratio between the embedded length and the exposed length is 0.3:1.

[0016] The long pile portion of the combined pile is provided with a groove matching the short pile, and the independent portion of the long pile can be limited by inserting the short pile into the groove.

[0017] Drain holes are opened on the steel plate, geotextiles are arranged at the drainage holes, and at the same time, graded crushed stones wrapped with geotextiles are replaced at the two layers of short piles.

[0018] A cap beam is constructed above the combined structure formed by staggering the long piles and the short piles to connect the piles into one, wherein the short piles are embedded in the cap beam.

[0019] The advantages of the present invention are simple structure, good mechanical properties, convenient construction, and excellent soil retention and water permeability. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG1 is an elevational view of the present invention;

[0021] FIG2 is a plan view of the present invention;

[0022] FIG3 is a planar structural diagram of the present invention;

[0023] FIG4 is a detailed structural diagram of the facade of the present invention;

[0024] FIG5 is a diagram showing the connection structure of the present invention. DETAILED DESCRIPTION

[0025] The features of the present invention and other related features are further described in detail below through embodiments in conjunction with the accompanying drawings to facilitate understanding by those skilled in the art:

[0026] As shown in Figure 1-5, the marks in the figure respectively represent: concrete sheet pile segment 1, steel sheet pile segment 2, excavated riverbed mud surface position 3, concrete sheet pile 4, groove 11, concrete pile outer wall 12, concrete pile inner wall 13, rubber waterstop 14, drainage hole 21, geotextile 22, steel bar hole 23, connecting shear nail 24, connecting short steel bar 25, graded sand and gravel 26.

[0027] Example: As shown in Figures 1 to 5, this embodiment of the riverbank construction method constructs a composite structure composed of composite sheet piles and concrete sheet piles 4. The composite sheet piles are composed of concrete sheet pile segments 1 and steel sheet pile segments 2. After construction, the concrete sheet pile segments 1 (as components) and the concrete sheet piles 4 (as independent components) form long piles, while the steel sheet pile segments 2 serve as short piles. This creates a structure of interlaced long and short piles arranged along the riverbank. The long piles primarily provide stability to the revetment retaining structure through embedment, while the short piles form retaining and drainage structures to improve water permeability.

[0028] The concrete sheet pile segment 1 and the steel sheet pile segment 2 are prefabricated to form a monolithic structure, with the concrete sheet pile segment 1 slightly protruding from the steel sheet pile segment 2. The concrete sheet pile segment 1 is a hollow rectangular structure with an outer concrete pile wall 12 and an inner concrete pile wall 13. This reduces construction costs while ensuring sufficient structural strength and stability. Two rows of grooves 11 are prefabricated on one side of the concrete sheet pile segment 1 in the width direction, while the other side of the width direction is formed by the two steel plates of the steel sheet pile segment 2. The two rows of grooves 11 mate with the two steel plates, allowing the steel plates to be inserted into the grooves 11.

[0029] As shown in Figures 1 and 2, when several composite sheet piles are combined, the steel sheet pile segment 2 in one composite sheet pile is inserted into the groove 11 provided on the concrete sheet pile segment 1 in another adjacent composite sheet pile, so that the pile foundations are engaged along the revetment direction to form an integral structure.

[0030] In this embodiment, a vertically arranged rubber waterstop 14 is provided inside the groove 11 to enable the concrete sheet pile segment 1 to form surface contact with the steel sheet pile segment 2, thereby achieving the effect of retaining soil at the engagement portion of the pile foundation.

[0031] As shown in Figures 3 to 5, the connection points between the concrete sheet pile segments 1 and the steel sheet pile segments 2 are prefabricated with several connecting shear nails 24. These connecting shear nails 24 are evenly spaced along the length of the pile to improve the connection between the concrete sheet pile segments 1 and the steel sheet pile segments 2. During use, the connecting shear nails 24 are welded to the steel plates of the steel sheet pile segments 2 and embedded within the concrete sheet pile segments 1 during prefabrication.

[0032] The concrete sheet piles 4 are arranged below the composite sheet piles and correspond to the positions of the concrete sheet pile segments 1 . The concrete sheet piles 4 are fixedly connected to the concrete sheet pile segments 1 to form an integral structure.

[0033] As shown in Figures 3 and 4 , drainage holes 21 are arranged on the steel plates on either side of the steel sheet pile segment 2. Geotextile fabric 22 is attached to the steel plates at the locations of the drainage holes 21 to retain soil. A certain distance is left between the two layers of steel plates in the steel sheet pile segment 2. After driving, the geotextile-wrapped fill is replaced with graded sand and gravel 26 to improve the drainage performance of the sheet pile.

[0034] As shown in Figures 4 and 5 , a number of rebar holes 23 are provided at the top of the steel sheet pile segment 2. These holes are arranged in an array. When a crown beam is constructed on top, short connecting rebars 25 passing through these holes are inserted into the crown beam to form an integrated structure. The crown beam further reinforces and connects the multiple composite sheet piles to form an integrated structure. The crown beam can be prefabricated or cast-in-place.

[0035] During construction, this embodiment includes the following construction steps:

[0036] 1) Using the static pressure method, concrete sheet piles 4 are pressed into position according to the layout of the river bank protection. Subsequently, a composite sheet pile consisting of concrete sheet pile segments 1 and steel sheet pile segments 2 is pressed into the top of the concrete sheet piles 4. The concrete sheet pile segments 1 are connected to the pressed concrete sheet piles 4 to form a whole.

