Concrete bonding strength testing device
By designing a bond strength testing device for spraying concrete, the concrete core sample is directly pulled out to solve the problems of complex, time-consuming and low accuracy of existing detection methods, and efficient and accurate detection results are achieved.
Patent Information
- Application Number
- CN202321728505.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Priority Date
- 2022-11-01
- Filing Date
- 2023-07-04
- Publication Date
- 2025-05-13
- Estimated Expiration
- 2033-07-04
AI Technical Summary
The existing spray concrete bond strength detection methods are complex, time-consuming, low precision, and require steps such as planting tendons to increase operational complexity and error.
A concrete bond strength test device was designed. The core sample was drilled on the concrete surface by drilling the core cylinder and directly pulling the core sample, avoiding the steps of planting the ribs and waiting for solidification, and simplifying the operation.
It realizes concrete bond strength testing with short inspection time, simple operation and high accuracy, shortens construction period and improves work efficiency.
Smart Images
Figure CN222866391U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of concrete bonding strength detection, in particular to a concrete bonding strength testing device. Background Art
[0002] As a common form of engineering support, shotcrete is widely used in geotechnical engineering, tunnel engineering, municipal engineering and slope engineering. Shotcrete has the advantages of simple construction, rapid initial strength improvement, good impermeability, etc., especially it can fill the gaps and surface pits of the rock mass, and re-bond the separated stress surfaces together. The bonding of the sprayed layer and the surrounding rock will form a common working surface, improve the resistance and support of the structural surface, and avoid or alleviate the stress concentration phenomenon of the sprayed structure, which can greatly improve the stability and safety of the structure. Therefore, the bond strength between shotcrete and surrounding rock is an important parameter for evaluating whether shotcrete can fully play its role.
[0003] The strength of concrete after solidification needs to be tested before subsequent construction can continue. The current on-site testing method mainly uses the core drilling and pulling method. The main operating steps of the existing core drilling and pulling method are as follows: 1. Select the test location, use a drill to drill perpendicular to the shotcrete layer and penetrate more than 20mm into the surrounding rock to form a cylindrical core sample with a bonding surface between the shotcrete and the surrounding rock; 2. Disassemble the drill; 3. Use an impact drill to plant reinforcement at the test location as the force-transmitting reinforcement for the pull-out test, and wait for the adhesive used for planting reinforcement to solidify, which will solidify after about 7-14 days, and then conduct a pull-out test; 4. Install a puller and slowly apply tension to the steel bar until the core sample is destroyed along the bonding surface between the shotcrete and the surrounding rock; 5. Calculate the bonding strength between the shotcrete and the surrounding rock by the tension and the fractured cross-sectional area.
[0004] This method has many disadvantages. Ordinary core drilling machines can only take cores, and the gap formed after taking cores is small. The core barrel has no fixed core sample device and pulling equipment, and the pulling test cannot be carried out directly after taking cores, which increases the test operation steps and is time-consuming and labor-intensive. The existing detection method has low detection accuracy and requires pre-embedded reinforcement. The strength tested by implanted reinforcement is different from the actual strength of concrete tested directly. Embedded reinforcement is also ductile. There will be deviations in the bond strength of concrete tested by implanted reinforcement. Moreover, it is difficult to ensure that the implanted reinforcement is positioned at the center of the core sample, and it is often eccentrically pulled, resulting in detection errors. The results are highly deviated, and the rebars are prone to loosening, resulting in test failures. The operation is complex, and many equipment and labor are required, including drilling rigs, impact drills, pullers, etc. There is no integrated equipment, which greatly reduces work efficiency. It is also necessary to wait for the rebars to solidify, which takes a long time, and the preparation work is complicated. The equipment involved is used repeatedly, and the turnaround time is wasted. The test can only be started after the bonding material of the rebars reaches a certain strength. The preliminary work takes a long time, and all projects need to wait for the bonding strength results of the concrete and the rock formation before subsequent construction, which affects the construction progress of the entire project. Now we need a more accurate, less time-consuming, and simpler way to test the strength of concrete.
[0005] Based on this, the utility model designs a concrete bonding strength testing device to solve the above problems. Summary of the invention
[0006] The purpose of the utility model is to provide a concrete bonding strength testing device, which can test the bonding strength of concrete and rock formations without the need to plant reinforcement in concrete. Therefore, there is no need to wait for the solidification of the planted reinforcement, which shortens the solidification time of the planted reinforcement, effectively shortens the testing time and the engineering construction time, and does not need to use a drilling rig and an impact drill. The operation is more convenient, and the strength of the concrete is directly tested. The test object is directly tested, avoiding indirect strength testing through planted reinforcement, so that the strength test of the concrete by the device is more accurate.
