UHPC box type concrete filled steel tube composite column structure

Abstract

The invention discloses a UHPC box type concrete filled steel tube composite column structure, and relates to the technical field of concrete columns, the UHPC box type concrete filled steel tube composite column structure comprises a first UHPC template and a second UHPC template, a base is arranged in the second UHPC template, a tamping and vibrating mechanism is arranged above the base, the tamping and vibrating mechanism comprises a driving motor arranged above the base, the output end of the driving motor is provided with a transmission rod, and the transmission rod is connected with the first UHPC template and the second UHPC template. The side, away from the driving motor, of the transmission rod is fixedly connected with a first gear, the side edge of the first gear is in meshed connection with a short rack plate, the side, away from the first gear, of the short rack plate is fixedly connected with a first impact block, and when the driving motor runs, the first impact block is converted into a moving state from a static state; by means of the structure, efficient vibration tamping is achieved in the concrete casting process, through the tamping mode, the porosity of the interior of concrete can be remarkably reduced, the compactness of the concrete is improved, the problems of large shrinkage and cracks caused by the characteristics of UHPC materials can be effectively solved, stability and durability are high, and the structure is convenient to disassemble.

Description

Technical Field

[0001] The invention relates to the technical field of concrete columns, and in particular to a UHPC box-type steel tube concrete composite column structure. Background Art

[0002] UHPC, the full name of which is Ultra-High Performance Concrete, is a new type of cement-based composite material with extremely high strength, extremely low porosity and excellent durability. It uses a low water-cement ratio, does not contain coarse aggregate, and is mixed with a large amount of active mineral admixtures and steel fiber and other additives. By optimizing the particle grading and microstructure, the concrete has extremely high strength and toughness after hardening. The UHPC box-type steel tube concrete composite column structure is an innovative structural form that combines the advantages of ultra-high performance concrete (UHPC) and steel tube concrete. Steel tube concrete is a composite structural material formed by filling concrete into a steel tube. This structural form makes full use of the restraining effect of the steel tube on the concrete, so that the concrete is in a three-dimensional compression state, thereby improving the compressive strength and ductility of the concrete. At the same time, the steel tube can also be used as a construction template to simplify the construction process and improve construction efficiency. The UHPC box-type steel tube concrete composite column structure has a wide range of application prospects in bridge engineering, high-rise buildings, marine engineering and other fields due to its excellent mechanical properties and construction convenience. Especially in projects that need to withstand large spans, high loads and harsh environmental conditions, this structural form can better play its unique advantages.

[0003] After searching, the invention patent with Chinese patent number CN110042747A discloses a UHPC box-type steel tube concrete composite column structure, in which four column limbs are divided into two groups, and the two groups of column limbs are arranged symmetrically. The two column limbs of each group are connected by a tube-attached UHPC plate, and the two column limbs on the same side of the two groups of column limbs are connected by a reinforced UHPC plate. The column limb is composed of a steel tube concrete column and an outer UHPC layer. The reinforced UHPC plate includes a reinforced UHPC plate, and the reinforced UHPC plate is provided with Steel mesh, rectangular block A, both ends of the steel mesh are connected to the rectangular block A, the steel UHPC plate includes a tube-attached UHPC plate, the tube-attached UHPC plate is provided with a tube-attached, UHPC, rectangular block B, the tubes are arranged at equal intervals along the axial direction of the column limb, both ends of the tubes are connected to the rectangular block B, the rectangular block A and the rectangular block B are connected to the steel pipe. The composite column structure has good ductility, high bearing capacity, high rigidity, good integrity, light weight, good durability, excellent wear resistance and explosion resistance, and can reduce the space occupied by the pier column.

