Intelligent anchor and method for testing anchor rod axial force

Abstract

The present invention relates to an intelligent anchor, comprising an anchor ring and a split anchor for clamping an anchor rod steel strand, wherein the anchor ring comprises a first anchor ring and a second anchor ring, wherein the first anchor ring and the second anchor ring are locked together by a connector, wherein the first anchor ring and the second anchor ring form an anchor installation slot for installing the split anchor, and further comprises a strain gauge for sensing the circumferential strain of the anchor ring, a compensation gauge for compensating for strain differences caused by temperature, and a data collector, wherein the strain gauge is connected to the data collector via a wire, and the strain gauge is fixed to the outer wall of the anchor ring along the circumferential direction of the anchor ring. The present invention also proposes a method for testing the axial force of an anchor rod using the anchor, and the present invention has the advantages of simple structure, convenient operation, and high measurement accuracy.

Description

Technical Field

[0001] The present invention relates to an intelligent anchor and a method for testing the axial force of an anchor rod, which is suitable for monitoring the axial force of an anchor rod in all temporary anchoring projects. By performing special content monitoring on the anchor and combining a theoretical calculation method, the axial force borne by the anchor rod can be obtained. The present invention can replace the traditional method of testing the axial force of an anchor rod by setting a dynamometer under the anchor. Background Art

[0002] In engineering construction, geotechnical anchoring projects are increasing, and the reusability of related materials is of great significance for saving resources. In geotechnical anchoring projects, due to the complexity of construction conditions, site environment, geological conditions, etc., the safety of anchor rods is directly related to the safety and stability of anchoring projects. The most important indicator for anchor rod safety monitoring is the monitoring of anchor rod axial force. At present, the monitoring of anchor rod axial force is mainly carried out by installing a dynamometer under the anchor of the anchor head to monitor the axial force of the anchor rod. This existing method has two main disadvantages: (1) The dynamometer is very expensive. Generally, the market price of a dynamometer is 900-3000 yuan, or even more expensive; and the dynamometer is a disposable product. The number of anchor rods in an anchoring project ranges from hundreds to thousands. It is difficult to monitor the axial force of a large number of anchor rods in batches. As a result, most actual projects adopt the method of monitoring a few anchor rods in a row of 1-3 sections. How does the axial force of most anchor rods that are not monitored change? Does the actual axial force exceed the design value? Is the actual axial force far lower than the design value? Is the axial force fluctuation abnormal? None of them are clear, which brings serious safety hazards to the project; (2) The size of the dynamometer is large, especially the axial length is long, which requires a certain amount of clearance, resulting in an increase in the clear distance between the supporting piles or supporting slope and the outer wall of the basement, increasing the amount of earth excavation and extending the construction period.

[0003] In view of this, the inventor of this case conducted in-depth research on the above-mentioned issues, which led to the emergence of this case. Summary of the invention

[0004] An object of the present invention is to provide an intelligent anchor with simple structure, convenient operation and high measurement accuracy. Another object of the present invention is to propose a method for testing the axial force of an anchor rod by using the anchor.

[0005] In order to achieve the above object, the present invention adopts such technical solution:

[0006] The intelligent anchor comprises an anchor ring and a split anchor for clamping an anchor steel strand, wherein the anchor ring comprises a first anchor ring and a second anchor ring, the first anchor ring and the second anchor ring are locked together by a connector, the first anchor ring and the second anchor ring form an anchor installation groove for installing the split anchor, and further comprises a strain gauge and a data collector for sensing the circumferential strain of the anchor ring, the strain gauge is connected to the data collector by a wire, and the strain gauge is fixed at the center of the outer wall of the locking ring of the anchor ring along the circumferential direction of the anchor ring.

[0007] As a preferred embodiment of the present invention, it further comprises a compensation sheet, which is fixed to the outer wall of the lock ring of the anchor ring along the axial direction of the anchor ring, and the compensation sheet is connected to the data collector.

[0008] As a preferred embodiment of the present invention, the split anchor comprises two identical first split anchors and one second split anchor, the second split anchor is arranged between the two first split anchors, the first split anchor is provided with a first semi-conical hole and a first semi-rebar-piercing hole, and the second split anchor is provided with a second semi-conical hole matching the first semi-conical hole and a second semi-rebar-piercing hole matching the first semi-conical hole on both sides, the first semi-conical hole and the second semi-conical hole form a conical hole, and each of the steel strands is installed in the conical hole through two clips.

