Earth and rockfill dam damming material consolidation test sample preparation device and sample preparation method

Abstract

The invention discloses an earth and rockfill dam damming material consolidation test sample preparation device and a sample preparation method, the earth and rockfill dam damming material consolidation test sample preparation device comprises a floating ring type consolidation container, a floating ring is arranged in the floating ring type consolidation container, and after the floating ring is filled with a sample, the sample is prepared through the counter-force floating ring of a counter-force device or the sample is prepared through excitation of a double-machine frequency modulation vibrator; wherein the counter-force static pressure sample forming method does not raise dust in the sample preparation process, avoids particle crushing to a greater extent, and is suitable for damming materials which have low sample preparation density requirements in an indoor consolidation test and are easy to form samples; the frequency modulator is additionally arranged on the double vibration motors in the excitation sample forming method of the double-machine frequency modulation vibrator, so that the vibration frequency of the double-machine frequency modulation vibrator can be adjusted in the sample preparation process, the condition of over-vibration or under-vibration of a sample is avoided, and the excitation sample forming method is suitable for damming materials which have high sample preparation density requirements and are not easy to form in an indoor consolidation test.

Description

Technical Field

[0001] The invention belongs to the technical field of geotechnical tests for water conservancy and hydropower engineering, and in particular relates to a sample preparation device for a consolidation test of earth-rock dam building materials, and also relates to a sample preparation method for a consolidation test of earth-rock dam building materials. Background Art

[0002] Earth-rock dams are widely used in the construction of water conservancy and hydropower projects. With the improvement of construction technology, the height of earth-rock dams has been significantly improved, the rolling process has become more and more perfect, and the on-site rolling density of dam materials has been continuously improved. It is self-evident that it is necessary to study the mechanical properties of dam materials through indoor tests. Among them, the consolidation test can determine the relationship between the porosity and pressure of dam materials, and calculate the compression coefficient, compression index, volume compression coefficient, compression modulus, consolidation coefficient and initial consolidation pressure of dam materials, which is of great significance for guiding the construction of earth-rock dam projects.

[0003] When conducting consolidation tests on dam-building materials in a high-density state, due to the large size of the consolidation test specimens and the limitations of indoor space and technology, the conventional sample preparation method is often faced with the problem that the dam-building materials cannot reach a high-density state, and even the sample preparation density is far lower than the set density; on the other hand, the conventional sample preparation method will generate a large amount of dust during the sample preparation process, thereby polluting the indoor environment and endangering the health of the test personnel. When conducting consolidation tests on dam-building materials in a low-density state, the conventional sample preparation method often has the problem of sample over-vibration, resulting in an increase in the sample density, causing serious deviations in the test results. When the sample composition is soft rock dam-building material, the conventional sample preparation method is very likely to cause the coarse particles in the sample to be broken during the sample preparation process, changing the test gradation of the sample, and also causing serious deviations in the test results. The above problems have not yet been effectively solved in this field, and the present invention starts from the root of the test itself and solves the above problems through a new sample preparation method. Summary of the invention

[0004] The purpose of the present invention is to provide a sample preparation device for a consolidation test of earth-rock dam building materials, which solves the problem that the existing sample preparation methods often have sample over-vibration or coarse particles are easily broken during the sample preparation process, resulting in serious deviations in test results.

[0005] The present invention also aims to provide a sample preparation method for a consolidation test of earth-rock dam construction materials.

[0006] The first technical solution adopted by the present invention is: a sample preparation device for the consolidation test of earth-rock dam materials, a floating ring type consolidation container, a floating ring is arranged inside the floating ring type consolidation container, and four hanging rings are fixedly connected to the outer circular box of the floating ring type consolidation container; after the sample is filled in the floating ring, the sample is prepared by the sample forming device, In this scheme, the sample forming device uses the reaction force static pressure mechanism to set the reaction force device; the reaction force device includes a reaction force beam, and the reaction force columns are threadedly connected at both ends of the reaction force beam; a pit is set on the ground, and a guide rail is laid on the ground above the pit, and a pulley base is slidably set on the guide rail, and a circular groove is set on the pulley base, and a floating ring type consolidation container is placed in the circular groove; The reaction column is located outside the guide rail, and the reaction column is fixedly connected to the reaction base. The reaction base is located in a pit below the ground, and a jack is placed in the pit. The jack is placed at the center position above the reaction base. A pressure plate a is movably arranged above the jack, and the floating ring consolidation container is located directly above the pressure plate a. It also includes a circular pressure plate b, a longitudinal force transmission column is placed at the center of the circular pressure plate b, and the force transmission column is located directly below the reaction beam.

