Device for detecting uniformity of fiber reinforced solidified soil

Abstract

The invention discloses a device for detecting uniformity of fiber solidified soil, which belongs to the technical field of geotechnical engineering detection and comprises a device base, a support column, a top cross beam, a vertical bending element probe group signal transmitting / receiving end, a limiter, a transverse bending element probe group signal transmitting / receiving end and a transverse support system, each vertical bending element probe group signal transmitting / receiving end comprises two groups of eight bending element probes and a hollow cylindrical iron block for packaging the probes, and each transverse bending element probe signal transmitting / receiving end comprises one group of four bending element probes and a rectangular hollow iron block for packaging the element probes. According to the device for detecting the uniformity of the fiber solidified soil, the shear wave velocities Vs at different positions of a sample can be measured, the shear wave velocities Vs are processed, a range coefficient alpha reflecting the uniformity of the sample can be obtained through calculation, and the uniformity distribution condition of fibers in the solidified soil can be accurately evaluated.

Description

Technical Field

[0001] The present invention belongs to the field of geotechnical engineering detection technology, and in particular relates to a geotechnical detection technology based on bending element technology and applied to the uniformity of fiber-solidified soil. Background Art

[0002] Stabilized soil has been widely used in various backfill and roadbed projects because it can effectively treat waste soil while providing the required strength. Adding fibers to stabilized soil can effectively enhance the soil's strength, toughness, and integrity. However, due to factors such as the mixing process and the fiber's inherent dispersion, the fibers can be unevenly distributed within the soil, with large numbers of fibers clumping together. This can lead to uneven soil strength and even create new weak points due to the incorporation of fibers. Traditional testing methods are unable to measure the fiber distribution within the soil.

[0003] Bending element testing technology has been gradually applied to soil shear wave velocity V since the beginning of the 21st century. s In the measurement of shear wave velocity V s It has important reference significance for the calculation of soil dynamic response and the evaluation of roadbed and foundation quality. The bending element test method has the characteristics of simple and clear technical principles, convenient operation steps and non-destructive testing. Traditional bending element test technology is mostly combined with the triaxial tester in geotechnical specimens. There is only one pair of shear wave transmitting end and receiving end, and the size of the specimen is fixed. It aims to measure the shear wave velocity change of the specimen under different stress paths. CN118913852A discloses a method for preparing and removing sandy soil specimens connected to a three-dimensional bending element probe. Although it has been improved on the traditional device, two pairs of horizontal bending element probes are set in the horizontal direction, so that the shear wave velocity V in the three directions of the specimen can be obtained. s However, since the device only has a pair of probes in each dimension, it is impossible to obtain the shear wave velocity V in all directions of the sample. s In addition, due to the significant difference in boundary conditions when shear waves propagate in the horizontal and vertical directions, shear wave velocities in different directions cannot be used to compare and judge the uniformity of the sample. CN118915607A discloses a PLC-based bending element array control system and its control method, which can obtain the three-dimensional shear wave velocity V in the soil space. s distribution pattern, but this system is applicable to the model box and is not specifically designed for the fixation of specimens at the unit scale.

[0004] If the uniformity of fiber reinforced soil samples is to be tested using bending element testing technology, it is necessary to obtain at least three shear wave velocities V of the sample in a certain direction. sStatistical analysis is performed, and boundary conditions are taken into account so that the measured shear wave velocity V s In addition, the detection device should be different from the traditional bending element detection system combined with the triaxial tester, and should have a wide range of applicability, capable of detecting the shear wave velocity V at different positions of specimens of different sizes. s , and then analyze the uniformity of the fiber-solidified soil. Summary of the Invention

[0005] The purpose of the present invention is to overcome the shortcomings of the existing technology and provide a fiber reinforced soil uniformity detection device based on bending element technology. The positions of the vertical and horizontal detection components in the detection device can be adjusted, so that different positions of the same sample can be detected and samples of different sizes can be adapted. The shear wave velocity V of the sample in a certain direction is measured by the bending element probe group. s The distribution of fibers in the sample can be determined by simply processing and calculating the measured data to obtain the range coefficient α, which can be used to judge the uniformity of fiber distribution inside the sample.

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

[0007] A device for testing the uniformity of fiber-stabilized soil comprises a device base, support columns, a vertical support system, a transverse support system, a vertical bending element signal system, and a transverse bending element signal system. At least two support columns are vertically fixedly mounted on the device base, and a sample to be tested is mounted between the support columns. The vertical bending element signal system comprises a vertical bending element signal transmitting end and a vertical bending element signal receiving end. The transverse bending element signal system comprises a transverse bending element signal transmitting end and a transverse bending element signal receiving end. Each signal end is mounted around and faces the sample.

[0008] The vertical bending element signal receiving end is fixedly connected to the device base, and the horizontal support system is fixedly connected to the device base; the vertical bending element signal transmitting end and the vertical bending element signal receiving end are fixed by the vertical support system, and the signal ends are directed toward the middle positions of the top and bottom surfaces of the sample; the horizontal bending element signal transmitting end and the horizontal bending element signal receiving end are fixed by the horizontal support system, and the signal ends are directed toward the middle positions of the vertical side surfaces of the sample respectively;

[0009] The vertical bending element signal transmitting end and the vertical bending element signal receiving end are respectively provided with two groups of bending element probe groups, each group includes four bending element probes, and the transverse bending element signal transmitting end and the transverse bending element signal receiving end are respectively provided with one group of bending element probe groups, each group includes at least four bending element probes. The bending element detection element part of each bending element probe body is encapsulated in the probe module, and the tip of each bending element probe protrudes from the surface of the probe module to form an induction test end to detect the uniformity of the fiber-cured soil sample.