[0009] As a preferred embodiment of the present invention, the first anchor ring and the second anchor ring both include a semicircular locking ring and locking ears arranged at both ends of the locking ring, the locking ears are provided with bolt through holes, and the connecting members are bolts and nuts.

[0010] As a preferred embodiment of the present invention, both ends of the second split anchor are provided with limiting tongues, and the limiting tongues are pressed against the upper end of the anchor ring.

[0011] As a preferred embodiment of the present invention, the strain gauge and the compensation gauge are fixed to the locking ring of the anchor ring by gluing.

[0012] As a preferred embodiment of the present invention, the strain gauge is a resistance strain gauge.

[0013] The present invention also proposes a method for testing the axial force of an anchor rod using an intelligent anchor, which uses the above-mentioned intelligent anchor and uses the following calculation method:

[0014] (1) Hoop strain of the outer wall of the first anchor ring The calculation formula is:

[0015] Calculation formula

[0016] Where: u ρ - radial displacement of the outer wall of the first anchor ring, m;

[0017] r2-outer diameter of the first anchor ring, m;

[0018] (2) Calculation formula for the radial displacement of the outer wall of the first anchor ring:

[0019]

[0020] Where: E-elastic modulus of the first anchor ring, kPa;

[0021] μ - Poisson's ratio of the first anchor ring;

[0022] q-confining pressure of the inner wall of the anchor ring, kPa;

[0023] r1-inner diameter of anchor ring, m;

[0024] (3) Obtain the hoop strain of the outer wall of the first anchor ring:

[0025]

[0026] (4) Obtain the inner wall confining pressure of the anchor ring:

[0027]

[0028] (5) Calculation formula of anchor bolt axial force N:

[0029] Abbreviated as

[0030] Where: β-inclination angle of the cone hole, degree;

[0031] - Hoop strain of the first anchor ring obtained by strain gauge testing;

[0032] h – height of anchor ring, m;

[0033] π – pi;

[0034] The k-axis force coefficient is obtained

[0035] α- Anchor ring shape coefficient, default value is 1.0; calibrated before leaving the factory.

[0036] The technical solution of the present invention has the following beneficial technical effects: (1) The split anchor, split anchor ring and strain gauges attached thereto are used to form an intelligent anchor, which can replace the traditional method of using a dynamometer to test the axial force of the anchor rod, and detect the annular strain data of the anchor ring through the strain gauge and transmit it to the data collector; (2) The traditional dynamometer is expensive, with a single market price of about 900-3000 yuan, while a single strain gauge is about 0.5-2.0 yuan, and the intelligent anchor can be recycled and reused, which significantly saves the project cost; since the intelligent anchor can be recycled and reused, the strain gauge is inexpensive, and the entire anchor rod axial force of the anchoring project can be monitored in real time. Once a dangerous situation is found, a timely and accurate warning can be issued to ensure the safety of the project. The present invention has been tried by users and the reaction effect is good. (3) In the anchor axial force calculation formula, the strain of the strain gauge can be collected in real time, and the other parameters are all known quantities. The anchor axial force coefficient can be calculated in advance based on the known parameters, and the anchor ring shape coefficient can be calibrated and determined before leaving the factory. After the parameters and coefficients are input and stored in the data acquisition system, the data acquisition device automatically calculates based on the strain gauge test value and outputs the anchor axial force value in real time. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a top view of the first embodiment of the self-unlocking anchor of the present invention in the locked state after assembly.

[0038] Figure 2 For the present invention Figure 1 Bottom view of .

[0039] Figure 3 For the present invention Figure 1 Front view of.

[0040] Figure 4 For the present invention Figure 1 Left view of .

[0041] Figure 5 This is a top view of the assembly of the first embodiment of the anchor ring of the present invention.

[0042] Figure 6 It is a top view of a first embodiment of the first anchor ring of the present invention.

[0043] Figure 7 It is a bottom view of a first embodiment of the first anchor ring of the present invention.