[0007] The diameter of the circular pressure plate b is 2.0 mm smaller than the inner diameter of the floating ring.

[0008] The diameter of the circular groove is 2.0 mm larger than the outer diameter of the floating ring consolidation container.

[0009] The second technical solution adopted by the present invention is: a sample preparation device for the consolidation test of earth-rock dam materials, a floating ring type consolidation container, a floating ring is arranged inside the floating ring type consolidation container, and four hanging rings are fixedly connected to the upper part of the floating ring; after the sample is filled in the floating ring, the sample is prepared by the sample forming device; In this scheme, the sample forming device uses the excitation mechanism to set up a dual-machine frequency-modulated vibrator; the dual-machine frequency-modulated vibrator includes an electrically connected dual vibration motor and a frequency modulator; the dual vibration motor is fixed on a steel plate base; four steel columns are welded under the steel plate base, and a circular steel plate a is welded under the steel columns, and a stiffening triangular steel plate is also provided between the steel columns and the circular steel plate a; the two right-angled sides of the stiffening triangular steel plate are respectively welded to the steel column and the circular steel plate a.

[0010] It also includes an exciting base, which includes a steel plate b. Four groups of arc-shaped limit blocks are welded at the center of the steel plate b. The arc-shaped limit blocks are connected in sequence to form a circle with an inner diameter greater than the outer diameter of the floating ring consolidation container by 2.0 mm, which fits with the external circular box of the floating ring consolidation container.

[0011] The third technical solution adopted by the present invention is: a sample preparation method for a consolidation test of earth-rock dam materials, which specifically comprises the following steps: Step 1: Hoisting of floating ring consolidation container: Pass the two ends of the two steel cables through the four lifting rings respectively and fix them. The center positions of the two steel cables are hung on the hooks of the special equipment crane and hoisted into the circular groove of the pulley base; Step 2, sample filling: Divide the test material into equal parts and fill them into the floating ring in layers. When the static pressure of the previous layer of test material is completed, the next layer of test material is filled for static pressure. After the test material is filled and the surface is leveled, a circular pressure plate b with a diameter less than 2.0 mm from the inner diameter of the floating ring is placed above the static pressure sample. The design height of the sample is recorded as h 0 , the height of the floating ring is recorded as h 1 ,and h 0 <h 1 , the thickness of the circular pressure plate b is recorded as h 2 ; Measure the height from the upper surface of the circular pressure plate b to the top of the floating ring after each layer of test material is filled ,when When the sample needs static pressure, perform steps 3-4; in, n is the number of loading layers, the value is 1 for the first layer, 2 for the second layer, and so on; Step 3, static pressure of sample reaction force: after completing step 2, push the pulley base to move the floating ring consolidation container to the middle position of the reaction device, place a circular pressure plate b on the sample, place a force transmission column in the center of the circular pressure plate b, and make the force transmission column directly below the reaction beam. Apply pressure with a jack to lift the floating ring consolidation container and the pulley base as a whole, and the force transmission column contacts the bottom of the reaction beam to generate a reaction force; Step 4: Sample forming: Under the action of the reaction force, the sample is compressed, and the height from the upper surface of the circular pressure plate b to the top of the floating ring (2) is measured in real time using a steel ruler. , the height of the sample after static pressure is calculated h 4 ,Right now h 4 = ;when h 4 = When the static pressure is stopped, n is the number of loading layers, the first layer takes the value 1, the second layer takes the value 2, and so on; the jack is used to release the pressure, so that the floating ring consolidation container and the pulley base are lowered as a whole, the pulley base falls onto the guide rail, and then it is pushed out of the reaction device to load the next layer of test materials; Step 5. Load the test materials in layers as described in step 2. After the static pressing of the previous layer of test materials is completed, load the next layer of test materials and determine whether static pressing is required according to step 2. If static pressing is required, repeat steps 3 and 4 until the sample preparation is completed.

