A falling block system convenient for measuring bearing pressure and a bearing pressure calculation method

Abstract

The present invention provides a formwork removal block system facilitating bearing pressure measurement and a bearing pressure calculation method. The system includes: a formwork removal block body which comprises two top blocks arranged vertically, and two adjusting blocks are provided between the two top blocks. The cross-sections of the top blocks and the adjusting blocks are both trapezoidal, and the two adjusting blocks are fixedly connected by a screw rod; a measuring mechanism which includes a measuring device located on one or more of the top block, the adjusting block, and the screw rod, and the measuring device is electrically connected to a computer. The steps of the calculation method are as follows: calculating the strain ε of the screw rod; calculating the axial stress σ of the screw rod; calculating the axial force N of the screw rod; calculating the bearing pressure F of the formwork removal block. The structure of the present invention is simple, convenient for loading and unloading, reusable, and resource-saving; the method of the present invention is easy to implement, convenient to operate, can monitor the real-time bearing state of the formwork removal block to ensure that the pressure received by the formwork removal block is always within its bearing capacity range, and reduces potential safety hazards.

Description

Technical Field

[0001] The present invention relates to the technical field of drop blocks, and particularly to a drop block system for facilitating the measurement of bearing pressure and a method for calculating bearing pressure. Background Art

[0002] The dropping device is an indispensable part of the cast-in-situ support of reinforced concrete bridges. Steel wedge blocks or sand cylinders are often used as the dropping devices of cast-in-situ supports, but in the use process, steel wedge blocks or sand cylinders often encounter the phenomena of inconvenient installation and disassembly and poor dropping effect.

[0003] In the prior art, the utility model patent with the publication number CN206189273U discloses a support drop block, which has a simple structure and is convenient for installation and disassembly. By loosening the nut of the tension rod, the upper part of the upper support can fall before the upper support is removed. As the most important component of the drop block, the axial force of the tension rod is an important index for evaluating whether the working state of the drop block is safe. The existing drop blocks do not monitor the axial force in real time, and there are great potential safety hazards. Summary of the Invention

[0004] The present invention aims to solve the deficiencies of the prior art, and provides a drop block system for facilitating the measurement of bearing pressure and a method for calculating bearing pressure.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A drop block system for facilitating the measurement of bearing pressure, comprising:

[0007] A drop block body, which includes two top blocks arranged up and down. There are two adjusting blocks between the two top blocks. The cross-sections of the top blocks and the adjusting blocks are both trapezoidal. The two adjusting blocks are fixedly connected by a screw.

[0008] A measuring mechanism, which includes a measuring device. The measuring device is located on one or more of the top block, the adjusting block, and the screw. The measuring device is electrically connected to a computer.

[0009] Further, the measuring device is connected to the computer through a radio communication module.

[0010] Further, the measuring device is a digital display micrometer.

[0011] Further, the digital display micrometer is provided with a magnetic suction base. The digital display micrometer is adsorbed on the inner side of the top block and / or the adjusting block, and the end of the measuring needle contacts the adjacent adjusting block and / or top block.

[0012] Further, the radio communication module includes a Bluetooth receiver matching the digital display micrometer. The Bluetooth receiver is connected to the computer through a USB interface.

[0013] Further, the measuring device is a vibrating wire strain gauge, and the vibrating wire strain gauge is arranged along the screw.

[0014] Further, the radio communication module includes a multi-channel vibrating wire collector, and the output end of the multi-channel vibrating wire collector is connected to a computer through a group of radio data transmitters.

[0015] Further, several nuts and gaskets for limiting the adjusting block are provided at the end of the screw.

[0016] A method for calculating the bearing pressure of the dropping block based on a digital display micrometer, the specific steps are as follows:

[0017] Step 1, calculate the screw strain ε according to the elongation ΔL of the screw collected by the digital display micrometer and the effective length of the screw.

[0018] Step 2, calculate the axial stress σ of the screw according to the elastic modulus E of the screw and the screw strain ε obtained in Step 1.

[0019] Step 3, calculate the axial force N of the screw according to the axial stress σ of the screw obtained in Step 2 and the effective cross-sectional area A of the screw.

[0020] Step 4, calculate the bearing pressure F of the dropping block according to the axial force N of the screw obtained in Step 3 and the slope ratio 1 / n of the dropping block.