[0044] Figure 8 For the present invention Figure 6 Front view of.

[0045] Fig. 9 For the present invention Figure 6 Left view of .

[0046] Fig.10 It is a top view of a first embodiment of the second anchor ring of the present invention.

[0047] Fig.11 It is a bottom view of a first embodiment of the second anchor ring of the present invention.

[0048] Fig.12 For the present invention Fig.10 Front view of.

[0049] Fig.13 For the present invention Fig.10 Left view of .

[0050] Fig.14 This is a top view of the first embodiment of the split anchor of the present invention after assembly.

[0051] Fig.15 This is a bottom view of the first embodiment of the split anchor of the present invention after assembly.

[0052] Fig.16 This is a disassembled view of the first embodiment of the split anchor of the present invention.

[0053] Fig.17 It is a front view of a first embodiment of the first split anchor of the present invention.

[0054] Fig.18 It is a left view of the first embodiment of the first split anchor of the present invention.

[0055] Fig.19 It is a left view of the first embodiment of the second split anchor of the present invention.

[0056] Fig. 20 It is a front view of the T-shaped screw of the present invention.

[0057] Fig.21 It is a top view of the unlocked state of the first embodiment of the self-unlocking anchor of the present invention.

[0058] Fig. 22 This is a left view of the anchor ring unlocked state of the first embodiment of the self-unlocking anchor of the present invention.

[0059] Fig.23 This is a top view of the locked state of the second embodiment of the self-unlocking anchor of the present invention.

[0060] Fig.24 This is a top view of the first anchor ring of the second embodiment of the self-unlocking anchor of the present invention.

[0061] Fig.25 This is a bottom view of the first anchor ring of the second embodiment of the self-unlocking anchor of the present invention.

[0062] Fig.26 A top view of the second anchor ring of the second embodiment of the self-unlocking anchor of the present invention.

[0063] Fig. 27 A bottom view of the second anchor ring of the second embodiment of the self-unlocking anchor of the present invention.

[0064] Fig.28 It is a top view of the locked state of the third embodiment of the self-unlocking anchor of the present invention.

[0065] Fig.29 For the present invention Fig.28 Front view of.

[0066] Fig.30 For the present invention Fig.28 Left view of .

[0067] Fig.31 It is a top view of the third embodiment of the anchor ring of the present invention.

[0068] Fig.32 It is a front view of a third embodiment of the first split anchor ring of the present invention.

[0069] Fig.33 It is an exploded top view of the third embodiment of the split anchor of the present invention.

[0070] Fig.34 For the present invention Fig.33 AA cross-section diagram.

[0071] Fig.35 For the present invention Fig.33 BB cross-section diagram.

[0072] Fig.36 For the present invention Fig.33 CC cross-section diagram.

[0073] Fig.37 It is a top view of the intelligent anchor of the present invention.

[0074] Fig.38 For the present invention Fig.37 Front view of.

[0075] Fig.39 It is a simplified structural diagram of the monitoring system of the present invention.

[0076] In the figure:

[0077] 100 anchor rings

[0078] 110 first anchor ring 111 upper wedge platform 112 upper wedge surface 113 unlocking groove 114 upper end ring

[0079] 120 second anchor ring 121 lower wedge platform 122 lower wedge surface 123 screw hole 124 lower end ring

[0080] 130 Anchor installation slot

[0081] 101 lock ear 102 bolt hole 103 bolt 104 nut 105 lock ring

[0082] 200 split anchor 210 first split anchor 211 first semi-conical hole 212 first semi-rib-piercing hole 213 limiting tongue

[0083] 220 second split anchor 221 second semi-conical hole 222 second semi-rebar hole

[0084] 230 clip 231 cone 232 wing plate

[0085] 300 T-screw 310 nut part 320 screw part 330 screw part

[0086] 400 steel strand

[0087] 501 strain gauge 502 compensation sheet 503 wire

[0088] 600 Data collector 601 Wireless base station 602 Processor 603 Server

[0089] 604 receiver 605 pad 606 smart phone 607 PC 608 display terminal DETAILED DESCRIPTION

[0090] In order to further explain the technical solution of the present invention, it is described in detail below in conjunction with embodiments.