[0007] The utility model is implemented as follows: a concrete bonding strength testing device, comprising:
[0008] Drill core barrel, support base, fixed frame rod, control switch, anchor base and drilling motor;
[0009] The core drilling barrel is an open cylindrical structure with a hollow interior, a plurality of core extraction grooves are evenly arranged at the same height position of the inner arc wall of the core drilling barrel, a plurality of drill bits are evenly arranged on the annular surface at the lower opening of the core drilling barrel, the upper end of the core drilling barrel is closed, and a connecting block is fixedly arranged on the outer portion of the upper end of the core drilling barrel;
[0010] A core pulling block is rotatably arranged inside each core pulling groove, a positioning block is also arranged inside the core pulling groove, an adjusting rod is connected to the upper end of the positioning block, the upper end of the adjusting rod extends out of the top of the core drilling barrel, the adjusting rod can be lifted up and down and is arranged inside the wall of the core drilling barrel, and the adjusting rod is locked with the core drilling barrel through an adjusting nut;
[0011] The positioning block is clamped between the bottom of the core pulling groove and the inner side of the core pulling clamping block, and the upper end of the core pulling clamping block and the positioning block can be squeezed and retracted to extend out of the hollow hole of the core drilling tube;
[0012] The support base is a stable frame, a dynamometer is stably mounted inside the support base, a drilling motor is detachably locked under the dynamometer, and the drilling motor is locked and mounted on the connecting block;
[0013] The anchor seat is a stably erected base, and the anchor seat can be detachably locked on the concrete surface to be tested. There are two anchor seats, and a fixed frame rod is vertically erected on the top of each anchor seat, and a telescopic rod is vertically telescopically arranged on the top of each fixed frame rod. A lifting frame is horizontally erected between the two telescopic rods on the two anchor seats, and the control switch is a controller of the two telescopic rods, and the support seat is fixed on the lifting frame;
[0014] The axis of the core drill barrel, the driving shaft of the drilling motor and the pulling direction of the dynamometer coincide with each other, and the fixed frame rod and the axis of the core drill barrel are parallel on the same vertical plane.
[0015] Furthermore, the adjusting nut is arranged outside the top end of the core drilling barrel, the upper end of the adjusting rod is locked with the adjusting nut through a thread, and the adjusting rod is lifted and lowered in the wall of the core drilling barrel by rotating and locking the adjusting nut;
[0016] The positioning block is a sphere, the core pulling block is a wedge-shaped block, the tip of the core pulling block is arranged toward the upper end of the core drilling barrel, the inner side surface of the core pulling block is an arc surface with a larger upper portion and a smaller lower portion, the sum of the diameter of the positioning block and the thickness of the upper end of the core pulling block is greater than the depth c of the core pulling groove, and the sum of the diameter of the positioning block and the thickness of the lower end of the core pulling block is less than the depth c of the core pulling groove;
[0017] The core pulling groove is provided with a rotating pin, the rotating pin and the axis of the core drilling tube are perpendicular to each other in the same vertical plane, and the core pulling block can be turned horizontally toward the inside of the core drilling tube through the rotating pin and is arranged in the core pulling groove.
[0018] Furthermore, the drill bit is tilted toward the hollow hole of the core drilling barrel, the drill bit is inserted into the hole of the core drilling barrel, and the length of the drill bit inserted into the inner hole of the core drilling barrel is d, and d does not exceed 2 cm;
[0019] The length of the core pulling block extending into the inner wall of the core pulling groove is s, and the length d is smaller than s.
[0020] Furthermore, a water inlet hole is provided on the closed end of the core drilling barrel, and the water inlet hole is connected between the upper end exterior and the hollow inner hole of the core drilling barrel.
[0021] Furthermore, a threaded hole is provided at the outer end of the connection block, a driving rod is installed on the driving shaft of the drilling motor, and the connection block and the driving rod are locked by threads.
[0022] Furthermore, the dynamometer is an anchor puller, the pulling end of the dynamometer is connected to a connecting piece, the connecting piece is tightly locked with the drilling motor, and the pulling direction of the dynamometer, the connecting piece and the driving shaft of the drilling motor are on the same straight line.
[0023] Furthermore, the fixed frame rod and the telescopic rod form a complete telescopic rod, the two sides of the lifting frame are locked on the top of the telescopic rods on both sides, the two telescopic rods are parallel to each other, and the two telescopic rods are vertically telescoped synchronously.
[0024] The beneficial effects of the utility model are as follows: 1. The utility model uses a core drill to drill a core sample on the concrete surface, and then directly pulls the core sample. There is no need to drill holes and plant reinforcement on the tested concrete surface, nor is there any need to wait for the reinforcement to solidify. The detection time is short and the detection operation is simple. After the test is completed, subsequent construction can be carried out directly, which plays a positive role in shortening the construction period.
[0025] 2. This device does not require an impact drill or a core drill, so the operation is simpler and more convenient, and the number of operators required is reduced, which improves work efficiency;
[0026] 3. This device does not conduct pull-out test on the embedded steel bars, but directly tests the concrete core samples, thereby realizing direct test of the bonding strength between concrete and rock formations. The test object is more direct, the test result is more accurate, and there is no need to consider whether the embedded steel bars are in the center of the core sample. This device evenly clamps the side walls of the core sample to make the force more uniform, thus avoiding the problem of eccentric tilt and skew force of the embedded steel bars. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The present invention will be further described below in conjunction with the embodiments with reference to the accompanying drawings.
