Device and method for testing dry density of on-site originally-graded filling material

Abstract

The invention relates to the technical field of earth and rockfill dam damming filler dry density testing, in particular to a device and a method for testing the dry density of an on-site original grading filling material. The test device comprises an air generator, and the air generator is provided with an air storage tank. A digital display type pressure gauge is arranged on the gas storage tank and is used for detecting the gas pressure in the gas storage tank; the device further comprises a cover body and an inflatable bag. The cover body is provided with a cavity with an open lower end; the cover body comprises a positioning ring and a cover plate arranged at the top of the positioning ring; the cover plate is detachably connected with the positioning ring; an adapter tube is inserted into a central through hole of the cover plate; a bag catheter is arranged on an air inlet of the inflatable bag; the bag guide pipe is connected with the air outlet end of an adapter pipe, and the air inlet end of the adapter pipe is connected with the air storage tank through an air conveying pipeline. Compared with an irrigation method, the test method provided by the invention has the advantages that the precision and accuracy of test pit volume measurement can be improved; compared with a sand filling method, the material cost can be reduced.

Description

Technical Field

[0001] The invention relates to the technical field of testing dry density of filling materials for earth-rock dam construction, and in particular to a testing device and method for dry density of on-site original graded filling materials. Background Art

[0002] At present, there are two methods for testing the filling quality of filling materials, namely, digging a pit and filling it with sand and digging a pit and filling it with water. The digging a pit and filling it with water is commonly used. The basic principle of the above two methods is to replace the volume of the test pit based on the volume of standard sand (or water).

[0003] The pit digging and sand filling method has the following disadvantages: the test pit is usually large in size, requiring a large amount of standard sand, and the density of the standard sand needs to be calibrated regularly, resulting in high testing costs; in order to save costs, if the contaminated standard sand is recovered after the test, it will take a lot of time.

[0004] The pit digging and watering method has the following disadvantages: before watering, a plastic film needs to be laid in the test pit, and the film needs to be spread to make it close to the surface of the test pit during watering; during the watering process, the film is easily piled up under the pressure of water, causing volume measurement errors; due to the thin thickness of the film, the speed and flow of water injection need to be controlled during the watering process to avoid damage to the film caused by water injection or overflow of water from the test pit, causing volume measurement errors; on the other hand, the film is prone to damage during use and needs to be replaced at any time, increasing the test cost.

[0005] In addition, when using the water filling method, due to limited conditions, the water used is usually turbid, and the tester tends to ignore the effect of water temperature on density. When calculating the volume of the test pit, the density is still 1.00g / cm 3 Calculation results in deviation in the test pit volume. Summary of the invention

[0006] The main purpose of the present invention is to provide a test device and method for the dry density of original graded filling materials on site, aiming to solve the above technical problems.

[0007] To achieve the above-mentioned purpose, on the one hand, the present invention proposes a test device for the dry density of on-site original graded filling materials, comprising an air generator, the air generator is equipped with an air tank; the air tank is provided with a digital pressure gauge for detecting the gas pressure in the air tank; it also includes a cover body and an inflatable bag; the cover body has a cavity with an open lower end; the cover body includes a positioning ring and a cover plate arranged on the top of the positioning ring; the cover plate and the positioning ring are detachably connected; a transfer tube is inserted in the central through hole of the cover plate; a bag duct is provided on the air inlet of the inflatable bag; the bag duct is connected to the air outlet end of the transfer tube, and the air inlet end of the transfer tube is connected to the air tank through a gas pipeline.

[0008] Preferably, a latch hole is provided on the top surface of the positioning ring, and a latch is provided on the bottom surface of the cover plate near the edge, and the latch is inserted into the latch hole.

[0009] Preferably, the cover plate is made of transparent material.

[0010] Preferably, the positioning ring is a rectangular frame formed by splicing four strip plates, and two adjacent strip plates are connected by a magnetic block.

[0011] Preferably, nails are provided on the bottom surface of the positioning ring.

[0012] Preferably, the inflatable bag is made of polyurethane rubber and is in the shape of a spherical bag. The inflatable bag has specifications of different radius sizes, including 40cm, 44cm, 46cm, 48cm, 50cm, 52cm and 55cm.

