A steel bar meter connection device and installation method

Abstract

The present invention relates to the field of steel bar meters, and discloses a steel bar meter connection device and an installation method, comprising a box body, wherein the box body comprises a first force transmission rod and a first stress-bearing steel bar arranged above the box body, and a second force transmission rod and a second stress-bearing steel bar arranged below the box body; the first force transmission rod is welded to the first stress-bearing steel bar, and the second force transmission rod is welded to the second stress-bearing steel bar; homogeneous steel bars and a steel bar meter are respectively arranged on both sides of the stress-bearing steel bars; the homogeneous steel bars are respectively connected to sleeves at the top and bottom, and the sleeves are connecting parts of the homogeneous steel bars and the box body; the homogeneous steel bars are respectively connected to connecting bolts through sleeves, and are fastened on the outside of the box body through nuts, and the steel bar meter is connected to the connecting bolts and is fastened on the outside of the box body through nuts; the outside of the box body comprises threading holes, the steel bar meter is connected to a data cable, and the data cable passes through the threading holes out of the box body.

Description

Technical Field

[0001] The present invention relates to the field of steel bar gauges, and in particular to a steel bar gauge connection device and an installation method. Background Art

[0002] Steel bar stress is an important parameter for monitoring and testing engineering structures. How to accurately obtain steel bar stress parameters is very important for engineering safety. Using a steel bar meter is an important means of testing steel bar stress and is now widely used in engineering.

[0003] The installation quality of the rebar meter has a great impact on the accuracy of its test data. The traditional installation method of the rebar meter leads to a very low survival rate of the rebar meter, which brings great difficulties to engineering inspection and testing. At present, the installation of the rebar meter generally adopts binding, welding and sleeve connection. Binding is to fix the rebar meter with iron wire or rolled strip. This method is difficult to connect the stressed steel bar with the rebar meter firmly, which often causes the steel bar and the rebar meter to fail to deform and coordinate, resulting in test errors. Welding is to fuse the steel bars together at high temperature. This method can stably connect the steel bars, but the welding process is prone to high temperature, which causes the rebar meter to fail. Although watering and ice compressing are adopted at the construction site, it is difficult to ensure that the welding process is controlled below 60℃. The problems of the first two installation methods are solved by connecting the rebar meter with a sleeve. However, in this method, the rebar meter is directly bent during the steel bar hoisting process, causing its deformation to exceed the range, resulting in a large error in the rebar meter test. Summary of the invention

[0004] In view of this, an embodiment of the present invention provides a rebar meter connection device and installation method, which can be well adapted to various environments and will greatly improve the survival rate of the rebar meter.

[0005] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0006] In a first aspect, an embodiment of the present invention provides a steel bar meter connection device, including a box body, wherein the box body includes a first force transmission rod and a first force-bearing steel bar arranged above the box body, and a second force transmission rod and a second force-bearing steel bar arranged below the box body; the first force transmission rod is welded to the first force-bearing steel bar, and the second force transmission rod is welded to the second force-bearing steel bar;

[0007] Homogeneous steel bars and steel bar counters are respectively arranged on both sides of the stressed steel bars; sleeves are respectively connected to the upper and lower parts of the homogeneous steel bars, and the sleeves are connecting parts between the homogeneous steel bars and the box body;

[0008] The homogeneous steel bars are respectively connected to the connecting bolts through sleeves and are fastened on the outside of the box body through nuts; the steel bar meter is connected to the connecting bolts and is fastened on the outside of the box body through nuts;

[0009] The outer side of the box body comprises a threading hole, the rebar meter is connected with a data line, and the data line passes through the threading hole and out of the box body.

[0010] Preferably, it further comprises an anti-bending rod, which penetrates the box body longitudinally and is fixed to the box body on the outside of the box body by pins.

[0011] Preferably, the box body is composed of a first upper box, a second upper box, a first lower box, and a second lower box, and is provided with corresponding spaces inside for accommodating stressed steel bars, force transmission rods, homogeneous steel bars, steel bar gauges, connecting bolts, and anti-bending rods.