[0004] However, in actual use, the above-mentioned device has a larger shrinkage than ordinary concrete due to its low water-binder ratio, lack of coarse aggregate, and the addition of active mineral admixtures. Its internal porosity is high during the casting process, which may cause cracks in the structure during use, resulting in reduced working efficiency of the device. Therefore, a UHPC box-type steel tube concrete composite column structure is proposed. Summary of the invention

[0005] The purpose of the present invention is to solve the shortcomings of the prior art, that is, due to its low water-binder ratio, lack of coarse aggregate, and the addition of active mineral admixtures, the shrinkage is greater than that of ordinary concrete, and its internal porosity is high during the casting process, which may cause cracks in the structure during use, resulting in reduced working efficiency of the device, and a UHPC box-type steel tube concrete composite column structure is proposed.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A UHPC box-type steel tube concrete composite column structure, comprising a first UHPC template and a second UHPC template, wherein a base is arranged inside the second UHPC template, a tamping mechanism is arranged above the base, the tamping mechanism comprises a driving motor arranged above the base, a transmission rod is arranged at the output end of the driving motor, a first gear is fixedly connected to the side of the transmission rod away from the driving motor, a short rack plate is meshedly connected to the side of the first gear, a first impact block is fixedly connected to the side of the short rack plate away from the first gear, and when the driving motor is running, the first impact block is changed from a static state to a moving state;

[0008] An inner cavity plate is provided on one side of the second UHPC template close to the base, a vibrator is fixedly connected to the inner cavity plate on one side away from the second UHPC template, a spring is fixedly connected to the vibrator on one side away from the inner cavity plate, and a first vibration plate is fixedly connected to the spring on one side away from the vibrator;

[0009] Among them, cement and mineral admixtures: by adding silica fume and ground slag powder, the density and durability of UHPC can be improved, while reducing the amount of cement and reducing shrinkage; fine aggregate: selecting fine aggregate with smaller particle size can improve the fluidity of UHPC and reduce porosity; steel fiber: the addition of steel fiber can significantly improve the tensile strength and toughness of UHPC and reduce the occurrence of cracks; high-efficiency water reducer: high-efficiency water reducer can significantly reduce the water-cement ratio and improve the fluidity and density of UHPC; micro-expansion agent: adding a proper amount of micro-expansion agent can compensate for the shrinkage of UHPC and reduce the occurrence of cracks;

[0010] Reference ratio (per cubic meter of UHPC material), cement: about 450kg / m 3, silica fume: about 100kg / m3, ground slag powder: about 150kg / m 3 , fine aggregate: about 600kg / m 3 , Steel fiber: about 20kg / m 3 , high efficiency water reducing agent: about 3kg / m 3 , Micro expansion agent: about 20kg / m 3 , water: about 180kg / m 3 Through the above-mentioned ratio scheme, a UHPC material with low shrinkage, high strength, good fluidity and strong durability can be achieved.

[0011] The above technical solution further includes:

[0012] The base is fixedly connected to the driving motor, the top of the transmission rod is fixedly connected to a second gear, and the side of the second gear is transmission-connected to a second impact block.

[0013] A fixing column is fixedly connected above the base, and two groups of the fixing columns are obliquely symmetrically arranged.

[0014] A support plate is fixedly connected to one side of the fixing column away from the base. The support plate is rotationally connected to the first gear, and the support plate is slidingly connected to the short rack plate.

[0015] A steel pipe is provided on one side of the first UHPC template close to the inner cavity plate.

[0016] A fiber mesh is arranged on the side of the steel pipe, and the fiber mesh is arranged between the second UHPC template and the inner cavity plate.

[0017] A fixing mechanism is disposed outside the first UHPC template, and the fixing mechanism includes a first bearing member disposed outside the first UHPC template.

[0018] A pull block is rotatably connected to the side of the first bearing component, and a locking ring is rotatably connected inside the pull block.

[0019] A second bearing member is fixedly connected to a side edge of the second UHPC template, and a slot block is fixedly connected to a side of the second bearing member away from the second UHPC template.

[0020] A second vibration plate is arranged outside a side of the inner cavity plate close to the first UHPC template.