[0013] Preferably, a rubber sealing layer is bonded to the inner wall of the transfer tube; the upper end of the balloon catheter is inserted into the transfer tube and sealed by the rubber sealing layer; the outer peripheral surface of the upper half of the transfer tube is provided with an external thread for threaded connection with the gas pipeline.

[0014] On the other hand, the present invention also provides a test method for the dry density of the original graded filling material on site, using the above test device, comprising the following steps:

[0015] S1. Select the test site on the filling material, buckle the positioning ring on the test site, and ensure that the bottom surface of the positioning ring is in close contact with the surface of the filling material;

[0016] S2. Connect the bag conduit on the inflatable bag to the transfer tube on the cover plate. Connect the air inlet end of the transfer tube to the gas tank through the gas pipeline. Install the cover plate on the positioning ring to form a complete cover plate, and make the inflatable bag located in the inner cavity of the cover body. Record the initial pressure P of the gas tank. 0 ;

[0017] S3. Use the gas tank to inject air into the inflatable bag. When the inflatable bag fills the internal space of the cover, stop injecting gas and record the pressure p of the gas tank at this time. 1 , calculate the volume V of the filling material surface and the internal space of the cover at the test site 1 ;

[0018] S4. Remove the cover plate, release the air in the inflatable bag, and take out the inflatable bag; dig samples of the filling material at the area inside the positioning ring to obtain a test pit; and weigh the mass of all the samples dug out m 1 ;

[0019] S5. After placing the inflatable bag into the test pit, connect the bag conduit on the inflatable bag to the transfer tube on the cover plate, connect the air inlet end of the transfer tube to the gas tank through the gas pipeline, and install the cover plate on the positioning ring to form a complete cover plate; record the pressure p′ of the gas tank at this time 0 ;

[0020] S6. Use the gas tank to inject air into the inflatable bag. When the inflatable bag fills the inner space of the cover body and the test pit, stop injecting gas and record the pressure p of the gas tank at this time. 2 , calculate the cavity volume V formed by the cover and the test pit 2 ; Then calculate the volume V of the test pit 3 ;

[0021] S7, measuring the moisture content of fillers in different particle size groups by graded measurement, and taking the weighted calculation result of the moisture content of particles in each particle size group as the final moisture content ω of the filling material;

[0022] S8. Calculate the density ρ of the sample in the test pit and the dry density ρ of the sample in the test pit d .

[0023] Preferably, in step S3, the volume V of the filling material surface and the internal space of the cover body at the test site is calculated using the following formula: 1 :

[0024] p 0 V 0 =p 1 (V 1 +V 0 )

[0025]

[0026] Among them, V 0 is the volume of the gas tank;

[0027] In step S6, the volume V of the test pit is calculated using the following formula: 3 :

[0028]

[0029] V 3 =V 2 -V 1 ;

[0030] Where: V 2 It is the cavity volume formed by the cover body and the test pit.

[0031] Preferably, when calculating the density ρ of the sample in the test pit and the dry density ρ of the sample in the test pit d When the volume V of the test pit is measured, it is necessary to repeat steps S5 and S6 for multiple times.3 , and take the average of multiple measurements As the final volume of the test pit; calculate the density ρ and dry density ρ of the sample in the test pit according to the following formula d :

[0032]

[0033]

[0034] Due to the adoption of the above technical solution, the beneficial effects of the present invention are as follows:

[0035] By using the test device and method provided by the present invention, the volume of the test pit is calculated using the principle of Boyle's law, which can improve the precision and accuracy of the test pit volume measurement compared with the water filling method; and can reduce the material cost compared with the sand filling method. In addition, by using the test device and method provided by the present invention, the test time can be saved and the work efficiency can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0037] Figure 1 A schematic diagram of the test device provided by the present invention;

[0038] Figure 2 It is a structural schematic diagram of the cover plate in the present invention;

[0039] Figure 3 It is a structural schematic diagram of the positioning ring in the present invention;

[0040] Figure 4 It is a schematic diagram of the connection structure between the balloon catheter and the transfer tube in the present invention;

[0041] Figure 5 It is a schematic diagram of the structure of the inflatable balloon and balloon catheter in the present invention;

[0042] Figure 6 Schematic diagram of the test device provided by the present invention when conducting the test Figure 1 ;

[0043] Figure 7 Schematic diagram of the test device provided by the present invention when conducting the test Figure 2 .

