Shore-facing composite platform and construction method

Abstract

The invention provides a shore-side composite platform and a construction method.The composite platform comprises a backfill type platform and a steel trestle platform, the backfill type platform is located over a bearing platform and comprises guard piles, steel pipe piles, a grouting consolidation wall and a concrete retaining wall, and the area defined by the guard piles and the concrete retaining wall is backfilled with gravel; pouring a concrete cushion layer at the top of the gravel; the two steel trestle platforms are arranged on the left side and the right side of the bearing platform respectively, and the steel trestle platforms and the backfill type platform are fixed in a lap joint mode. Compared with a traditional bearing platform structure and an adopted construction method, the construction method has the advantages that the building, designing and dismantling processes of a drilling platform can be omitted, a large amount of steel consumption and labor cost can be saved, and good economic benefits are achieved.

Description

Technical Field

[0001] The invention belongs to the field of bridge bank cap and pile foundation construction, and in particular relates to a bank composite platform and a construction method. Background Art

[0002] The terrain locations of bridge pier foundations are diverse, the most common ones are underwater foundations and onshore foundations. A more special type of onshore foundation is the waterfront and shorefront foundation. For large-span cross-river bridges, in order to meet the bridge span requirements, the pier foundations are generally set on the bank slope, that is, the waterfront and shorefront foundation.

[0003] Regarding the construction of the shore pier foundation, the current domestic method of setting up a steel platform is generally used for construction. The construction sequence is to set up a drilling platform → construct bored piles → dismantle the platform → construct a cofferdam → construct a cap → dismantle the cofferdam. The traditional method has a long construction period, a large amount of steel, a high construction cost, and a great impact on the river's ecological environment. Summary of the invention

[0004] In view of this, the present invention aims to propose a shore composite platform and a construction method to solve the problems of long construction period, large steel consumption and high construction cost existing in the construction of traditional shore pier foundations.

[0005] The present invention relates to a shore composite platform and a construction method. First, the shore composite platform is described:

[0006] A shore-side composite platform, comprising a backfill platform and a steel trestle platform, wherein:

[0007] The backfill platform is located directly above the cap, including a protective pile set on one side of the cap facing the road, and steel pipe piles set on the other three sides of the cap, and a grouting consolidation wall and a concrete retaining wall are set inside the steel pipe piles. The concrete retaining wall is cast from the top surface of the grouting consolidation wall. The area enclosed by the protective pile and the concrete retaining wall is backfilled with crushed stones, and a concrete cushion layer is cast on the top of the crushed stones.

[0008] The steel trestle platform is provided with two, which are respectively arranged on the left and right sides of the pedestal. The top elevations of the steel trestle platform and the backfill platform are consistent, and the steel trestle platform and the backfill platform are overlapped and fixed.

[0009] Furthermore, the steel trestle platform and the backfill platform are overlapped by I-beams.

[0010] The above is an explanation of the technical content of the shore composite platform. The following is an explanation of the invention content of the shore composite platform construction method as follows:

[0011] A method for constructing a shore composite platform comprises the following steps:

[0012] S10: According to the setting position of the upper cap on the bank, the protective piles are constructed on the side of the cap facing the road, the surface soil of the bank slope is cleaned, and the backfill platform steps are excavated;

[0013] S20: Grooves are opened along the other three sides of the cap, filled with sand, and steel pipe piles for cofferdams are inserted into the grooves to form a cofferdam with the protective piles;

[0014] S30: Grouting the inner side of the steel pipe pile to the bottom of the cap to consolidate the soil in this area to form a grouting consolidation wall 3;

[0015] S40: Install the retaining wall formwork inside the steel pipe pile, tie the steel bars, pour concrete into the space between the retaining wall formwork and the steel pipe pile to form a concrete retaining wall. After the strength of the concrete retaining wall reaches the requirement, fill the area enclosed by the concrete retaining wall and the protection piles with crushed stones and compact them;

[0016] S50: pour a concrete cushion layer on the top surface of the gravel to form a backfill platform, and use the fishing method to construct the steel trestle platforms on the left and right sides of the cap. When the top elevation of the steel trestle platform is consistent with the top elevation of the backfill platform, overlap the backfill platform and the steel trestle platform to form an integral platform;

[0017] S60: Construction of bored piles on a backfill platform;

[0018] S70: Excavate the foundation pit on the backfill platform, and install the inner support of the cofferdam simultaneously with the excavation downwards of the foundation pit;

[0019] After the foundation pit is excavated, the cofferdam bottom concrete is poured underwater, and the water in the cofferdam is pumped out after the bottom concrete reaches the designed strength;

[0020] S80: After pumping, first clean the inside of the weir and cut off the steel casing of the bored piles, chisel off the pile heads, then tie the cap steel bars and cast the cap; finally, remove the support inside the cofferdam, tie the tower base steel bars, install the formwork, and cast the tower base concrete.

