Debris flow abrasion test device, abrasion test, and abrasion assessment method for prevention and control projects

Abstract

The present invention discloses a debris flow abrasion test device, an abrasion test, and an abrasion assessment method for a prevention and control project. The debris flow abrasion test device of the present invention is an improvement of its own patented product. Its test block box assembly includes a test block box, a hole is opened on the outside of the box, and a centrally fixed annular part is provided. The annular part is threadedly connected to a fixing part and a placeholder part respectively. The former fixes the test block, and the latter blocks the sampling operation hole to ensure that the bottom of the box is flat. The test block box assembly also includes a stopper or a sample removal part. The debris flow abrasion test method of the present invention processes concrete test blocks, prepares debris flow abrasion materials, and adjusts the operation of the device according to the relevant design parameters of the abrasion test experiment to conduct a debris flow abrasion destructive force test. The debris flow abrasion assessment method of the present invention establishes a connection between two sets of field and indoor test data by key parameters to solve the conversion problem between indoor testing and on-site engineering feature assessment. The present invention can provide a scientific reference means for the design and maintenance of debris flow prevention and control projects.

Description

Technical Field

[0001] The present invention relates to a technology for measuring kinematic characteristics, and in particular to a device and method for measuring physical variables related to debris flow abrasion dynamics, as well as a method for evaluating abrasion characteristics of debris flow prevention and control projects based on the device and method. The present invention belongs to the fields of geological disaster monitoring and measurement technology, the technology of measuring material strength characteristics using mechanical stress, and the technology of geological disaster prevention and control technology. Background Art

[0002] Debris flows are one of the three major geological hazards in mountainous areas and are a key target for environmental management and ecological security efforts in mountainous areas. Debris flows are typically solid-liquid two-phase flows, with the solid phase consisting of coarse solid particles and the liquid phase primarily a mixture of fine solid particles and water. As a geological hazard, debris flows are characterized by high bulk density, wide particle size distribution, large particle sizes, multiphase coupling, and intense destructive power. The technical approach to debris flow prevention in mountainous areas is "stabilization, interception, and drainage," specifically achieved through the construction of various debris flow prevention projects. Traditional debris flow prevention projects are geotechnical measures, specifically concrete buildings / structures. Although recent engineering designs have focused on integrating ecological measures into prevention projects and promoting their integration with geotechnical measures, concrete structures remain the core component of various prevention projects. With the rise of environmental and ecological management concepts and the exposure of some shortcomings of purely geotechnical measures in operation, the stability and safety of the concrete components of various debris flow prevention projects are crucial for the overall stability and safety of the entire project.

[0003] Debris flow control structures are often damaged by abrasion due to the collision and rolling friction of coarse debris particles in debris flows. Many types of debris flow control structures, including overflow dams, overflow channel linings, and gate piers, are subject to debris flow abrasion damage during operation. Among these, abrasion and slope damage in key areas such as the dam crest, drainage channel bottom, and sidewalls are of particular concern. Assessing the level of debris flow abrasion in key geotechnical areas, both locally and throughout the project, is crucial to ensuring the long-term safe operation and performance of the project structures, and is also crucial to the safety of the protected areas.

[0004] An effective means of measuring and evaluating the abrasion characteristics of debris flow prevention projects is to use indoor abrasion test equipment and methods. The most commonly used indoor abrasion tests include underwater abrasion method (ASTM C1138), road abrasion method, Abrasion methods and some improved non-standard abrasion methods. These technologies are derived from the field of river dynamics research. The fluid characteristics considered in the test are quite different from the solid-liquid two-phase flow characteristics of debris flows. The corresponding test equipment and methods are not suitable for debris flow abrasion testing. For example, the high rotation speed (1200rpm) used in the underwater abrasion test is significantly different from the actual flow rate of debris flows (usually less than 10m / s). Due to the action of centrifugal force, the center position of the concrete sample usually does not produce abrasion damage, which is inconsistent with the actual characteristics of debris flow movement and is therefore not suitable for debris flow abrasion testing. Similarly, existing conventional abrasion equipment is not equipped with the characteristics of debris flows such as high bulk density, wide and huge particle grading, and multi-phase mixing, and cannot support the implementation of debris flow abrasion testing.