[0010] Preferably, the arrangement of the bending element probe group is designed for the purpose of measuring uniformity, and the two groups of bending element probe groups respectively set at the vertical bending element signal transmitting end and the vertical bending element signal receiving end include a first bending element probe group and a second bending element probe group; wherein the four bending element probes of the first bending element probe group are arranged symmetrically with the center of the circular base plate where the sensing test end is located as the center of the circle, and are distributed at an average interval of 90°; the four bending element probes of the second bending element probe group are also arranged symmetrically with the center of the circular base plate where the sensing test end is located as the center of the circle, and are distributed at an average interval of 90°; and each probe is also arranged with the center of the circular base plate where the sensing test end is located as the center of the circle, so that the relative position of the second bending element probe group relative to the first bending element probe group is rotated 45° and staggered, so that the distribution form of a total of 8 bending element probes in the two groups of bending element probe groups on the same sensing test end surface forms a "M"-shaped structure; the distances between the bending element probes of different groups and the center point of the circular base plate of the same sensing test end are different, so that two independent groups of shear wave velocities reflecting the lateral uniformity of the sample can be measured at one time.

[0011] Preferably, the sizes of the bending element probes of the sensing test end are the same, and the radius of the circular base plate where the sensing test end is located is r; for the same circular base plate, the distance between the centers of the four bending element probes of the first bending element probe group and the center of the circular base plate is r / 3, and the four bending element probes of the first bending element probe group do not contact each other; the distance between the centers of the four bending element probes of the second bending element probe group and the center of the circular base plate is 2r / 3.

[0012] Preferably, the arrangement of the bending element probe group is designed for the purpose of measuring uniformity. The four bending element probes of a group of transverse bending element probes respectively arranged at the transverse bending element signal transmitting end and the transverse bending element signal receiving end are arranged evenly in a straight line and are arranged on the rectangular base plate where the sensing test end is located. A group of shear wave velocities reflecting the vertical uniformity of the sample can be measured at one time.

[0013] Preferably, the vertical support system includes a top beam and a limiter, holes are opened near both ends of the top beam and the support columns are inserted into the holes, the top beam is horizontally mounted on the support column, and the top beam is adjusted to rise and fall in the vertical direction of the support column, a limiter is set in the middle of the top beam, the limiter passes through the through hole in the middle of the top beam, so that the limiter can be freely raised and lowered in the through hole along the direction of gravity, the limiter is fixedly connected to the top of the vertical bending element signal transmitting end through the connecting module to form an integrated downward pressure component; the upper half of the support column is provided with a thread and is equipped with a corresponding nut, the top beam and the support column are connected by a vertical height adjustment nut to adjust the position of the top beam.

[0014] Preferably, the transverse support system includes a transverse support rod, a transverse sleeve rod, a vertical support rod, and a vertical sleeve rod; the vertical sleeve rod and the vertical support rod are connected by a slide rail, and the vertical sleeve rod and the vertical support rod are fixedly connected by tightening a first limit nut; the transverse sleeve rod and the transverse support rod are also connected by a slide rail, so that one end of the transverse support rod is fixedly connected to the vertical support rod, and the transverse sleeve rod and the transverse support rod are fixedly connected by tightening a second limit nut; the other end of the transverse support rod is respectively supported and connected to the transverse bending element signal transmitting end or the transverse bending element signal receiving end. Further preferably, one side of the inner wall of the sleeve rod is connected to the support rod by a slide rail structure, and the position of the telescopic rod is controlled by a limit nut.

[0015] Preferably, each bending element probe comprises a detection element and a polycarbonate tip, which are connected and fixed by an epoxy resin portion. Epoxy resin has high strength, good corrosion resistance, and good insulation properties, allowing the detection element and the polycarbonate tip to deform synergistically. The polycarbonate tip enables the bending element probe assembly to be smoothly inserted into the surface layer of the specimen and tightly bonded to the specimen. Polycarbonate has high hardness and strength, and the polycarbonate tip enables the bending element probe assembly to be smoothly inserted into the specimen and tightly bonded to the specimen.

[0016] Preferably, the bending element probe assembly is positioned and installed through a hole reserved in the hollow cylindrical iron block, and the bending element probe is fixedly connected to the hollow cylindrical iron block. After the bending element probe is installed, epoxy resin is poured into the inner cavity of the hollow cylindrical iron block. After the epoxy resin cures, it forms an epoxy resin portion, forming an integral structure between the bending element probe body and the hollow cylindrical iron block. The signal transmitting end of the bending element probe assembly has the same structure as the signal receiving end of the bending element, and the curing connection ability of the epoxy resin is utilized to ensure the integrity between the bending element probe and the hollow cylindrical iron block.