[0012] The fourth technical solution adopted by the present invention is a sample preparation method for a consolidation test of earth-rock dam materials, which specifically comprises the following steps: Step 1, hoisting of the floating ring consolidation container: pass the two ends of the two steel cables through the four hoisting rings respectively and fix them, hang the center positions of the two steel cables on the hooks of the special equipment crane respectively, and hoist them to the inner side of the arc limit block; Step 2: Sample filling: Divide the test material into equal parts and fill them into the floating ring in layers. When the vibration of the previous layer of test material is completed, the next layer of test material is filled and vibrated. The design height of the sample is recorded as h 0 , the height of the floating ring is recorded as h 1 , h 0 <h 1； After each layer of test material is filled, the surface is leveled and the height from the surface above the sample to the top of the floating ring is measured. h 2 ,when When the sample needs to be excited, execute steps 3-5; n is the number of loading layers, the value is 1 for the first layer, 2 for the second layer, and so on; Step 3: Calculate the excitation time: According to the formula F=mrw 2 and w= 2 πf Calculate the exciting force, where F For the exciting force, m is the mass of the vibrator eccentric block, r is the distance between the center of mass of the eccentric block and the center of rotation axis, w is the motor rotation angular frequency, f is the operating frequency of the vibration motor; in the relative density test of coarse-grained soil in the Geotechnical Test Method Standard GB / T 50123-2019, when the vibrator excitation force is 4.20 kN, the vibration contact area of ​​the sample is 706.85 cm 2 When the vibration time is 8.00min, the sample reaches the maximum dry density. The reference standard is used. After the exciting force acting on the sample surface is normalized to the load, the impulse theorem is used to calculate the excitation time of the sample in the consolidation test to be excited layer. Step 4: Sample excitation: hoist the dual-machine frequency-modulated vibrator into the floating ring, make the circular steel plate a fully contact with the sample surface, and adjust the frequency through the frequency modulator f To the set value, start the dual frequency modulated vibrator, and vibrate in two equal periods according to the time calculated in step 3; Step 5: Sample forming: After two periods of vibration, measure the height from the upper surface of the circular steel plate a to the top of the floating ring. h 3, the thickness of the circular steel plate a is recorded as h 4 , calculate the sample height after the excitation is completed h 5 , h 5 = h 1 - h 3 -h 4 ,when h 5 = When the excitation stops, n is the number of filling layers, the first layer takes the value 1, the second layer takes the value 2, and so on; lift the dual-machine frequency modulation vibrator out of the floating ring and fill the next layer of test materials; Step 6. Load the test materials in layers as described in step 2. After the vibration of the previous layer of test materials is completed, load the next layer of test materials and determine whether vibration is required according to step 2. If vibration is required, repeat steps 3, 4 and 5 until the sample preparation is completed.

[0013] Compared with the prior art, the present invention has the following beneficial effects: (1) For dam-building materials that have low sample density requirements and are easy to sample in indoor consolidation tests, the reaction static pressure sampling method is used for sampling. There is no dust during the sampling process and particle crushing is avoided to a greater extent. Compared with the traditional vibrator method, it has the advantages of environmental protection and protection of sample gradation.

[0014] (2) For dam-building materials that have high sample density requirements and are difficult to sample in indoor consolidation tests, a dual-machine frequency-modulated vibrator excitation sampling method is used. During the sample preparation process, the dual-machine frequency-modulated vibrator adjusts the excitation frequency through the frequency modulator and divides the excitation into two equal periods to avoid over-vibration or under-vibration of the sample. At the same time, the floating ring consolidation container is limited and fixed by the excitation base. During the excitation, the floating ring consolidation container is not easy to deviate, ensuring the safety of the test personnel during the sample preparation process.

[0015] The two sample preparation methods provided by the present invention meet different sample preparation requirements, have simple structures, and are easy to assemble; they are very suitable for consolidation test sample preparation requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0017] Figure 1 It is a schematic diagram of the appearance of the floating ring consolidation container and the reaction force device in the present invention.

[0018] Figure 2 It is a cross-sectional view of the floating ring consolidation container and the reaction force device in the present invention.