[0005] The applicant's dual-axis roller wear resistance testing device and method (ZL2021109404941) developed to simulate channel cross-sectional morphology can accurately simulate the damage of concrete to debris flow abrasion under solid-liquid coupling conditions. The abrasion morphology obtained in the abrasion test is very similar to that in actual engineering scenarios, solving the technical problems of indoor debris flow abrasion testing. However, this technology still has two unresolved issues when it comes to assessing the actual abrasion damage in debris flow prevention and control projects. First, the testing device is not perfect. The concrete test block fixing structure and operation used in this device, such as the pre-embedded steel nail sample and surface steel wire fixing method, are cumbersome and affect the test efficiency of the test process. In addition, because small debris flow particles can be embedded between the sample and the instrument, the installation and removal of the concrete test block is very difficult, significantly limiting the test efficiency. Furthermore, the pre-embedded steel nail sample increases the difficulty of sample preparation, and the surface steel wire fixing method can be affected by the impact of the debris flow during the abrasion process, causing the steel wire to break. Due to the blocking effect of the surface steel wire, the abrasion of the concrete under the steel wire is also affected, affecting the test accuracy. Second, the technology has not yet solved the problem of conversion from indoor abrasion test data analysis to on-site engineering abrasion feature assessment, that is, it has not yet solved the technical problem of on-site assessment of the degree of abrasion damage in actual prevention and control projects. Summary of the Invention

[0006] The purpose of the present invention is to address the deficiencies of the existing technology and provide a debris flow abrasion testing technology and a method for evaluating the degree of abrasion damage in prevention and control projects.

[0007] To achieve the above objectives, the present invention first provides a technical solution with an improved design based on the applicant's dual-axis rolling wear resistance testing device that can simulate the channel cross-sectional morphology (ZL 2021109404941).

[0008] A debris flow abrasion testing device comprises a motor support base, a dual-axis motor, a disc device, and a test block box assembly; the characteristics are that: the test block box assembly main body is a test block box, the test block box is an open box, the box bottom is opened, the outer side surface of the hole is fixed with a ring part, the inner hole of the ring part has an internal thread and is aligned with the hole; the opposite side walls of the box are symmetrically opened, the outer side surface of the hole is fixed with a ring part, the inner hole of the ring part has an internal thread and is aligned with the hole; the fixing part passes through the ring part on the side wall of the test block box from the outside to the inside and is threadedly connected to the inner hole, fixing the test block in the test block box from the relative direction; the placeholder passes through the ring part at the bottom of the test block box from the outside to the inside and is threadedly connected to the inner hole; the stopper is detachably connected to the outer part of the placeholder to prevent the placeholder from screwing into the box; the test block box assembly also includes a spacer, which is lined between the test block and the test block box.

[0009] The improved debris flow abrasion test device described above is based on the original design, with a redesigned test block box assembly (i.e., sample box 24 in the original device). The original design failed to adequately consider the installation and removal procedures for concrete test blocks during abrasion testing, resulting in two extremely cumbersome steps in the experimental test. First, the test block preparation requires pre-embedded circular steel nails at specific locations within the test block, ensuring that the two nails are level and aligned. Otherwise, the test block installation may experience unbalanced tightening forces at both ends, resulting in uneven wear surfaces and poor abrasion contact. This requires specialized sample preparation molds. Second, when the test block is recovered after abrasion, small solid particles clog the gaps within the box, making removal of the test block difficult and requiring forced removal. To specifically address the aforementioned deficiencies of the original device, the present invention redesigns the test block box assembly. To address the first drawback, the present device analyzes the direction and magnitude of the forces acting on the test block during abrasion, improving the force used to secure the test block from the original threaded connection tension to compression. This eliminates the need for pre-embedded threaded tie rods, simplifying the test block structure and sample preparation process. To address the second drawback, this device features an operating hole in the bottom of the box, which is then sealed with a spacer to keep the bottom flat. When retrieving and removing the test block, a screw is threaded through the operating hole into the box, using a tiny screw to push the test block out of the box more easily.

[0010] Another solution for the operating hole and the placeholder at the bottom of the box of the above-mentioned improved debris flow abrasion testing device is that there is no stop piece to prevent the placeholder from spirally advancing, and there is an independent sample removal piece; the sample removal piece can replace the placeholder and be threadedly connected to the test block box, and the sample removal piece can be screwed into the test block box for a longer distance than the placeholder.

[0011] Utilizing the improved debris flow abrasion testing device of the present invention, the present invention also provides a debris flow abrasion testing method, and the technical solution is as follows.