[0091] Reference Figures 1 to 39 The present invention first proposes a self-unlocking anchor for a retrievable anchor rod, specifically referring to Figures 1 to 22, comprising an anchor ring 100, a split anchor 200 for clamping an anchor steel strand, a clip 230 and a T-shaped screw 300. In the embodiment, the anchor steel strand is a steel strand 400, and the anchor ring 100 is sleeved outside the split anchor 200. The anchor ring 100 comprises a first anchor ring 110 and a second anchor ring 120. The first anchor ring 110 comprises an upper end ring 114 and two upper wedge platforms 111 respectively arranged on the upper side of the upper end ring 114. The two upper wedge platforms 111 are each provided with a through long strip unlocking groove 113, which runs from the upper end surface of the upper wedge platform 111 to the lower end surface. The bottom of the upper wedge platform 111 is provided with an inclined upper wedge surface 112. The second anchor ring 120 includes a lower end ring 124 and two lower wedge platforms 121 on the lower side of the lower end ring 124, each of the lower wedge platforms 121 is provided with a through screw hole 123, the screw hole 123 passes through from the upper end surface of the lower wedge platform 121 to the lower end surface, the screw hole 123 corresponds to the position of the unlocking groove 113, and the top of the lower wedge platform 121 is provided with a lower wedge surface 122 that can overlap with the upper wedge surface 112. After the upper wedge surface 112 and the lower wedge surface 122 are fully matched, the first anchor ring 110 and the second anchor ring 120 form an anchor installation groove 130. After the upper wedge platform 111 and the lower wedge platform 121 are assembled, the screw hole 123 cooperates with the bottom of the unlocking groove 113, and the upper wedge platform 111, the upper end ring 114, the lower wedge platform 121 and the lower end ring 124 form an anchor installation groove 130 for accommodating the split anchor 200. The nut part 310 of the T-shaped screw 300 abuts against the top of the upper wedge platform 111, and the screw part 330 of the T-shaped screw 300 is screwed into the screw hole 123 to tighten the upper wedge platform 111 and the lower wedge platform 121 together.

[0092] As a preferred embodiment of the present invention, the cross section of the outer wall of the anchor ring 100 is circular, and the cross section of the anchor installation groove 130 is rectangular.

[0093] As a preferred embodiment of the present invention, the length of the anchor installation groove 130 is equal to the length of the split anchor 200, and the width of the anchor installation groove 130 is equal to the width of the assembled split anchor 200.

[0094] As a preferred embodiment of the present invention, the split anchor 200 includes two identical first split anchors 210 and one second split anchor 220, the second split anchor 220 is arranged between the two first split anchors 210, the first split anchor 210 is provided with a first semi-conical hole 211 and a first semi-rebar hole 212, and the second split anchor 220 is provided with a second semi-conical hole 221 matching the first semi-conical hole 211 and a second semi-rebar hole 222 matching the first semi-rebar hole 212 on both sides, and each of the steel strands is clamped in the first semi-conical hole 211 and the second semi-conical hole 221 by two clips 230. The first semi-conical hole 211 and the second semi-conical hole 221 can be surrounded by a conical hole, and the first semi-rebar hole 212 and the second semi-rebar hole 222 can be surrounded by a rebar hole. The clip 230 is a conventional clip 230 in the field of anchorage, which includes a cone and a wing connecting the upper end of the cone, and the outer diameter of the wing is greater than the maximum outer diameter of the semi-cone. When in use, two or three clips 230 are usually used to clamp a strand 400.

[0095] As a preferred embodiment of the present invention, the length direction of the unlocking groove 113 is along the extension direction of the upper wedge 111. As a preferred embodiment of the present invention, the length direction of the split anchor 200 is parallel to the connecting direction of the left and right unlocking grooves 113. As a preferred embodiment of the present invention, the width of the unlocking groove 113 is 27-38 mm, and the length of the unlocking groove 113 is 54-76 mm.

[0096] As a preferred embodiment of the present invention, the sum of the lengths of the screw portion 320 and the screw portion 330 of the T-shaped screw 300 is the same as the height of the upper end ring 114, and the length of the screw portion 330 is 2 to 6 mm greater than the length of the screw hole 123 of the second anchor ring 120.