[0019] Figure 3 It is a schematic diagram of the dual-machine frequency modulation vibrator in the present invention.

[0020] Figure 4 It is a schematic diagram of the excitation base in the present invention.

[0021] In the figure: 1. Floating ring consolidation container; 2. Floating ring; 3. Lifting ring; 4. Reaction device; 5. Reaction beam; 6. Reaction column; 7. Ground; 8. Guide rail; 9. Pulley base; 10. Jack; 11. Reaction base; 12. Pressure plate a; 13. Circular pressure plate b; 14. Force transmission column; 15. Dual-machine frequency-modulated vibrator; 16. Stiffened triangular steel plate; 17. Frequency modulator; 18. Dual vibration motors; 19. Steel plate base; 20. Steel column; 21. Circular steel plate a; 22. Arc-shaped limit block; 23. Excitation base; 24. Steel plate b. DETAILED DESCRIPTION

[0022] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] Example 1 The present invention comprises a floating ring type consolidation container 1, wherein a floating ring 2 is provided inside the floating ring type consolidation container 1, and four hanging rings 3 are fixedly connected to the outer circular box of the floating ring type consolidation container 1; after the sample is filled in the floating ring 2, the sample is statically pressed by the reaction force device 4; according to Figure 1 and Figure 2 As shown, the reaction device 4 includes a reaction beam 5, and reaction columns 6 are threadedly connected at both ends of the reaction beam 5; a pit is set on the ground 7, and a guide rail 8 is laid on the ground 7 above the pit, and the reaction column 6 is located on the outside of the guide rail 8; a pulley base 9 is slidably connected to the guide rail 8, and a circular groove is provided on the pulley base 9, the floating ring type consolidation container 1 is placed in the circular groove, a jack 10 is placed in the pit, and a pressure plate a12 is movably provided above the jack 10, and the floating ring type consolidation container 1 is located directly above the pressure plate a12; the reaction column 6 is fixedly connected to the reaction base 11, the reaction base 11 is located in a pit below the ground 7, and the jack 10 is placed at the center position above the reaction base 11.

[0024] The outer diameter of the floating ring consolidation container is 69.5 cm, the inner diameter of the floating ring is 50.5 cm, and the height of the floating ring is 30.0 cm.

[0025] Example 2 In actual use, first level and tamp the ground, and dig a 1.0m×1.0m×0.8m pit on the leveled ground for hardening. Set a reaction base in the pit and fix it on the hardened pit ground. Fix the reaction column on the reaction base. The inner spacing between the two reaction columns is 72.0cm. After the reaction column is installed, the reaction beam is fixed on the top of the reaction column. The height of the reaction beam to the ground can be adjusted through the thread. Install the guide rail parallel to the ground inside the reaction column. The guide rail is 5.0cm wide and the inner spacing between the two guide rails is 58.0cm. Place a pulley base above the guide rail. Four pulleys are installed on the bottom of the base. It can roll forward or backward on the guide rail. The top surface of the pulley base is a square with a side length of 70.0cm, and there is a circular limit groove on the top surface with a diameter of 69.7cm. A jack with a specification of 100t is placed in the middle of the reaction base, and a rigid pressure plate a is placed above the jack. After the top surface of the pressure plate a is subjected to force, it contacts the bottom surface of the pulley base, so that the pulley base and the floating ring consolidation container above it are lifted.

[0026] Example 3 Assume that the dry density of the consolidation test specimen is 2.00 g / cm 3 , and less than the maximum dry density of the sample; according to the size of the floating ring, the sample diameter is determined to be 50.5cm, and the sample design height is 28.0cm. The sample material quantity is calculated to be 112.17kg. The test material is divided into 4 equal parts and loaded in layers. When the sample preparation of the previous layer of test material is completed, the next layer of test material is loaded, and the layer design height is 7.0cm. The sample preparation using the reaction static pressure method includes the following steps: Step 1. Hoisting of the floating ring consolidation container: Pass the two ends of the two steel cables through the four lifting rings of the floating ring consolidation container and fix them. Hang the center positions of the two steel cables on the hooks of the special equipment crane. Start the crane to hoist it to the pulley base. During the hoisting process, adjust the position of the floating ring consolidation container in real time so that it falls into the circular groove on the top surface of the pulley base.