[0021] The present invention has the following beneficial effects:

[0022] 1. In the present invention, efficient vibration compaction is achieved during the concrete casting process through the built-in tamping mechanism and vibration transmission system, including the first vibration plate, the second vibration plate, the vibration transmitter, the spring, etc. This tamping method can not only significantly reduce the porosity inside the concrete and improve the density of the concrete, but also effectively avoid the large shrinkage and cracking problems caused by the characteristics of UHPC materials (low water-cement ratio, no coarse aggregate, and the addition of active mineral admixtures). The fiber mesh added on the side significantly enhances the crack resistance of the structure. The fiber mesh can effectively prevent the expansion of cracks when the concrete is subjected to tensile stress, thereby improving the stability and durability of the overall structure.

[0023] 2. In the present invention, by arranging a fixing mechanism outside the first UHPC formwork, including a first bearing member, a lever block, a locking ring, etc., and a second bearing member and a slot block on the side of the second UHPC formwork, the formwork can be quickly locked and unlocked. When the concrete solidifies, the staff only needs to simply pull the lever block to make the locking ring disengage from the slot block to easily separate the two formworks, which greatly improves the construction efficiency, facilitates the recycling and reuse of the formwork, reduces the construction time, and reduces the risk of formwork damage, which helps to reduce the overall construction cost and improve the economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a structural schematic diagram of a UHPC box-type steel tube concrete composite column structure proposed by the present invention;

[0025] Figure 2 It is a schematic diagram of the external structure of the present invention;

[0026] Figure 3 It is a schematic diagram of the first three-dimensional structure of the present invention;

[0027] Figure 4 It is a schematic diagram of a second three-dimensional structure in the present invention;

[0028] Figure 5 for Figure 2 A schematic diagram of the structure enlargement in the middle;

[0029] Figure 6 for Figure 3 Enlarged schematic diagram of the structure at point B in the middle.

[0030] In the figure: 1. first UHPC template; 2. second UHPC template; 3. base; 4. driving motor; 5. transmission rod; 6. first gear; 7. short rack plate; 8. first impact block; 9. second gear; 10. second impact block; 11. fixing column; 12. support plate; 13. vibration transmitter; 14. spring; 15. first vibration plate; 16. inner cavity plate; 17. steel pipe; 18. fiber mesh; 19. first bearing member; 20. lever block; 21. locking ring; 22. slot block; 23. second bearing member; 24. second vibration plate. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the 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.

[0032] Embodiment 1

[0033] like Figure 1-Figure 6 As shown, a UHPC box-type steel tube concrete composite column structure proposed by the present invention includes a first UHPC template 1 and a second UHPC template 2, a base 3 is arranged inside the second UHPC template 2, a tamping mechanism is arranged above the base 3, and the tamping mechanism includes a driving motor 4 arranged above the base 3, a transmission rod 5 is arranged at the output end of the driving motor 4, a first gear 6 is fixedly connected to the side of the transmission rod 5 away from the driving motor 4, a short rack plate 7 is meshed and connected to the side of the first gear 6, and a first impact block 8 is fixedly connected to the side of the short rack plate 7 away from the first gear 6, and when the driving motor 4 is running, the first impact block 8 is changed from a static state to a moving state;

[0034] An inner cavity plate 16 is provided on one side of the second UHPC template 2 near the base 3, a vibrator 13 is fixedly connected to the inner cavity plate 16 away from the second UHPC template 2, a spring 14 is fixedly connected to the vibrator 13 away from the inner cavity plate 16, and a first vibration plate 15 is fixedly connected to the spring 14 away from the vibrator 13;

[0035] The base 3 is fixedly connected to the driving motor 4, the top of the transmission rod 5 is fixedly connected to the second gear 9, and the side of the second gear 9 is transmission-connected to the second impact block 10;

[0036] A fixing column 11 is fixedly connected to the top of the base 3, and two groups of the fixing columns 11 are arranged obliquely symmetrically;

[0037] A support plate 12 is fixedly connected to one side of the fixed column 11 away from the base 3. The support plate 12 is rotatably connected to the first gear 6, and the support plate 12 is slidably connected to the short rack plate 7.