[0037] 2) Continue statically pressing another concrete sheet pile 4 on one side of the steel sheet pile segment 2. During this process, the already pressed steel sheet pile segment 2 is used as a positioning reference for pressing the new concrete sheet pile 4. That is, the groove of the newly pressed concrete sheet pile 4 is inserted into the steel sheet pile segment 2. At this time, the newly pressed concrete sheet pile 4 can be guided by the already pressed steel sheet pile segment 2 to ensure its verticality. As the new concrete sheet pile 4 is pressed in, it gradually separates from the steel sheet pile segment 2 and is accurately pressed into the predetermined position.

[0038] After completion, a new composite sheet pile is pressed in above the new concrete sheet pile 4 using the same positioning and guiding method to ensure the concentricity between the two and improve the bank protection and retaining effect.

[0039] 3) In this reciprocating manner, the soil sheet pile segments 1 and the steel sheet pile segments 2 are pressed in along the layout direction of the river bank protection to form the combined sheet piles and the concrete sheet piles 4.

[0040] 4) After the construction is completed, the original soil between the two steel plates of the steel sheet pile segment 2 is excavated and replaced with graded sand mixed with crushed stone 26 to improve the soil retention and drainage effect.

[0041] The net width ratio (excluding connection width) of concrete sheet piles to steel sheet piles is between 1.0 and 1.2. This ratio facilitates fabrication and transportation. Furthermore, concrete sheet piles primarily provide embedded stability. If the ratio is too small, there is a risk of instability or the need for additional structural measures. If the steel sheet piles are too wide, there is a risk of buckling and instability in the steel sheet, or the thickness of the steel sheet may be increased, resulting in uneconomical results. Therefore, the ratio of concrete sheet piles to steel sheet piles is set at 1.0 to 1.2.

[0042] Concrete sheet piles have a rectangular cross-section with an aspect ratio of 1.5-2.0. This ratio is wider on the waterfront side. A too large aspect ratio results in excessive flexibility and displacement, while a too small ratio results in a high number of joints, increasing construction errors. A 1.5-2.0 aspect ratio reduces the number of joints while ensuring sheet pile rigidity, making it easier to manufacture and transport. Generally, the length of the pile is three times the length of the exposed portion, a typical cantilever pile with a 2-to-1 ratio. This means that the length of the pile above the excavated riverbed mud level is 1 / 3 of the total length, while the length of the pile below the excavated riverbed mud level is 2 / 3 of the total length. This ratio can also be determined based on geological conditions. Concrete sheet piles are used to provide embedded stability.

[0043] The length of the steel sheet pile is generally 1.3 times the length of the exposed surface, resulting in a 0.3 embedment to 1 leakage ratio. This configuration generally ensures stable seepage in the bottom soil under conditions of front-to-rear water level differences while also meeting the requirements of retaining soil. If necessary, the embedment ratio of the steel sheet pile should be determined based on the extreme water level difference to ensure stable seepage and prevent soil flow damage.

[0044] Although the above embodiments have described in detail the concepts and embodiments of the present invention with reference to the accompanying drawings, ordinary technicians in this field can recognize that various improvements and modifications can still be made to the present invention without departing from the scope of the claims, so they are not described in detail here.

Claims

1. A river bank protection construction method, characterized in that: The construction method comprises the following steps: A combined structure consisting of staggered long piles and short piles is laid out along the river bank, wherein the long piles are divided into two parts, one of which is independent and the other forms a combined pile with the short piles; The independent part of the long pile is pressed into the river bank protection layout position by static pressure method, and then the composite pile is pressed into the independent part of the long pile, and the long pile part of the composite pile is connected with the independent part of the long pile that has been pressed into a whole; Continue statically pressing the independent part of another long pile on one side of the short pile, and in this process, use the limiting structure between the short pile and the independent part of the long pile to limit and press them in; In this way, the combined structure of the long piles and the short piles is pressed in along the layout direction of the river bank protection; The soil surrounded by the short piles in each composite pile is replaced with a material having certain water permeability.

2. A river bank protection construction method according to claim 1, characterized in that: The long piles are concrete sheet piles, and the short piles are steel sheet piles, wherein the combined piles are composed of concrete sheet pile segments and steel sheet pile segments, wherein the steel sheet pile segment is arranged on one side of the concrete sheet pile segment and comprises two spaced-apart steel plates.

3. A river bank protection construction method according to claim 2, characterized in that: The corresponding net width ratio of the concrete sheet piles to the steel sheet piles is 1.0-1.

2.

4. A river bank protection construction method according to claim 2, characterized in that: The concrete sheet pile has a rectangular cross section with a length-to-width ratio of 1.5-2.0; the ratio between the embedded length and the exposed length of the concrete sheet pile is 2:

1.

5. A river bank protection construction method according to claim 2, characterized in that: The distance between the two steel plates of the steel sheet pile is 20-30 cm, and the ratio between the embedded length and the exposed length is 0.3:

1.

6. A river bank protection construction method according to claim 1, characterized in that: The long pile portion of the combined pile is provided with a groove matching the short pile, and the independent portion of the long pile can be limited by inserting the short pile into its groove.

7. A river bank protection construction method according to claim 1, characterized in that: Drain holes are opened on the steel plate, geotextiles are arranged at the drainage holes, and graded crushed stones wrapped with geotextiles are replaced at the two layers of short piles.

8. A river bank protection construction method according to claim 1, characterized in that: A cap beam is constructed above the combined structure formed by the staggered long piles and the short piles to connect the piles into one, wherein the short piles are embedded in the cap beam.

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