[0012] Preferably, it also includes four holes arranged on the first upper box and the first lower box, and the first upper box and the second lower box are respectively connected by disc bolts, and are fastened to the box body by nuts.

[0013] Preferably, the homogeneous steel bar is made of the same material and has the same diameter as the stressed steel bar, and bears 1 / 2 of the stress of the stressed steel bar.

[0014] Preferably, the homogeneous steel bar has the same length as the steel bar meter, is subjected to the same force as the steel bar meter, and has threaded openings for connecting sleeves at the top and bottom.

[0015] In a second aspect, an embodiment of the present invention further provides a method for installing a steel bar meter connection device, the method comprising:

[0016] Step 1: Cut the stress-bearing steel bars and level the ends;

[0017] Step 2: Weld the force transmission rod to the stress-bearing steel bar, usually by double-sided welding;

[0018] Step 3: Use anti-bending rods to connect the first upper box and the first lower box into a whole, and fix them with pins;

[0019] Step 4: Place the steel bar meter and the homogeneous steel bar connecting sleeve into the box respectively;

[0020] Step 5: buckle the force transmission rod into the box, adjust the positions of the steel bar meter and the homogeneous steel bar, confirm that the force transmission rod is parallel to the stressed steel bar, and fasten the box, the steel bar meter and the homogeneous steel bar with connecting bolts;

[0021] Step 6: Install the second upper box and the second lower box, connect the boxes into a whole with disc bolts, and tighten the nuts to secure the boxes;

[0022] Step 7: After the steel cage is hoisted, pull out the pins and the anti-bending rods to separate the first upper box from the first lower box, and the second upper box from the second lower box, and only connect the stress-bearing steel bars through homogeneous steel bars and steel bar gauges.

[0023] The embodiment of the present invention provides a rebar meter connection device and installation method, including a box body, wherein the box body includes a first force transmission rod and a first stress-bearing steel bar arranged above the box body, and a second force transmission rod and a second stress-bearing steel bar below the box body; the first force transmission rod is welded to the first stress-bearing steel bar, and the second force transmission rod is welded to the second stress-bearing steel bar; homogeneous steel bars and a rebar meter are respectively arranged on both sides of the stress-bearing steel bars; the homogeneous steel bars are respectively connected to sleeves above and below, and the sleeves are connecting parts between the homogeneous steel bars and the box body; the homogeneous steel bars are respectively connected to connecting bolts through sleeves, and are fastened on the outside of the box body through nuts, and the rebar meter is connected to the connecting bolts and is fastened on the outside of the box body through nuts; the outside of the box body includes threading holes, and the rebar meter is connected to a data cable, and the data cable passes through the threading holes out of the box body, thus solving the problem of failure of the rebar meter caused by high temperature of welding, hoisting deformation and construction collision during installation of the rebar meter in the past, and the device can be well applied to various environments, which will greatly improve the survival rate of the rebar meter. The present invention can improve the survival of the steel bar meter, ensure the test accuracy of the steel bar meter, effectively improve the success of the steel bar stress test process, and has good economic benefits. In addition, the device has a simple structure, easy operation, high reliability, and can be fully promoted and applied. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural schematic diagram of a steel bar meter connection device in one embodiment of the present invention;

[0025] Figure 2 It is a structural schematic diagram of another steel bar meter connection device in one embodiment of the present invention;

[0026] Figure 3 This is a schematic structural diagram of a box body according to an embodiment of the present invention;

[0027] Figure 4 A 35# pile shaft axial force distribution diagram provided in one embodiment of the present invention;

[0028] Figure 5 A distribution diagram of the side friction resistance of a 35# pile provided in one embodiment of the present invention;

[0029] Figure 6 A 50# pile axial force distribution diagram provided in one embodiment of the present invention;

[0030] Figure 7 A distribution diagram of the side friction of a 50# pile provided in one embodiment of the present invention;

[0031] Figure 8 A 52# pile shaft axial force distribution diagram provided in one embodiment of the present invention;

[0032] Fig. 9A distribution diagram of the side friction resistance of a 52# pile provided in one embodiment of the present invention;