[0028] Figure 1 This is a schematic diagram of the overall assembly structure of the utility model;
[0029] Figure 2 This is a schematic top view of the overall assembly of the utility model;
[0030] Figure 3 This is a schematic diagram of the internal structure of the core drilling tube of the utility model;
[0031] Figure 4 This is a schematic diagram of the distribution of the core extraction grooves on the side wall of the core drilling tube of the utility model;
[0032] Figure 5 This is a schematic diagram of the core pulling block of the utility model being retracted into the core pulling groove;
[0033] Figure 6 This is a schematic diagram of the core pulling clamping block of the utility model extending out of the core pulling groove and being locked;
[0034] Figure 7 This is a schematic diagram of the drill bit distribution of the core drilling barrel of the utility model;
[0035] Figure 8 It is a front structural schematic diagram of a core pulling block in a core pulling groove of the utility model.
[0036] In the accompanying drawings, the components represented by the reference numerals are listed as follows:
[0037] 1-core drilling barrel, 11-core extraction groove, 111-core extraction block, 112-adjusting nut, 113-positioning block, 114-adjusting rod, 115-rotating pin, 12-drill bit, 13-connecting block, 14-water inlet hole, 2-support seat, 21-pull connection piece, 22-dynamometer, 3-fixed frame rod, 31-telescopic rod, 32-control switch, 33-anchor seat, 34-lifting frame, 4-drilling motor, 41-driving rod. DETAILED DESCRIPTION
[0038] See also Figures 1 to 8 As shown, the utility model provides a technical solution: a concrete bonding strength testing device, comprising:
[0039] A core drill barrel 1, a support base 2, a fixed frame rod 3, a control switch 32 and a drilling motor 4;
[0040] The core drilling barrel 1 is a cylindrical structure with an open lower end and a hollow interior. A plurality of core extraction grooves 11 are evenly provided at the same height position of the inner arc wall of the core drilling barrel 1. A plurality of drill bits 12 are evenly arranged on the annular surface at the lower end opening of the core drilling barrel 1. The upper end of the core drilling barrel 1 is closed, and a connecting block 13 is fixedly provided on the outer upper end of the core drilling barrel 1.
[0041] A core pulling block 111 is rotatably arranged inside each core pulling groove 11, and a positioning block 113 is also arranged inside the core pulling groove 11. An adjusting rod 114 is connected to the upper end of the positioning block 113. The upper end of the adjusting rod 114 extends out of the top of the core drilling barrel 1. The adjusting rod 114 can be lifted up and down and is arranged inside the wall of the core drilling barrel 1. The adjusting rod 114 is locked with the core drilling barrel 1 through an adjusting nut 112.
[0042] The positioning block 113 is clamped between the bottom of the core pulling groove 11 and the inner side of the core pulling clamp 111. The upper end of the core pulling clamp 111 and the positioning block 113 can be squeezed and retracted to extend out of the hollow hole of the core drilling barrel 1.
[0043] The support base 2 is a stable frame, a dynamometer 22 is stably mounted inside the support base 2, a drilling motor 4 is detachably locked under the dynamometer 22, and the drilling motor 4 is locked and mounted on the connecting block 13;
[0044] The anchor seat 33 is a stably erected base, and the anchor seat 33 can be detachably locked on the concrete surface to be tested. There are two anchor seats 33, and a fixed frame rod 3 is vertically erected on the top of each anchor seat 33. A telescopic rod 31 is vertically telescopically arranged on the top of each fixed frame rod 3. A lifting frame 34 is horizontally erected between the two telescopic rods 31 on the two anchor seats 33. The control switch 32 is a controller of the two telescopic rods 31. The support seat 2 is fixed on the lifting frame 34. The telescopic rod 31 is started and stopped by the control switch 32. The support seat 2 is fixed on the lifting frame 34, and the drilling motor of the support seat 2 is arranged downward;
[0045] The axis of the core drill barrel 1, the driving shaft of the drilling motor 4 and the pulling direction of the dynamometer 22 coincide with each other, and the fixed frame rod 3 is parallel to the axis of the core drill barrel 1 in the same vertical plane. Therefore, there is no need to plant reinforcement in the concrete to test the bonding strength between the concrete and the rock formation. Therefore, there is no need to wait for the solidification of the reinforcement, which shortens the solidification time of the reinforcement, effectively shortens the test time and the construction time, and does not need to use a drilling rig and an impact drill. The operation is more convenient, and the strength of the concrete is directly tested. The test object is directly tested, avoiding indirect strength testing through reinforcement planting, so that the strength test of the concrete by the device is more accurate.