[0097] The present invention also proposes a construction method for a self-unlocking anchor for a recyclable anchor rod, comprising the following steps:

[0098] (1) Installation of anchor rings: Place the upper wedge 111 of the first anchor ring 110 on the lower wedge 121 of the second anchor ring 120, and make the upper wedge 111 of the first anchor ring 110 abut against the lower end ring 124 of the second anchor ring 120, and the lower wedge 121 of the second anchor ring 120 abut against the upper end ring 114 of the first anchor ring 110, then insert the T-shaped screw 300 into the bottom of the unlocking groove 113 of the first anchor ring 110, screw it into the screw hole 123 of the second anchor ring 120, and make the nut part 310 of the T-shaped screw 300 press against the top surface of the first anchor ring 110, and complete the installation of the anchor ring 100;

[0099] (2) Installation of the split anchor 200: insert the installed anchor ring 100 onto the steel strand of the anchor rod to be anchored, adjust the position of the anchor ring 100 so that the steel strand is centered, and sequentially place the first split anchor 210 and the second split anchor 220 into the anchor installation groove 130 of the anchor ring 100, with the length direction of the first split anchor 210 and the second split anchor 220 being parallel to the direction of the connecting line of the left and right unlocking grooves 113; place the clip 230 into the first semi-conical hole 211 and the second semi-conical hole 221, and push them until they are tight, thus completing the installation of the split anchor 200;

[0100] (3) Tensioning and locking of the anchor steel strand 400: The anchor steel strand 400 is tensioned to the designed prestress value by a tensioning jack and then locked to complete the anchor construction;

[0101] (4) Removal of the self-unloading anchor: After the anchor support function is used, first insert a steel sheet under the wing plate 232 of all the clips 230 to prevent the clips 230 from further sliding into the tapered hole during the unlocking process; then use a wrench to slowly and symmetrically loosen the two T-shaped screws 300 on the anchor ring 100. Since there is a gap above the unlocking groove 113 where the T-shaped screws 300 are located, at this time, the first split anchor 210, under the squeezing effect of the clip 230 holding the steel strand 400, pushes the first anchor ring 110 at the same time, so that the first anchor ring 110 moves along the lower wedge surface 122, and is released. Zhang clamps the first split anchor 210 and the second split anchor 220. Since there is a steel sheet plugged under the wing plate 232 of the clip 230, the clip 230 cannot be further locked into the tapered hole, so that the first split anchor 210 and the second split anchor 220 are separated; the T-shaped screw 300 is continued to be loosened symmetrically and synchronously, so that the T-shaped screw 300 moves to the top of the unlocking groove 113. At this time, the first split anchor 210 and the second split anchor 220 are fully separated, and the clip 230, the split anchor 200 and the anchor ring 100 are taken out in turn to complete the removal of the anchors.

[0102] Reference Figure 23 to Figure 27 The second embodiment of the present invention proposes a self-unlocking anchor of another structure, which is different from the first embodiment in the structure of the anchor ring and the structure of the split anchor.

[0103] In this embodiment, the cross-section of the anchor installation groove 130 formed by the assembly of the first anchor ring 110 and the second anchor ring 120 is circular, and the cross-section of the split anchor 200 after assembly is circular, and the circular split anchor 200 cooperates with the circular anchor installation groove 130.

[0104] Reference Figures 28 to 36 The third embodiment of the present invention proposes a self-unlocking anchor of another structure, which is different from the first embodiment in the structure of the anchor ring and the structure of the split anchor.

[0105] In this embodiment, the anchor ring includes a first anchor ring 110, a second anchor ring 120 and a connecting piece connecting the first anchor ring 110 and the second anchor ring 120. The first anchor ring 110 and the second anchor ring 120 both include a semicircular locking ring 105 and locking ears 101 arranged at both ends of the locking ring 105. The locking ears 101 are provided with bolt through holes 102. The connecting piece is a bolt 103 and a nut 104. The bolt through holes 102 are arranged in a horizontal direction. After the first anchor ring 110 and the second anchor ring 120 are abutted against each other, the bolt 103 passes through the bolt through hole 102, and then the first anchor ring 110 and the second anchor ring 120 are locked together by the nut 104. The cross section of the anchor installation groove 130 surrounded by the first anchor ring 110 and the second anchor ring 120 is circular.