[0044] Explanation of the accompanying drawings: 1. Air generator; 1a. Air storage tank; 2. Cover body; 3. Positioning ring; 3a. Pin hole; 3b. Strip plate; 3c. Magnetic block; 4. Cover plate; 4a. Pin; 5. Inflatable bag; 5a. Bag catheter; 6. Adapter tube; 6a. Rubber sealing layer; 6b. External thread; 7. Gas transmission pipeline; 8. Filling material; 8a. Test pit. DETAILED DESCRIPTION

[0045] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0047] Combination Figures 1 to 5 As shown, on the one hand, this embodiment provides a test device for the dry density of the original graded filling material on site, including an air generator 1, and the air generator 1 is equipped with a gas storage tank 1a; a digital pressure gauge is provided on the gas storage tank 1a, which is used to detect the gas pressure in the gas storage tank 1a; in this embodiment, the air generator 1 uses a screw air generator, and the air generator is a device that compresses air through a compressor and stores it in the gas storage tank 1a, which mainly consists of a compressor, a gas storage tank 1a, a filter, a drying chamber and other main parts. The air generator 1 is a conventional existing equipment and will not be described here. The capacity of the gas storage tank 1a of the selected air generator 1 is 650L, and the gas outlet of the gas storage tank 1a controls the speed of gas output through a flow meter.

[0048] The test device also includes a cover 2 and an inflatable bag 5; the inflatable bag 5 is made of polyurethane rubber, is in the shape of a spherical bag, and has specifications of different radius sizes, including 40cm, 44cm, 46cm, 48cm, 50cm, 52cm and 55cm. The cover 2 has a cavity with an open lower end; the cover 2 includes a positioning ring 3 and a cover plate 4 arranged on the top of the positioning ring 3; the cover plate 4 is detachably connected to the positioning ring 3; a transfer tube 6 is inserted into the central through hole of the cover plate 4; a bag conduit 5a is arranged on the air inlet of the inflatable bag 5; the bag conduit 5a is connected to the air outlet end of the transfer tube 6, and the air inlet end of the transfer tube 6 is connected to the gas storage tank 1a through a gas pipeline 7.

[0049] Combination Figure 2 and Figure 3 As shown, the connection method between the cover plate 4 and the positioning ring 3 is a latch connection. Specifically, a latch hole 3a is provided on the top surface of the positioning ring 3, and a latch 4a is provided on the bottom surface of the cover plate 4 near the edge, and the latch 4a is inserted into the latch hole 3a.

[0050] In order to facilitate observation of the inflation of the inflatable bag 5 inside the cover body 2 during the test, the cover plate 4 is made of a transparent material. According to the inflation of the inflatable bag 5, it is determined when to close the gas tank 1a to stop the gas supply.

[0051] Combination Figure 3 As shown, the positioning ring 3 is a rectangular frame formed by splicing four strip plates 3b, and two adjacent strip plates 3b are connected by magnetic blocks 3c. The magnetic blocks 3c are used to connect the four strip plates 3b, so that the positioning ring 3 can be quickly spliced ​​together. In this embodiment, the positioning rings 3 of different specifications can be spliced ​​together by using strip plates 3b of different lengths. The length × width × height dimensions of the spliced ​​positioning ring 3 include three specifications: 1.0m × 1.0m × 0.01m, 1.5m × 1.5m × 0.01m, and 2.0m × 2.0m × 0.01m.

[0052] Furthermore, in order to prevent the positioning ring 3 from sliding when it is buckled on the filling material 8 , a nail 3 d is provided on the bottom surface of the positioning ring 3 , and the nail 3 a is inserted into the filling material 8 .