[0021] Furthermore, the steel pipe piles are provided with steel bars and are filled with concrete.

[0022] Furthermore, in step S40, the concrete retaining wall is located above the grouting consolidation wall.

[0023] Furthermore, in step S50, the steel trestle platform is constructed forward by using a crawler crane and a high bank side fishing method.

[0024] Furthermore, in step S50, when the top elevations of the steel trestle platform 6 and the backfill platform are consistent, the steel trestle platform and the backfill platform are connected by overlapping I-beams, and a bridge deck is laid on top.

[0025] Compared with the prior art, the shore-side composite platform and construction method described in the present invention have the following advantages:

[0026] (1) Economic benefits: Compared with the traditional construction method, this construction method can save the design and dismantling process of the drilling platform, save a lot of steel and labor costs, and has good economic benefits.

[0027] (2) Social benefits: The present invention can transfer the construction of bridge pile foundation from the platform to the land, which reduces the construction difficulty and the requirements for construction equipment, improves the construction quality, speeds up the construction efficiency and shortens the construction period. The invention is simple in principle, novel and highly practical, and provides technical reserves and experience accumulation for the construction of similar bridge foundation projects.

[0028] (3) Energy-saving and environmental protection benefits: This construction method can make full use of the terrain conditions of the bank slope, has high stability and structural strength, has little impact on the surrounding water environment and geological environment, and reduces the disturbance and damage to the ecological red line of the Yangtze River. After the construction is completed, the outer retaining wall can be used as a bridge crash pier to protect the bridge abutment from damage caused by ship collision. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0030] Figure 1 This is a schematic diagram of the grouting consolidation at the bottom of the backfill platform;

[0031] Figure 2 This is a schematic diagram of a backfill platform during layered backfilling and compaction;

[0032] Figure 3 This is the main view of the bored piles constructed by rotary drilling after the construction of the composite platform is completed;

[0033] Figure 4 This is the main view of the bored piles constructed by rotary drilling after the construction of the composite platform is completed;

[0034] Figure 5 This is the main view of the composite platform after construction is completed, with gradual excavation and internal support below;

[0035] Figure 6 It is a top view of the gradual excavation and the internal support below after the construction of the composite platform is completed;

[0036] Figure 7 Schematic diagram of the connection between the backfill platform and the steel trestle platform;

[0037] Figure 8 Schematic diagram of the internal reinforcement of the backfill platform steel pipe pile.

[0038] Description of reference numerals:

[0039] 1. Steel pipe piles, 2. Concrete retaining wall, 3. Grouting consolidation wall, 4. Gravel, 5. Concrete cushion, 6. Steel trestle platform, 7. External expansion platform, 8. Road reconstruction construction platform, 9. Protective piles, 10. Pile caps, 11. Steel casing, 12. Cofferdam ring beam, 13. Cofferdam internal support, 14. Bottom concrete, 15. I-beam, 16. Rotary drilling rig, 17. Vibratory roller, 18. Grouting equipment, 19. Main reinforcement, 20. Stirrups, 21. Concrete. DETAILED DESCRIPTION

[0040] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0041] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions 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 cannot be understood as limiting the present invention. In addition, the terms "first", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0042] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0043] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0044] First, the embodiment of the shore composite platform is described:

[0045] A shore-side composite platform includes a backfill platform and a steel trestle platform 6, wherein the backfill platform is located directly above the pedestal, and two steel trestle platforms are provided, one on the left and the other on the right side of the pedestal. Figure 3 , 4As shown, it includes a protective pile 9 set on one side of the foundation facing the road, and steel pipe piles 1 set on the other three sides of the foundation. The soil layer inside the steel pipe pile 1 and close to the steel pipe pile position is grouted to form a grouting consolidation wall 3. A concrete retaining wall 2 is poured above the grouting consolidation wall 3. The area enclosed by the protective pile 9 and the concrete retaining wall 2 is backfilled with gravel 4, and a concrete cushion layer 5 is poured on top of the gravel 4. The steel trestle platform 6 and the backfill platform have the same top elevation, and the steel trestle platform 6 and the backfill platform are overlapped and fixed by I-beams 15.

