Device and method for testing temperature conduction and frost heave strain of concrete lined channels

Abstract

The present invention discloses a device and method for testing temperature conduction and frost heave strain of a concrete lined channel, the device comprising: a frost heave device, the frost heave device comprising a lined channel body and a temperature control device, the temperature control device being used to provide a predetermined temperature for the lined channel body; a detection device, the detection device comprising a lateral deformation detection device, a vertical deformation detection device and a plurality of temperature sensors; the lateral deformation detection device being used to detect the lateral frost heave strain parameters of the lined channel body; a plurality of temperature sensors being arranged along the axial direction of the lined channel body and embedded in the interior of the lined channel body, being used to detect the temperature conduction performance of the lined channel body. The present invention can achieve the technical effect of quantitatively analyzing the internal temperature conduction process of the lined channel body and measuring the concrete lining plate and the channel foundation soil as a whole.

Description

Technical Field

[0001] The invention relates to the technical field of low temperature testing of materials, and more specifically to a device and method for testing temperature conduction and frost heave strain of a concrete lined channel. Background Art

[0002] The Hetao region of Inner Mongolia is located in the extremely cold area in northern my country, with the lowest temperature in winter reaching -25℃. The channels in the Hetao region are widely distributed, playing an important role in the irrigation of crops and water transport. The lower ambient temperature in the extremely cold area causes a temperature difference between the lining concrete and the channel base soil, causing the heat loss of the base soil. Under low temperature conditions, the channel base soil freezes and forms a frozen soil layer. The increase in soil volume produces frost heave force on the lining, which lifts or cracks the lining, causing frost heave damage to the lining channel. Therefore, the temperature conductivity of the lining channel body has a significant impact on its frost heave situation. However, the field working environment is harsh, the data collection efficiency is low and the instrument is easily damaged, and the testing difficulty and cost are high. Based on this, it is necessary to develop a device that can not only effectively simulate the real environment, but also conduct a joint test of the temperature conductivity and frost heave strain of the lining channel body for auxiliary research.

[0003] The traditional test device for concrete temperature conductivity can only use the surface temperature gradient of the concrete specimen as the measurement parameter, and cannot quantitatively analyze the internal temperature conduction process of the lining channel body. In addition, the test environment required for the test is relatively high, and the environmental parameters cannot be flexibly adjusted. It is impossible to effectively simulate the actual engineering environment and is difficult to apply to the lining engineering field. In addition, the existing frost heave strain measurement technology in the lining engineering field lacks quantitative analysis of the internal temperature conduction process of the lining channel body, and most of them only measure the vertical frost heave of the lining channel body, without considering the lateral frost heave strain. Therefore, the existing technology in this field still has room for improvement.

[0004] Therefore, how to provide a device and method for testing the temperature conduction and frost heave strain of concrete lined channels that can quantitatively analyze the internal temperature conduction process of the lined channel body and measure the entire lined channel body is one of the technical problems that urgently need to be solved in this field. Summary of the invention

[0005] In view of this, the present invention provides a device and method for testing temperature conduction and frost heave strain of a concrete lined channel, which is provided for the purpose of solving the above-mentioned deficiencies.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] A device for testing temperature conduction and frost heave strain of a concrete lined channel, comprising: a frost heave device, the frost heave device comprising a lined channel body and a temperature control device, the temperature control device being used to provide a predetermined temperature for the lined channel body; a detection device, the detection device comprising a lateral deformation detection device, a vertical displacement detection device and a plurality of temperature sensors; the lateral deformation detection device being used to detect the lateral frost heave strain parameters of the lined channel body at the predetermined temperature; the vertical displacement detection device being used to detect the vertical frost heave strain parameters of the lined channel body at the predetermined temperature; a plurality of the temperature sensors being arranged along the axial direction of the lined channel body and embedded in the interior of the lined channel body, for detecting the temperature conduction performance of the lined channel body at the predetermined temperature.

[0008] Preferably, the temperature control device is a refrigeration box; there are two temperature control devices, namely an upper temperature variable box and a lower temperature variable box, and the upper temperature variable box and the lower temperature variable box are tightly fixed to the upper and lower ends of the lined channel body respectively.