[0046] The adjusting nut 112 is arranged at the top of the upper end of the core drilling barrel 1, and the adjusting rod 114 is a screw rod, and the adjusting rod 114 is rotated and lifted in the wall of the core drilling barrel 1 through the thread;
[0047] The positioning block 113 is a sphere, the core pulling block 111 is a wedge-shaped block, the tip of the core pulling block 111 is arranged toward the upper end of the core drilling barrel 1, the inner side surface of the core pulling block 111 is an arc surface with a larger upper portion and a smaller lower portion, the sum of the diameter of the positioning block 113 and the thickness of the upper end of the core pulling block 111 is greater than the depth c of the core pulling groove 11, and the sum of the diameter of the positioning block 113 and the thickness of the lower end of the core pulling block 111 is less than the depth c of the core pulling groove 11;
[0048] The core pulling groove 11 is provided with a rotating pin 115, and the rotating pin 115 and the axis of the core drilling barrel 1 are perpendicular to each other in the same vertical plane. The core pulling block 111 can be horizontally turned inside the core drilling barrel 1 by the rotating pin 115 and is arranged in the core pulling groove 11. Through such a structure, the knob adjustment nut 112 can be turned outside the core drilling barrel 1, and the adjustment rod 114 can be pulled to adjust the position relationship between the positioning block 114 and the core pulling block 111, so as to adjust the core pulling block 111 to extend inwardly into the inner hole of the core drilling barrel 1, or the core pulling block 111 can be retracted into the core pulling groove 11;
[0049] The drill bit 12 is tilted toward the hollow hole of the core drilling barrel 1, and the drill bit 12 extends into the hole of the core drilling barrel 1, and the length of the drill bit 12 extending into the inner hole of the core drilling barrel 1 is d, and d does not exceed 2 cm;
[0050] The length of the core pulling block 111 extending into the inner wall of the core pulling groove 11 is s, and the length d is less than s, which facilitates the separation of the interior of the core drilling barrel 1 from the concrete core sample, thereby conveniently measuring the force of the concrete, and enables the core pulling block 111 to clamp and pull the core sample to prevent the core sample from loosening and being unable to be clamped;
[0051] A water inlet hole 14 is provided on the closed end of the core drill barrel 1. The water inlet hole 14 is connected between the upper end exterior and the hollow inner hole of the core drill barrel 1. The water inlet hole 14 can cool the drill bit 12 at the lower end of the core drill barrel 1 and prevent excessive internal pressure of the borehole.
[0052] A threaded hole is provided at the outer end of the connection block 13, and a driving rod 41 is installed on the driving shaft of the drilling motor 4. The connection block 13 and the driving rod 41 are locked by threads, which facilitates the connection and driving of the drilling motor 4 and facilitates drilling holes on the concrete surface.
[0053] The dynamometer 22 is an anchor puller. The pulling end of the dynamometer 22 is connected to the puller 21. The puller 21 is tightly locked with the drilling motor 4. The pulling direction of the dynamometer 22, the puller 21 and the driving shaft of the drilling motor 4 are in the same straight line, which is convenient for stable pulling test, accurate force measurement, and can record numerical values, which is convenient for calculating the required bonding strength parameters of concrete and rock formation. The axis coincides to ensure the accuracy of the pulling direction and avoid deflection.
[0054] The fixed frame rod 3 and the telescopic rod 31 form a complete telescopic rod, which can be an electric telescopic rod, a hydraulic telescopic rod, or even a commonly used screw lifting mechanism, as long as it can meet the working intensity and environmental requirements of the device. The lifting frame 34 is horizontally mounted on the fixed frame rod 3 and lifted by the telescopic rod 31, which facilitates the extension and retraction of the telescopic rod 31 without affecting the lifting of the lifting frame 34, thereby driving the lifting frame 34 to rise and fall.
[0055] In a specific embodiment of the present invention:
[0056] The embodiment of the utility model provides a concrete bonding strength testing device. The existing method of drilling and pulling to test the bonding strength of concrete is to drill holes and take cores from the solidified concrete again, then plant the steel bars, wait for 7-14 days for the planted steel bars and the concrete core sample to solidify as a whole, and then pull out the planted steel bars. The technical problems encountered by the utility model are: 1. Such drilling, coring and planting and solidification operations are very cumbersome, and the concrete is easily damaged during the planting process, resulting in the need for re-operation, which is time-consuming and laborious; 2. This testing method is time-consuming and It is difficult to immediately detect the firmness of the embedded steel bars. Often, when the test is finally conducted, it is found that the embedded steel bars are unqualified and it is necessary to operate again, which is time-consuming. 3. The holes for embedded steel bars are drilled by humans, so the drilling accuracy cannot be guaranteed and it is easy for the holes to deviate. The deviated embedded steel bars will be subjected to uneven force during pulling, which will directly lead to inaccurate pulling force and large deviations. 4. The pulling of embedded steel bars is not a direct pulling of the shotcrete core sample. The embedded steel bars also have certain strength and ductility. Pulling the embedded steel bars will cause deviations in the test data of the concrete bonding strength.