[0106] In this embodiment, the split anchor 200 includes two identical first split anchors 210 and one second split anchor 220, the second split anchor 220 is arranged between the two first split anchors 210, the first split anchor 210 is provided with a first semi-conical hole 211 and a first semi-rebar hole 212, the second split anchor 220 is provided with a second semi-conical hole 221 matching the first semi-conical hole 211 and a second semi-rebar hole 222 matching the first semi-rebar hole 212 on both sides, the first semi-conical hole 211 and the second semi-conical hole 221 form a conical hole, and each anchor steel strand 400 is installed in the conical hole through two clips 230. The difference from the first embodiment is that the split anchor 200 formed by assembling two first split anchors 210 and one second split anchor 220 has a circular cross-section of the outer wall. In addition, limiting tongues 213 are provided at both ends of the second split anchor 220 , and the limiting tongues 213 just press against the upper end of the anchor ring 100 .

[0107] The present invention also proposes an intelligent anchor, including an anchor ring 100 and a split anchor 200 for clamping an anchor steel strand, wherein the anchor ring 100 includes a first anchor ring 110 and a second anchor ring 120, which are locked together by a connector, and the first anchor ring 110 and the second anchor ring 120 form an anchor installation groove 130 for installing the split anchor 200, and further includes a strain gauge 501 and a data collector 600 for sensing the circumferential strain of the anchor ring 100, wherein the strain gauge 501 is connected to the data collector 600 via a wire 503, and the strain gauge 501 is fixed in the middle of the outer wall of the locking ring 105 of the anchor ring 100 along the circumferential direction of the anchor ring 100. The anchor ring 100 and the split anchor 200 involved in the intelligent anchor in the present invention may adopt the structure described in the second embodiment or the structure described in the third embodiment.

[0108] The present invention may also include a compensation sheet 502, which is axially fixed along the outer wall of the locking ring 105 of the anchor ring 100. The compensation sheet 502 is connected to the data collector 600 via a wire 503. Since the split anchor ring 100 does not produce axial strain, the compensation sheet 502 can be used to balance the strain difference caused by the temperature of the strain gauge 501.

[0109] The strain gauge 501 and the compensation gauge 502 in the present invention can both adopt the common resistive strain gauge 501 on the market, which is fixed to the outer wall of the lock ring 105 of the anchor ring 100 by gluing, and can be further packaged and protected by being wrapped with epoxy resin.

[0110] The invention also proposes a method for testing the axial force of an anchor rod using an intelligent anchor, using the anchors of the second and third embodiments described above, and using the following calculation method:

[0111] (1) Hoop strain of the outer wall of the first anchor ring 110 The calculation formula is:

[0112] Calculation formula

[0113] Where: u ρ - radial displacement of the outer wall of the first anchor ring 110, m;

[0114] r2-outer diameter of the first anchor ring 110, m;

[0115] (2) Calculation formula of the radial displacement of the outer wall of the first anchor ring 110:

[0116]

[0117] Where: E-elastic modulus of the first anchor ring 110, kPa;

[0118] μ-Poisson's ratio of the first anchor ring 110;

[0119] q-confining pressure of the inner wall of anchor ring 100, kPa;

[0120] r1-inner diameter of anchor ring 100, m;

[0121] (3) Obtain the hoop strain of the outer wall of the first anchor ring 110:

[0122]

[0123] (4) Obtain the inner wall confining pressure of the anchor ring 100:

[0124]

[0125] (5) Calculation formula of anchor bolt axial force N:

[0126] Abbreviated as

[0127] Where: β-inclination angle of the cone hole, degree;

[0128] - the hoop strain of the first anchor ring 110 measured by the strain gauge 501;

[0129] h – height of anchor ring 100, m;

[0130] π – pi;

[0131] The k-axis force coefficient is obtained

[0132] α- Anchor ring shape coefficient, default value is 1.0; calibrated before leaving the factory.