[0009] Preferably, a displacement constraint device is connected between the upper temperature change box and the lower temperature change box; the displacement constraint device includes: a first connecting rod, a second connecting rod and a sliding rod; the first end of the first connecting rod is fixedly connected to the lower temperature change box, and the second end of the first connecting rod is fixedly connected to the first end of the sliding rod; the first end of the second connecting rod is fixedly connected to the upper temperature change box, and the second end of the second connecting rod is slidably connected to the second end of the sliding rod.

[0010] Preferably, the lateral deformation detection device includes: multiple groups of single-mode bend-resistant optical fibers, a temperature compensation device and an FBG demodulator; the multiple groups of single-mode bend-resistant optical fibers are tightly sleeved on the overall outside of the lining channel body, and the multiple groups of single-mode bend-resistant optical fibers are electrically connected to the FBG demodulator respectively; the temperature compensation device is arranged inside the lining channel body and is electrically connected to the FBG demodulator.

[0011] Preferably, the vertical displacement detection device comprises: a support rod and a fixed rod; the first end of the fixed rod is fixedly connected to the top of the support rod; the second end of the fixed rod is provided with a displacement sensor 321, and the displacement sensor 321 is in contact with the top of the upper temperature change box.

[0012] The present invention also discloses a method for testing temperature conduction and frost heave strain of a concrete lined channel, the testing method comprising:

[0013] S1. Initial testing, which specifically includes:

[0014] FBG demodulator detects the preload of multiple sets of single-mode bending-resistant optical fibers set in the lining channel body. The initial central wavelength is λ B ;

[0015] Multiple temperature sensors detect the initial temperature of the lining channel body;

[0016] S2. The temperature control device is used to provide a predetermined temperature for the lining channel body, which specifically includes:

[0017] The upper temperature-changing box and the lower temperature-changing box are cooled separately to provide a predetermined temperature for the upper and lower ends of the lined channel body;

[0018] S3. Detection after temperature change, which specifically includes:

[0019] Multiple temperature sensors detect the temperature change ΔT in different areas of the lining channel body i ;

[0020] FBG demodulator detects the center wavelength change Δλ of multiple groups of single-mode bend-resistant optical fibers caused by temperature changes Bi ;

[0021] FBG demodulator detects the strain change value ε of multiple groups of single-mode bending-resistant optical fibers i ;

[0022] S4. Obtain frost heave strain parameters:

[0023] Calculate the frost heave strain of the optical fiber:

[0024]

[0025] Among them, ε i is the detected value of the transverse frost heave strain of the single-mode bend-resistant optical fiber (211) in different regions, α is the thermal expansion coefficient of the single-mode bend-resistant optical fiber, ξ is the thermo-optical coefficient of the single-mode bend-resistant optical fiber; p e is the effective photoelastic coefficient of the single-mode bend-resistant optical fiber;

[0026] Transverse frost heave strain ε ai :

[0027] ε ai =ε i -ε'

[0028] Among them, ε ai is the actual value of the transverse frost heave strain in different regions of the lining channel body (11), ε i is the detected value of the frost heave strain of the single-mode bend-resistant optical fiber (211) in different regions, and ε' is the error value detected by the temperature compensation device (212).

[0029] The vertical frost heave strain parameter of the lining channel body (11) is obtained by providing a displacement sensor 321 at the second end of the fixing rod (32).

[0030] Compared with the prior art, the present invention has achieved the following technical effects:

[0031] 1. By arranging multiple temperature sensors along the axial direction of the lining channel body and embedding them into the lining channel body, and using a lateral deformation detection device to detect the deformation of the lining channel body, it is possible to achieve the technical effect of quantitatively analyzing the internal temperature conduction process of the lining channel body and measuring the entire lining channel body;

[0032] 2. The displacement sensor 321 is in contact with the top of the upper temperature-changing box to effectively detect the vertical displacement of the lining channel body after frost heaving; and combined with the winding of the single-mode anti-bending optical fiber on the side wall of the lining channel body, the lateral displacement of the lining channel body after frost heaving can be effectively detected;

[0033] 3. The present invention can simulate the ambient temperature, lining surface temperature and channel foundation soil temperature of lined channels in cold regions. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a schematic diagram of the structure of a device for testing temperature conduction and frost heave strain of a concrete lined channel according to the present invention;

[0035] Figure 2 The diagram is a cross-sectional diagram of a frost heave device for testing temperature conduction and frost heave strain of a concrete lined channel according to the present invention.