[0012] A debris flow abrasion testing method is characterized by being implemented using the above-mentioned debris flow abrasion testing device, comprising:

[0013] Test block preparation: Prefabricate concrete test blocks that meet the test block box specifications based on the designed test block characteristic parameters of the abrasion test experiment, and perform standard curing to the designed age; measure and record the original indicators of the test blocks;

[0014] Test block loading operation: Take the test block box, install the placeholder, screw the placeholder in until its front end is flush with the bottom of the test block box, and the limit placeholder prevents it from being screwed in further. The bottom of the test block box is lined with spacers; put the test block in, and line the spacers between the test block and the inner wall of the test block box; install the fixing parts, screwing the fixed test block in from both sides; install the test block box on the test part of the device;

[0015] Abrasive material sample preparation and loading operation: Prepare debris flow abrasive material according to the physical characteristic parameters of the debris flow abrasive material designed for the abrasion test experiment and load it into the disc device;

[0016] Abrasion operation: adjust the motor working parameters according to the design of the debris flow abrasive material movement characteristic parameters of the abrasion test experiment, start the motor, reach the design abrasion time of the abrasion test experiment, and then turn off the motor;

[0017] Test block recovery operation: remove the test block box from the test section, withdraw the fixings, remove the spacers around the test block, remove the placeholder limiter and continue to screw the placeholder into the test block box until the test block is lifted up, or replace the placeholder with the sample removal part and screw it into the test block box until the test block is lifted up, remove the test block, and recycle it according to standard operations;

[0018] Abrasion data collection operation: measure and record the indicators of the test block after abrasion;

[0019] Analysis of debris flow abrasion characteristics: Comprehensively analyze and evaluate the debris flow abrasion characteristics based on the original index values ​​of the test blocks, the index values ​​after abrasion, the physical characteristic parameters of the designed debris flow abrasive materials, and the motion characteristic parameters of the designed debris flow abrasive materials.

[0020] The debris flow abrasion test method involves processing concrete test blocks, preparing debris flow abrasive materials, and adjusting device operation according to the relevant design parameters of the abrasion test experiment to conduct debris flow abrasion damage testing. Before abrasion, the original test block indicators are measured and recorded, such as the physical specifications, mass, volume, 3D scanning modeling, scanning electron microscopy imaging of the abrasion surface, and high-definition digital imaging of the abrasion surface. After the experiment, the post-abrasion indicators of the test block are measured and recorded. Post-abrasion indicators generally include the corresponding items of the original indicators, as well as indicators that specifically describe the characteristics of debris flow abrasion damage.

[0021] In the abrasive material sample preparation and loading operation of the above test method, the raw materials for preparing debris flow abrasive materials include abrasive particles, soil, and water. The amounts of the three raw materials are calculated according to formulas 1 to 5, that is, the raw water mass M w (kg), raw material soil mass M s (kg), mass of raw material abrasive particles M p (kg).

[0022]

[0023] M sd =V0×C v ×ρ s Formula 2

[0024] M w =V0×(1-C v )×ρ w Formula 3

[0025]

[0026] M p =M sd -M s Formula 5

[0027] In the formula, the physical characteristic parameters of the designed debris flow abrasive material belonging to the abrasion test experimental design parameters are: the volume content of solid phase particles of the debris flow abrasive material C v (%), density of debris flow abrasive material ρ0 (kg / m 3 ), raw water density ρ w (kg / m 3 ), solid phase particle density ρ s (kg / m 3 ), volume of debris flow abrasive material V0 (m 3 ), soil-to-water ratio in debris flow abrasive materials The mass of solid particles of debris flow abrasive material M sd To calculate the intermediate amount.

[0028] In the abrasion operation of the above test method, the motor operating parameters that need to be designed mainly include the motor inverter frequency f (Hz), which is designed according to Equations 6 to 8.

[0029]

[0030] u=2×π×n×r Formula 8

[0031] Wherein, the characteristic parameter of the designed debris flow abrasive material movement, which belongs to the design parameters of the abrasion test experiment, is the abrasion velocity u (m / s) of the debris flow abrasive material; the operating parameters of the device are the motor synchronous speed N (rps), the motor speed n (rps), the number of motor pole pairs p, the motor slip rate s, and the rotation radius r (m) of the disc device.

[0032] The ultimate goal of the two technical solutions provided by this invention, a debris flow abrasion testing device and a debris flow abrasion testing method, is to address the problem of assessing the degree of debris flow abrasion damage to various concrete structures during actual debris flow prevention and control projects. This invention also provides a method for assessing the degree of abrasion damage in debris flow prevention and control projects, the technical solution of which is as follows.

[0033] A method for evaluating the amount of abrasion in debris flow prevention and control projects, characterized by being implemented using the above-mentioned debris flow abrasion testing method, comprising:

[0034] First, conduct field investigations to obtain field data related to debris flow prevention and control projects;

[0035] Secondly, a debris flow abrasion test experiment is set up to determine indoor test data, which includes abrasion test experiment design parameters, debris flow abrasion test device operating parameters, and abrasion test measurement data;

[0036] Finally, the field data and indoor test data were used to evaluate the abrasion amount E of debris flow prevention engineering.