[0033] Among them, the box body 1, the first force transmission rod 2, the first force-bearing steel bar 3, the second force transmission rod 4, the second force-bearing steel bar 5, the homogeneous steel bar 6, the steel bar gauge 7, the sleeve 8, the connecting bolt 9, the nut 10, the threading hole 11, the data cable 12, the anti-bending rod 13, the pin 14, the first upper box 15, the second upper box 16, the first lower box 17, the second lower box 18, and the disc bolt 19. DETAILED DESCRIPTION

[0034] See also Figure 1 to Figure 2 The embodiment of the present invention provides a steel bar meter connection device, comprising a box body 1, wherein the box body 1 comprises a first force transmission rod 2 and a first force-bearing steel bar 3 arranged above the box body 1, and a second force transmission rod 4 and a second force-bearing steel bar 5 arranged below the box body 1; the first force transmission rod 2 is welded to the first force-bearing steel bar 3, and the second force transmission rod 4 is welded to the second force-bearing steel bar 5;

[0035] Homogeneous steel bars 6 and steel bar counters 7 are respectively arranged on both sides of the stressed steel bars; sleeves 8 are respectively connected to the upper and lower parts of the homogeneous steel bars 6, and the sleeves 8 are connecting parts between the homogeneous steel bars 6 and the box body 1;

[0036] The homogeneous steel bars 6 are connected to the connecting bolts 9 through sleeves 8 and are fastened to the outside of the box body 1 through nuts 10. The steel bar meter 7 is connected to the connecting bolts 9 and is fastened to the outside of the box body 1 through nuts 10.

[0037] The outer side of the box body 1 includes a threading hole 11 , and the rebar meter 7 is connected to a data line 12 , and the data line 12 passes through the threading hole 11 and goes out of the box body 1 .

[0038] Here, the rebar gauge 7 itself has pre-made threads on the top and bottom, which are used to connect the upper and lower connecting bolts 9, which are similar in form to the sleeve 8.

[0039] Here, the force transmission rod is connected with the stress-bearing steel bar by welding, and transmits the force to the box body 1.

[0040] Here, the sleeve 8 is a connecting component between the homogeneous steel bar 6 and the box body 1 , and has a threaded opening inside, which can transfer the force of the box body 1 to the homogeneous steel bar 6 .

[0041] In one embodiment, it further includes an anti-bending rod 13 , which longitudinally penetrates the box body 1 and is fixed to the box body 1 at the outside of the box body 1 by a pin 14 .

[0042] Here, the anti-bending rod 13 is a temporary rod connecting the upper and lower parts of the box body 1. Generally, four rods are provided and fixed to the outer shell by pins 14. The main function is to resist the bending moment of the steel bars during the steel bar lifting process and prevent the steel bar gauge 7 from being deformed too much and damaged.

[0043] In one embodiment, see 2 to Figure 3 The box body 1 is composed of a first upper box 15, a second upper box 17, a first lower box 16, and a second lower box 18, and is provided with corresponding spaces for accommodating stressed steel bars, force transmission rods, homogeneous steel bars 6, steel bar gauges 7, connecting bolts 9, and anti-bending rods 13.

[0044] In one embodiment, it also includes four holes set on the first upper box 15 and the first lower box 16, and the first upper box 15 and the second upper box 17, and the first lower box 16 and the second lower box 18 are respectively connected by disc bolts 19, and are fastened to the box body 1 by nuts corresponding to the disc bolts 19.

[0045] In one embodiment, the homogeneous steel bar 6 is made of the same material and has the same diameter as the stressed steel bar, and bears half the force of the stressed steel bar.

[0046] In one embodiment, the homogeneous steel bar 6 is equal in length to the steel bar meter 7, is subjected to the same force as the steel bar meter 7, and has threaded openings for connecting sleeves 8 at the top and bottom.