[0017] Preferably, by adjusting the relative position of the bending element probe and the sample to be tested, the shear wave velocity V at different angles θ and different heights h of the sample is measured. s, thereby obtaining the shear wave velocity V inside the sample s The three-dimensional distribution of .

[0018] Preferably, the shear wave velocity V of the sample is measured s , the shear wave velocity V is obtained by processing and calculation s The range coefficient α is used to judge and evaluate the uniformity of the sample. The calculation formula of the range coefficient α is: α=R / μ;

[0019] R in the formula is the shear wave velocity V s The range of μ is the shear wave velocity V s The average value of

[0020] The sample uniformity is evaluated according to the following standards:

[0021] The sample uniformity is excellent when α is less than 5%; the sample uniformity is good when 5% is less than α and less than 10%; the sample uniformity is fair when 10% is less than α and less than 15%; the sample uniformity is qualified when α is greater than 20% and the sample uniformity is unqualified.

[0022] Compared with the prior art, the present invention has the following obvious outstanding substantial features and significant advantages:

[0023] 1. The present invention takes into account the effect of boundary conditions on shear wave velocity V s To reduce the influence of the bending element probe, the vertical bending element probe group is arranged symmetrically, and the transverse bending element probe group is evenly distributed, so that the shear wave velocity V measured by each group of bending element probe is s Under the same or similar boundary conditions, the comparability of test data is significantly improved;

[0024] 2. The present invention can measure the representative shear wave velocity V in the vertical and horizontal directions of the sample by using a vertical bending element probe group and a linearly evenly distributed horizontal bending element probe group. s , by simply processing and analyzing the measured data, we can obtain statistical indicators reflecting the degree of uniformity of the sample in the horizontal and vertical directions;

[0025] 3. The present invention bonds a polycarbonate tip to the bending element detection component, making it easier to insert the bending element probe assembly into the sample and causing less disturbance to the sample, helping to improve the accuracy and authenticity of the test results.

[0026] 4. The present invention uses a lateral support system with adjustable height and horizontal position, a top crossbeam with adjustable height, and a movable vertical bending element signal transmitter to make the device suitable for testing samples of various sizes and obtain the sample shear wave velocity V s The three-dimensional distribution of BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of an embodiment of the device for detecting uniformity of fiber reinforced solidified soil according to the present invention.

[0028] Figure 2 It is a schematic diagram of the structure of the vertical bending element probe signal group transmitting / receiving end of the present invention.

[0029] Figure 3 It is a schematic diagram of the structure of the transmitting / receiving end of the transverse bending element probe signal group of the present invention.

[0030] Figure 4 This invention Figure 2 and Figure 3 Schematic diagram of the structure of the medium bending element probe.

[0031] The corresponding relationship between the reference numerals and components is as follows:

[0032] 101. Stopper; 102. Vertical height adjustment nut; 103. Top crossbeam; 104. Horizontal support rod; 105. Horizontal sleeve rod; 106. Vertical support rod; 107. Vertical sleeve rod; 108. Second stopper nut; 109. Device base; 110 Support column; 111. First stopper nut; 201. Vertical bending element signal transmitter; 202. Vertical bending element signal receiver; 301. Horizontal bending element signal transmitter; 302. Horizontal bending element signal receiving end; 2a, first vertical bending element probe group, the probe center position is r / 3 away from the center of the circular base plate, r is the center of the circular base plate; 2b, second vertical bending element probe group, the probe center position is 2r / 3 away from the center of the circular base plate, r is the center of the circular base plate; 3a, horizontal bending element probe group; 401, piezoelectric ceramic plate; 402, brass plate; 403, epoxy resin part; 404, polycarbonate tip. DETAILED DESCRIPTION

[0033] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0034] Example 1

[0035] In this embodiment, if Figure 1As shown, a device for detecting uniformity of fiber-stabilized soil includes a device base 109, support columns 110, a vertical support system, a transverse support system, a vertical bending element signal system, and a transverse bending element signal system. At least two support columns 110 are vertically fixedly mounted on the device base 109, and a sample to be tested is installed between the support columns. The vertical bending element signal system includes a vertical bending element signal transmitting end 201 and a vertical bending element signal receiving end 202. The transverse bending element signal system includes a transverse bending element signal transmitting end 301 and a transverse bending element signal receiving end 302. Each signal end is installed around and faces the sample.

[0036] The vertical bending element signal receiving end 202 is fixedly connected to the device base 109, and the horizontal support system is fixedly connected to the device base 109; the vertical bending element signal transmitting end 201 and the vertical bending element signal receiving end 202 are fixed in position by the vertical support system, and the signal ends are directed toward the middle positions of the top and bottom surfaces of the sample; the horizontal bending element signal transmitting end 301 and the horizontal bending element signal receiving end 302 are fixed in position by the horizontal support system, and the signal ends are directed toward the middle positions of the vertical side surfaces of the sample respectively;

[0037] The vertical bending element signal transmitting end 201 and the vertical bending element signal receiving end 202 are respectively provided with two groups of bending element probe groups, each group includes four bending element probes, and the transverse bending element signal transmitting end 301 and the transverse bending element signal receiving end 302 are respectively provided with one group of bending element probe groups, each group includes at least four bending element probes. The bending element detection element part of each bending element probe body is encapsulated in the probe module, and the tip of each bending element probe protrudes from the surface of the probe module to form an induction test end to detect the uniformity of the fiber-cured soil sample.