[0027] Step 2, sample filling: The design height of the sample is 28.0cm, the height of the floating ring is 30.0cm, and 28.0cm<30.0cm is established. Divide the test materials into 4 equal parts and fill them in layers. After the static pressure of the previous layer of test materials is completed, fill the next layer of test materials. First, fill the first layer of test materials into the floating ring and level the surface, and place a circular pressure plate b13 above the sample. It is measured that the height from the upper surface of the circular pressure plate b13 to the top of the floating ring is 20.0cm. According to the formula, the sample height is 8.0cm at this time, which is greater than the layered design height of 7.0cm, so the sample needs static pressure.

[0028] Step 3, static pressure of the sample: After completing step 2, push the pulley base to move the floating ring consolidation container to the middle position of the reaction device, place the force transfer column 14 at the center of the circular pressure plate b13, make the force transfer column 14 slightly lower than the bottom of the reaction beam, and apply pressure with the jack to lift the floating ring consolidation container and the pulley base as a whole, so that the force transfer column 14 contacts the bottom of the reaction beam to generate a reaction force.

[0029] Step 4, sample forming: Under the action of the reaction force, the sample is compressed, and a steel ruler is used to measure the height from the upper surface of the circular pressure plate b13 to the top of the floating ring at 4 positions at equal intervals along the inner wall of the floating ring, and the average value is calculated. During the static pressure process, if it is calculated that the height of the layered sample after static pressure is still greater than 7.0cm, it is necessary to extend the static pressure time or increase the static pressure reaction force; when it is calculated that the height of the layered sample after static pressure is equal to 7.0cm, which meets the sample layer height, the static pressure is stopped.

[0030] After the static pressure stops, the jack releases the pressure, causing the floating ring consolidation container and the pulley base to drop as a whole. The base pulley falls onto the guide rail and is then pushed out of the reaction device to load the next layer of test materials.

[0031] Step 5. As described in step 2, the test materials are loaded in four layers. After the static pressing of the previous layer of test materials is completed, the next layer of test materials is loaded, and it is determined whether static pressing is required according to step 2. If static pressing is required, repeat steps 3 and 4 until the sample preparation is completed.

[0032] Example 4 The sample preparation device for the consolidation test of earth-rock dam materials of the present invention comprises a floating ring consolidation container 1, wherein a floating ring 2 is arranged inside the floating ring consolidation container 1, and after the sample is filled in the floating ring 2, the sample is prepared by vibration using the excitation mechanism; four hanging rings 3 are fixedly connected to the outer circular box of the floating ring consolidation container 1; Figure 3 As shown, in this scheme, a dual-machine frequency-modulated vibrator 15 is used for excitation sample preparation. The dual-machine frequency-modulated vibrator 15 includes an electrically connected dual vibration motor 18 and a frequency modulator 17; the dual vibration motor 18 is fixed on a steel plate base 19; four steel columns 20 are welded below the steel plate base 19, and a circular steel plate a21 is welded below the steel column 20. A stiffening triangular steel plate 16 is also provided between the steel column 20 and the circular steel plate a21; the two right-angled sides of the stiffening triangular steel plate 16 are welded to the steel column 20 and the circular steel plate a21 respectively. The stiffening triangular steel plate 16 plays a stabilizing role to prevent the four steel columns from bending and deforming during excitation. A frequency modulator 17 is installed on the power line of the dual vibration motor 18 to adjust the excitation frequency of the dual-machine frequency-modulated vibrator, and the adjustment range frequency is 0~30Hz.

[0033] Example 5 Based on Example 4, The sample preparation device for the consolidation test of earth-rock dam building materials of the present invention is as follows: Figure 4 As shown, it also includes an excitation base 23, which includes a steel plate b24 with a thickness of 3.0 cm and a diameter of 1.5 m. Four sets of arc-shaped limit blocks 22 are welded at the center of the steel plate b24, which are connected in sequence to form a circle with an inner diameter of 69.7 cm, which fits the outer circular box of the floating ring consolidation container.

