Cracked concrete structure for anti-seismic test

Abstract

The utility model discloses a cracked concrete structure for an anti-seismic test, which comprises a concrete layer and a plurality of pre-buried longitudinal steel bars, isolation sleeves are pre-buried at the junctions of the longitudinal steel bars and a pre-slotting plane, the longitudinal steel bars penetrate through the isolation sleeves, and the two ends of the longitudinal steel bars penetrate out of the concrete layer; a guide wood plate is further embedded in the concrete layer and located on the lower half portion of the pre-slotting plane. The isolation sleeve is arranged at the junction of the pre-embedded longitudinal bar and the pre-slotting plane in advance to isolate the concrete from the reinforcing steel bar and avoid direct contact between the concrete and the reinforcing steel bar, so that a crack can be expanded along the position more easily during slotting; and meanwhile, the wood plate is pre-embedded in the lower half part of the plane needing to be slotted, the connecting strength between the wood plate and the concrete is low, cracks are more easily generated from the position during slotting, and the guiding effect is achieved.

Description

Technical Field

[0001] This utility model relates to the field of post-anchoring technology, and in particular to a cracked concrete structure used in seismic testing. Background Technology

[0002] Post-anchoring technology refers to a connection technique that involves drilling holes in a hardened concrete substrate, embedding anchor bolts or reinforcing bars in the holes, and using mechanical locking forces or chemical bonding forces to effectively connect the new component to the substrate and transfer the load. With the large-scale construction of new buildings and the renovation of existing buildings, structural reinforcement projects are increasing year by year, and post-anchoring technology for concrete structures, a commonly used technique in engineering reinforcement, is being used more extensively.

[0003] When carrying out construction work, seismic fortification must be considered. As an important structural component, anchor bolts must be tested for seismic performance. In order to conduct seismic performance testing of anchor bolts, in addition to relevant seismic testing equipment, cracked concrete substrate is also an essential element.

[0004] Currently, there are several methods for creating cracked concrete. The first method involves placing two smooth concrete blocks together and applying external force to compress them, simulating the appearance of cracks. The second method involves manually striking a wedge to create cracks along the wedge. However, both methods have drawbacks. In actual working conditions, if cracks appear in concrete, the concrete can withstand the forces between the concrete blocks and the bonding force between the reinforced concrete, preventing complete cracking. The first method, however, relies on externally provided compressive force, which deviates significantly from real-world conditions and fails to accurately simulate the situation. The second method, manually striking a wedge to create cracks, is uncontrollable and only suitable for ordinary cracking tests. Further manpower is required for transporting and securing the concrete during seismic testing using anti-seismic equipment. Utility Model Content

[0005] To address the aforementioned problems, this invention provides a cracked concrete structure for seismic testing.

[0006] Therefore, the technical solution of this utility model is: a cracked concrete structure for seismic testing, comprising a concrete layer and a number of pre-embedded longitudinal steel bars, wherein an isolation sleeve is pre-embedded at the junction of the longitudinal steel bars and the pre-opening plane, the longitudinal steel bars pass through the isolation sleeve, and both ends of the longitudinal steel bars protrude out of the concrete layer; a guide board is also pre-embedded in the concrete layer, and the guide board is located in the lower half of the pre-opening plane.

[0007] Based on the above scheme and as a preferred embodiment of the above scheme: the orientation of the guide wooden board is the same as the orientation of the pre-opened plane, and it is perpendicular to the longitudinal steel bar.

[0008] Based on the above scheme and as a preferred embodiment of the above scheme: the concrete layer is provided with planned pre-opening joint positions, the pre-opening joint positions extend into the concrete layer to form a pre-opening joint plane, and the longitudinal reinforcing bars are separated from the pre-opening joint plane by isolation sleeves.

[0009] Based on the above scheme and as a preferred embodiment of the above scheme: the diameter of the longitudinal steel bar is 40mm.

[0010] Based on the above scheme and as a preferred embodiment of the above scheme: the longitudinal reinforcement is connected to the seismic testing equipment through a fixing plate and a fixing head; the fixing plate is provided with a number of reserved holes for the longitudinal reinforcement to pass through.

[0011] Based on the above scheme and as a preferred embodiment of the above scheme: the fixing head includes a steel bar nut, a ball joint, a steel plate and a rubber pad, and the longitudinal steel bar passes through the rubber pad, the steel plate and the ball joint in sequence, and then locks with the steel bar nut.

[0012] Compared with the prior art, the beneficial effects of this utility model are:

[0013] 1. Pre-install an isolation sleeve at the intersection of the pre-embedded longitudinal reinforcement and the pre-opened joint plane to separate the concrete from the reinforcement and prevent them from direct contact. This makes it easier for cracks to spread along this position when the joint is opened. At the same time, pre-embed a wooden board in the lower half of the plane where the joint needs to be opened. The bond strength between the wooden board and the concrete is low, and cracks are more likely to form at this position when the joint is opened, thus playing a guiding role.

[0014] 2. The device is equipped with a fixing plate and a fixing head, which can be connected to seismic testing equipment during testing. The fixing plate has pre-drilled holes to accommodate different types of cracked concrete and offers some expandability, allowing for testing with non-standard cracked concrete in the future. The fixing head is equipped with rubber pads to absorb shock and prevent damage to the device, while the ball joint ensures a tighter fixation of the concrete. Attached Figure Description

[0015] Figure 1 This is a structural schematic diagram of the first dimension of this utility model;

[0016] Figure 2 This is a schematic diagram of the structure of the second dimension of this utility model;

[0017] Figure 3 This is a schematic diagram of the structure of the fixing plate of this utility model;

[0018] Figure 4 This is a schematic diagram of the structure of the fixing head of this utility model.