[0037]

[0038] Where, E is the abrasion amount of debris flow prevention project, unit is kg,

[0039] k - test abrasion coefficient, unit: kg·h -1 ·m -2 , debris flow abrasion test data confirmed,

[0040] V s - Volume content of solid particles in debris flow at the scene, %, field data,

[0041] ρ - on-site debris flow density, kg / m 3 , field data,

[0042] D s - Average particle size of solid phase particles in debris flow at the site, in m, determined by field data,

[0043] u s - On-site debris flow velocity, in m / s, determined by field data,

[0044] C v - Volume content of solid particles in debris flow abrasive materials, %, determined by debris flow abrasion test data,

[0045] ρ0 - density of debris flow abrasive material, kg / m 3 , debris flow abrasion test data confirmed,

[0046] D0 - average particle size of solid phase particles of debris flow abrasive material, unit is m, determined by debris flow abrasion test data,

[0047] u is the abrasion velocity of debris flow abrasive materials, in m / s, determined by debris flow abrasion test data; A is the abrasion area of ​​the engineering structure, in m 2 , field data confirmed,

[0048] t - duration of abrasion, in hours, determined by field data.

[0049] The basic principle of the above-mentioned method for evaluating the abrasion amount of debris flow prevention and control projects is to evaluate and select indicators that can effectively measure the contribution rate of abrasion damage from different debris flow physical characteristics and motion characteristic parameters based on a large amount of previous field measurements and indoor experimental test data as calculation variables, and construct a mathematical calculation model to solve the mathematical model method for evaluating the abrasion amount of debris flow prevention and control projects using field investigation and experimental test data.

[0050] The above-mentioned debris flow prevention project abrasion evaluation method, the test abrasion coefficient k represents the abrasion mass loss per unit time and per unit area. Based on the debris flow abrasion test data obtained by the debris flow abrasion test method of the present invention, the test abrasion coefficient k can be expressed according to formula 10, where A r - Test abrasion rate (kg / h), A0 - test block bearing surface area (m 2 ), all are indoor test data.

[0051]

[0052] The field investigation referred to in this technology includes various geological surveys, reconnaissance, mapping, and measurement work at the flash flood and debris flow channel where the project is located, as well as existing simulation experiments, testing experiments, observation experiments, and analysis experiments in the field, as well as the acquisition of historical disaster records, relevant technical specifications, and empirical methods and data acquisition for reference. The data obtained from the field investigation is collectively referred to as the field data of this technical solution.

[0053] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) It provides an improved debris flow abrasion test device with an optimized test block box assembly structure. The product solves the problem of difficulty in test block installation and recovery caused by small particles of debris flow abrasive material embedded in the gap between the test block and the device during the abrasion test, and can simplify a series of operations such as sample preparation, sample loading, and recovery around the test block, and enable these operations to be fully modeled and streamlined, thereby increasing the efficiency of abrasion testing and enabling the device to better meet the needs of debris flow abrasion testing. (2) It provides a debris flow abrasion test method. (3) Using the debris flow abrasion test method of the present invention as a means, the present invention establishes a field structure abrasion prediction model constructed by connecting key parameters between two sets of data: engineering field data (i.e., field data related to debris flow prevention and control projects) and laboratory data (i.e., indoor test data), solving the conversion problem from indoor abrasion test data analysis to field engineering abrasion feature evaluation, and specifically provides a debris flow prevention and control project abrasion evaluation method. By utilizing the evaluation method of the present invention, the technical solution for evaluating the degree of abrasion damage in debris flow prevention and control projects can be transformed from the current combination of on-site measurement and empirical judgment to a combination of on-site measurement and indoor experimental means, thereby greatly enhancing the scientific nature and reliability of the evaluation, thereby improving the utilization value of the evaluation data and enabling it to be more effectively used as a scientific indicator for the design and maintenance of debris flow prevention and control projects. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 This is a schematic diagram of one installation method of the test block box on the disc device.

[0055] Figure 2 This is a schematic diagram of the external structure of the test block box assembly (A and B show two types of fixing parts structures).

[0056] Figure 3 It is a schematic diagram of the cross-sectional structure of the test block box assembly.

[0057] Figure 4 It is a schematic cross-sectional structure diagram of the test block box assembly of Example 2.

[0058] The numbers in the accompanying drawings are: 1 test block box assembly; 11 test block box; 111 hole; 112 ring member; 12 fixing member; 13 placeholder; 14 stop member; 15 sample removal member; 16 spacer; 2 test block; 3 disc device. DETAILED DESCRIPTION

[0059] The preferred embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0060] Example 1

[0061] like Figures 1 to 3 As shown in FIG. 1 , a debris flow abrasion testing device is manufactured.

[0062] This debris flow abrasion test device is an improved product of the existing dual-axis roller wear resistance test device (ZL 2021109404941) that can simulate the cross-sectional shape of a channel. The structure of the original device is the same as that of the original device and will not be described in detail here. This specific embodiment focuses on the improvements.