[0057] The technical problem solved by the utility model is: directly testing the concrete itself, and drilling the core of the concrete surface through simple equipment, without the need for planting reinforcement, the operation is simpler, and the test of the pull-out force is instantaneous, the value can be known immediately, and there is no need to wait.
[0058] The technical effects achieved are as follows: 1. The utility model uses the core drill tube 1 to drill a core sample on the concrete surface, and then directly pulls the core sample. There is no need to drill holes and plant reinforcement on the tested concrete surface, nor is there any need to wait for the reinforcement to solidify. The detection time is short and the detection operation is simple. After the test is completed, subsequent construction can be carried out directly, which plays a positive role in shortening the construction period.
[0059] 2. This device does not require an impact drill or a core drill, but uses a core drill barrel 1 to directly drill the concrete surface, which is simpler and more convenient to operate, reduces the number of operators required, and improves work efficiency;
[0060] 3. This device no longer needs to conduct pull-out tests on the embedded steel bars, but directly tests the concrete core samples, thereby realizing a direct test of the bonding strength between concrete and rock formations. The test object is more direct, the test results are more accurate, and there is no need to consider whether the embedded steel bars are in the center of the core sample. This device evenly clamps the side walls of the core sample to make the force more uniform, thus avoiding the problem of eccentric tilt and skew force of the embedded steel bars.
[0061] The technical solution in the embodiment of the utility model is to solve the above problems, and the overall idea is as follows:
[0062] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.
[0063] When manufacturing the utility model, a support base 2 of a frame structure is first manufactured, a lifting frame 34 is fixed on the support base 2, and the lifting frame 34 is laterally extended at both ends of the support base 2, and a dynamometer 22 is installed inside the support base 2, and the dynamometer 22 is an anchor rod pulling instrument, and a pulling end of the dynamometer 22 is also connected to a pulling piece 21;
[0064] Anchor puller is a necessary field testing instrument for quality inspection units. It is mainly used to detect the anchoring force of various anchors, steel bars and other anchoring bodies. Anchor puller is a necessary field testing instrument for quality inspection units. Anchor puller is mainly used to detect the anchoring force of various anchors, steel bars and other anchoring bodies. Anchor puller consists of a manual pump, a hydraulic cylinder, an intelligent digital pressure gauge, a high-pressure oil pipe with a quick connector, an anchor and a portable case. The hydraulic cylinder is a hollow self-resetting type, and the intelligent digital pressure gauge can directly read the anchor tension value, and has peak holding, storage and query functions. It is particularly suitable for field use and is easy to operate. The anchor pulled by the dynamometer 22 of this device is the connecting piece 21, and one end of the connecting piece 21 is locked with the dynamometer 22, and the other end is set and locked on the body of the drilling motor 4. The driving shaft of the drilling motor 4 is a driving rod 41, and the driving end of the driving rod 41 is a screw, and the driving rod 41 is locked to the closed end of the core barrel 1;
[0065] The upper end of this device is Figure 1 The closed end of the core drill tube 1 is also one end of the support seat 2, and the support seat 2 is located above the core drill tube 1. The lower end of the device refers to one end of the drill bit 12, that is, the end that is in contact with the concrete surface for drilling.
[0066] Two sets of anchoring seats 33 for fixing the device are also required to be made. The anchoring seat 33 is a flat structural base. The anchoring seat 33 can be detachably locked on the concrete surface to be tested by expansion bolts. A fixing frame rod 3 is vertically fixed on the anchoring seat 33, that is, the fixing frame rod 3 needs to be perpendicular to the top plane of the anchoring seat 33. The anchoring seat 33 needs to be attached to the test surface of the concrete for anchoring and locking, and the fixing frame rod 3 needs to be perpendicular to the plane where the anchoring seat 33 is located, that is, the fixing frame rod 3 needs to be perpendicular to the concrete surface to be tested. There are two anchoring seats 33, and a fixing frame rod 3 is vertically erected on the top of each of the anchoring seats 33. A telescopic rod 31 is set on the top of each of the fixing frame rods 3, which can be vertically telescopic. The two anchoring seats 33 are A lifting frame 34 is horizontally set up between the two telescopic rods 31, and the control switch 32 is a controller of the two telescopic rods 31. The support seat 2 is fixed on the lifting frame 34, and the lifting frame 34 needs to be locked with the upper end of the telescopic rod 31 as an integral structure. The lifting frame 34 needs to be kept parallel to the anchor seat 33, that is, the lifting frame 34 needs to be kept parallel to the concrete test surface, and a control switch 32 needs to be installed on the telescopic rod 31 on one of the anchor seats 33. The control switch 32 can control the telescopic rod 31 to drive the extension and contraction, so that the lifting frame 34 is lifted and lowered, which is convenient for lifting and lowering the entire support seat 2 and the core drilling barrel 1 to fit the concrete surface, and the two telescopic rods 31 need to be kept synchronous when extending and contracting, and it is determined that the lifting frame 34 is kept horizontal when being lifted and lowered;
[0067] After the external support and lifting structure are erected, it is necessary to make a core drill barrel 1. The core drill barrel 1 is a cylindrical structure. The upper end of the core drill barrel 1 is closed and the lower end is open. The core drill barrel 1 is a hollow cylinder. A plurality of drill bits 12 are evenly arranged on the annular surface at the lower end opening of the core drill barrel 1. The drill bits 12 are inclined toward the hollow hole of the core drill barrel 1. The drill bits 12 extend into the hole of the core drill barrel 1, and the length of the drill bits 12 extending into the inner hole of the core drill barrel 1 is d, and d does not exceed 2 cm; the length of the core pulling block 111 extending into the inner wall of the core pulling groove 11 is s, and the length d is less than s;
[0068] As long as it extends out into the inner hole of the core barrel 1, it is ensured that the drill bit 12 can leave a certain gap between the drilled core sample and the inner wall of the core barrel 1 to avoid the core sample being affected by the core barrel 1 when pulling. The drill bit 12 also needs some drill bits to extend out of the outer wall of the core barrel 1 to separate the outer wall of the core barrel 1 from the concrete layer, so that the core barrel 1 can be pulled out after the test is completed; the drill bit 12 also has multiple drill bits 12 with different directions, and multiple drill bits 12 are inclined to the outside of the wall of the core barrel 1, so that the concrete core can be effectively separated from the original sprayed concrete wall or ground through multiple drill bits 12 in different directions to form a fault, so that the core sample used for concrete testing can be pulled and the pull-out force can be tested without interfering with the redundant connection, and the data is more accurate.