[0047] An embodiment of the present invention also provides a method for installing a steel bar meter connection device, the method comprising:

[0048] Step 1: Cut the stress-bearing steel bars and level the ends;

[0049] Step 2: Weld the force transmission rod to the stress-bearing steel bar, usually by double-sided welding;

[0050] Step 3: Use the anti-bending rod 13 to connect the first upper box 15 and the first lower box 16 into a whole, and fix them with the pin 14;

[0051] Step 4: Place the steel bar meter 7, the connecting sleeve 8 of the homogeneous steel bar 6 into the box 1 respectively;

[0052] Step 5: buckle the force transmission rod into the box 1, adjust the positions of the steel bar meter 7 and the homogeneous steel bar 6, confirm that the force transmission rod is parallel to the stress-bearing steel bar, and fasten the box 1, the steel bar meter 7, and the homogeneous steel bar 6 by connecting bolts 9;

[0053] Step 6: Install the second upper box 17 and the second lower box 18, connect the box body 1 into a whole through the disc bolts 19, and tighten the nuts to fix the box body 1;

[0054] Step 7: After the steel cage is hoisted, pull out the pin 14, pull out the anti-bending rod 13, separate the first upper box 15 from the first lower box 16, and the second upper box 17 from the second lower box 18, and only connect the stressed steel bars through the homogeneous steel bars 6 and the steel bar gauge 7.

[0055] The present invention will be further described below by means of specific examples.

[0056] Taking the XXX Square Renovation Project of XXX Planning and Design Institute as an example, the site survey unit, engineering geological conditions and information sources are shown in Table 1 below.

[0057] Table 1 Survey units, engineering geological conditions and information sources

[0058]

[0059] For this static load test, the details of the test piles are shown in Table 2 below.

[0060] Table 2 Static load test pile data

[0061]

[0062] The specific data of the steel bar meter position are shown in Table 3.

[0063] Table 3 Rebar meter location data

[0064]

[0065] The specific burial of the test equipment and rebar gauges are as follows: 1) Rebar gauges are laid out every 1m along the pile body, and two rebar gauges are set up in each section (basically arranged symmetrically at 180°);

[0066] 2) Here, the steel bar gauge uses a JTM-V1000 vibrating wire steel bar stress gauge, which is fixed to the main reinforcement of the steel cage by welding and parallel to the longitudinal axis of the pile body;

[0067] 3) The cable connected to the steel bar stress gauge is protected by flexible material and tied inside the steel cage.

[0068] Lead to the ground;

[0069] 4) All steel bar stress gauges are clearly marked and numbered;

[0070] 5) Instruments and equipment: The testing instruments and equipment are composed of JTM-V1000 vibrating wire steel stress meter, JTM-V10B frequency reader, junction box, etc.

[0071] The test principle is as follows: 1) Assumptions: the deformation of the steel bar and concrete of the same section is coordinated; the elastic modulus of the concrete under the pile top is the same; the axial force on the J1 section located 1.0m below the pile top surface is the same as the loading amount of the static load test;

[0072] 2) Elastic modulus of concrete within the pile body Determination: Take the J1 section as the calibration section (i=1), measure the frequency change value of the steel bar stress gauge under the j-level load including preload, and use this to calculate the steel bar strain under each load level Since it is assumed that concrete and steel bars are subjected to force in coordination and no cracks occur, the concrete strain , the stress area of ​​the steel bar at the test box is twice that of the steel bar, so the concrete strain , from which the elastic modulus of the pile concrete under load level j can be calculated . Using steel bars to test strain Elastic modulus of pile concrete The two sets of data can be fitted to the correlation between the two, according to the steel bar strain of the other sections under each load level , and then through the correlation relationship, we can get the load level of each section ;

[0073] For the The cross section in The elastic modulus of concrete in the pile under the action of graded load, and Respectively The cross section in The strains of concrete and steel bars in the pile under the action of graded load.

[0074] 3) Axial force of a certain section of pile The calculation formula is:

[0075] (1)

[0076] Where:

[0077] For a certain cross-section of the pile Axial force at level load;

[0078] , is the elastic modulus of concrete and steel bars in the pile ( Take 3.0×10 7 kPa, Take 2.0×10 8 kPa);

[0079] , It is the total area of ​​concrete and steel bars at the same cross section;

[0080] , is the strain of concrete and steel bars at the same section.