[0036] In the figure: 1-frost heave device; 11-lined channel body; 12-upper temperature change box; 13-lower temperature change box; 14-displacement restraint device; 141-first connecting rod; 142-second connecting rod; 143-sliding rod;

[0037] 2-detection device; 21-lateral deformation detection device; 211-single-mode anti-bend optical fiber; 212-temperature compensation device; 2121-temperature compensation grating optical fiber; 2122-protective shell; 213-FBG demodulator; 22-temperature sensor;

[0038] 3-vertical displacement detection device; 31-support rod; 32-fixed rod; 321-displacement sensor. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] Example

[0041] Reference Figure 1-2The device for testing temperature conduction and frost heave strain of concrete lined channels is shown. The test device is placed in a closed test box, and the closed test box can be balanced and temperature controlled by forced air circulation. The test device includes: a frost heave device 1 and a detection device 2. The frost heave device 1 includes a lined channel body 11, an upper temperature change box 12 and a lower temperature change box 13. The upper temperature change box 12 and the lower temperature change box 13 are tightly fixed to the upper and lower ends of the lined channel body 11, respectively, to provide a predetermined temperature for the lined channel body 11.

[0042] Among them, the upper temperature-changing box 12 and the lower temperature-changing box 13 are both water storage barrels, and the upper temperature-changing box 12 and the lower temperature-changing box 13 are both provided with a water inlet and a water outlet for the circulation of cooling medium. The cooling rate can be controlled by controlling the flow rate of the circulating cooling medium, and the upper temperature-changing box 12 and the lower temperature-changing box 13 are kept at a relatively low temperature, so that the upper and lower ends of the lined channel body 11 are in a low-temperature state.

[0043] The material of the closed test box is preferably cold-rolled steel plate, the air circulation device is provided by a centrifugal fan, the condensation method is air cooling, and the heating method is electric heating wire heating.

[0044] The cooling medium is preferably anhydrous ethanol, and the temperature range is -70℃~160℃. The pipeline for conveying anhydrous ethanol is made of high-quality silicone tube, which has the advantage of not freezing and cracking at low temperature, thus ensuring the transmission of anhydrous ethanol.

[0045] The detection device 2 includes a lateral deformation detection device 21 and four temperature sensors 22. The lateral deformation detection device 21 is used to detect the lateral frost heave strain parameters of the lined channel body 11; the four temperature sensors 22 are arranged along the axial direction of the lined channel body 11 and embedded in the interior of the lined channel body 11, and are used to detect the temperature conductivity performance of the lined channel body 11.

[0046] Wherein, holes are drilled every 20 mm in the lining channel body 11, and temperature sensors 22 are installed. The insertion depth of the temperature sensor 22 is 30 mm.

[0047] The lateral deformation detection device 21 includes: 5 groups of single-mode anti-bend optical fibers 211, a temperature compensation device 212 and an FBG demodulator 213. The 5 groups of single-mode anti-bend optical fibers 211 are tightly sleeved on the entire exterior of the lining channel body 11, and the 5 groups of single-mode anti-bend optical fibers 211 are electrically connected to the FBG demodulator 213. The temperature compensation device 212 is arranged inside the lining channel body 11 and is electrically connected to the FBG demodulator 213.

[0048] The five groups of single-mode bend-resistant optical fibers 211 are arranged along the axial direction of the lining channel body 11, and a certain distance is maintained between the five groups of single-mode bend-resistant optical fibers 211. The initial central wavelength of the preload force generated by each group of single-mode bend-resistant optical fibers 211 on the lining channel body 11 is λ B, and ensure that the tensile strain applied by the group of single-mode bend-resistant optical fibers 211 is not less than 350με.

[0049] Five groups of single-mode bend-resistant optical fibers 211 and four temperature sensors 22 are interlaced with each other, the lining channel body 11 is placed in the environmental simulation device, and the central wavelength change Δλ of each section of the single-mode bend-resistant optical fiber 211 is collected by the FBG demodulator Bi .