[0038] This embodiment of the fiber-reinforced soil uniformity testing device, based on bending element technology, features adjustable positions of the testing components supported by the vertical and horizontal support systems. This allows testing at different locations on the same specimen, and is adaptable to specimens of varying sizes. The device can measure shear wave velocities at different locations on specimens of varying sizes, thereby analyzing the uniformity of the fiber-reinforced soil.

[0039] Example 2

[0040] This embodiment is basically the same as the first embodiment, with the following special features:

[0041] In this embodiment, if Figure 1 and Figure 2As shown, the vertical bending element signal transmitting end 201 and the vertical bending element signal receiving end 202 are respectively provided with two groups of bending element probe groups, including a first bending element probe group 2a and a second bending element probe group 2b; wherein the four bending element probes of the first bending element probe group 2a are arranged symmetrically with the center of the circular base plate where the sensing test end is located as the center of the circle, and are distributed at an average interval of 90°; the four bending element probes of the second bending element probe group 2b are also arranged symmetrically with the center of the circular base plate where the sensing test end is located as the center of the circle, and are distributed at an average interval of 90°; and each probe is also rotated 45° relative to the first bending element probe group 2a with the center of the circular base plate where the sensing test end is located as the center of the circle, so that the relative position of the second bending element probe group 2b is staggered by 45° relative to the first bending element probe group 2a, so that the distribution form of the total 8 bending element probes in the two groups of bending element probe groups on the same sensing test end surface forms a "M"-shaped structure; the bending element probes of different groups on the same sensing test end are at different distances from the center point of the circular base plate, so that two independent groups of shear wave velocities reflecting the lateral uniformity of the sample can be measured at one time.

[0042] like Figure 1 and Figure 2 As shown, the bending element probes of the inductive test end of this embodiment preferably have the same dimensions, and the circular base plate on which the inductive test end resides has a radius of r. For the same circular base plate, the centers of the four bending element probes of the first bending element probe group 2a are spaced apart by a distance of r / 3 from the center of the circular base plate, and the four bending element probes of the first bending element probe group 2a do not contact each other. The centers of the four bending element probes of the second bending element probe group 2b are spaced apart by a distance of 2r / 3 from the center of the circular base plate. The tips of the bending element probes of the inductive test end of this embodiment preferably have a wedge-shaped portion, which effectively releases the sample and ensures measurement accuracy and response sensitivity.

[0043] This embodiment takes into account the effect of boundary conditions on the shear wave velocity V s The vertical bending element probe groups are arranged symmetrically so that the shear wave velocity V measured by each group of bending element probes is s Under the same or similar boundary conditions, the comparability of test data is significantly improved.

[0044] Example 3

[0045] This embodiment is basically the same as the above embodiment, with the following special features:

[0046] In this embodiment, if Figure 1 and Figure 3As shown, the four bending element probes of a group of transverse bending element probes 3a respectively set at the transverse bending element signal transmitting end 301 and the transverse bending element signal receiving end 302 are evenly arranged in a straight line and set on the rectangular bottom plate where the induction test end is located, which can measure a group of shear wave velocities reflecting the vertical uniformity of the sample at one time.

[0047] This embodiment takes into account the effect of boundary conditions on the shear wave velocity V s The transverse bending element probe groups are evenly distributed so that the shear wave velocity V measured by each group of bending element probes is s Under the same or similar boundary conditions, the comparability of test data is significantly improved.

[0048] Example 4

[0049] This embodiment is basically the same as the above embodiment, with the following special features:

[0050] In this embodiment, if Figure 1 As shown, the vertical support system includes a top beam 103 and a limiter 101. Holes are opened near both ends of the top beam 103 and the support column 110 is inserted into the holes. The top beam 103 is horizontally mounted on the support column 110. The top beam 103 is adjusted to rise and fall in the vertical direction of the support column 110. A limiter 101 is set in the middle of the top beam 103. The limiter 101 passes through the through hole in the middle of the top beam 103, so that the limiter 101 can be freely raised and lowered in the through hole along the direction of gravity. The limiter 101 is fixedly connected to the top of the vertical bending element signal transmitting end 201 through the connecting module to form an integrated downward pressure component; the upper half of the support column 110 is provided with a thread and is equipped with a corresponding nut. The top beam 103 and the support column 110 are connected by a vertical height adjustment nut 102 to adjust the position of the top beam 103.

[0051] In this embodiment, if Figure 1 As shown, the transverse support system includes a transverse support rod 104, a transverse sleeve rod 105, a vertical support rod 106, and a vertical sleeve rod 107; the vertical sleeve rod 107 and the vertical support rod 106 are connected by a slide rail, and the vertical sleeve rod 107 and the vertical support rod 106 are fixedly connected by tightening the first limit nut 111; the transverse sleeve rod 105 and the transverse support rod 104 are also connected by a slide rail, so that one end of the transverse support rod 104 is fixedly connected to the vertical support rod 106, and the transverse sleeve rod 105 and the transverse support rod 104 are fixedly connected by tightening the second limit nut 108; the other end of the transverse support rod 104 supports and connects the transverse bending element signal transmitting end 301 or the transverse bending element signal receiving end 302 respectively.