[0034] Example 6 Assuming the test dry density is 2.20g / cm 3 , and is equal to the maximum dry density. According to the size of the floating ring, the sample diameter is determined to be 50.5 cm, and the sample design height is 28.0 cm. The sample material amount is calculated to be 123.38 kg. The test material is divided into 4 equal parts and loaded in layers. When the sample preparation of the upper layer of test material is completed, the next layer of test material is loaded, and the layer design height is 7.0 cm. Using the device of Example 5, the double-machine frequency modulation excitation sample preparation method includes the following steps: Step 1. Hoisting of the floating ring consolidation container: Pass the two ends of the two steel cables through the four lifting rings of the floating ring consolidation container and fix them. Hang the center positions of the two steel cables on the hooks of the special equipment crane, start the crane for hoisting, and adjust the position of the floating ring consolidation container in real time during the hoisting process so that it falls within the limit block of the exciting base.

[0035] Step 2, sample filling: The design height of the sample is 28.0cm, the height of the floating ring is 30.0cm, and 28.0cm<30.0cm is established. Divide the test material into 4 equal parts and fill them in layers. After the vibration of the previous layer of test material is completed, fill the next layer of test material. Fill the first layer of test material into the floating ring and level the surface. The height from the top of the sample to the top of the floating ring is measured to be 19.0cm. The calculated sample height is 9.0cm, which is greater than the layered design height of 7.0cm. The required compression of the sample is 2.0cm, and the sample needs to be vibrated.

[0036] Step 3: Calculate the excitation time: According to the formula F=mrw 2 and w= 2 πf Calculate the exciting force, where F is the exciting force (N), m is the mass of the vibrator eccentric block (kg), r is the distance between the center of mass of the eccentric block and the center of rotation axis (m), w is the motor rotation angular frequency, f is the operating frequency of the vibration motor. In the coarse-grained soil relative density test, the vibrator excitation force is 4.20 kN and the sample vibration contact area is 706.85 cm 2, the vibration time of 8.00min can reach the maximum dry density requirement of the sample; Taking this as a reference standard, the excitation force acting on the sample surface is normalized to load, and the impulse theorem is used to calculate the vibration time of the consolidation test layered sample. According to the above requirements, the time corresponding to different excitation frequencies is calculated and shown in Table 1 below: Table 1. Excitation frequency ~ time correspondence table

[0037] Step 4: Sample excitation: After completing step 2, hoist the dual-machine frequency-modulated vibrator into the floating ring so that the circular steel plate a21 is in full contact with the sample surface. Adjust the excitation frequency through the frequency modulator. f Set the value, start the vibrator, and vibrate in two equal periods according to the time calculated in step 3.

[0038] After the first layer of samples is excited for a period of time, if the compression of the sample is greater than 1.0cm, the excitation frequency needs to be reduced in the next period; if it is less than 1.0cm, the excitation frequency needs to be increased in the next period. When it is equal to 1.0cm, the excitation frequency can be maintained and the next period of excitation can be directly carried out. The excitation frequency of the subsequent layered samples is also adjusted according to the relationship between the actual compression amount of each period and the required compression amount of each period.

[0039] Step 5, sample forming: After the two-period vibration is completed, use a steel ruler to measure the height from the upper surface of the circular steel plate a21 to the top of the floating ring at 4 positions at equal intervals along the inner wall of the floating ring. If the height of the layered sample after vibration is still greater than 7.0 cm, increase the vibration frequency according to the required recompression of the sample, and continue to vibrate in two periods with reference to the time measured in step 3; when the height of the layered sample after vibration is calculated to be 7.0 cm, which meets the design height of the sample layer, stop the vibration. Lift the dual-machine frequency modulation vibrator out of the floating ring and load the next layer of test materials.

[0040] Step 6. As described in step 2, the test materials are loaded in four layers. After the vibration of the previous layer is completed, load the next layer of test materials. Determine the required compression amount of this layer of test materials according to step 2 and determine whether vibration is required. If vibration is required, refer to the vibration frequency-time correspondence table in step 3 and repeat steps 4 and 5 until the sample preparation is completed.