[0038] A steel pipe 17 is provided on one side of the first UHPC template 1 close to the inner cavity plate 16;

[0039] A fiber mesh 18 is disposed on the side of the steel pipe 17, and the fiber mesh 18 is disposed between the second UHPC template 2 and the inner cavity plate 16;

[0040] A second vibration plate 24 is disposed outside the inner cavity plate 16 on one side close to the first UHPC template 1 .

[0041] In this embodiment, two groups of the first UHPC template 1 and the second UHPC template 2 are provided, and a box-type mold group is formed with the inner cavity plate 16. The mixed UHPC material is cast inside the mold space formed between the first UHPC template 1, the second UHPC template 2 and the inner cavity plate 16. Four groups of steel pipes 17 are provided inside the mold space, and fiber meshes 18 are provided on the sides of the steel pipes 17. The sides of each group of steel pipes 17 are connected by fiber meshes 18. The addition of fiber meshes 18 can significantly improve the crack resistance of UHPC. When concrete is subjected to tensile stress, the fiber mesh can prevent the expansion of cracks, thereby improving the overall crack resistance of the structure. A fixed column 11 is fixedly connected above the base 3, and two groups of fixed columns 11 are symmetrically provided. The two groups of fixed columns 11 fix the support plate 12, so that the tamping mechanism can operate stably;

[0042] The tamping mechanism arranged above the start base 3 is started, and the driving motor 4 in the tamping mechanism starts to run. When the driving motor 4 runs, it starts to control the transmission rod 5 arranged at its output end to rotate. A first gear 6 is fixedly connected to the side of the transmission rod 5 away from the driving motor 4. When the transmission rod 5 rotates, it drives the first gear 6 to start rotating. When the first gear 6 rotates, it drives the short rack plate 7 meshing with the side thereof to start moving. Two groups of short rack plates 7 are arranged. When the two groups of short rack plates 7 move, they drive the first impact blocks 8 fixedly connected to the outside thereof to start moving, so that the two groups of first impact blocks 8 gradually start to move toward the direction of the second vibration plate 24. A second gear 9 is fixedly connected to the top of the transmission rod 5. When the transmission rod 5 rotates, it drives the second gear 9 to start rotating, so that the rotation of the second gear 9 can drive the second impact block 10 arranged on its side to start moving, and the two groups of second impact blocks 10 respectively move toward the outside of the two groups of first vibration plates 15. , so that the first vibration plate 15 begins to be pushed. When the first vibration plate 15 moves, the spring 14 fixedly connected to the outside thereof is compressed. The spring 14 is fixedly connected to the inner cavity plate 16 through the vibration transmitter 13 fixedly connected to the outside thereof, so that the spring 14 is compressed and accumulates elastic force under pressure. The second vibration plate 24 is subjected to the same pressure by the two groups of first impact blocks 8. When the elastic force accumulates to a certain extent, the drive motor 4 runs in the reverse direction, so that the two groups of first impact blocks 8 and the two groups of second impact blocks 10 are instantly moved away, releasing the elastic force of multiple groups of springs 14, so that the two groups of first vibration plates 15 and the two groups of second vibration plates 24 begin to vibrate under the influence of the elastic force of the springs 14. The first vibration plate 15 and the second vibration plate 24 transmit the vibration force to the inner cavity plate 16 through the vibration transmitter 13, so that the inner cavity plate 16 begins to vibrate, and the UHPC material inside the mold space and the concrete poured inside the steel pipe 17 are affected by the vibration, thereby reducing their internal porosity.

[0043] Embodiment 2

[0044] like Figure 1-Figure 6 As shown, based on the first embodiment, a fixing mechanism is arranged outside the first UHPC template 1, and the fixing mechanism includes a first bearing member 19 arranged outside the first UHPC template 1;

[0045] The first bearing member 19 is rotatably connected to a pull block 20 at the side, and a lock ring 21 is rotatably connected to the pull block 20;

[0046] A second bearing member 23 is fixedly connected to a side edge of the second UHPC template 2 , and a slot block 22 is fixedly connected to a side of the second bearing member 23 away from the second UHPC template 2 .