[0052] In this embodiment, if Figure 1As shown in the figure, by adjusting the relative position of the bending element probe and the sample to be tested, the shear wave velocity V at different angles θ and different heights h of the sample is measured. s , thereby obtaining the shear wave velocity V inside the sample s The three-dimensional distribution of .

[0053] This embodiment uses a lateral support system with adjustable height and horizontal position, a top crossbeam with adjustable height, and a movable vertical bending element signal transmitter to make the device applicable to the detection of samples of various sizes, and obtain the sample shear wave velocity V s The three-dimensional distribution of .

[0054] Example 5

[0055] This embodiment is basically the same as the above embodiment, with the following special features:

[0056] In this embodiment, if Figure 1-4 As shown, each of the bending element probes includes a detection element and a polycarbonate tip 404, which are connected and fixed by an epoxy resin portion 403, so that the detection element and the polycarbonate tip 404 can be deformed cooperatively. The polycarbonate tip 404 enables the bending element probe group to be smoothly inserted into the surface of the sample and tightly combined with the sample.

[0057] In this embodiment, if Figure 1-4 As shown, the bending element probe group is positioned and installed through the holes reserved on the hollow cylindrical iron block, and the bending element probe is fixedly connected to the hollow cylindrical iron block. After the bending element probe is installed, epoxy resin is poured into the inner cavity of the hollow cylindrical iron block. After the epoxy resin is cured, the epoxy resin part 403 is formed, so that an integral structure is formed between the bending element probe body and the hollow cylindrical iron block.

[0058] In this embodiment, a polycarbonate tip is bonded to the bending element detection component, which makes it easier to insert the bending element probe assembly into the sample and produces less disturbance to the sample, thereby helping to improve the accuracy and authenticity of the detection results.

[0059] Example 6

[0060] This embodiment is basically the same as the above embodiment, with the following special features:

[0061] In this embodiment, the shear wave velocity V of the sample is measured. s , the shear wave velocity V is obtained by processing and calculation s The degree of uniformity of the sample is judged and evaluated by the range coefficient α. The calculation formula of the range coefficient α is: α=R / μ;

[0062] R in the formula is the shear wave velocity V sThe range of μ is the shear wave velocity V s The average value of

[0063] The sample uniformity is evaluated according to the following standards:

[0064] The sample uniformity is excellent when α is less than 5%; the sample uniformity is good when 5% is less than α and less than 10%; the sample uniformity is fair when 10% is less than α and less than 15%; the sample uniformity is qualified when α is greater than 20% and the sample uniformity is unqualified.

[0065] The present invention can measure the representative shear wave velocity V in the vertical and horizontal directions of the sample by using a vertical bending element probe group and a linearly evenly distributed horizontal bending element probe group. s By simply processing and analyzing the measured data, statistical indicators reflecting the degree of horizontal and vertical uniformity of the sample can be obtained, which can realize the combination of quantitative analysis and qualitative analysis. It can be further combined with the inference analysis model to obtain richer measurement information output.

[0066] Example 7

[0067] This embodiment is basically the same as the above embodiment, with the following special features:

[0068] In this embodiment, if Figure 1 As shown, the device for detecting uniformity of fiber-stabilized soil in this embodiment has a more specific technical solution:

[0069] The device of this embodiment includes a limiter 101 for supporting and fixing the test sample, a vertical height adjustment nut 102, a top crossbeam 103, a horizontal support rod 104, a horizontal sleeve rod 105, a vertical support rod 106, a vertical sleeve rod 107, a second limit nut 108, a device base 109, a support column 110, and a first limit nut 111; for detecting the shear wave velocity V sThe vertical bending element signal transmitting end 201, the vertical bending element signal receiving end 202, the lateral bending element signal transmitting end 301, and the lateral bending element signal receiving end 302. The vertical bending element probe group signal transmitting end 201 includes 2 groups of 8 bending element probes and a hollow cylindrical iron block that encapsulates the bending element probes. The vertical bending element probe group signal receiving end 202 includes 2 groups of 8 bending element probes and a cylindrical hollow iron block that encapsulates the bending element probes. The vertical bending element probe group signal transmitting end 201 is connected to the limiter 101 through a solid cylindrical iron block, and the whole is inserted into the circular opening reserved in the center of the top beam 103. The vertical bending element probe group signal receiving end 201 is fixedly connected to the device base 109. The transverse bending element signal transmitting end 301 and the transverse bending element signal receiving end 302 each include 1 group of 4 bending element probes and a rectangular hollow iron block that encapsulates the bending element probes. The transverse bending element signal transmitting end 301 and the transverse bending element signal receiving end 302 are fixedly connected to the transverse support system, and the transverse support system is fixedly connected to the device base.

[0070] The stopper 101 and the vertical bending element signal transmitting end 201 are connected as a whole by a solid cylindrical steel block. The solid cylindrical steel block has a large mass and is convenient for inserting the bending element probe into the soil sample after being connected to the vertical bending element signal transmitting end 201. The length of the solid cylindrical steel block is h s It is 1 / 3 of the length H of the support column 110. A hole is opened at the center of the top crossbeam 103, and the hole diameter is slightly larger than the diameter of the solid cylindrical steel block, so that the vertical bending element signal transmitting end 201 can move freely up and down.