[0069] The core drill barrel 1 has an open lower end and a hollow cylindrical structure. The inner diameter of the core drill barrel 1 can be 60 to 200 mm. The drilling pulling depth is determined by evenly disposing a plurality of core pulling grooves 11 at the same height position on the hollow inner wall of the cylinder of the core drill barrel 1. The upper end of the core drill barrel 1 is closed. A connecting block 13 is fixedly disposed on the outer upper end of the core drill barrel 1. A screw hole is disposed at the center of the upper end of the connecting block 13. The connecting block 13 is locked with the driving rod 41, so that the drilling motor 4 can drive the core drill barrel 1 to drill holes.
[0070] The number of the core-pulling grooves 11 is between 4 and 12, depending on the size of the core-pulling grooves 11 and the diameter of the core-drilling tube 1, and the optimal number of the core-pulling grooves 11 is 6 or 8, which are symmetrically arranged so that the cut concrete core is subjected to more uniform force;
[0071] Each core pulling groove 11 is provided with a rotating pin 115, and the rotating pin 115 is provided in the core pulling groove 11, and the rotating pin 115 and the axis of the core drilling tube 1 are perpendicular to each other in the same vertical plane, and the core pulling block 111 can be horizontally turned inside the core drilling tube 1 by the rotating pin 115.
[0072] A core pulling block 111 is rotatably installed in each core pulling groove 11 through a rotating pin 115, and a positioning block 113 is also provided in the core pulling groove 11. An adjusting rod 114 is connected to the upper end of the positioning block 113. The upper end of the adjusting rod 114 extends out of the top of the core drilling tube 1. The adjusting rod 114 can be lifted up and down and is arranged inside the wall of the core drilling tube 1. The adjusting rod 114 is locked with the core drilling tube 1 through an adjusting nut 112. The adjusting rod 114 is a smooth rod. The end of the adjusting rod 114 extending out of the top of the core drilling tube 1 has a thread. The thread on the upper end of the adjusting rod 114 is locked and adjusted with the adjusting nut 112. By rotating and pulling the adjusting nut 112, the adjusting rod 114 is pulled out upward, so that the positioning block 113 and the upper end of the core pulling block 111 are stuck against each other, and the adjusting nut 112 is rotated to loosen the adjusting nut 112, so that the adjusting rod 114 can be pushed downward, so that the core pulling block 111 and the positioning block 113 are loosened from each other.
[0073] The positioning block 113 is clamped between the bottom of the core pulling groove 11 and the inner side of the core pulling block 111, and the upper end of the core pulling block 111 and the positioning block 113 can be squeezed and retracted to extend out of the hollow hole of the core drilling barrel 1; the adjusting nut 112 is arranged on the top of the upper end of the core drilling barrel 1, and the adjusting rod 114 is a screw rod, and the adjusting rod 114 is rotated and lifted in the wall of the core drilling barrel 1 through a thread;
[0074] Another installation method of the adjusting rod 114 is that the adjusting rod 114 can also be a whole screw rod. The adjusting rod 114 is installed in the core drilling tube 1 through a thread. An adjusting nut 112 is fixedly welded on the outside of the adjusting rod 114. The adjusting rod 114 is rotated by rotating the adjusting nut 112 to make the adjusting rod 114 rise and fall in the core drilling tube 1, thereby driving the positioning block 113 to rise and fall. The structure of this device only needs to drive the positioning block 113 to rise and fall and press against the upper end of the core pulling block 111, and ensure that the core pulling block 111 is pushed out and clamped or loosened so that the core pulling block 111 is retracted into the core pulling groove 11, and the clamping is more compact; the adjusting rod 114 is made of a material with high rigidity, small deformation and temperature insensitivity. The steel bar should have good rigidity so that it can push or pull back the positioning ball without or less deformation, bending and other adverse actions that affect the operation effect.
