A secondary anchor shear-resistant concrete self-drilling anchor bolt

Abstract

The utility model discloses a secondary anchoring shear-resistant concrete self-drilling anchor bolt, which relates to the technical field of anchor bolts, including a threaded rod and an expansion mechanism, wherein the outer wall of the threaded rod is provided with a spiral assembly, the expansion mechanism includes an expansion sleeve, a pressure mechanism is provided between the expansion sleeve and the threaded rod, and a pressure mechanism is provided on the inner wall of the expansion sleeve, and the expansion sleeve expands by contacting the pressure mechanism with the pressure mechanism. The utility model utilizes the setting of the expansion sleeve, and then through the cooperation of the pressure mechanism and the pressure mechanism, the expansion sleeve is sleeved on the outer wall of the smooth rod, and then as the threaded rod moves into the concrete, the smooth rod will squeeze the convex point, so that as the smooth rod moves, the expansion sleeve is expanded at the opening of the convex point, and the expanded expansion sleeve directly squeezes the hole wall of the concrete at the position, thereby completing the secondary anchoring between the anchor bolt and the concrete, improving the pull-out bearing capacity of the anchor bolt and also improving the shear strength of the anchor bolt.

Description

Technical Field

[0001] The utility model relates to the technical field of anchor bolts, in particular to a secondary anchoring shear-resistant concrete self-drilling anchor bolt. Background Art

[0002] Concrete self-drilling anchors are easy and quick to install, and their anchoring margins and spacing are smaller than those of expansion anchors of the same specification. After anchoring, they can provide strong pull-out bearing capacity by relying on the mechanical interlocking of the threads and the threaded hole walls. They are widely used in tensile parts of construction projects. Application areas include connections at key parts of infrastructure, fixation of heavy machinery and equipment, and fastening and suspension of various equipment in house construction.

[0003] Existing concrete self-drilling anchor bolts are rarely used to bear only shear force. When used as shear connectors, the anchor bolts are easy to bend and produce plastic hinges, resulting in reduced node bearing capacity. Therefore, we designed a secondary anchor shear-resistant concrete self-drilling anchor bolt with high bearing capacity and reliable anchoring effect that can be used under shear force and combined tension-shear action. Utility Model Content

[0004] The utility model aims to provide a secondary anchoring shear-resistant concrete self-drilling anchor bolt to solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above purpose, the utility model provides the following technical solution: a secondary anchor shear-resistant concrete self-drilling anchor bolt, comprising:

[0006] A threaded rod, wherein the outer wall of the threaded rod is provided with a spiral component;

[0007] The expansion mechanism comprises an expansion sleeve, a pressure mechanism is arranged between the expansion sleeve and the threaded rod, a pressure mechanism is arranged on the inner wall of the expansion sleeve, and the expansion sleeve expands through the contact between the pressure mechanism and the pressure mechanism.

[0008] Preferably, the spiral assembly includes a screw thread, the screw thread is fixedly sleeved on the outer wall of the threaded rod, the screw thread is arranged in a spiral shape, and an easy-insertion mechanism is arranged at the bottom end of the threaded rod.

[0009] Preferably, the easy-insertion mechanism comprises a pointed end, which is arranged at the bottom end of the threaded rod, and the size of the pointed end gradually decreases from top to bottom.

[0010] Preferably, the pressure-applying mechanism comprises a smooth rod, the smooth rod is fixedly connected to the top end of the threaded rod, the smooth rod is inserted into the inner wall of the expansion sleeve, and a twisting mechanism is provided at the top end of the smooth rod.

[0011] Preferably, the pressure-bearing mechanism comprises a plurality of protrusions, the plurality of protrusions are respectively fixedly connected to the bottom of the inner wall of the expansion sleeve, the plurality of protrusions are arranged in a ring array, and the plurality of protrusions are arranged in a cone shape.

[0012] Preferably, the outer wall of the expansion sleeve is provided with a plurality of paving grooves, the plurality of paving grooves are arranged in a ring array, the paving grooves and the protrusions are arranged in a staggered manner, and the inner wall of the paving groove is provided with a connecting groove.

[0013] Preferably, the twisting mechanism includes a flange head, the top end of the smooth rod is fixedly connected with a connecting flat washer, the top end of the connecting flat washer is fixedly connected to the bottom end of the flange head, and the flange head is a regular hexagonal block.

[0014] Technical effects and advantages of the utility model:

[0015] The utility model utilizes the setting of the expansion sleeve, and then through the cooperation of the pressure-applying mechanism and the pressure-receiving mechanism, before the anchor bolt is screwed into the anchored object and the concrete, the expansion sleeve needs to be sleeved on the outer wall of the smooth rod, and then as the threaded rod moves into the concrete, the smooth rod will squeeze the convex point, so that as the smooth rod moves, the expansion sleeve is expanded at the opening of the convex point, and the expanded expansion sleeve position directly squeezes the hole wall of the concrete, thereby completing the second anchoring between the anchor bolt and the concrete, improving the pull-out bearing capacity of the anchor bolt and the shear strength of the anchor bolt at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a front sectional structural schematic diagram of the utility model.