[0050] The temperature compensation device 212 includes a temperature compensation grating fiber 2121 and a protective shell 2122, wherein the protective shell 2122 seals and wraps the temperature compensation grating fiber 2121, and the temperature compensation grating fiber 2121 is electrically connected to the FBG demodulator 213. The single-mode anti-bend fiber 211 will produce a certain amount of self-strain at low temperatures, and the temperature compensation grating fiber 2121 is used to measure the self-strain ε' of the single-mode anti-bend fiber 211 at low temperatures.

[0051] The preferred material of the protective shell 2122 is PVC, and the protective shell 2122 can prevent the temperature compensation grating optical fiber 2121 from being damaged by cement. In addition, the temperature compensation grating optical fiber 2121 is coated with epoxy resin to achieve waterproof and adhesive effects.

[0052] In order to protect the single-mode bend-resistant optical fiber 211 from external uncertainties during the test and ensure its normal use, a 5 mm thick mortar protective layer is evenly wrapped on the outside of the lined channel body 11, and the single-mode bend-resistant optical fiber is also cast in the mortar protective layer.

[0053] A displacement restraining device 14 is connected between the upper temperature changing box 12 and the lower temperature changing box 13, and the displacement restraining device 14 includes: a first connecting rod 141, a second connecting rod 142 and a sliding rod 143. The first end of the first connecting rod 141 is fixedly connected to the lower temperature changing box 13, and the second end of the first connecting rod 141 is fixedly connected to the first end of the sliding rod 143. The first end of the second connecting rod 142 is fixedly connected to the upper temperature changing box 12, and the second end of the second connecting rod 142 is slidably connected to the second end of the sliding rod 143.

[0054] The present invention uses the slide bar 143 and the first connecting rod 141 to fix the lower temperature change box 13, and the upper temperature change box 12 slides on the slide bar 143 through the second connecting rod 142, which can keep the upper temperature change box 12 and the lower temperature change box 13 in the vertical position to avoid horizontal displacement.

[0055] The height of the slide bar 143 is 1.5 to 1.8 times the height of the upper temperature-changing box 12. The slide bar 143 is much higher than the upper temperature-changing box 12, so that the refrigeration box 12 can be prevented from falling off the top of the slide bar 143 during the rising process.

[0056] The concrete lined channel temperature transfer performance and frost heave test device disclosed in the present invention also includes: a vertical displacement detection device 3, wherein the vertical displacement detection device 3 includes: a support rod 31 and a fixed rod 32, wherein the first end of the fixed rod 32 is fixedly connected to the top end of the support rod 31, and the second end of the fixed rod 32 is provided with a displacement sensor 321, and the displacement sensor 321 is in contact with the top end of the upper temperature change box 12.

[0057] When the lining channel body 11 frost heaves, a squeezing force is provided to the displacement sensor 321 in the vertical direction, so as to measure the vertical displacement of the lining channel body 11 frost heave; in the lateral deformation, the single-mode bend-resistant optical fiber 211 monitors the strain.

[0058] The fixing rod 32 is adjustable at the fixed position of the support rod 31 , so that the vertical displacement detection device 3 can test the vertical displacement of the lined channel bodies 11 of different sizes.

[0059] The present invention also discloses a method for testing temperature conduction and frost heave strain of a concrete lined channel, and the testing method comprises:

[0060] S1. Initial testing, which specifically includes:

[0061] The FBG demodulator 213 detects the preload force of 5 sets of single-mode anti-bend optical fibers 211 set on the lining channel body 11. The initial central wavelength is λ B , thereby ensuring that the bend-resistant optical fiber fits tightly with the lining channel specimen and that the line connection channel is unobstructed;

[0062] After drilling holes in the channel lining 11 and installing the temperature sensor 22, five sets of single-mode bending-resistant optical fibers 211 are set on the channel lining 11 to detect the initial central wavelength of the preload force. B , avoiding deformation of the lining channel body 11 during the process of detecting the drilling and installing the temperature sensor 22;

[0063] The temperature sensor 22 preferably adopts a high-precision contact resistance temperature sensor with a measurement range of -200°C to 350°C; the four temperature sensors 22 detect the initial temperature of the lining channel body 11;

[0064] The initial temperature refers to the temperature inside the lined channel body 11 after the lined channel body 11 is placed in a predetermined environment;