[0021] A method for calculating the bearing pressure of the dropping block based on a vibrating wire stress gauge, the specific steps are as follows:

[0022] Step a, calculate the axial stress σ of the screw according to the screw strain ε collected by the vibrating wire stress gauge and the elastic modulus E of the screw.

[0023] Step b, calculate the axial force N of the screw according to the axial stress σ of the screw obtained in Step a and the effective cross-sectional area A of the screw.

[0024] Step c, calculate the bearing pressure F of the dropping block according to the axial force N of the screw obtained in Step b and the slope ratio 1 / n of the dropping block.

[0025] The beneficial effects of the present invention are as follows: The structure of the present invention is simple, convenient for loading and unloading, reusable, and resource-saving; the method of the present invention is easy to implement, convenient to operate, can monitor the real-time bearing state of the dropping block to ensure that the pressure received by the dropping block is always within its bearing capacity range, and reduces potential safety hazards. Description of the Drawings

[0026] Figure 1 It is a schematic structural diagram of the present invention when a digital display micrometer is used;

[0027] Figure 2 It is a schematic structural diagram of the present invention when a vibrating wire strain gauge is used;

[0028] In the figure: 1 - the main body of the dropping block; 11 - the top block; 12 - the adjusting block; 13 - the screw; 2 - the measuring mechanism; 21 - the measuring device; 22 - the computer; 23 - the radio communication module;

[0029] The following will be described in detail with reference to the embodiments of the present invention and the accompanying drawings. Specific embodiments

[0030] The present invention will be further described below in conjunction with the embodiments:

[0031] As shown in the figure, this embodiment includes:

[0032] The main body of the dropping block 1, the main body of the dropping block 1 includes two top blocks 11 arranged up and down, two adjusting blocks 12 are provided between the two top blocks 11, the cross-sections of the top blocks 11 and the adjusting blocks 12 are both trapezoidal and the short sides of the trapezoids are both on the side close to each other, the hypotenuse of the trapezoid is in sliding fit with the hypotenuse of the adjacent top block 11 or adjusting block 12, the two adjusting blocks 12 are fixedly connected by a screw 13, and the end of the screw 13 is provided with a number of nuts and gaskets for limiting the adjusting block 12;

[0033] The measuring mechanism 2, the measuring mechanism 2 includes a measuring device 21, the measuring device 21 is electrically connected to the computer 22 through the radio communication module 23. Among them, the measuring device 21 can either adopt a digital display micrometer or a vibrating wire strain gauge.

[0034] When using a digital display micrometer, a magnetic base is set at its bottom to facilitate its adsorption to the inner side of the top block 11, the end of its measuring needle contacts the short side of the adjacent adjusting block 12. At the same time, the digital display micrometer can also be set on the adjusting block 12 and its measuring needle end contacts the adjacent top block 11; the number of digital display micrometers can also be multiple and the average value of the measurement results is used as the basis for calculation to improve the accuracy of the measurement results; the radio communication module 23 includes a Bluetooth receiver matching the digital display micrometer, and the Bluetooth receiver is connected to the computer 22 through a USB interface. The specific steps of the bearing pressure calculation method are as follows:

[0035] Step 1, calculate the strain ε of the screw 13 according to the elongation ΔL of the screw 13 collected by the digital display micrometer and the effective length of the screw, and the calculation formula is: ε = ΔL / L;

[0036] Step 2, calculate the axial stress σ of the screw 13 according to the elastic modulus E of the screw 13 and the strain ε of the screw 13 obtained in Step 1, and the calculation formula is: σ = Eε;

[0037] Step 3, calculate the axial force N of the screw 13 according to the axial stress σ of the screw 13 obtained in Step 2 and the effective cross-sectional area A of the screw 13, and the calculation formula is: N = σA;

[0038] Step 4: Calculate the bearing pressure F of the unloading block according to the axial force N of the screw 13 obtained in Step 3 and the slope ratio 1 / n of the unloading block. The calculation formula is: F = nN.