[0133] The specific steps are:

[0134] (1) Connect the strain gauge 501 and the compensation gauge 502 on the anchor ring 100 to the data acquisition device 600 using a wire 503;

[0135] (2) Based on the size, elastic modulus, Poisson's ratio of the anchor ring 100 and the cone angle of the cone hole of the split anchor 200, the formula Calculate the axial force coefficient k;

[0136] (3) Input the axial force coefficient k into the information option box of the strain gauge 501 of the data acquisition device 600, and input the anchor ring shape coefficient α into the data acquisition device 600. The data acquisition device 600 automatically calculates the shape coefficient α according to the circumferential strain measured by the strain gauge 501 on the anchor ring 100 according to the formula Calculate and output the anchor axial force.

[0137] Due to the application of the technical solution, compared with the existing anchors, the present invention has the following significant advantages:

[0138] (1) The first anchor ring 110 and the second anchor ring 120 are tightly connected by high-strength bolts, which is convenient for assembly; (2) When the steel strand 400 is locked, the split parts of the split anchor 200 are squeezed and pushed. At this time, the anchor ring 100 can effectively clamp the split anchor 200, and then firmly clamp the steel strand 400; (3) In the anchor rod axial force calculation formula, the strain of the strain gauge 501 can be collected in real time, and the other parameters are all known quantities. The anchor rod axial force coefficient can be calculated in advance based on the known parameters, and the anchor ring shape coefficient can be calibrated and determined before leaving the factory. After the parameters and coefficients are input and stored in the system of the data acquisition device 600, the data acquisition device 600 can automatically calculate the value of the strain gauge 501 according to the test value of the strain gauge 501. The calculation is performed dynamically to output the axial force value of the anchor rod in real time; (4) The split anchor 200, the split anchor ring 100 and the strain gauge 501 attached thereto are used to form an intelligent anchor, which can replace the traditional method of using a dynamometer to test the axial force of the anchor rod; (5) The traditional dynamometer is expensive, with a market price of about 900-3000 yuan per piece, while a single strain gauge 501 is about 0.5-2.0 yuan, and the intelligent anchor can be recycled and reused, which significantly saves the project cost; (6) Since the intelligent anchor can be recycled and reused, the strain gauge 501 is inexpensive, and the axial force of all anchor rods of the anchoring project can be monitored in real time. Once a dangerous situation is found, a timely and accurate warning can be issued to ensure the safety of the project.

[0139] The present invention also proposes an anchor axial force remote monitoring system based on an intelligent anchor, including an intelligent anchor, a processor 602, a server 603 and a receiver 604. The intelligent anchor is communicatively connected to the processor 602, and the processor 602 is communicatively connected to the receiver 604. The intelligent anchor includes an anchor ring 100, a split anchor 200 for clamping an anchor steel strand 400, a strain gauge 501 for sensing the circumferential strain of the anchor ring 100, and a data acquisition device 600 connected to the strain gauge 501. The anchor ring 100 is mounted on the outside of the split anchor 200, and the strain gauge 501 is fixed to the outer wall of the locking ring 105 of the anchor ring 100 along the circumferential direction of the anchor ring 100.

[0140] As a preferred embodiment of the present invention, the processor 602 is connected to the data collector 600 by wireless communication, specifically, the signal is transmitted successively through the wireless base station 601, the processor 602 is connected to the server 603, and the server 603 is connected to the receiver 604 by wireless communication. As a preferred embodiment of the present invention, the receiver 604 is a Pad 605, a smart phone 606, a PC 607, or other display terminals 608. Based on the concept of the present invention of monitoring the anchor by collecting the data of the strain gauge 501, those skilled in the art can select the corresponding data collector 600, the processor 602 and the server 603 to achieve the purpose of the present invention.

[0141] The present invention further proposes a monitoring method, which uses a remote monitoring system for anchor axial force based on an intelligent anchor. The intelligent anchor can use the second and third anchors in the above-mentioned anchors. Taking the intelligent anchor in the third embodiment as an example, the method includes the following steps:

[0142] (1) Intelligent anchor installation

[0143] Installation of anchor ring 100: Paste strain gauge 501 and compensation sheet 502 on the outer wall of locking ring 105 of first anchor ring 110 in the specified direction and seal them, close locking ears 101 of first anchor ring 110 and second anchor ring 120, insert bolt 103 into bolt through hole 102, and lock anchor ring 100 with nut 104 to complete installation of anchor ring 100;