[0017] Figure 2 It is a schematic diagram of the three-dimensional structure of the expansion sleeve of the utility model.

[0018] Figure 3 This is a structural schematic diagram of the working state of the anchor bolt of the utility model.

[0019] In the figure: 101, smooth rod; 102, threaded rod; 201, expansion sleeve; 202, convex point; 301, clearance groove; 302, connecting groove; 401, flange head; 402, connecting flat washer; 501, anchored object; 502, concrete. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0021] The utility model provides Figure 1-3 A secondary anchoring shear-resistant concrete self-drilling anchor bolt shown in the figure comprises a threaded rod 102 and an expansion mechanism. The outer wall of the threaded rod 102 is provided with a spiral assembly, which comprises a screw thread, which is fixedly sleeved on the outer wall of the threaded rod 102, and the screw thread is arranged in a spiral shape. The bottom end of the threaded rod 102 is provided with an easy-insertion mechanism, which comprises a pointed end, which is arranged at the bottom end of the threaded rod 102, and the size of the pointed end gradually decreases from top to bottom. The threaded rod 102 is screwed into the anchored object 501 and the concrete 502 in turn, and the anchored object 501 is anchored on the concrete 502 through the mechanical interlocking of the screw thread and the hole wall. At the same time, through the arrangement of the pointed end, it is more labor-saving to screw the threaded rod 102 into the anchored object 501 and the concrete 502. The smooth rod 101 is 1 mm larger than the nominal diameter of the threaded rod 102, which can partially improve the shear bearing capacity of the anchor bolt.

[0022] In a preferred embodiment, the expansion mechanism includes an expansion sleeve 201, a pressure mechanism is arranged between the expansion sleeve 201 and the threaded rod 102, a pressure mechanism is arranged on the inner wall of the expansion sleeve 201, and the expansion sleeve 201 expands by contacting the pressure mechanism with the pressure mechanism. The pressure mechanism includes a smooth rod 101, the smooth rod 101 is fixedly connected to the top of the threaded rod 102, the smooth rod 101 is inserted and arranged on the inner wall of the expansion sleeve 201, and a twisting mechanism is arranged on the top of the smooth rod 101. The pressure mechanism includes a plurality of protrusions 202, and the plurality of protrusions 202 are respectively fixedly connected to the bottom of the inner wall of the expansion sleeve 201, and the plurality of protrusions 202 are arranged in a ring array, and the plurality of protrusions 202 are arranged in a cone shape. When the anchor bolt is pushed to the anchored object 5 Before screwing the threaded rod 101 into the concrete 502, the expansion sleeve 201 needs to be sleeved on the outer wall of the smooth rod 101. Then, as the threaded rod 102 moves into the concrete 502, the smooth rod 101 will squeeze the protrusion 202. As the smooth rod 101 moves, the expansion sleeve 201 expands at the opening of the protrusion 202. The expanded expansion sleeve 201 directly squeezes the hole wall of the concrete 502, thereby completing the second anchoring between the anchor bolt and the concrete 502, improving the pull-out bearing capacity of the anchor bolt and the shear strength of the anchor bolt. The inner diameter and outer diameter of the expansion sleeve 201 are 1.5 mm and 2.5 mm larger than the nominal diameter of the threaded rod 102, respectively, and the maximum thickness of the protrusion 202 is 1 mm.

[0023] Among them, the outer wall of the expansion sleeve 201 is provided with a plurality of give way grooves 301, and the plurality of give way grooves 301 are arranged in a ring array, and the give way grooves 301 and the protrusions 202 are arranged in a staggered manner. The inner wall of the give way grooves 301 is provided with connecting grooves 302. Through the arrangement of the give way grooves 301 and the connecting grooves 302, after the protrusion 202 is squeezed, the expansion sleeve 201 located at the opening of the protrusion 202 can be easily expanded, thereby improving the stability and smoothness of the operation of the expansion mechanism.

[0024] Among them, the twisting mechanism includes a flange head 401, and the top end of the smooth rod 101 is fixedly connected with a connecting flat washer 402. The top end of the connecting flat washer 402 is fixedly connected to the bottom end of the flange head 401. The flange head 401 is a regular hexagonal block, which is convenient for twisting the anchor bolt. When the anchor bolt is completely screwed into the anchored object 501 and the concrete 502, the connecting flat washer 402 will directly contact the surface of the anchored object 501. Due to the large area setting of the connecting flat washer 402, the contact area with the anchored object 501 is increased, making the force more uniform and protecting the surface of the anchored object 501.