[0075] The positioning block 113 is a sphere, the core pulling block 111 is a wedge-shaped block, the tip of the core pulling block 111 is arranged toward the upper end of the core drilling barrel 1, the inner side surface of the core pulling block 111 is an arc surface with a larger upper portion and a smaller lower portion, the sum of the diameter of the positioning block 113 and the thickness of the upper end of the core pulling block 111 is greater than the depth c of the core pulling groove 11, the sum of the diameter of the positioning block 113 and the thickness of the lower end of the core pulling block 111 is less than the depth c of the core pulling groove 11, and the length d is less than s, so that the length s of the core pulling block 111 extending out to clamp the concrete core is greater than the gap d drilled by the drill bit 12, ensuring that the core pulling block 111 can clamp the concrete core sample for pulling;
[0076] A water inlet hole 14 is also provided on the closed end of the core drill barrel 1 , and the water inlet hole 14 is connected between the upper end exterior and the hollow inner hole of the core drill barrel 1 , so as to facilitate water injection into the core drill barrel 1 to cool the drill bit 12 .
[0077] When the utility model is in use, the device can detect vertical concrete walls and horizontal ground. During operation, it is only necessary to lock the anchor seat 33 on the concrete surface to be tested by means of expansion screws, and then ensure that the lifting frame 34 is at the same height position as the fixed frame rod 3, and then control the control switch 32 to drive the telescopic rod 31 to make the drill bit 12 fit with the concrete surface, and then turn on the drilling motor 4, the drilling motor 4 drives the core drill 1 to make the core drill 1 drill the concrete surface, and the inner hole of the core drill 1 is the drilled concrete core sample, and then continue to operate the control switch 32 to control the telescopic rod 31 to make the lifting frame 34 move toward the concrete surface. Direction descending, during the detection test, the distance between the selected core pulling block 111 and the top of the core drilling tube 1 is determined according to the designed thickness of the sprayed concrete layer. For example, if the designed thickness of the sprayed concrete layer is 30 cm, the core pulling block 111 is selected to be 20 cm away from the top of the core drilling tube 1; if the designed thickness of the sprayed concrete layer is 50 cm, the core pulling block 111 is selected to be 40 cm away from the top of the core drilling tube 1. The drilling depth needs to be greater than the thickness of the concrete layer, that is, the pulling depth is 10 cm less than the set thickness of the sprayed concrete, and the drilling depth only needs to ensure this depth. The thickness of the sprayed concrete layer is preset and fixed before pouring, and the depth between the core pulling block 111 and the end face of the drill bit 12 of the core drilling tube 1 is also fixed, and it is only necessary to ensure the drilling depth.
[0078] Then rotate all the adjusting nuts 112 to raise the connecting block 13, so that the connecting block 13 and the upper end of the core pulling block 111 are squeezed and abutted against each other, and the wedge-shaped tip of the core pulling block 111 is pushed out, so that the wedge-shaped tip of the core pulling block 111 is pressed against the side wall of the concrete core sample drilled by the core drilling tube 1, and then turn on the dynamometer 22. The dynamometer 22 is an anchor puller with a hydraulic jacking device inside. The dynamometer 22 pulls the core drilling tube 1 and the drilling motor 4, and continuously applies force to pull the drilled concrete core sample. When the pulling force no longer increases, turn off the dynamometer 22; record the maximum force value, rotate the adjusting rod 114, so that the positioning block 113 and the core pulling block 111 are loosened and not abutted against each other, and the core pulling block 111 is retracted into the core pulling groove 11, so that the equipment can be disassembled and the test is completed.
[0079] Because this device is designed for the bond strength test of shotcrete, the strength of the fixed frame rod 3 and the anchor puller used are based on the bond strength between concrete and rock formations, so it is only suitable for the bond strength test between concrete and rock formations. This device is also developed to address the technical problems encountered in concrete testing, including the pull-out test method, which is also a conventional test method for concrete bond strength testing in this field.
[0080] In addition, in the description of the present invention, it should be noted that if the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", "front", "back", "top", "bottom", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.
[0081] Although the specific implementation methods of the present invention are described above, those skilled in the art should understand that the specific embodiments described are only illustrative and are not intended to limit the scope of the present invention. Equivalent modifications and changes made by those skilled in the art in accordance with the spirit of the present invention should be included in the scope of protection of the claims of the present invention.