[0081] 4) Calculation formula of the stress on the steel bar stress gauge:

[0082] (2)

[0083] (3)

[0084] Where:

[0085] is the axial force on the steel bar at the i-th measuring section under the j-level load (kN);

[0086] is the measured frequency value of the reinforcement meter at the i-th measuring section under the j-level load (Hz);

[0087] is the initial frequency value of the steel bar stress gauge at section i (Hz);

[0088] k is the stress gauge calibration factor;

[0089] is the stress gauge area of ​​the i-th measuring section (cm 2 ).

[0090] 5) Axial force of pile body at the i-th measuring section under the j-th load:

[0091] (4)

[0092] (5)

[0093] is the area of ​​concrete at the measuring section i;

[0094] is the number of steel bars at the measuring section i;

[0095] is the diameter of the pile at the i measuring section;

[0096] 6) Calculation of pile side friction :

[0097] (6)

[0098] Where:

[0099] is the pile side friction between sections i and i+1 at the jth load level (kPa);

[0100] , are the axial forces (kN) of sections i and i+1 under load level j;

[0101] is the pile side area between section i and section i+1 (m 2 ).

[0102] Test steps:

[0103] 1) Pre-embed the vibrating wire steel stress gauge in the designated position of the test pile body according to the product use requirements;

[0104] 2) The vibrating-wire steel stress gauge should be placed at the interface of two soil layers of different properties to measure the stratified friction resistance of the pile in different soil layers. A measuring section should be set at (or above) the ground as the calibration section of the steel stress gauge sensor. The distance between the buried section of the steel stress gauge and the top and bottom of the pile should not be less than 1 times the pile diameter. Two steel stress gauges should be set symmetrically at the same section. The steel gauge should be selected according to the diameter of the main reinforcement. The measurable frequency range of the instrument should be greater than 1.2 times the frequency of the pile at maximum load;

[0105] 3) Before use, the rebar meter should be calibrated one by one to obtain the relationship between pressure (tension) and frequency. The vibrating wire rebar meter is measured by a matching frequency meter, and the resolution of the frequency meter should be better than or equal to 1Hz;

[0106] 4) Conduct internal force test on pile body during load test. For summary of test results, see Figures 4 to 9 And as shown in Tables 4 to 9 below.

[0107] Table 4 35# pile axial force data table (kN)

[0108]

[0109] Table 5 35# pile side wall friction data table (kPa)

[0110]

[0111] Table 6 50# pile axial force data table (kN)

[0112]

[0113] Table 7 50# pile side wall friction data table (kPa)

[0114]

[0115] Table 8 52# pile axial force data table (kN)

[0116]

[0117] Table 9 52# pile side wall friction data table (kPa)

[0118]

[0119] In the specific embodiment of the present invention, the internal force test of the pile body of three pull-out piles was carried out, and the axial force of the detection section of each test pile body was obtained, and the friction resistance of the soil on the pile side was calculated as shown in Table 10:

[0120] Table 10 Friction data of soil on the pile side

[0121]

[0122] The embodiment of the present invention provides a rebar meter connection device and installation method, including a box body, wherein the box body includes a first force transmission rod and a first stress-bearing steel bar arranged above the box body, and a second force transmission rod and a second stress-bearing steel bar below the box body; the first force transmission rod is welded to the first stress-bearing steel bar, and the second force transmission rod is welded to the second stress-bearing steel bar; homogeneous steel bars and a rebar meter are respectively arranged on both sides of the stress-bearing steel bars; the homogeneous steel bars are respectively connected to sleeves above and below, and the sleeves are connecting parts between the homogeneous steel bars and the box body; the homogeneous steel bars are respectively connected to connecting bolts through sleeves, and are fastened on the outside of the box body through nuts, and the rebar meter is connected to the connecting bolts and is fastened on the outside of the box body through nuts; the outside of the box body includes threading holes, and the rebar meter is connected to a data cable, and the data cable passes through the threading holes out of the box body, thus solving the problem of failure of the rebar meter caused by high temperature of welding, hoisting deformation and construction collision during installation of the rebar meter in the past, and the device can be well applied to various environments, which will greatly improve the survival rate of the rebar meter. The present invention can improve the survival of the steel bar meter, ensure the test accuracy of the steel bar meter, effectively improve the success of the steel bar stress test process, and has good economic benefits. In addition, the device has a simple structure, easy operation, high reliability, and can be fully promoted and applied.