[0065] The predetermined environment is provided by a closed test chamber, and the predetermined environment refers to a simulated low-temperature environment outdoors in the north, preferably -30℃~20℃;

[0066] S2, the temperature control device is used to provide a predetermined temperature for the lining channel body 11, and the temperature of the lining channel body 11 changes from the upper and lower ends to the center;

[0067] The upper temperature changing box 12 and the lower temperature changing box 13 are cooled respectively to provide a predetermined temperature to the upper and lower ends of the lined channel body 11;

[0068] The predetermined temperature refers to the surface temperature of the lining concrete and the frozen soil temperature in simulated severe cold areas;

[0069] During the freezing process, the temperature of the upper temperature-changing box 12 is -25 to -30°C, and the temperature of the lower temperature-changing box 13 is 1°C;

[0070] During the freezing process, the anhydrous ethanol is continuously circulated in the upper temperature-changing box 12 and the lower temperature-changing box 13 to avoid the phenomenon that the refrigerant medium stays in the upper temperature-changing box 12 and the lower temperature-changing box 13 and refrigeration is slow. The total refrigeration time is 5 hours; the predetermined ambient temperature is -5 to -10°C;

[0071] During the melting process, the temperature of the upper temperature-changing box 12 is 10-15°C, the circulation channel of the lower temperature-changing box 13 is closed, and only the circulation channel of the upper temperature-changing box 12 is retained. The heated anhydrous ethanol is continuously circulated in the upper temperature-changing box 12 to avoid the phenomenon that the heating medium stays in the upper temperature-changing box and heats up slowly. The total heating time is 3 hours; during the melting process, the predetermined ambient temperature is 20-25°C;

[0072] With 5 h freezing and 3 h thawing as one freeze-thaw cycle, multiple freeze-thaw cycle measurements were performed;

[0073] S3. Detection after temperature change, which specifically includes:

[0074] Four temperature sensors 22 detect the temperature variation ΔT in different areas of the lining channel body 11 i ;

[0075] The lining channel body 11 cools down from the upper and lower ends to the center, so the four temperature sensors 22 detect the temperature gradient change of the lining channel body 11 from the upper and lower ends to the center;

[0076] The FBG demodulator 213 records the center wavelength change values ​​Δλ of the five groups of single-mode bend-resistant optical fibers 211 caused by temperature changes. Bi FBG demodulator 213 records the strain change value ε of multiple groups of single-mode bending-resistant optical fibers 211 i ;

[0077] The central wavelength variation Δλ of different regions of the lining channel body 11 is detected by using 5 groups of single-mode bend-resistant optical fibers 211 Bi and strain change ε i , the weak points of the lining channel body 11 can be determined;

[0078] S4. Obtain frost heave strain parameters:

[0079] Calculate the transverse frost heave strain of the optical fiber:

[0080]

[0081] Among them, ε i is the detected value of the frost heave strain of the single-mode bend-resistant optical fiber (211) in different regions, α is the thermal expansion coefficient of the single-mode bend-resistant optical fiber 211, ξ is the thermo-optical coefficient of the single-mode bend-resistant optical fiber 211; p e is the effective photoelastic coefficient of the single-mode bend-resistant optical fiber 211;

[0082] Transverse frost heave strain ε ai :

[0083] ε ai =ε i -ε'

[0084] Among them, ε ai is the actual value of the transverse frost heave strain in different regions of the lining channel body (11), ε i is the detected value of the transverse frost heave strain of the single-mode bend-resistant optical fiber (211) in different regions, and ε' is the error value detected by the temperature compensation device (212).

[0085] The vertical frost heave strain parameter of the lining channel body (11) is obtained by providing a displacement sensor 321 at the second end of the fixing rod (32).