[0047] In this embodiment, after the UHPC material and concrete solidify, a first bearing member 19 is fixedly connected to the outside of the first UHPC formwork 1, and a lever block 20 is installed on the side of the first bearing member 19. The staff can pull the lever block 20 to make the lever block 20 start to rotate. When the lever block 20 rotates, it will drive the locking ring 21 set on the other side thereof to start moving. A second bearing member 23 is fixedly connected to the side of the second UHPC formwork 2, and a slot block 22 is fixedly connected to the side of the second bearing member 23. Before the locking ring 21 moves, it is fixed inside the slot block 22. At this time, the locking ring 21 moves and begins to gradually disengage from the fixed connection with the slot block 22, so that the first UHPC formwork 1 and the second UHPC formwork 2 are separated, and the staff can quickly disassemble the mold.

[0048] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A UHPC box-type steel tube concrete composite column structure, comprising a first UHPC formwork (1) and a second UHPC formwork (2), characterized in that: A base (3) is provided inside the second UHPC template (2), a tamping mechanism is provided above the base (3), the tamping mechanism comprises a driving motor (4) provided above the base (3), a transmission rod (5) is provided at the output end of the driving motor (4), a first gear (6) is fixedly connected to the side of the transmission rod (5) away from the driving motor (4), a short rack plate (7) is meshedly connected to the side of the first gear (6), a first impact block (8) is fixedly connected to the side of the short rack plate (7) away from the first gear (6), and when the driving motor (4) is in operation, the first impact block (8) is changed from a stationary state to a moving state; An inner cavity plate (16) is provided on a side of the second UHPC template (2) close to the base (3); a side of the inner cavity plate (16) away from the second UHPC template (2) is fixedly connected to a vibrator (13); a side of the vibrator (13) away from the inner cavity plate (16) is fixedly connected to a spring (14); and a side of the spring (14) away from the vibrator (13) is fixedly connected to a first vibration plate (15).

2. A UHPC box-type steel tube concrete composite column structure according to claim 1, characterized in that: The base (3) is fixedly connected to the driving motor (4); the top of the transmission rod (5) is fixedly connected to a second gear (9); and the side of the second gear (9) is transmission-connected to a second impact block (10).

3. The UHPC box-type steel tube concrete composite column structure according to claim 1, characterized in that: A fixing column (11) is fixedly connected to the top of the base (3), and two groups of the fixing columns (11) are arranged obliquely symmetrically.

4. A UHPC box-type steel tube concrete composite column structure according to claim 3, characterized in that: A support plate (12) is fixedly connected to the side of the fixed column (11) away from the base (3); the support plate (12) is rotationally connected to the first gear (6); and the support plate (12) is slidingly connected to the short rack plate (7).

5. The UHPC box-type steel tube concrete composite column structure according to claim 1, characterized in that: A steel pipe (17) is provided on one side of the first UHPC template (1) close to the inner cavity plate (16).

6. A UHPC box-type steel tube concrete composite column structure according to claim 5, characterized in that: A fiber mesh (18) is arranged on the side of the steel pipe (17), and the fiber mesh (18) is arranged between the second UHPC template (2) and the inner cavity plate (16).

7. The UHPC box-type steel tube concrete composite column structure according to claim 1, characterized in that: A fixing mechanism is arranged outside the first UHPC template (1), and the fixing mechanism comprises a first bearing member (19) arranged outside the first UHPC template (1).

8. The UHPC box-type steel tube concrete composite column structure according to claim 7, characterized in that: The first bearing member (19) is rotatably connected to a pull block (20) at its side, and a locking ring (21) is rotatably connected inside the pull block (20).

9. The UHPC box-type steel tube concrete composite column structure according to claim 7, characterized in that: A second bearing member (23) is fixedly connected to a side edge of the second UHPC template (2), and a slot block (22) is fixedly connected to a side of the second bearing member (23) away from the second UHPC template (2).

10. The UHPC box-type steel tube concrete composite column structure according to claim 1, characterized in that: A second vibration plate (24) is arranged outside a side of the inner cavity plate (16) close to the first UHPC template (1).

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