Integrated anchor bolt and steel column base structure with bolt head

Abstract

The utility model relates to an integrated anchor bolt and steel column base structure with a bolt head. The method is suitable for the field of constructional engineering. The technical problem to be solved by the utility model is to provide the integrated anchor bolt and steel column base structure with the bolt head. According to the technical scheme, the integrated anchor bolt with the bolt head is characterized by comprising a bolt rod, a first end of the bolt rod is an embedded end used for being anchored into a concrete structure, and a second end of the bolt rod is an embedded end used for being anchored into the concrete structure; the bolt head is arranged at the first end of the bolt rod and is coaxial with the bolt rod, the distance from the edge of the bolt head to the central axis of the bolt head is 1d-2d, d is the diameter of the bolt rod, and the height of the bolt head is half of the diameter d of the bolt rod and is not less than 20mm.

Description

Technical Field

[0001] The utility model relates to an integrated anchor bolt with a bolt head and a steel column foot structure, which is applicable to the field of construction engineering. Background Art

[0002] When the steel column foot is embedded in the foundation, anchor bolts need to be set. There are two types of anchor bolts: drilled anchor bolts and cast-in-place anchor bolts. Cast-in-place anchor bolts are more common in actual projects. The bearing capacity of cast-in-place anchor bolts comes from the bonding between the anchor bolt shaft and the concrete and the pressure of the hook or expanded end plate on the concrete.

[0003] Depending on the shape of the embedded end, anchor bolts are available in the form of J-shaped anchor bolts, screw anchor bolts, and anchor bolts with end plates. J-shaped anchor bolts rely on the anchoring force between the anchor bolt and the concrete to function, and a hook is usually set at the end (such as the hook length is 3.5 times the diameter) as a structural requirement. Anchor bolts with end plates are pressure-bearing anchor bolts that rely on the extrusion force between the end plate and the concrete to function, but an overly large end bearing plate will make its margin from the outer edge of the concrete foundation and the net spacing between the anchor bolts too small, causing the foundation concrete section to be weakened, and the end anchor plate is usually welded to the anchor bolt. For screw anchor bolts, a certain length of thread is required to ensure the sleeve connection of the end nut, and the thread production cost is relatively high.

[0004] In general, the column foot anchor bolts commonly used in engineering have the following problems: (1) J-shaped anchor bolts, the hook at the end is only a structural requirement, which increases the amount of steel and requires a larger embedding depth. (2) Screw anchor bolts, the end needs to be set with a certain length of thread, the thread manufacturing cost is high and there is a possibility of nut stripping. (3) Anchor bolts with end plates, the end plate needs to be welded, which not only increases the construction process but also causes the weakening of the foundation concrete section. Utility Model Content

[0005] The technical problem to be solved by the utility model is: in view of the above existing problems, an integrated anchor bolt with a bolt head and a steel column foot structure is provided.

[0006] The technical solution adopted by the utility model is: an integrated anchor bolt with a bolt head, characterized in that it comprises:

[0007] A bolt rod, the first end of which is an embedded end for anchoring into a concrete structure;

[0008] The bolt head is arranged at the first end of the bolt rod and is coaxial with the bolt rod. The distance from the edge of the bolt head to its central axis is 1d to 2d, d is the bolt rod diameter, and the height of the bolt head is half of the bolt rod diameter d and is not less than 20 mm.

[0009] The cross section of the bolt head is circular.

[0010] The diameter of the bolt head is 2d, 2.5d or 3d.

[0011] The cross section of the bolt head is square.

[0012] The side length of the bolt head is 2d, 2.5d or 3d.

[0013] The cross section of the bolt head is trapezoidal.

[0014] The side length of the bottom surface of the bolt head is 2d, 2.5d or 3d.

[0015] The bolt head and the bolt rod are made in one piece.

[0016] A steel column base structure, characterized in that it comprises a plurality of integrated anchor bolts with bolt heads, wherein the bolt head end of the anchor bolt is embedded in a concrete foundation, and the other end of the anchor bolt is connected to the steel column in cooperation with a nut and an anchor bolt gasket.

[0017] The gap between the steel column bottom plate of the steel column and the lower concrete foundation is filled with fine stone concrete.

[0018] An installation pit is provided on the concrete foundation corresponding to the installation position of the steel column, the lower end of the steel column is inserted into the installation pit, and the installation pit is backfilled with plain concrete.

