CN205557551U - Configuration rebar's offshore wind turbines foundation grouting bushing structure - Google Patents

Abstract

The utility model relates to a foundation grout casing connection structure for an offshore wind power unit equipped with steel bars, comprising a vertical steel pipe pile and a steel casing, the steel pipe pile and the steel casing are nested coaxially with each other, and the steel pipe The pile and the steel casing form an annular cavity between the adjacent pipe walls at the nesting end, the annular cavity is bound with steel bars for annular force, and the annular cavity is filled with steel pipe piles and steel The casing is bonded as one grout. Compared with the traditional grouting connection, the utility model avoids or delays the occurrence and development of radial cracks in the grouting body under the horizontal load, prevents the grouting body from separating from the steel pipe pile and steel casing, and improves the bending bearing capacity of the connection, which is especially suitable for For the connection between the single pile foundation and the transition section.

Description

The foundation grouting casing connection structure of offshore wind turbines with steel bars

technical field

The utility model provides a foundation grouting bushing connection structure of an offshore wind turbine equipped with steel bars, which belongs to the field of foundation structures of the offshore wind turbine.

Background technique

The grouting casing connection belongs to the lap connection of two circular pipes with different diameters. It is to pour grouting materials such as cement slurry into the annular cavity formed between the pipe walls. Flattening creates a mechanical interlock to transmit axial pressure. The grout casing connection has the advantages of good integrity, convenient construction and low cost, and is firstly widely used in the structure of offshore oil production platforms. In recent years, grouted casing connections have gradually been applied in the foundation structure of offshore wind turbines. Comparing the foundation of the offshore oil production platform and the foundation of the offshore wind turbine, it can be found that: 1) The diameter and thickness of the pile foundation of the foundation of the offshore wind turbine are relatively large. According to the European statistical results before 2007, the maximum diameter-thickness ratio of steel pipe piles used in offshore wind power projects is 100; the diameter-thickness ratio of steel pipe piles used in offshore oil production platform foundations does not exceed 40. 2) The foundation grouting connection of offshore wind turbines The length is smaller. The grouting connection of offshore platforms requires that the connection length is not less than 6 times the diameter of the steel pipe pile; the length of the grouting connection for offshore wind power is mostly 1.5 to 2.5 times the diameter of the steel pipe pile. 3) Compared with the grouting connection of the offshore oil production platform, the stress of the foundation grouting connection of the offshore wind turbine is more complicated. In addition to bearing the vertical gravity load of the superstructure and equipment, the cyclic dynamic load of waves and the corrosion of seawater, the offshore wind power grouting connection also bears a large dynamic load of the wind turbine. Under the dynamic load of the fan, the grouting connection part mainly bears the bending moment.

Under the action of bending moment, the steel pipe pile and the casing transmit the bending moment through the lateral extrusion force at the grouting connection section. , which is often greater than the stress value generated by a simple vertical load. Previous tests have shown that if the vertical stress generated by the bending moment does not exceed the stress value generated by the vertical load, the reduction of the axial bearing capacity due to the presence of the bending moment does not exceed 18%. Under the action of the bending moment, the cross-section of the circularly distributed rods will become elliptical, resulting in different degrees of separation between the steel surface and the grouting body on both sides of the bending moment direction; at the same time, the lower section perpendicular to the bending moment direction is compressed One side produces radial displacement under the action of compressive stress, resulting in the disengagement of the structural surface from the grouting body in a local area of the upper part of the grouting body. The existing test and actual measurement results show that the disengagement distance can reach 6mm; The compression side perpendicular to the direction of the bending moment will generate a large bending stress, which will lead to the appearance of radial cracks. Cracks will lead to a reduction in the stiffness of the connection, further increase the elliptical deformation, reduce the flexural bearing capacity of the connection under static load and fatigue load, and indirectly reduce the compressive bearing capacity of the connection.

Utility model content

The purpose of the utility model is to provide a foundation grouting casing connection structure for offshore wind turbines equipped with steel bars for the above deficiencies.

The solution adopted by the utility model to solve the technical problem is a connection structure of offshore wind turbine foundation grouting sleeves with steel bars, including vertical steel pipe piles and steel sleeves, and the steel pipe piles and steel sleeves are coaxial with each other. Nesting, the steel pipe pile and the steel casing form a ring cavity between the adjacent pipe walls at the nesting end, the ring cavity is bound with steel bars for annular force, and the ring cavity is filled with useful It is a grouting body that bonds steel pipe piles and steel casings into one.

Further, the steel casing is coaxially sleeved on the outside of the steel pipe pile, and an annular cavity is formed between the outer wall of the steel pipe pile and the inner wall of the steel casing.

Further, the steel bars are symmetrically located in the upper middle part and the lower middle part of the ring cavity, and several stirrups are tied to the steel bars.

Further, the steel bars are located at the middle upper part of the 25% range and the middle lower part of the 25% range of the ring cavity.