[0046] In the present invention, the steel pipe pile 1 has a structure as follows Figure 8 As shown, steel bars are arranged inside and concrete 21 is poured therein, wherein the steel bars are a steel cage structure, including a plurality of main bars 19 arranged vertically, the plurality of main bars 19 are evenly arranged in the circumferential direction, and the plurality of main bars 19 are connected and fixed by stirrups 10, thereby improving the tensile strength of the steel pipe pile 1 after the concrete 21 therein is poured.

[0047] In the present invention, according to the needs of on-site construction, the road side of the cap can be transformed into a road reconstruction construction platform 8, and an external expansion platform 7 can be set up on the water side of the cap. The setting of the road reconstruction construction platform 8 and the external expansion platform 7 facilitates the construction of the cap.

[0048] The following is an explanation of the construction method of the shore composite platform in conjunction with an embodiment:

[0049] A method for constructing a shore composite platform comprises the following steps:

[0050] S10: According to the setting position of the upper cap on the bank, a rotary drilling rig 16 is used to construct a protective pile 9 on the side of the cap facing the road, a pile cap 10 is set on the top of the protective pile 9, and then the surface soil of the bank slope is cleaned, and a backfill platform step is excavated;

[0051] S20: Grooves are opened along the other three sides of the cap, the grooves are filled with sand, and cofferdam steel pipe piles 1 are inserted into the grooves to close with the protection piles 9 to form a cofferdam; in this step, steel bars are arranged in the steel pipe piles 1 and concrete is poured;

[0052] S30: Use the grouting equipment 18 to inject grout into the inner side of the steel pipe pile 1 to the bottom of the cap, so that the soil in this area is consolidated to form a grouting consolidation wall 3, such as Figure 1 As shown;

[0053] S40: Install a retaining wall formwork inside the steel pipe pile 1, tie steel bars, form a pouring space between the retaining wall formwork and the steel pipe pile 1, pour concrete into the pouring space to form a concrete retaining wall 2, and after the strength of the concrete retaining wall 2 reaches the required level, backfill gravel 4 layer by layer from the bottom layer of the backfill platform step upwards in the area enclosed by the concrete retaining wall 2 and the protection piles 9, and use a vibrating roller 17 to compact the gravel 4. Figure 2 As shown;

[0054] S50: pouring a concrete cushion layer 5 on the top surface of the crushed stone 4 to form a backfill platform, such as Figure 3 As shown, the steel trestle platform 6 on the left and right sides of the cap is constructed by fishing method. Figure 4 As shown, when the top elevation of the steel trestle platform 6 is consistent with the top elevation of the backfill platform, the backfill platform and the steel trestle platform 6 are overlapped and fixed using I-beams 15, and then the bridge deck is laid on top. Figure 7 As shown, one end of the I-beam 15 is connected and fixed to the steel trestle platform 6, and the other end is embedded in the installation groove opened on the top surface of the backfill platform and fixed by the anchor bolt, so that the backfill platform and the steel trestle platform 6 are connected to form an integral platform;

[0055] S60: Use the rotary drilling rig 16 to construct bored piles on the backfill platform, such as Figure 3 As shown;

[0056] S70: Excavate the foundation pit on the backfill platform, and install the cofferdam internal support simultaneously with the excavation of the foundation pit. Figure 5 , Figure 6 As shown, the inner support of the cofferdam includes a cofferdam ring beam 12 arranged around the cofferdam, and an inner support 13 of the cofferdam connecting the water side and the far water side of the cofferdam, and a cross beam connecting the cofferdam ring beams 12 on adjacent sides, forming a triangular support structure between adjacent side walls of the cofferdam, which works together with the inner support 13 of the cofferdam to improve the support strength of the cofferdam and ensure the safety of foundation pit construction;

[0057] After the foundation pit is excavated, the cofferdam bottom seal concrete 14 is poured underwater, and the water in the cofferdam is pumped out after the bottom seal concrete 14 reaches the designed strength;

[0058] S80: After pumping, first clean the inside of the weir and cut off the steel casing of the bored pile 11, chisel off the pile head, then tie the cap steel bars and cast the cap; finally remove the support inside the cofferdam, tie the tower base steel bars, install the formwork, and cast the tower base concrete.