[0071] The top crossbeam 103 is connected to the support column 110 through a vertical height adjustment nut 102, and the position of the top crossbeam 103 is also controlled by the vertical height adjustment nut 102. The upper 2 / 3 of the support column is provided with threads, so that the vertical bending element signal transmitting end can move within the length H of the support column 110.

[0072] The lateral support system of the device is composed of the transverse support rod 104, the transverse sleeve rod 105, the vertical support rod 106, and the vertical sleeve rod 107. The vertical support rod 106 is a square hollow iron column, and the vertical sleeve rod 107 is also a square hollow iron column. The vertical sleeve rod 107 is shorter than the vertical support rod 106. The vertical sleeve rod 107 and the vertical support rod 106 are connected by a slide rail. The vertical sleeve rod 107 and the vertical support rod 106 are fixedly connected by tightening the second limit nut 111. The transverse support rod 104 is a square hollow iron column, and the transverse sleeve rod 107 is also a square hollow iron column. The transverse sleeve rod 105 is shorter than the transverse support rod 104. The transverse sleeve rod 105 and the transverse support rod 104 are also connected by a slide rail. The transverse sleeve rod 105 and the transverse support rod 104 are fixedly connected by tightening the first limit nut 108.

[0073] The vertical bending element signal receiving end 202 is fixedly connected to the device base 109 , and the diameter of the circular bottom plate of the vertical bending element signal receiving end 202 is the same as that of the vertical bending element signal transmitting end 201 .

[0074] The lateral bending signal transmitter 301 and the lateral bending signal receiver 302 are rigidly connected to the lateral support rod 104. The positions of the lateral bending signal transmitter 301 and the lateral bending signal receiver 302 are adjusted by a slide rail between the lateral sleeve rod 105 and the lateral support rod 104, and the positions of the lateral bending signal transmitter 301 and the lateral bending signal receiver 302 are fixed by tightening the first limit nut 108.

[0075] The arrangement of the bending element probes at the vertical bending element signal transmitting end 201 and the receiving end 202 is as follows: Figure 2 As shown, the bending element probes are radially arranged on the circular base plate, with two groups of four probes in each group, one every 90°. The two groups of bending element probes are staggered 45°. The bending element center of the first bending element probe group 2a is r / 3 away from the center of the circle, and the bending element center of the second bending element probe group 2b is 2r / 3 away from the center of the circle. r is the radius of the circular base plate, which is 1 / 4 of the length of the top beam L. Within each group, because the bending element probes are symmetrically arranged about the center of the circular base plate, the boundary conditions of each bending element probe are the same, and the measured shear wave velocity V s It is statistically significant and can be further analyzed and processed.

[0076] The arrangement of the transverse bending element probe group 3a of the transverse bending element signal transmitting end 301 and the transverse bending element signal receiving end 302 is as follows: Figure 3 As shown, the bending element probes are evenly arranged in a straight line on the rectangular base plate, and the distance between the bending elements is h r / 25,h r The length of the rectangular bottom plate is 1 / 3 of the height H of the support column 110. The lateral bending element signal transmitting end 301 and the lateral bending element signal receiving end 302 should be located in the middle of the sample during testing so that each bending element probe is under similar boundary conditions.

[0077] The relative relationship between the dimensions of the various components of this device has been basically given, and its specific dimensions can be adjusted according to the size of the test specimen. Taking the unconfined compressive strength cylindrical specimen commonly used in geotechnical tests as an example, its dimensions are usually 39.1mm in diameter and 80mm in height. In this case, the dimensions of the various components of the test device are as follows: the length H of the support column 110 is 150mm, the length h of the solid cylindrical steel block is 150mm, and the length h of the solid cylindrical steel block is 150mm. s The radius of the circular bottom plate is 50 mm, the radius R of the circular bottom plate is 21 mm, the distance between the bending element of group 2a and the center of the circle is 7 mm, the distance between the bending element of group 2b and the center of the circle is 14 mm, the length L of the top crossbeam 103 is 84 mm, and the length h of the rectangular bottom plate is 103. rThe distance between the bending elements in group 3a is 2 mm.

[0078] Figure 2 and Figure 3 The bending element probe structure in Figure 4 As shown, it includes a piezoelectric ceramic plate 401, a brass plate 402, epoxy resin 403, and a polycarbonate tip 404. Epoxy resin 403 is used to bond the piezoelectric ceramic plate 401, the brass plate 402, and the polycarbonate tip 404. The bending element probe is 15 mm long, 10 mm wide, and 1.2 mm thick. The bending element detection element includes the piezoelectric ceramic plate 401 and the brass plate 402. The polycarbonate tip 404 is inserted into the sample to a depth of 2 mm. The tip of the polycarbonate tip 404 is 0.5 mm long. The bending element probe is inserted into the sample to a depth of 2.5 mm, with the remaining portion inserted into the base plate.