Further, a grouting leak prevention device is provided at the grouting port of the annular cavity.

Further, the inner wall of the steel casing is provided with a temporary support.

Further, the material of the grouting body is high-strength cement mortar.

Compared with the prior art, the utility model has the following beneficial effects: compared with the traditional grouting connection, the utility model avoids or delays the occurrence and development of radial cracks in the grouting body under the horizontal load, and prevents the grouting body from being connected with the steel pipe pile, The steel casing is separated to improve the flexural bearing capacity and compressive bearing capacity of the connection, especially suitable for the connection between the single pile foundation and the transition section.

Description of drawings

Below in conjunction with accompanying drawing, the utility model patent is further described.

Fig. 1 is the structural representation of this utility model;

In the picture:

1-steel pipe pile; 2-steel casing; 3-ring cavity; 4-rebar; 5-grouting body; 6-stirrup; 7-grouting leakage prevention device; 8-temporary support

detailed description

Below in conjunction with accompanying drawing and specific embodiment the utility model is further described.

As shown in Figure 1, a foundation grout casing connection structure for offshore wind turbines with steel bars includes a vertical steel pipe pile 1 and a steel casing 2, the steel pipe pile and the steel casing are nested coaxially with each other, The steel pipe pile and the steel casing form an annular cavity 3 between the adjacent pipe walls at the nesting end, the annular cavity is bound with a steel bar 4 for annular force, and the annular cavity is filled with A grouting body 5 in which steel pipe piles and steel sleeves are bonded together.

In this embodiment, the steel casing is coaxially sleeved on the outside of the steel pipe pile, and an annular cavity is formed between the outer wall of the steel pipe pile and the inner wall of the steel casing.

In this embodiment, the steel bars are symmetrically located in the middle upper part and the middle lower part of the ring cavity, and several stirrups 6 are tied to the steel bars.

In this embodiment, the steel bars are located at the middle upper part of the 25% range and the middle lower part of the 25% range of the ring cavity.

In this embodiment, a grouting leak prevention device 7 is provided at the grouting port of the annular cavity.

In this embodiment, a temporary support 8 is provided on the inner wall of the steel casing.

In this embodiment, the material of the grouting body is high-strength cement mortar.

In this embodiment, the connection method of the foundation grouting sleeve connection structure of the offshore wind turbine with steel bars includes the following steps:

(1) First, the steel casing and the steel pipe pile are coaxially nested, and the steel bars are bound in the ring cavity between the steel pipe pile and the adjacent pipe wall of the steel casing, and the steel bars are respectively tied in the ring cavity The upper middle part of the 25% range and the lower middle part of the 25% range;

(2) After the steel bar binding is completed, pour high-strength cement mortar into the ring cavity to bond the steel pipe pile and the steel casing into one, and seal the grouting port with a grouting leak-proof device to complete the connection.

The above preferred embodiments have further described the purpose, technical solutions and advantages of the utility model in detail. It should be understood that the above descriptions are only preferred embodiments of the utility model and are not intended to limit the utility model. For new models, any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present utility model shall be included within the protection scope of the present utility model.

Claims (7)

1. An offshore wind turbine foundation grouting casing connection structure configured with steel bars, characterized in that: it includes vertical steel pipe piles and steel casings, and the steel pipe piles and steel casings are nested coaxially with each other. The steel pipe pile and the steel casing form a ring cavity between the adjacent pipe walls at the nesting end, the ring cavity is bound with steel bars for ring force, and the ring cavity is filled with steel pipe piles A grouting body bonded to a steel casing. 2. The offshore wind turbine foundation grouting sleeve connection structure configured with steel bars according to claim 1, characterized in that: the steel sleeve is coaxially sleeved on the outside of the steel pipe pile, and the outer wall of the steel pipe pile is in contact with the steel pipe pile. An annular cavity is formed between the inner walls of the steel casing. 3. The offshore wind turbine foundation grout casing connection structure with steel bars according to claim 1, characterized in that: the steel bars are symmetrically located in the upper middle part and the lower middle part of the ring cavity, and several hoops are bound on the steel bars ribs. 4. The offshore wind turbine foundation grout casing connection structure with steel bars according to claim 1, characterized in that: the steel bars are located at the middle upper part of the 25% range of the ring cavity and the middle lower part of the 25% range. 5 . The foundation grouting sleeve connection structure of offshore wind turbines with steel bars according to claim 1 , wherein a grouting leak-proof device is provided at the grouting port of the annular cavity. 6 . 6 . The offshore wind turbine foundation grout casing connection structure with steel bars according to claim 2 , characterized in that: the inner wall of the steel casing is provided with a temporary support. 7 . 7 . The foundation grouting casing connection structure of offshore wind turbines equipped with steel bars according to claim 1 , characterized in that: the material of the grouting body is high-strength cement mortar.