[0123] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement and improvement made within the spirit and scope of the present invention are included in the protection scope of the present invention.

Claims

1. A steel bar meter connection device, It is characterized in that The box body comprises a first upper box, a second upper box, a first lower box, and a second lower box, and is provided with corresponding spaces for accommodating stress-bearing steel bars, force transmission rods, homogeneous steel bars, a steel bar meter, connecting bolts, and bending-resistant rods; the box body comprises a first force transmission rod and a first stress-bearing steel bar arranged above the box body, and a second force transmission rod and a second stress-bearing steel bar arranged below the box body; the first force transmission rod is welded to the first stress-bearing steel bar, and the second force transmission rod is welded to the second stress-bearing steel bar; Homogeneous steel bars and steel bar counters are respectively arranged on both sides of the stressed steel bars; sleeves are respectively connected to the upper and lower parts of the homogeneous steel bars, and the sleeves are connecting parts between the homogeneous steel bars and the box body; The homogeneous steel bars are respectively connected to the connecting bolts through sleeves and are fastened on the outside of the box through corresponding nuts; the steel bar meter is connected to the connecting bolts and is fastened on the outside of the box through corresponding nuts; The outer side of the box body comprises a threading hole, the rebar meter is connected with a data line, and the data line passes through the threading hole and out of the box body.

2. The steel bar meter connection device according to claim 1, It is characterized in that It also includes an anti-bending rod, which penetrates the box body longitudinally and is fixed to the box body at the outside of the box body through pins.

3. The steel bar meter connection device according to claim 1, It is characterized in that It also includes four holes arranged on the first upper box and the first lower box, through which the first upper box and the second upper box, and the first lower box and the second lower box are respectively connected by disc bolts, and are fastened to the box body by corresponding nuts.

4. The steel bar meter connection device according to claim 1, It is characterized in that The homogeneous steel bar is made of the same material and has the same diameter as the stressed steel bar, and bears 1 / 2 of the stress of the stressed steel bar.

5. The steel bar meter connection device according to claim 1, It is characterized in that The length of the homogeneous steel bar is equal to that of the steel bar meter, the force it bears is equal to that of the steel bar meter, and there are threaded openings for connecting sleeves at the top and bottom.

6. A method for installing a steel bar meter connection device according to any one of claims 1 to 5, It is characterized in that The method comprises: Step 1: Cut the stressed steel bars and level the ends; Step 2: Weld the force transmission rod to the stress-bearing steel bar using double-sided welding; Step 3: Use the anti-bending rod to connect the first upper box and the first lower box into a whole, and fix them with pins; wherein the box body is composed of the first upper box, the second upper box, the first lower box, and the second lower box, and is provided with corresponding spaces for accommodating the stressed steel bars, the force transmission rods, the homogeneous steel bars, the steel bar meter, the connecting bolts, and the anti-bending rods; Step 4: Place the steel bar meter and the homogeneous steel bar connecting sleeve into the box respectively; Step 5: buckle the force transmission rod into the box, adjust the positions of the steel bar meter and the homogeneous steel bar, confirm that the force transmission rod is parallel to the stressed steel bar, and fasten the box, the steel bar meter and the homogeneous steel bar with connecting bolts; Step 6: Install the second upper box and the second lower box, connect the boxes into a whole with disc bolts, and tighten the corresponding nuts to secure the boxes; Step 7: After the steel cage is hoisted, pull out the pins and the anti-bending rods to separate the first upper box from the first lower box, and the second upper box from the second lower box, and only connect the stress-bearing steel bars through homogeneous steel bars and steel bar gauges.

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