[0025] The specific operation steps when using the anchor bolt are as follows:

[0026] Step 1: Use an impact drill to drill a pre-drilled hole A with a diameter of 0.8 dd, which is the nominal diameter of the threaded rod 102, in the anchored object 501 and the concrete 502. The depth of the pre-drilled hole A is 10 mm greater than the total length of the smooth rod 101 and the threaded rod 102, and then clean the hole of the pre-drilled hole A;

[0027] Step 2: Use an impact drill to drill a pre-drilled hole B with a diameter DD equal to the outer diameter of the expansion sleeve 201 on the basis of the pre-drilled hole. The maximum allowable diameter of the pre-drilled hole B is 0.4 mm larger than the outer diameter of the expansion sleeve 201. The depth of the pre-drilled hole B is 5 mm larger than the length of the expansion sleeve 201. Then clean the hole of the pre-drilled hole B.

[0028] Step 3: Install the expansion sleeve 201 in the pre-drilled hole B, and use an electric drill to drive the anchor bolt into the concrete 502 along the pre-drilled hole A until the threaded rod 102 is completely driven in. The smooth rod 101 enters the expansion sleeve 201 and squeezes the protrusion 202 to expand the expansion sleeve 201, so that the anchor bolt is anchored to the anchored object 501 and the concrete 502 for a second time, and the installation is completed.

[0029] Through the test of the shear performance of the specimens with different fastener forms, it was found that the average shear limit bearing capacity of the STS-S group was 43.22KN, which was 40.92% and 24.05% higher than those of the HS group and the STS group respectively; the stiffness of the STS-S group was significantly higher than that of the other two groups, reaching 17.75kN / mm, followed by the HS group at 5.87kN / mm, and the STS group at the lowest at 2.97kN / mm. In summary, the combination of the anchor bolt and the expansion sleeve 201 of the present application can significantly improve the node's ability to resist deformation and shear bearing capacity, and the test data are shown below.

[0030]

[0031]

[0032] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A secondary anchor shear-resistant concrete self-drilling anchor bolt, characterized in that: include: A threaded rod (102), wherein the outer wall of the threaded rod (102) is provided with a spiral component; The expansion mechanism comprises an expansion sleeve (201), a pressure-applying mechanism is arranged between the expansion sleeve (201) and the threaded rod (102), a pressure-receiving mechanism is arranged on the inner wall of the expansion sleeve (201), and the expansion sleeve (201) expands through contact between the pressure-applying mechanism and the pressure-receiving mechanism.

2. The secondary anchor shear-resistant concrete self-drilling anchor bolt according to claim 1, characterized in that: The spiral assembly comprises a screw thread, the screw thread is fixedly sleeved on the outer wall of the threaded rod (102), the screw thread is arranged in a spiral shape, and an easy-insertion mechanism is arranged at the bottom end of the threaded rod (102).

3. The secondary anchor shear-resistant concrete self-drilling anchor bolt according to claim 2, characterized in that: The easy-insertion mechanism comprises a pointed end, which is arranged at the bottom end of the threaded rod (102), and the size of the pointed end gradually decreases from top to bottom.

4. The secondary anchor shear-resistant concrete self-drilling anchor bolt according to claim 1, characterized in that: The pressure mechanism comprises a smooth rod (101), the smooth rod (101) is fixedly connected to the top end of the threaded rod (102), the smooth rod (101) is inserted into the inner wall of the expansion sleeve (201), and a twisting mechanism is arranged at the top end of the smooth rod (101).

5. The secondary anchor shear-resistant concrete self-drilling anchor bolt according to claim 1, characterized in that: The pressure-bearing mechanism comprises a plurality of protrusions (202), the plurality of protrusions (202) are respectively fixedly connected to the bottom of the inner wall of the expansion sleeve (201), the plurality of protrusions (202) are arranged in a ring array, and the plurality of protrusions (202) are arranged in a cone shape.

6. The secondary anchor shear-resistant concrete self-drilling anchor bolt according to claim 5, characterized in that: The outer wall of the expansion sleeve (201) is provided with a plurality of clearance grooves (301), the plurality of clearance grooves (301) are arranged in a ring array, the clearance grooves (301) and the protrusions (202) are arranged in a staggered manner, and the inner wall of the clearance groove (301) is provided with a connecting groove (302).

7. The secondary anchor shear-resistant concrete self-drilling anchor bolt according to claim 4, characterized in that: The twisting mechanism comprises a flange head (401), the top end of the smooth rod (101) is fixedly connected with a connecting flat washer (402), the top end of the connecting flat washer (402) is fixedly connected to the bottom end of the flange head (401), and the flange head (401) is a regular hexagonal block.

Images