[0063] Figure 1 This is a schematic diagram of one installation method of the test block box on the disc device; Figure 2 Schematic diagram of the external structure of the test block box assembly 1 (A and B show two fixing parts structures); Figure 3 2 is a schematic diagram of the cross-sectional structure of the test block box assembly 1.

[0064] The debris flow abrasion testing device includes a motor support base, a dual-axis motor, a disc device, and a test block box assembly 1. The test block box assembly 1 mainly comprises a test block box 11. The test block box 11 is an open box with a hole 111 at the bottom. An annular member 112 is fixed to the outer side of the hole 111. The inner hole of the annular member 112 has an internal thread and is aligned with the hole 111. The opposite side walls of the box also have symmetrical holes 111. An annular member 112 is fixed to the outer side of the hole 111. The inner hole of the annular member 112 has an internal thread and is aligned with the hole 111. The fixing member 12 passes through the annular member 112 on the side wall of the test block box 11 from the outside to the inside and is threadedly connected to the inner hole, fixing the test block 2 in the test block box 11 from the relative direction; the placeholder 13 passes through the annular member 112 on the bottom of the test block box 11 from the outside to the inside and is threadedly connected to the inner hole; the stop member 14 is detachably connected to the outer part of the box of the placeholder 13, which can prevent the placeholder 13 from being screwed into the box; the test block box assembly 1 also includes a spacer 16, which is lined between the test block 2 and the test block box 11.

[0065] In this embodiment, the spacer 16 is made of rubber.

[0066] Example 2

[0067] like Figure 4 As shown in the figure, a debris flow abrasion testing device is manufactured. The same points as those in the first embodiment are not repeated here.

[0068] Figure 4 It is a schematic cross-sectional structure diagram of the test block box assembly 1 of the second embodiment.

[0069] The test block box assembly 1 does not have a stopper 14, but has an independent sample removal piece 15; the sample removal piece 15 can replace the placeholder 13 and be threadedly connected to the test block box 11. The sample removal piece 15 can be screwed into the test block box 11 for a longer distance than the placeholder 13.

[0070] In this design, placeholder 13 serves only as a "placeholder," ensuring a flat bottom surface. To remove the test block 2, first withdraw placeholder 13 from the access hole (i.e., hole 111), then install sample removal member 15. Sample removal member 15 spirals into the box to eject the test block. This approach shortens placeholder 13 and simplifies the design of the mating structure between stopper 14 and placeholder 13.

[0071] In this embodiment, since the mating structure of the stopper 14 and the placeholder 13 is omitted, a large number of existing parts can be used for processing and forming. For example, the ring member 112 is a common nut, and the fixing member 12, placeholder 13, and sample removal member 15 are all ordinary bolts. Thus, by utilizing the wide variety of readily available nut and bolt specifications, the test block box assembly 1 that meets the test design requirements (primarily the specifications of the operating hole and the fixing member 12) can be quickly and cost-effectively manufactured.

[0072] Generally, the length of the screw of the placeholder 13 bolt is L 13 Equal to the thickness of the nut at the installation position, the screw length L of the sample 15 bolt 15 Greater than the thickness of the nut at the installation position. In this embodiment, the screw length L of the bolt of the demolition piece 15 is 15 Equal to the sum of the thickness of the mounting nut and the thickness of test block 2.

[0073] Example 3

[0074] The technical solution of the present invention is used to evaluate the abrasion amount of debris flow prevention and control projects.

[0075] 1. On-site investigation of debris flow prevention projects

[0076] Field investigation was conducted to obtain field data of debris flow prevention and control projects, see Table 1.

[0077] Table 1 Field data of debris flow prevention project

[0078]

[0079]

[0080] 2. Debris flow abrasion test experiment

[0081] Set up a debris flow abrasion test experiment and obtain debris flow abrasion test data.

[0082] Table 2 Experimental data of debris flow abrasion test

[0083]

[0084] 2.1 Test block preparation

[0085] In this embodiment, the debris flow abrasion testing device of Example 2 is used.

[0086] The specifications of the test block box assembly 1 and the test block 2 are shown in Table 3.

[0087] Table 1 Specifications of test block box assembly and concrete test block (mm)

[0088]

[0089] Concrete specimen 2 was processed according to the designed specimen characteristic parameters (Table 2) of the abrasion test experiment. After processing, the specimen characteristics met the requirements of compressive strength of 48.0±2.9 (MPa), flexural strength of 10.84±0.38 (MPa), and splitting tensile strength of 6.75±1.01 MPa. The wear surface area of ​​specimen 2 is A0 = 0.16*0.04*0.04 = 2.56*10 -4 m 2 .