Claims
1. A concrete bonding strength testing device, characterized in that: include: A core drill barrel (1), a support seat (2), a fixed frame rod (3), a control switch (32), an anchor seat (33) and a drilling motor (4); The core drilling barrel (1) is a cylindrical structure with an open lower end and a hollow interior, a plurality of core extraction grooves (11) are evenly arranged at the same height position on the inner arc wall of the core drilling barrel (1), a plurality of drill bits (12) are evenly arranged on the annular surface at the lower opening of the core drilling barrel (1), the upper end of the core drilling barrel (1) is closed, and a connecting block (13) is fixedly arranged on the outer portion of the upper end of the core drilling barrel (1); A core pulling block (111) is rotatably arranged inside each core pulling groove (11), and a positioning block (113) is also arranged inside the core pulling groove (11). An adjusting rod (114) is connected to the upper end of the positioning block (113), and the upper end of the adjusting rod (114) extends out of the top of the core drilling barrel (1). The adjusting rod (114) is arranged inside the wall of the core drilling barrel (1) so as to be able to rise and fall, and the adjusting rod (114) is locked with the core drilling barrel (1) through an adjusting nut (112); The positioning block (113) is clamped between the bottom of the core pulling groove (11) and the inner side of the core pulling clamping block (111), and the upper end of the core pulling clamping block (111) and the positioning block (113) can be squeezed and retracted to extend out of the hollow hole of the core drilling barrel (1); The support base (2) is a stable frame, a dynamometer (22) is stably mounted inside the support base (2), a drilling motor (4) is detachably locked below the dynamometer (22), and the drilling motor (4) is locked and mounted on the connecting block (13); The anchor seat (33) is a stably erected base, and the anchor seat (33) can be detachably locked on the concrete surface to be tested. There are two anchor seats (33), and a fixed frame rod (3) is vertically erected on the top of each anchor seat (33). A telescopic rod (31) is vertically telescopically arranged on the top of each fixed frame rod (3). A lifting frame (34) is horizontally erected between the two telescopic rods (31) on the two anchor seats (33). The control switch (32) is a controller of the two telescopic rods (31), and the support seat (2) is fixed on the lifting frame (34); The axis of the core drill barrel (1), the driving shaft of the drilling motor (4) and the pulling direction of the dynamometer (22) coincide with each other, and the fixed frame rod (3) and the axis of the core drill barrel (1) are parallel on the same vertical plane.
2. A concrete bonding strength testing device according to claim 1, characterized in that: The adjusting nut (112) is arranged outside the top end of the core drilling tube (1), the upper end of the adjusting rod (114) is screw-locked with the adjusting nut (112), and the adjusting rod (114) is lifted and lowered in the wall of the core drilling tube (1) by rotating and locking the adjusting nut (112); The positioning block (113) is a spherical ball, the core pulling block (111) is a wedge-shaped block, the tip of the core pulling block (111) is arranged toward the upper end of the core drilling tube (1), the inner side surface of the core pulling block (111) is an arc surface with a larger upper portion and a smaller lower portion, the sum of the diameter of the positioning block (113) and the thickness of the upper end of the core pulling block (111) is greater than the depth c of the core pulling groove (11), and the sum of the diameter of the positioning block (113) and the thickness of the lower end of the core pulling block (111) is less than the depth c of the core pulling groove (11); The core pulling groove (11) is provided with a rotating pin (115), and the rotating pin (115) and the axis of the core drilling barrel (1) are perpendicular to each other in the same vertical plane. The core pulling block (111) is arranged in the core pulling groove (11) so as to be able to be turned horizontally toward the inside of the core drilling barrel (1) through the rotating pin (115).
3. A concrete bonding strength testing device according to claim 1, characterized in that: The drill bit (12) is arranged obliquely toward the hollow hole of the core drilling tube (1), the drill bit (12) extends into the hole of the core drilling tube (1), and the length of the drill bit (12) extending into the inner hole of the core drilling tube (1) is d, and d does not exceed 2 cm; The length of the core pulling block (111) extending into the inner wall of the core pulling groove (11) is s, and the length d is smaller than s.
4. A concrete bonding strength testing device according to claim 1, characterized in that: A water inlet hole (14) is provided on the closed end of the core drilling tube (1), and the water inlet hole (14) is connected between the upper end exterior and the hollow inner hole of the core drilling tube (1).
5. A concrete bonding strength testing device according to claim 1, characterized in that: A threaded hole is provided at the outer end of the connection block (13); a driving rod (41) is installed on the driving shaft of the drilling motor (4); and the connection block (13) and the driving rod (41) are locked by threads.
6. A concrete bonding strength testing device according to claim 1, characterized in that: The dynamometer (22) is an anchor rod pulling instrument. The pulling end of the dynamometer (22) is connected to a pulling member (21). The pulling member (21) is tightly locked with a drilling motor (4). The pulling direction of the dynamometer (22), the pulling member (21) and the driving shaft of the drilling motor (4) are on the same straight line.
7. A concrete bonding strength testing device according to claim 1, characterized in that: The fixed frame rod (3) and the telescopic rod (31) form a complete telescopic rod, the two sides of the lifting frame (34) are locked on the top of the telescopic rods (31) on both sides, the two telescopic rods (31) are parallel to each other, and the two telescopic rods (31) are synchronously telescoped vertically.