[0086] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any slight modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A device for testing temperature conduction and frost heave strain of concrete lined channels, characterized in that: include: A frost heave device (1), the frost heave device (1) comprising a lined channel body (11) and a temperature control device, the temperature control device being used to provide a predetermined temperature for the lined channel body (11); A detection device (2), the detection device (2) comprising a lateral deformation detection device (21), a vertical displacement detection device (3) and a plurality of temperature sensors (22); the lateral deformation detection device (21) is used to detect the lateral frost heave strain parameter of the lining channel body (11) at the predetermined temperature; the vertical displacement detection device (3) is used to detect the vertical frost heave strain parameter of the lining channel body (11) at the predetermined temperature; the plurality of temperature sensors (22) are arranged along the axial direction of the lining channel body (11) and embedded in the interior of the lining channel body (11), and are used to detect the temperature conductivity performance of the lining channel body (11) at the predetermined temperature; The lateral deformation detection device (21) comprises: a plurality of groups of single-mode anti-bend optical fibers (211), a temperature compensation device (212) and an FBG demodulator (213); A plurality of groups of single-mode bend-resistant optical fibers (211) are tightly sleeved on the entire exterior of the lining channel body (11), and the plurality of groups of single-mode bend-resistant optical fibers (211) are electrically connected to the FBG demodulator (213) respectively; A temperature compensation device (212) is arranged inside the lined channel body (11) and is electrically connected to the FBG demodulator (213); The temperature control device is a refrigeration box; there are two temperature control devices, namely an upper temperature changing box (12) and a lower temperature changing box (13); the upper temperature changing box (12) and the lower temperature changing box (13) are respectively tightly fixed to the upper and lower ends of the lined channel body (11); A displacement restraining device (14) is connected between the upper temperature changing box (12) and the lower temperature changing box (13); The displacement restraining device (14) comprises: a first connecting rod (141), a second connecting rod (142) and a sliding rod (143); The first end of the first connecting rod (141) is fixedly connected to the lower temperature change box (13), and the second end of the first connecting rod (141) is fixedly connected to the first end of the sliding rod (143); The first end of the second connecting rod (142) is fixedly connected to the upper temperature change box (12), and the second end of the second connecting rod (142) is slidably connected to the second end of the sliding rod (143).

2. The testing device according to claim 1, characterized in that: The vertical displacement detection device (3) comprises: a support rod (31), a fixing rod (32) and a displacement sensor (321); The first end of the fixing rod (32) is fixedly connected to the top end of the supporting rod (31); the second end of the fixing rod (32) is fixedly connected to the displacement sensor (321), and the displacement sensor 321 is in contact with the top end of the upper temperature-changing box (12).

3. A method for testing temperature conduction and frost heave strain of a concrete lined channel, characterized in that: Applied to the device of any one of claims 1 to 2, the testing method comprises: S1. Initial testing, which specifically includes: The FBG demodulator (213) detects the initial central wavelength of the preload force of the multiple groups of single-mode anti-bend optical fibers (211) sleeved on the lining channel body (11) as λ B ; The plurality of temperature sensors (22) detect the initial temperature of the lined channel body (11); S2. The temperature control device is used to provide a predetermined temperature for the lined channel body (11), and specifically comprises: The upper temperature changing box (12) and the lower temperature changing box (13) are cooled respectively to provide a predetermined temperature to the upper and lower ends of the lined channel body (11); S3. Detection after temperature change, which specifically includes: The plurality of temperature sensors (22) detect temperature changes ΔT in different areas of the lined channel body (11). i ; The FBG demodulator (213) detects the center wavelength change values ​​Δλ of the plurality of groups of single-mode bend-resistant optical fibers (211) caused by temperature changes. Bi ; The FBG demodulator (213) detects the strain change values ​​ε of the multiple groups of the single-mode bend-resistant optical fibers (211). i ; The displacement sensor (321) detects a change in the vertical displacement of the lined channel body (11); S4. Obtain frost heave strain parameters: Calculate the transverse frost heave strain of the optical fiber: Among them, ε i is the detected value of the transverse frost heave strain of the single-mode bend-resistant optical fiber (211) in different regions, α is the thermal expansion coefficient of the single-mode bend-resistant optical fiber (211), and ξ is the thermo-optical coefficient of the single-mode bend-resistant optical fiber (211); p e is the effective photoelastic coefficient of the single-mode bend-resistant optical fiber (211); Transverse frost heave strain ε ai : e ai =e i -e' Among them, ε ai is the actual value of the transverse frost heave strain in different regions of the lining channel body (11), ε i is the detected value of the frost heave strain of the single-mode bend-resistant optical fiber (211) in different regions, and ε' is the error value detected by the temperature compensation device (212); The vertical frost heave strain parameter of the lining channel body (11) is obtained by providing a displacement sensor 321 at the second end of the fixing rod (32).

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