[0041] The above are only preferred embodiments of the present invention. The present invention will not be limited to the embodiments shown herein, but should conform to the widest scope consistent with the principles and novel features disclosed herein. Any simple modification, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. Sample preparation device for consolidation test of earth-rock dam materials, characterized by: The invention comprises a floating ring type consolidation container (1), wherein a floating ring (2) is provided inside the floating ring type consolidation container (1), and after a sample is filled in the floating ring (2), a sample is prepared by a sample forming device.

2. The sample preparation device for the consolidation test of earth-rock dam materials according to claim 1 is characterized in that: Four lifting rings (3) are fixedly connected to the outer circular box body of the floating ring type consolidation container (1).

3. The sample preparation device for consolidation test of earth-rock dam materials according to claim 2, characterized in that: The sample forming device uses a reaction force static pressure mechanism to set a reaction force device (4), wherein the reaction force device (4) comprises a reaction force beam (5), and both ends of the reaction force beam (5) are threadedly connected to reaction force columns (6); A pit is provided on the ground (7), a guide rail (8) is laid on the ground (7) above the pit, a pulley base (9) is slidably provided on the guide rail (8), a circular groove is provided on the pulley base (9), and the floating ring type consolidation container (1) is placed in the circular groove; The reaction column (6) is located outside the guide rail (8); the reaction column (6) is fixedly connected to the reaction base (11); the reaction base (11) is located in a pit below the ground (7); a jack (10) is placed in the pit; the jack (10) is placed at a central position above the reaction base (11); A pressure plate a (12) is movably arranged above the jack (10), and the floating ring consolidation container (1) is located directly above the pressure plate a (12); It also includes a circular pressure-bearing plate b (13), a force-transmitting column (14) is placed at the center of the circular pressure-bearing plate b (13), and the force-transmitting column (14) is located directly below the reaction beam (5).

4. The sample preparation device for consolidation test of earth-rock dam materials according to claim 3, characterized in that: The diameter of the circular pressure plate b (13) is 2.0 mm smaller than the inner diameter of the floating ring (2).

5. The sample preparation device for consolidation test of earth-rock dam materials according to claim 3, characterized in that: The diameter of the circular groove is 2.0 mm larger than the outer diameter of the floating ring consolidation container (1).

6. The sample preparation device for consolidation test of earth-rock dam materials according to claim 2, characterized in that: The sample forming device uses an excitation mechanism to set up a dual-machine frequency-modulated vibrator (15), and the dual-machine frequency-modulated vibrator (15) includes a dual vibration motor (18) and a frequency modulator (17) that are electrically connected; the dual vibration motor (18) is fixed on a steel plate base (19); four steel columns (20) are welded below the steel plate base (19), and a circular steel plate a (21) is welded below the steel columns (20); a stiffening triangular steel plate (16) is also provided between the steel columns (20) and the circular steel plate a (21); two right-angled sides of the stiffening triangular steel plate (16) are respectively welded to the steel column (20) and the circular steel plate a (21).

7. The sample preparation device for the consolidation test of earth-rock dam materials according to claim 6, characterized in that: It also includes an excitation base (23), the excitation base (23) including a steel plate b (24), four groups of arc-shaped limit blocks (22) are welded at the center of the steel plate b (24), and the arc-shaped limit blocks (22) are connected in sequence to form a circle with an inner diameter greater than the outer diameter of the floating ring consolidation container (1) by 2.0 mm, and fits with the outer circular box of the floating ring consolidation container (1).