[0059] In the present invention, in step S50, the steel trestle platform 6 is constructed forward by using a crawler crane and a high bank side fishing method.

[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A shore-side composite platform, characterized in that: It includes a backfill platform and a steel trestle platform (6), wherein: The backfill platform is located directly above the cap, and includes a protective pile (9) arranged on one side of the cap facing the road, a steel pipe pile (1) arranged on the other three sides of the cap, and a grouting consolidation wall (3) and a concrete retaining wall (2) arranged inside the steel pipe pile (1), wherein the concrete retaining wall (2) is cast starting from the top surface of the grouting consolidation wall (3), and the area enclosed by the protective pile (9) and the concrete retaining wall (2) is backfilled with crushed stones (4), and a concrete cushion layer (5) is cast on top of the crushed stones (4); The steel trestle platform (6) is provided with two, which are respectively arranged on the left and right sides of the pedestal. The top elevations of the steel trestle platform (6) and the backfill platform are consistent, and the steel trestle platform (6) and the backfill platform are overlapped.

2. The shore-side composite platform according to claim 1, characterized in that: The steel trestle platform (6) and the backfill platform are overlapped and fixed by I-beams (15).

3. A method for constructing a shore composite platform, characterized in that: The following steps are involved: S10: According to the setting position of the upper cap on the bank, a protective pile (9) is constructed on the side of the cap facing the road, the surface soil of the bank slope is cleaned, and a backfill platform step is excavated; S20: Grooves are opened along the other three sides of the cap, the grooves are filled with sand, and cofferdam steel pipe piles (1) are inserted into the grooves to close with the protection piles (9) to form a cofferdam; S30: Grouting is performed inside the steel pipe pile (1) to the bottom of the cap, so that the soil in this area is consolidated to form a grouting consolidation wall (3); S40: installing a retaining wall formwork inside the steel pipe pile (1), tying steel bars, pouring concrete into the space between the retaining wall formwork and the steel pipe pile (1) to form a concrete retaining wall (2); after the strength of the concrete retaining wall (2) reaches the required level, backfilling crushed stone (4) in the area enclosed by the concrete retaining wall (2) and the protection pile (9) and compacting the crushed stone; S50: pouring a concrete cushion layer (5) on the top surface of the crushed stone (4) to form a backfill platform; constructing the steel trestle platform (6) on the left and right sides of the cap by the fishing method, and when the top elevation of the steel trestle platform (6) is consistent with the top elevation of the backfill platform, the backfill platform and the steel trestle platform (6) are overlapped to form an integral platform; S60: Construction of bored piles on a backfill platform; S70: Excavate the foundation pit on the backfill platform, and install the inner support of the cofferdam simultaneously with the excavation downwards of the foundation pit; After the foundation pit is excavated, the cofferdam bottom seal concrete (14) is poured underwater, and the water in the cofferdam is pumped out after the bottom seal concrete (14) reaches the designed strength; S80: After pumping is completed, firstly, the inside of the weir is cleaned and the steel casing (11) of the bored pile is cut off, and the pile head is chiseled off. Then, the cap steel bars are tied and the cap is cast. Finally, the support inside the cofferdam is removed, the tower base steel bars are tied, the formwork is installed, and the tower base concrete is cast.

4. The method for constructing a shore composite platform according to claim 3, characterized in that: The steel pipe pile (9) is provided with steel bars and is internally poured with concrete.

5. The method for constructing a shore composite platform according to claim 3, characterized in that: In step S40, the concrete retaining wall (2) is located above the grouting consolidation wall (3).

6. The method for constructing a shore composite platform according to claim 3, characterized in that: In step S50, the steel trestle platform (6) is erected forward by means of a crawler crane using the high bank side fishing method.

7. The method for constructing a shore composite platform according to claim 3, characterized in that: In step S50, when the top elevations of the steel trestle platform (6) and the backfill platform are consistent, the steel trestle platform (6) and the backfill platform are connected by overlapping I-beams (15), and a bridge deck is laid on top.

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