[0079] When the device of this embodiment is used specifically:

[0080] First, adjust the vertical height adjustment nut 102 according to the sample size, adjust the top crossbeam 103 to a position slightly higher than the sample height, lift the vertical bending element signal transmitting end 201, place the sample at the center of the vertical bending element signal receiving end 202, and gently press the stopper 101 so that all bending element probes are inserted into the sample surface;

[0081] Then, adjust the vertical support rod 106 and the vertical sleeve rod 107 so that the lateral bending element signal transmitting end 301 and the receiving end 302 are flush and located in the middle of the sample to be tested, tighten the second limit nut 111, adjust the lateral support rod 104 and the lateral sleeve rod 105 so that all the bending element probes on the bending element signal transmitting end 301 and the receiving end 302 are inserted into the surface of the sample, and tighten all the first limit nuts 108;

[0082] Next, connect and turn on the detection equipment connected to the bending element probe and measure the shear wave velocity V s If the sample size is large or the accuracy of the test results is required to be high, the shear wave velocity V at different angles θ and different heights h of the sample can be measured by rotating the sample and adjusting the relative position of the transverse bending element signal transmitting end 301 / receiving end 302 and the sample. s , obtain the shear wave velocity V in the sample s The three-dimensional distribution of

[0083] Finally, for the shear wave velocity V s Process, count and analyze, and remove the shear wave velocity V s For data with a mean value μ that differs by more than 40%, the range coefficient α is calculated to determine the uniformity of the sample. If the sample is measured multiple times and at multiple locations, the range coefficient α is averaged to determine the uniformity of the sample.

[0084] The present invention relates to a device for detecting the uniformity of fiber-cured soil, belonging to the field of geotechnical engineering detection technology, and includes: a device base, a support column, a top crossbeam, a vertical bending element probe group signal transmitting / receiving end, a stopper, a transverse bending element probe group signal transmitting / receiving end, and a transverse support system. The vertical bending element probe group signal transmitting / receiving end each includes two groups of eight bending element probes and a hollow cylindrical iron block encapsulating the probes, and the transverse bending element probe signal transmitting / receiving end each includes one group of four bending element probes and a rectangular hollow iron block encapsulating the element probes. The present invention adopts a device for detecting the uniformity of fiber-cured soil according to the above embodiment, which can measure the shear wave velocity V at different positions of the sample. s , for shear wave velocity V s The range coefficient α reflecting the uniformity of the sample can be obtained through processing and calculation, which is helpful to accurately evaluate the uniform distribution of fibers inside the solidified soil.

[0085] Finally, it should be noted that: Figure 1-4 The present invention is described in detail in the following embodiments, including the device structure and the detection method. Those skilled in the art will appreciate that they can propose various improvements based on the above descriptions. Therefore, certain details in the embodiments should not be construed as limiting the present invention. The scope of protection of the present invention shall be determined by the scope defined in the appended claims.

Claims

1. A device for detecting uniformity of fiber-cured soil, comprising a device base (109), support columns (110), a vertical support system, a transverse support system, a vertical bending element signal system, and a transverse bending element signal system; at least two support columns (110) are vertically fixedly mounted on the device base (109), and a sample to be tested is mounted between the support columns; the vertical bending element signal system comprises a vertical bending element signal transmitting end (201) and a vertical bending element signal receiving end (202); the transverse bending element signal system comprises a transverse bending element signal transmitting end (301) and a transverse bending element signal receiving end (302); each signal end is mounted around and facing the sample; and the device is characterized in that: The vertical bending element signal receiving end (202) is fixedly connected to the device base (109), and the horizontal support system is fixedly connected to the device base (109); the vertical bending element signal transmitting end (201) and the vertical bending element signal receiving end (202) are fixed by the vertical support system, and the signal ends are directed toward the middle positions of the top and bottom surfaces of the sample; the horizontal bending element signal transmitting end (301) and the horizontal bending element signal receiving end (302) are fixed by the horizontal support system, and the signal ends are directed toward the middle positions of the vertical side surfaces of the sample respectively; The vertical bending element signal transmitting end (201) and the vertical bending element signal receiving end (202) are respectively provided with two groups of bending element probe groups, each group including four bending element probes; the transverse bending element signal transmitting end (301) and the transverse bending element signal receiving end (302) are respectively provided with one group of bending element probe groups, each group including at least four bending element probes; the bending element detection element part of each bending element probe body is encapsulated in a probe module, and the tip of each bending element probe protrudes from the surface of the probe module to form an induction test end.

2. The device for detecting uniformity of fiber-stabilized soil according to claim 1, characterized in that: Two groups of bending element probe groups are respectively provided at a vertical bending element signal transmitting end (201) and a vertical bending element signal receiving end (202), comprising a first bending element probe group (2a) and a second bending element probe group (2b); wherein the four bending element probes of the first bending element probe group (2a) are arranged in a centrally symmetrical manner with an average interval of 90°, with the center of the circular bottom plate where the sensing test end is located as the center of the circle; and the four bending element probes of the second bending element probe group (2b) are also arranged in a centrally symmetrical manner with an average interval of 90°, with the center of the circular bottom plate where the sensing test end is located as the center of the circle. The distribution setting form is arranged in a centrally symmetrical manner; and after each probe, the center of the circular bottom plate where the sensing test end is located is taken as the center of the circle, so that the relative position of the second bending element probe group (2b) relative to the first bending element probe group (2a) is rotated and staggered by 45 degrees and arranged, so that the distribution form of a total of 8 bending element probes in the two groups of bending element probe groups on the same sensing test end surface forms a "M"-shaped structure; different groups of bending element probes at the same sensing test end have different distances from the center point of the circular bottom plate, so that two independent groups of shear wave velocities reflecting the transverse uniformity of the sample can be measured at one time.