[0039] When a vibrating wire strain gauge is adopted, the vibrating wire strain gauge is arranged along the screw 13. The radio communication module 23 includes a multi-channel vibrating wire collector. The output end of the multi-channel vibrating wire collector is connected to the computer 22 through a group of wireless data transmission stations. At this time, the specific steps of the bearing pressure calculation method are as follows:

[0040] Step a: Calculate the axial stress σ of the screw 13 according to the strain ε of the screw 13 collected by the vibrating wire stress gauge and the elastic modulus E of the screw 13. The calculation formula is: σ = Eε;

[0041] Step b: Calculate the axial force N of the screw 13 according to the axial stress σ of the screw 13 obtained in Step a and the effective cross-sectional area A of the screw 13. The calculation formula is: N = σA;

[0042] Step c: Calculate the bearing pressure F of the unloading block according to the axial force N of the screw 13 obtained in Step b and the slope ratio 1 / n of the unloading block. The calculation formula is: F = nN.

[0043] During use, integrate the above calculation method into the software of the computer, and use the display of the computer to display the specific value of the bearing pressure in real time. The rated bearing pressure of each unloading block can also be preset in the software. When the actual bearing pressure is close to or higher than the rated value, an alarm is given to give a timely reminder to the monitor, which can further reduce potential safety hazards.

[0044] The present invention has been described exemplarily in combination with specific embodiments. Obviously, the specific implementation of the present invention is not limited by the above methods. As long as various improvements are made by adopting the method concept and technical solution of the present invention, or directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A falling block system convenient for measuring bearing pressure, characterized in that, Comprising: A falling block body (1), the falling block body (1) includes two top blocks (11) arranged up and down, there are two adjusting blocks (12) between the two top blocks (11), the cross-sections of the top blocks (11) and the adjusting blocks (12) are both trapezoidal, and the two adjusting blocks (12) are fixedly connected by a screw (13); A measuring mechanism (2), the measuring mechanism (2) includes a measuring device (21), the measuring device (21) is located on multiple of the top block (11), the adjusting block (12), and the screw (13), and the measuring device (21) is electrically connected to a computer (22); The measuring device (21) is connected to the computer (22) through a radio communication module (23); The measuring device (21) is a digital display micrometer, the digital display micrometer is provided with a magnetic suction base, the digital display micrometer is adsorbed on the inner side of the top block (11) and / or the adjusting block (12), and the end of the measuring needle contacts the adjacent adjusting block (12) and / or top block (11); The measuring device (21) is a vibrating wire strain gauge, and the vibrating wire strain gauge is arranged along the screw (13).

2. The formwork removal block system for facilitating the measurement of bearing pressure according to claim 1, wherein The radio communication module (23) includes a Bluetooth receiver matching the digital display micrometer, and the Bluetooth receiver is connected to the computer (22) through a USB interface.

3. The load-unloading block system for facilitating the measurement of bearing pressure according to claim 1, wherein, The radio communication module (23) includes a multi-channel vibrating wire collector, and the output end of the multi-channel vibrating wire collector is connected to the computer (22) through a group of wireless data transmission stations.

4. The formwork removal block system for facilitating the measurement of bearing pressure according to claim 1, wherein, The end of the screw (13) is provided with several nuts and gaskets for limiting the adjusting block (12).

5. A calculation method for the bearing pressure of a drop block based on a digital micrometer, which uses the drop block system for facilitating the measurement of the bearing pressure as described in any one of claims 1 to 4, and is characterized in that, The specific steps are as follows: Step 1, calculate the strain ε of the screw (13) according to the elongation ΔL of the screw (13) collected by the digital display micrometer and the effective length of the screw; Step 2, calculate the axial stress σ of the screw (13) according to the elastic modulus E of the screw (13) and the strain ε of the screw (13) obtained in Step 1; Step 3, calculate the axial force N of the screw (13) according to the axial stress σ of the screw (13) obtained in Step 2 and the effective cross-sectional area A of the screw (13); Step 4, calculate the bearing pressure F of the falling block according to the axial force N of the screw (13) obtained in Step 3 and the slope ratio 1 / n of the falling block.

6. A calculation method for the bearing pressure of a drop block based on a vibrating wire type stress gauge, which uses the drop block system for facilitating the measurement of the bearing pressure as described in any one of claims 1 to 4, and is characterized in that The specific steps are as follows: Step a, calculate the axial stress σ of the screw (13) according to the strain ε of the screw (13) collected by the vibrating wire stress gauge and the elastic modulus E of the screw (13); Step b, calculate the axial force N of the screw (13) according to the axial stress σ of the screw (13) obtained in Step a and the effective cross-sectional area A of the screw (13); Step c, calculate the bearing pressure F of the falling block according to the axial force N of the screw (13) obtained in Step b and the slope ratio 1 / n of the falling block.

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