[0019] The beneficial effects of the utility model are as follows: the utility model avoids the structural requirement of setting a hook at the end of the J-shaped anchor bolt by adding a bolt head to the anchoring end of the bolt rod, and can also avoid the increase in construction process caused by welding the end plate at the end of the anchor bolt with end plate and the weakening of the foundation concrete section caused by excessive anchor plate size.

[0020] The utility model increases the bonding failure area between the anchor bolt and the concrete and improves the anchoring force of the anchor bolt in the foundation by adding a bolt head at the embedded end of the anchor bolt.

[0021] The utility model can reduce the embedding depth of the anchor bolt when achieving the same anchoring strength by adding a bolt head to the anchoring end of the bolt rod.

[0022] The utility model can make the integrated anchor bolt with the bolt head as a standard part in the factory, which can ensure the overall stress and prevent the nut from slipping during bolt connection or the weld from being damaged during welding connection, thus facilitating the selection of the project. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the structure of the steel column base in the embodiment.

[0024] Figure 2 for Figure 1 AA section view.

[0025] Figure 3 1 is a structural diagram of an integrated anchor bolt with a bolt head in an embodiment.

[0026] Figure 4 Schematic diagram of anchor bolt anchoring force in the embodiment.

[0027] Figure 5 Schematic diagram of an integrated anchor bolt structure with different bolt head types in an embodiment.

[0028] Figure 6 This is a schematic diagram of the completion of the construction of the steel column base structure in the embodiment.

[0029] Figure 7 It is a construction step diagram of the steel column base structure in the embodiment.

[0030] 1. Steel column;

[0031] 11. Steel column wall plate; 12. Steel column bottom plate; 13. Anchor bolt holes; 14. Stiffening ribs; 15. Pads;

[0032] 2. Concrete foundation;

[0033] 3. Anchor bolt;

[0034] 31. bolt head; 32. bolt rod; 33. thread; 34. anchor bolt washer; 35. nut;

[0035] 4. Plain concrete;

[0036] 5. Fine stone concrete. DETAILED DESCRIPTION

[0037] Embodiment 1: This embodiment is an integrated anchor bolt with a bolt head, characterized in that it includes a bolt rod, the first end of the bolt rod is an embedded end for anchoring in a concrete structure, the bolt rod is threaded and threadedly connected to two upper and lower nuts, and each nut is provided with an anchor gasket.

[0038] In this example, a bolt head is connected to the first end (buried end) of the bolt rod. The bolt head is made integrally with the bolt rod. The distance from the edge of the bolt head to its central axis is 1d~2d, d is the diameter of the bolt rod, and the height of the bolt head is half of the bolt rod diameter d and not less than 20mm.

[0039] In this embodiment, the cross section of the bolt head is circular, square or trapezoidal. The diameter of the circular bolt head is preferably 2d, 2.5d or 3d; the side length of the square bolt head is preferably 2d, 2.5d or 3d; the bottom side length of the trapezoidal bolt head is 2d, 2.5d or 3d.

[0040] In this embodiment, the cross-section of the anchor bolt end is appropriately increased by the bolt head, thereby increasing the bonding failure area between the anchor bolt and the concrete, thereby improving the anchoring strength of the anchor bolt in the foundation. At the same time, the one-piece anchor bolt with a bolt head transfers the failure surface from the anchor bolt surface to the concrete, which can reduce the anchor bolt embedding depth.

[0041] Take the bolt head with twice the diameter of the anchor bolt as an example. The bottom diameter of the cross section of the ordinary anchor bolt is d, while the bottom diameter of the cross section of the integrated anchor bolt with a bolt head with twice the diameter is 2d. The bond failure surface between the anchor bolt and the concrete is the contact surface between the bottom of the anchor bolt and the concrete, which is represented by the bond failure area Scor. According to the bond failure area calculation formula, it can be seen that adding a bolt head with twice the diameter of the anchor bolt at the bottom can increase the bond failure area by 3 times.

[0042]

[0043] At the same time, the bolt head and anchor rod are prefabricated in the factory as an integral anchor bolt, which avoids welding workload and ensures its reliability.

[0044] This embodiment can play the same role as the anchor bolt with end plate widely used in current projects. The anchor bolt with end plate has been proven to effectively improve the pull-out strength of the anchor bolt by welding the end plate at the end of the anchor rod. According to existing research, the larger the end plate size, the greater the pull-out strength, but the larger the end bearing plate, the smaller the effective tensile section of the concrete at the height of the bottom surface of the end bearing plate, and the larger the end bearing plate, the smaller the margin from the concrete foundation or the outer edge of the column and the net spacing of the anchor bolts, causing the foundation concrete section to be seriously weakened.