[0090] Test block 2 was cured to the design age under standard conditions. The original indicators of test block 2 were measured and recorded (Table 5).

[0091] Specimen saturation density ρ sat Yes, after the specimen 2 reaches the designed curing age, immerse it in water for at least 48 hours until its mass stabilizes; take it out of the water, wipe off the surface moisture, and use a balance with an accuracy of 0.01g to record the mass (M b ); Use a micrometer with an accuracy of 0.001mm to measure the external dimensions (length L s , width W s , height H s ); calculate its saturation density (ρ sat ).

[0092] 2.2 Test block loading

[0093] Take the test block box 11, install and tighten the bolts of the placeholder 13. At this time, the front end of the bolt of the placeholder 13 is flush with the bottom surface of the test block box 11, and the limit placeholder 13 prevents it from continuing to screw in. The bottom surface of the test block box 11 is lined with a spacer 16; put in the test block 2, and line the spacer 16 between the test block 2 and the inner wall of the test block box 11; install and tighten the bolts of the fixing part 12, and screw in the fixed test block 2 from both sides; install the test block box 11 on the test part of the device.

[0094] 2.3 Abrasive material sample preparation and loading operations

[0095] Experimental design parameters included the design of test block characteristics, the design of debris flow abrasive material physical characteristics, and the design of debris flow abrasive material motion characteristics. The raw materials for the debris flow abrasive material preparation included abrasive particles, soil, and water (Table 2). A total of 10 test groups were designed. The abrasive material parameters for each group were calculated using Equations 1 to 5 and are shown in Table 4.

[0096] Table 4 Abrasive material ratio design parameters

[0097]

[0098]

[0099] 2.4 Abrasive operation

[0100] For each test, the prepared debris flow abrasive material was loaded into the disc device. Based on the designed debris flow motion characteristic parameters for the abrasion test, the motor inverter frequency f was calculated for each test using Equations 6-8, and the motor operating parameters were adjusted. The motor was started, and after the designed abrasion time t was reached, the motor was turned off. During the abrasion process, the debris flow abrasion test device or the test portion of the device was covered with sound-absorbing material.

[0101] To save space, the following steps only list some of the test data in Table 4.

[0102] Table 5 Parameters related to abrasion operation

[0103] serial number f(Hz) p s r(m) u(m / s) n(rps) t(h) 1 1.9 2 0 0.5 3 0.96 24 3 2.5 2 0 0.5 4 1.27 24 4 3.2 2 0 0.5 5 1.59 24

[0104] The present invention designed different debris flow abrasion test experiments and compared the optimal abrasion test parameters based on the experimental data of each group. The results showed that the debris flow abrasion test conditions for obtaining the best abrasion effect were: the density of the debris flow abrasive material ρ0 = 1900 kg / m 3 , the abrasive material abrasion speed of debris flow is u=5m / s, and the raw material abrasive particles are steel balls with a particle size of 20mm.

[0105] 2.5 Test block recovery

[0106] After the test is completed, remove the test block box 11 from the test part, remove the bolts of the fixing part 12, remove the spacers 16 around the test block 2, remove the bolts of the placeholder 13, replace and install the bolts of the sample removal part 15, screw the bolts of the sample removal part 15 into the test block box 11 to lift the test block 2; remove the test block (2) and recycle it according to standard operations.

[0107] 2.6 Abrasion data acquisition operation

[0108] Measure and record the indicators of test block 2 after abrasion (Table 5).

[0109] The simplest way to collect the external specification data of the test block 2 (especially the grinding surface) is to use 3D scanning modeling. By comparing the models before and after the test, the surface morphology of the grinding surface and the changes in related physical indicators can be accurately measured.

[0110] In addition to this 3D modeling method, it is difficult to measure the height value of the test block 2 after the test using traditional methods. To this end, the present invention provides a measurement method for measuring the height change of the test block 2 by traditional measurement means. Specifically: After the test block is prepared and the original indicators are measured, a marking line is used on the wear surface in advance (such as using a waterproof marker), for example, seven straight lines are marked along the long axis of the test block 2 at intervals of 20mm, 40mm, 60mm, 80mm, 100mm, 120mm, and 140mm. After abrasion, the critical abrasion sites can be quickly located by marking the breakpoint position and breakpoint diameter on the line. Measuring the height of the critical abrasion site (H a ) and analyze the height change before and after abrasion, and can measure the single point abrasion depth (ΔH).

[0111] 2.7 Analysis of debris flow abrasion characteristics

[0112] The debris flow erosion characteristics are analyzed and evaluated based on the original index values ​​of test block 2, the index values ​​after abrasion, the designed debris flow physical characteristic parameters, and the designed debris flow motion characteristic parameters.