[0144] Assembly of the split anchor 200: insert the assembled anchor ring 100 onto the anchor steel strand 400 to be locked, and press it against the force transmission structure beam or plate, insert the first split anchor 210 and the second split anchor 220 into the anchor steel strand 400, and install the assembled split anchor 200 into the inner hole of the anchor ring 100, hold the split anchor 200 still, rotate the anchor ring 100 until the tangent of the outer wall center vertex of the locking ring 105 is parallel to the long side of the second split anchor 220, stop rotating the anchor ring 100, and then insert the clip 230 into the tapered hole to complete the assembly of the split anchor 200;

[0145] (2) Data signal connection

[0146] The strain gauge 501 and the compensation sheet 502 on the intelligent anchor are connected to the data collector 600 through the wire 503, and then the data collector 600 is connected to the processor 602, and the processor 602 is connected to the server 603, and the corresponding information is sent to the receiver 604 through the server 603;

[0147] (3) Remote monitoring of anchor axial force

[0148] The anchor steel strand 400 is tensioned by a jack and locked according to the designed prestressing. The anchor axial force is collected in real time to the data collector 600 and further transmitted to the receiver 604 in real time. The anchor axial force is continuously monitored until the anchor support function ends.

[0149] The product form of the present invention is not limited to the embodiments of this case. Any appropriate changes or modifications made by anyone with similar ideas should be deemed to be within the patent scope of the present invention.

Claims

1. An intelligent anchor, comprising an anchor ring and a split anchor for clamping an anchor rod steel strand, wherein the anchor ring comprises a first anchor ring and a second anchor ring, the first anchor ring and the second anchor ring are locked together by a connector, and the first anchor ring and the second anchor ring form an anchor installation groove for installing the split anchor, characterized in that: It also includes a strain gauge and a data collector for sensing the hoop strain of the anchor ring, the strain gauge is connected to the data collector via a wire, and the strain gauge is fixed at the center of the outer wall of the lock ring of the anchor ring along the hoop direction of the anchor ring; It also includes a compensation sheet, which is fixed to the outer wall of the lock ring of the anchor ring along the axial direction of the anchor ring, and the compensation sheet is connected to the data collector; The split anchor comprises two identical first split anchors and one second split anchor, the second split anchor is arranged between the two first split anchors, the first split anchor is provided with a first semi-conical hole and a first semi-rebar-piercing hole, both sides of the second split anchor are provided with a second semi-conical hole matching the first semi-conical hole and a second semi-rebar-piercing hole matching the first semi-conical hole, the first semi-conical hole and the second semi-conical hole form a conical hole, and each of the steel strands is installed in the conical hole through two clips; The first anchor ring and the second anchor ring each include a semicircular locking ring and locking ears arranged at both ends of the locking ring, the locking ears are provided with bolt through holes, and the connecting piece is a bolt and a nut; The two ends of the second split anchor are provided with limiting tongues, and the limiting tongues are pressed against the upper end of the anchor ring; The strain gauge and the compensation sheet are fixed to the locking ring of the anchor ring by gluing; The strain gauge is a resistance strain gauge.

2. The method for testing the axial force of anchor rod by intelligent anchor is characterized by: Using the intelligent anchor described in claim 1, the following calculation method is used: (1) Hoop strain of the outer wall of the first anchor ring The calculation formula is: Calculation formula Where: u ρ - radial displacement of the outer wall of the first anchor ring, m; r2-outer diameter of the first anchor ring, m; (2) Calculation formula for the radial displacement of the outer wall of the first anchor ring: Where: E-elastic modulus of the first anchor ring, kPa; μ - Poisson's ratio of the first anchor ring; q-confining pressure of the inner wall of the anchor ring, kPa; r1-inner diameter of anchor ring, m; (3) Obtain the hoop strain of the outer wall of the first anchor ring: (4) Obtain the inner wall confining pressure of the anchor ring: (5) Calculation formula of anchor bolt axial force N: Abbreviated as Where: β-inclination angle of the cone hole, degree; - Hoop strain of the first anchor ring obtained by strain gauge testing; h – height of anchor ring, m; π – pi; The k-axis force coefficient is obtained α- Anchor ring shape coefficient, default value is 1.0; calibrated before leaving the factory.

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