3. The device for detecting uniformity of fiber-stabilized soil according to claim 2, characterized in that: The sizes of the bending element probes at the inductive test end are the same, and the radius of the circular base plate where the inductive test end is located is r; for the same circular base plate, the distance between the centers of the four bending element probes of the first bending element probe group (2a) and the center of the circular base plate is r / 3, and the four bending element probes of the first bending element probe group (2a) do not contact each other; the distance between the centers of the four bending element probes of the second bending element probe group (2b) and the center of the circular base plate is 2r / 3.

4. The device for detecting uniformity of fiber-stabilized soil according to claim 1, characterized in that: The four bending element probes of a transverse bending element probe group respectively provided at the transverse bending element signal transmitting end (301) and the transverse bending element signal receiving end (302) are evenly arranged in a straight line and are provided on a rectangular bottom plate where the induction test end is located, so that a group of shear wave velocities reflecting the vertical uniformity of the sample can be measured at one time.

5. The device for detecting uniformity of fiber-stabilized soil according to claim 1, characterized in that: The vertical support system includes a top crossbeam (103) and a stopper (101). Holes are opened near both ends of the top crossbeam (103) and support columns (110) are fitted into the holes. The top crossbeam (103) is horizontally mounted on the support columns (110). The top crossbeam (103) is adjusted in height along the vertical direction of the support columns (110). A stopper (101) is provided in the middle of the top crossbeam (103). The stopper (101) passes through the top crossbeam (103). The through hole in the middle allows the limiter (101) to be freely raised and lowered in the through hole along the direction of gravity. The limiter (101) is fixedly connected to the top of the vertical bending element signal transmitting end (201) through a connecting module to form an integrated downward pressing component. The upper half of the support column (110) is provided with a thread and equipped with a corresponding nut. The top crossbeam (103) and the support column (110) are connected via a vertical height adjustment nut (102) to adjust the position of the top crossbeam (103).

6. The device for detecting uniformity of fiber-stabilized soil according to claim 1, characterized in that: The transverse support system includes a transverse support rod (104), a transverse sleeve rod (105), a vertical support rod (106), and a vertical sleeve rod (107); The vertical sleeve rod (107) and the vertical support rod (106) are connected by a slide rail, and the vertical sleeve rod (107) and the vertical support rod (106) are fixedly connected by tightening a first limiting nut (111); the transverse sleeve rod (105) and the transverse support rod (104) are also connected by a slide rail, so that one end of the transverse support rod (104) is fixedly connected to the vertical support rod (106), and the transverse sleeve rod (105) and the transverse support rod (104) are fixedly connected by tightening a second limiting nut (108); the other end of the transverse support rod (104) is respectively supported and connected to a transverse bending element signal transmitting end (301) or a transverse bending element signal receiving end (302).

7. The device for detecting uniformity of fiber-stabilized soil according to claim 1, characterized in that: Each bending element probe comprises a detection element and a polycarbonate tip (404), and the detection element and the polycarbonate tip (404) are connected and fixed by an epoxy resin portion (403), so that the detection element and the polycarbonate tip (404) can be deformed in coordination, and the polycarbonate tip (404) enables the bending element probe group to be smoothly inserted into the surface layer of the sample and tightly combined with the sample.

8. The device for detecting uniformity of fiber-stabilized soil according to claim 1, characterized in that: The bending element probe group is positioned and installed through the holes reserved on the hollow cylindrical iron block, and the bending element probe is fixedly connected to the hollow cylindrical iron block. After the bending element probe is installed, epoxy resin is poured into the inner cavity of the hollow cylindrical iron block. After the epoxy resin is cured, an epoxy resin part (403) is formed, so that an integral structure is formed between the bending element probe body and the hollow cylindrical iron block.

9. The device for detecting uniformity of fiber-stabilized soil according to claim 1, characterized in that: By adjusting the relative position of the bending element probe and the sample to be tested, the shear wave velocity V at different angles θ and different heights h of the sample is measured. s , thereby obtaining the shear wave velocity V inside the sample s The three-dimensional distribution of .

10. The device for detecting uniformity of fiber-stabilized soil according to claim 1, characterized in that: By measuring the shear wave velocity V of the sample s , the shear wave velocity V is obtained by processing and calculation s The degree of uniformity of the sample is judged and evaluated by the range coefficient α. The calculation formula of the range coefficient α is: α=R / μ; R in the formula is the shear wave velocity V s The range of μ is the shear wave velocity V s The average value of The sample uniformity is evaluated according to the following standards: α<5% sample uniformity is excellent; 5%<α<10% sample uniformity is good; 10%<α<15% sample uniformity is fair; The sample uniformity is qualified if 10%<α<15%; the sample uniformity is unqualified if α>20%.

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