[0113] Table 6 Index values ​​of test blocks before and after abrasion

[0114] quality high Displacement volume Saturation density Raw indicators <![CDATA[M b ]]> <![CDATA[H s ]]> / <![CDATA[ρ sat ]]> Post-abrasion indicators <![CDATA[M a ]]> <![CDATA[H a ]]> <![CDATA[V drain ]]> /

[0115] Abrasive mass loss, Δm=M b -M a

[0116] Test abrasion rate, A r =Δm / t

[0117] Single point abrasion depth, ΔH=H s -H a

[0118] Average abrasion depth, or

[0119] Test the abrasion coefficient k according to formula 10.

[0120]

[0121] To save space, the description of other abrasion feature analysis contents is omitted here.

[0122] 3. Evaluate the abrasion volume E of debris flow prevention projects

[0123] The abrasion loss E of debris flow prevention project was calculated according to Equations 9 and 10 using the field data and indoor test data of debris flow prevention project (Table 7).

[0124] Table 7 Evaluation data on the degree of abrasion damage in debris flow prevention and control projects

[0125]

[0126] 4. Verification

[0127] Taking the local structure of the prevention and control project as an example, the calculated data of the method of the present invention is compared with the measured data, which shows that the accuracy of the abrasion amount calculated by the method of the present invention is within the acceptable range of actual engineering.

Claims

1. A debris flow abrasion testing device, comprising a motor support base, a dual-axis motor, a disc device, and a test block box assembly (1); characterized in that: The main body of the test block box assembly (1) is a test block box (11), which is an open box with a hole (111) at the bottom. An annular member (112) is fixed on the outer side of the hole (111), and the inner hole of the annular member (112) has an internal thread and is aligned with the hole (111); holes (111) are symmetrically opened on opposite side walls of the box, and an annular member (112) is fixed on the outer side of the hole (111), and the inner hole of the annular member (112) has an internal thread and is aligned with the hole (111); The fixing member (12) passes through the annular member (112) on the side wall of the test block box (11) from the outside to the inside and is threadedly connected to the inner hole, thereby fixing the test block (2) in the test block box (11) from the opposite direction; The placeholder (13) passes through the annular member (112) at the bottom of the test block box (11) from the outside to the inside and is threadedly connected to the inner hole; the stopper (14) is detachably connected to the outer part of the placeholder (13) to prevent the placeholder (13) from being screwed into the box; the test block box assembly (1) also includes a spacer (16) which is laid between the test block (2) and the test block box (11).

2. The debris flow abrasion testing device according to claim 1, characterized in that: There is no stopper (14); there is an independent sample removal piece (15), which can replace the placeholder (13) and be threadedly connected to the test block box (11). The sample removal piece (15) can be screwed into the test block box (11) for a longer distance than the placeholder (13).

3. The debris flow abrasion testing device according to claim 2, characterized in that: The annular member (112) is a nut, and the fixing member (12), the place-occupying member (13), and the sample removal member (15) are all bolts.

4. The debris flow abrasion testing device according to claim 3, characterized in that: The screw length L of the bolt of the spacer (13) 13 Equal to the thickness of the nut of the mounting ring (112), the length of the screw of the bolt of the demolition piece (15) 14 It is equal to the sum of the thickness of the nut of the mounting ring member (112) and the thickness of the test block (2).

5. Debris flow abrasion test method, characterized by: The method is implemented by using the debris flow abrasion testing device according to any one of claims 1 to 4, comprising: Sample preparation operation of the test block (2): prefabricate a concrete test block (2) that meets the specifications of the test block box (11) according to the characteristic parameters of the designed test block of the abrasion test experiment, and perform standard curing to the designed age; measure and record the original indicators of the test block (2); The test block (2) sample loading operation is as follows: take the test block box (11), install the placeholder (13), screw the placeholder (13) in until its front end is flush with the bottom surface of the test block box (11), and the limit placeholder (13) prevents it from being screwed in further. The bottom surface of the test block box (11) is lined with a spacer (16); put the test block (2) in, and line the spacer (16) between the test block (2) and the inner wall of the test block box (11); install the fixing member (12), and screw the fixed test block (2) in from both sides; install the test block box (11) on the test part of the device; Abrasive material sample preparation and loading operation: Prepare debris flow abrasive material according to the designed debris flow physical characteristic parameters of the abrasion test experiment and load it into the disc device; Abrasion operation: adjust the motor operating parameters according to the designed debris flow motion characteristic parameters of the abrasion test experiment, start the motor, and turn off the motor when the designed abrasion time t of the abrasion test experiment is reached; Test block (2) recovery operation: remove the test block box (11) from the test part, withdraw the fixing part (12), take out the spacers (16) around the test block (2), remove the position limiter (13) and continue to rotate the placeholder (13) into the test block box (11) until the test block (2) is lifted up, or replace the placeholder (13) with the sample removal part (15) and rotate it into the test block box (11) until the test block (2) is lifted up, take out the test block (2), and recycle it according to standard operation; Abrasion data collection operation: measure and record the test block (2) after abrasion; Analysis of debris flow abrasion characteristics: Comprehensively analyze and evaluate the debris flow abrasion characteristics by using the original index value of the test block (2), the index value after abrasion, the designed debris flow physical characteristic parameters, and the designed debris flow motion characteristic parameters.