8. Sample preparation method for consolidation test of earth-rock dam materials, characterized in that: The sample preparation device for consolidation test of earth-rock dam materials according to any one of claims 3 to 5 is used, and the specific operating steps are as follows: Step 1, hoisting of the floating ring type consolidation container: pass the two ends of the two steel cables through the four hoisting rings (3) respectively and fix them, hang the center positions of the two steel cables on the hooks of the special equipment crane respectively, and hoist them into the circular groove of the pulley base (9); Step 2, sample filling: the test material is divided into equal parts and loaded into the floating ring (2) in layers. When the static pressure of the previous layer of test material is completed, the next layer of test material is loaded for static pressure. After the test material is loaded and the surface is leveled, a circular pressure plate b (13) with a diameter smaller than the inner diameter of the floating ring (2) by 2.0 mm is placed above the sample to be statically pressurized. The design height of the sample is recorded as h 0, the height of the floating ring (2) is recorded as h 1, and h 0 <h 1. The thickness of the circular pressure plate b (13) is recorded as h 2. Measure the height from the upper surface of the circular pressure plate b (13) to the top of the floating ring (2) after each layer of test material is filled. ,when When the sample needs static pressure, perform steps 3-4; in, n is the number of loading layers, the value is 1 for the first layer, 2 for the second layer, and so on; Step 3, static pressure of sample reaction force: after completing step 2, push the pulley base (9) to move the floating ring type consolidation container (1) to the middle position of the reaction force device (4), place a circular pressure plate b (13) on the sample, place a force transmission column (14) at the center of the circular pressure plate b (13), so that the force transmission column (14) is located directly below the reaction beam (5), and the jack (10) applies pressure to lift the floating ring type consolidation container (1) and the pulley base (9) as a whole, so that the force transmission column (14) contacts the bottom of the reaction beam (5) to generate reaction force; Step 4: Sample forming: Under the action of the reaction force, the sample is compressed, and the height from the upper surface of the circular pressure plate b (13) to the top of the floating ring (2) is measured in real time using a steel ruler. , the height of the sample after static pressure is calculated h 4, namely h 4 = ;when h 4= When the static pressure stops, n is the number of loading layers, which is 1 for the first layer, 2 for the second layer, and so on; the jack is used to release pressure, so that the floating ring consolidation container (1) and the pulley base (9) are lowered as a whole, and the pulley base (9) falls onto the guide rail (8), and then is pushed out of the reaction device to load the next layer of test materials; Step 5. Load the test materials in layers as described in step 2. After the static pressing of the previous layer of test materials is completed, load the next layer of test materials and determine whether static pressing is required according to step 2. If static pressing is required, repeat steps 3 and 4 until the sample preparation is completed.

9. Sample preparation method for consolidation test of earth-rock dam materials, characterized by: The sample preparation device for the consolidation test of earth-rock dam materials according to claim 7 is used, and the specific operating steps are as follows: Step 1, hoisting of the floating ring type consolidation container: pass the two ends of the two steel cables through the four hoisting rings (3) respectively and fix them, hang the center positions of the two steel cables on the hooks of the special equipment crane respectively, and hoist them to the inner side of the arc-shaped limit block (22); Step 2, sample filling: Divide the test material into equal parts and fill them into the floating ring (2) in layers. After the vibration of the previous layer of test material is completed, the next layer of test material is filled and vibrated. The design height of the sample is recorded as h 0, the height of the floating ring is recorded as h 1, h 0 <h 1. After each layer of test material is filled, level the surface and measure the height from the surface above the sample to the top of the floating ring (2). h 2. When When the sample needs to be excited, execute steps 3-5; n is the number of loading layers, the value is 1 for the first layer, 2 for the second layer, and so on; Step 3: Calculate the excitation time: According to the formula F=mrw 2 and w= 2 πf Calculate the exciting force, where F For the exciting force, m is the mass of the vibrator eccentric block, r is the distance between the center of mass of the eccentric block and the center of rotation axis, w is the motor rotation angular frequency, f is the operating frequency of the vibration motor; Step 4: Sample excitation: hoist the dual frequency modulated vibrator (15) into the floating ring (2), so that the circular steel plate a (21) is in full contact with the sample surface, and adjust the frequency through the frequency modulator (17). f To the set value, start the dual frequency modulated vibrator, and vibrate in two equal periods according to the time calculated in step 3; Step 5: Sample forming: After two periods of vibration, measure the height from the upper surface of the circular steel plate a (21) to the top of the floating ring. h 3. The thickness of the circular steel plate a (21) is recorded as h 4. Calculate the sample height after vibration is completed h 5. h 5 = h 1 - h 3 -h 4. When h 5= When the excitation stops, n is the number of loading layers, the first layer is 1, the second layer is 2, and so on; the dual-machine frequency modulation vibrator (15) is hoisted out from the floating ring, and the next layer of test materials is loaded; Step 6. Load the test materials in layers as described in step 2. After the vibration of the previous layer of test materials is completed, load the next layer of test materials and determine whether vibration is required according to step 2. If vibration is required, repeat steps 3, 4 and 5 until the sample preparation is completed.

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