[0019] The markings in the diagram are: 1. Concrete layer; 2. Longitudinal reinforcement; 3. Pre-opening position; 4. Isolation sleeve; 5. Guide board; 6. Fixing plate; 61. Reserved hole; 71. Rubber pad; 72. Steel plate; 73. Ball joint; 74. Rebar nut. Detailed Implementation

[0020] In the description of this utility model, it should be noted that the directional terms such as "center", "horizontal (X)", "longitudinal (Y)", "vertical (Z)", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", and "counterclockwise" indicate the orientation and positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. They should not be construed as limiting the specific protection scope of this utility model.

[0021] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features. Thus, the use of "first" and "second" to define a feature may explicitly or implicitly include one or more of that feature. In the description of this utility model, "several" or "a number" means two or more, unless otherwise explicitly specified.

[0022] See the attached diagram. The cracked concrete structure used for seismic testing in this embodiment includes a concrete layer 1 and several pre-embedded longitudinal reinforcing bars 2, with both ends of the longitudinal reinforcing bars 2 protruding from the concrete layer 1. The design fully considers anchor bolt installation requirements, and two sizes are designed based on the parameters of most commercially available anchor bolts, covering the application range of most commonly used anchor bolts. Simultaneously, cracked concrete also has regulations regarding reinforcement ratios, and the reinforcement arrangement is designed separately for the two different concrete layer sizes.

[0023] like Figure 1 As shown, the first type of concrete layer has dimensions of 1600*1200*450mm, with two rows of reinforcing bars distributed on it, each row containing four reinforcing bars with a diameter of 40mm. Figure 2 As shown, the second type of concrete layer measures 1600*1000*300mm, with two rows of reinforcing bars distributed on it. Each row has three reinforcing bars, with a center-to-center distance of 400mm between adjacent bars in each row. The diameter of the reinforcing bars is 40mm. These two types of concrete layers can cover conventional anchor bolts from M8 to M24, eliminating the need to design multiple types of concrete for different anchor bolts. This increases the versatility of the concrete and avoids the manpower and material resources wasted on preparing multiple molds.

[0024] The concrete layer 1 has a planned pre-opening position 3, which extends into the concrete layer 1 to form a pre-opening plane; an isolation sleeve 4 is pre-embedded at the junction of the longitudinal steel bar 2 and the pre-opening plane, and the longitudinal steel bar 2 passes through the isolation sleeve 4. The isolation sleeve 4 separates the concrete from the steel bar to avoid direct contact, so that when the opening is made, the crack will be more likely to extend along this position.

[0025] A guide board 5 is also pre-embedded in the concrete layer 1. The guide board 5 is located in the lower half of the pre-slit plane, and its orientation is the same as that of the pre-slit plane and perpendicular to the longitudinal reinforcement 2. After the concrete is poured, the board will remain in the concrete. The bond strength between the board and the concrete is relatively low, and cracks are more likely to form at this location when the slit is opened, thus playing a guiding role.

[0026] This embodiment is equipped with a fixing plate 6 and a fixing head, which can be connected to seismic testing equipment during testing. The fixing plate 6 is a steel plate installed on both sides of the concrete. Pre-drilled holes 61 are designed according to the concrete size to allow exposed reinforcing bars to pass through for concrete fixation. The pre-drilled holes 61 on the fixing plate 6 are fully compatible with the cracked concrete layers of the two designs described above and have a certain degree of scalability, allowing for testing with non-standard cracked concrete in the future.

[0027] The fixing head is a combination of a rubber pad 71, a steel plate 72, a ball joint 73, and a reinforcing bar nut 74, which allows the reinforcing bar to pass through the fixing plate and the fixing head to connect with the seismic testing equipment. The rubber pad can absorb shock and prevent damage to the device, while the ball joint can make the concrete more tightly fixed.

[0028] The above description is merely a preferred embodiment of this utility model. The protection scope of this utility model is not limited to the above embodiments. All technical solutions falling within the scope of this utility model's concept are protected by this utility model. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of this utility model should also be considered within the protection scope of this utility model.

Claims

1. A cracked concrete structure for seismic testing, characterized in that: It includes a concrete layer and several pre-embedded longitudinal steel bars. An isolation sleeve is pre-embedded at the junction of the longitudinal steel bars and the pre-opening plane. The longitudinal steel bars pass through the isolation sleeve and both ends of the longitudinal steel bars protrude out of the concrete layer. A guide board is also pre-embedded in the concrete layer. The guide board is located in the lower half of the pre-opening plane.

2. A cracked concrete structure for seismic testing as described in claim 1, characterized in that: The guide wooden board is oriented in the same direction as the pre-slit plane and is perpendicular to the longitudinal reinforcing bars.

3. A cracked concrete structure for seismic testing as described in claim 1, characterized in that: The concrete layer has planned pre-opening joint positions, which extend into the concrete layer to form a pre-opening joint plane. The longitudinal reinforcing bars are separated from the pre-opening joint plane by isolation sleeves.

4. A cracked concrete structure for seismic testing as described in claim 1, characterized in that: The diameter of the longitudinal reinforcing bar is 40mm.

5. A cracked concrete structure for seismic testing as described in claim 1, characterized in that: The longitudinal reinforcing bars are connected to the seismic testing equipment via a fixing plate and a fixing head; the fixing plate is provided with several reserved holes for the longitudinal reinforcing bars to pass through.

6. A cracked concrete structure for seismic testing as described in claim 5, characterized in that: The fixing head includes a steel bar nut, a ball joint, a steel plate, and a rubber pad. The longitudinal steel bar passes through the rubber pad, the steel plate, and the ball joint in sequence and is then locked in place with the steel bar nut.

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