6. The abrasion testing method according to claim 5, characterized in that: In the abrasive material sample preparation and loading operation, the raw materials for preparing the debris flow abrasive material include abrasive particles, soil, and water. The amounts of the three raw materials are calculated according to Formulas 1 to 5. M sd =V0×C v ×ρ s Formula 2 M w =V0×(1-C v )×ρ w Formula 3 M p =M sd -M s Formula 5 Where C v - Volume content of solid particles in debris flow abrasive materials, %, abrasion test experimental design parameters, ρ0 - density of debris flow abrasive material, unit: kg / m 3 , abrasion test experimental design parameters, ρ w - Density of raw water, unit: kg / m 3 ,constant, ρ s - Solid phase particle density, unit: kg / m 3 , abrasion test experimental design parameters, M sd - Mass of solid particles of debris flow abrasive material, kg, V0 - volume of debris flow abrasive material, m 3 , abrasion test experimental design parameters, - Soil-water ratio in debris flow abrasive material, %, abrasion test experimental design parameters, M w -Mass of raw water, kg, M s -Mass of raw soil, kg, M p -Mass of raw material abrasive particles, kg.

7. The abrasion testing method according to claim 6, characterized in that: The motor operating parameters include the motor inverter frequency f (Hz), which is designed according to equations 6 to 8. u=2×π×n×r Formula 8 Where, f is the frequency of the motor inverter, in Hz. N - motor synchronous speed, unit rps, debris flow abrasion test device working parameters, n - motor speed, unit rps, debris flow abrasion test device working parameters, p - number of motor pole pairs, working parameters of debris flow abrasion test device, s - motor slip rate, debris flow abrasion test device working parameters, u - abrasion velocity of debris flow abrasive material, unit m / s, abrasion test experimental design parameters, r - the rotation radius of the disc device, in m, is the working parameter of the debris flow abrasion test device.

8. A method for assessing the amount of abrasion in debris flow prevention projects, characterized by: The method is implemented by using the debris flow abrasion testing method according to claim 6 or 7, comprising: First, conduct field investigations to obtain field data related to debris flow prevention and control projects; Secondly, a debris flow abrasion test experiment is set up to determine indoor test data, which includes abrasion test experiment design parameters, debris flow abrasion test device operating parameters, and abrasion test measurement data; Finally, the field data and indoor test data were used to evaluate the abrasion amount E of debris flow prevention engineering. Where, E is the abrasion amount of debris flow prevention project, unit is kg, k - test abrasion coefficient, unit: kg·h -1 ·m -2 , indoor test data confirmed, V s - Volume content of solid particles in debris flow at the scene, %, field data, ρ - on-site debris flow density, kg / m 3 , field data, D s - Average particle size of solid phase particles in debris flow at the site, in m, determined by field data, u s - On-site debris flow velocity, in m / s, determined by field data, C v - Volume content of solid particles in debris flow abrasive materials, %, determined by indoor test data, ρ0 - density of debris flow abrasive material, kg / m 3 , indoor test data confirmed, D0 - average particle size of solid phase particles of debris flow abrasive materials, unit is m, determined by indoor test data, u - the abrasive velocity of debris flow abrasive materials, unit is m / s, determined by indoor test data, A - the abrasion area of ​​the engineering structure, unit: m 2 , field data confirmed, t - duration of abrasion, in hours, determined by field data.

9. The method for evaluating the amount of abrasion in debris flow prevention and control projects according to claim 8, characterized in that: The test abrasion coefficient k is expressed according to formula 10: Where, k is the test abrasion coefficient, unit: kg·h -1 ·m -2 , A r - Test abrasion rate, unit kg / h, determined by indoor test data, A0 - grinding surface area of ​​test block, unit: m 2 , confirmed by indoor test data.

10. The method for evaluating the amount of abrasion in debris flow prevention and control projects according to claim 8, characterized in that: The debris flow abrasion test experiment was built, and the density of the debris flow abrasive material was ρ0 = 1900 kg / m 3 , the abrasive material abrasion speed u = 5m / s, the raw material abrasive particles are steel balls with a particle size of 20mm.

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