[0045] The disadvantage of anchor bolts with end plates is that they need to be welded. First, the workload on site is increased and the quality cannot be guaranteed sometimes. Second, the size of the welded end plates is usually more than 3d. The cross section of the foundation concrete may be seriously weakened due to the small margin between the end plate and the outer edge of the concrete foundation or column and the net spacing between the anchor bolts.

[0046] In this embodiment, commonly used anchor bolts are made into an integrated standard part. Firstly, the workload of on-site welding is avoided. Secondly, the bolt head size is designed to be 2d, 2.5d or 3d of the bolt rod, which can avoid the end plate from being too close to the concrete foundation or the outer edge of the column and the net spacing between the anchor bolts being too small, causing the foundation concrete section to be seriously weakened.

[0047] Embodiment 2: This embodiment is a steel column base structure with a concrete foundation. An installation space corresponding to the steel column is reserved on the concrete foundation. A number of anchor bolts in Embodiment 1 are provided on the bottom surface. The bolt head end of the anchor bolt is buried in the concrete foundation, and the other end of the anchor bolt is clamped to the steel column base plate of the steel column through a nut and an anchor gasket.

[0048] In this example, the gap between the steel column bottom plate and the lower concrete foundation of the steel column is filled with fine stone concrete. The lower end of the steel column is inserted into the installation pit, and the installation pit is backfilled with plain concrete.

[0049] The specific construction method of the steel column base structure in this embodiment includes the following steps:

[0050] S1. Anchor bolts and matching hole plates are installed and positioned. Anchor bolts consist of bolt heads and bolt rods, and are used in conjunction with anchor bolt washers and nuts. Threads are set on the bolt rods.

[0051] S2. Pre-embed anchor bolts in the concrete foundation.

[0052] S3. Acceptance of anchor bolts.

[0053] S4. Installation and positioning of steel columns. The steel columns are composed of steel column wall panels (box-shaped columns are shown in the figure), with steel column bottom plates welded at the bottom and stiffening ribs welded on the side walls. Anchor holes for anchor bolts are preset on the steel column bottom plates. The anchor bolts are connected to the steel columns through anchor bolt washers, nuts and washers on the steel column components.

[0054] S5. Fine stone concrete is used for secondary pouring between the top surface of the concrete foundation and the bottom plate of the steel column.

[0055] S6. Fill the reserved installation space of the concrete foundation with plain concrete to the structural slab elevation.

[0056] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An integrated anchor bolt with a bolt head, characterized in that: include: A bolt rod, the first end of which is an embedded end for anchoring into a concrete structure; The bolt head is arranged at the first end of the bolt rod and is coaxial with the bolt rod. The distance from the edge of the bolt head to its central axis is 1d to 2d, d is the bolt rod diameter, and the height of the bolt head is half of the bolt rod diameter d and is not less than 20 mm.

2. The one-piece anchor bolt with a bolt head according to claim 1, characterized in that: The cross section of the bolt head is circular.

3. The one-piece anchor bolt with a bolt head according to claim 2, characterized in that: The diameter of the bolt head is 2d, 2.5d or 3d.

4. The one-piece anchor bolt with a bolt head according to claim 1, characterized in that: The cross section of the bolt head is square.

5. The one-piece anchor bolt with a bolt head according to claim 4, characterized in that: The side length of the bolt head is 2d, 2.5d or 3d.

6. The one-piece anchor bolt with a bolt head according to claim 1, characterized in that: The cross section of the bolt head is trapezoidal.

7. The one-piece anchor bolt with a bolt head according to claim 6, characterized in that: The side length of the bottom surface of the bolt head is 2d, 2.5d or 3d.

8. The one-piece anchor bolt with a bolt head according to claim 1, characterized in that: The bolt head and the bolt rod are made in one piece.

9. A steel column base structure, characterized in that: It comprises several one-piece anchor bolts with bolt heads as claimed in any one of claims 1 to 8, wherein the bolt head end of the anchor bolt is embedded in the concrete foundation, and the other end of the anchor bolt is connected to the steel column in cooperation with a nut and an anchor bolt gasket.

10. The steel column base structure according to claim 9, characterized in that: The gap between the steel column bottom plate of the steel column and the lower concrete foundation is filled with fine stone concrete.

11. The steel column base structure according to claim 9 or 10, characterized in that: An installation pit is provided on the concrete foundation corresponding to the installation position of the steel column, the lower end of the steel column is inserted into the installation pit, and the installation pit is backfilled with plain concrete.

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