[0053] Combination Figure 4 As shown, a rubber sealing layer 6a is bonded to the inner wall of the transfer tube 6; the upper end of the bag catheter 5a is inserted into the transfer tube 6 and sealed by the rubber sealing layer 6a; the outer peripheral surface of the upper half of the transfer tube 6 is provided with an external thread 6b for threaded connection with the gas pipeline 7.

[0054] Combination Figure 6 and Figure 7 As shown, this embodiment also provides a test method for the dry density of the original graded filling material on site, using the above test device, including the following steps:

[0055] S1. Select a test site on the filling material 8, buckle the positioning ring 3 on the test site, and ensure that the bottom surface of the positioning ring 3 is in close contact with the surface of the filling material 8; when the positioning ring 3 is buckled on the filling material 8, use the nails 3a on the positioning ring 3 to insert into the filling material 8 to avoid sliding, and ensure that the positioning ring 3 is in close contact with the surface of the filling material 8. If the gap between the positioning ring 3 and the filling material 8 is large due to the unevenness of the test site, it can be filled with filling material.

[0056] S2, connect the bag conduit 5a on the inflatable bag 5 with the transfer tube 6 on the cover plate 4, connect the air inlet end of the transfer tube 6 with the gas storage tank 1a through the gas pipeline 7, install the cover plate 4 on the positioning ring 3 to form a complete cover plate 2, and make the inflatable bag 5 located in the inner cavity of the cover body 2, as shown in detail. Figure 6 As shown. And record the initial pressure P of the gas tank 1a 0 .

[0057] S3. Use the gas storage tank 1a to inject air into the inflatable bag 5. When the inflatable bag 5 fills the internal space of the cover body 2, stop injecting gas and record the pressure p of the gas storage tank 1a at this time. 1 , calculate the volume V of the filling material surface and the internal space of the cover 2 at the test site 1 ; The specific calculation is based on the following formula:

[0058]

[0059] Among them, V 0 is the volume of the gas tank 1a, in cm 3 .

[0060] S4, remove the cover plate 4, release the air in the inflatable bag 5, and take out the inflatable bag 5; dig a sample of the filling material 8 at the area inside the positioning ring 3 to obtain a test pit 8a; and weigh the mass m of all the samples dug out. 1 The ratio of the depth to the diameter of the test pit 8a is 1:2 to 1:4, and the diameter of the test pit 8a is not less than 20cm. When digging the sample, first dig vertically to the depth and then expand to the specified diameter. The bottom of the test pit 8a should be flat and free of loose materials. When excavating, avoid disturbing the pit wall; when there is a deep depression on the pit wall, fill it with filling materials. There should be no large protrusions and sharp edges on the pit wall.

[0061] S5. According to the diameter of the test pit 8a, select an inflatable bag 5 of a suitable size, and after placing the inflatable bag 5 into the test pit 8a, connect the bag conduit 5a on the inflatable bag 5 with the transfer tube 6 on the cover plate 4, and connect the air inlet end of the transfer tube 6 with the gas storage tank 1a through the gas pipeline 7, and install the cover plate 4 on the positioning ring 3 to form a complete cover plate 2; record the pressure p′ of the gas storage tank 1a at this time 0 .

[0062] S6. Use the gas storage tank 1a to inject air into the inflatable bag 5. When the inflatable bag 5 fills the internal space of the cover body 2 and the test pit 8a, stop injecting gas and record the pressure p of the gas storage tank 1a at this time. 2 , calculate the cavity volume V formed by the cover 2 and the test pit 8a 2 ; Then calculate the volume V of the test pit 8a 3 ; The specific calculation is based on the following formula:

[0063]

[0064] V 3 =V 2 -V 1 ;

[0065] Where: V 2 It is the cavity volume formed by the cover body 2 and the test pit 8a.

[0066] S7. Determine the moisture content of fillers in different particle size groups by graded measurement, and take the weighted calculation result of the moisture content of particles in each particle size group as the final moisture content ω of the filling material.

[0067] S8. Calculate the density ρ of the sample in the test pit and the dry density ρ of the sample in the test pit d Specifically, when calculating the density ρ of the sample in the test pit and the dry density ρ of the sample in the test pit, d When the volume V of the test pit 8a is measured multiple times, it is necessary to repeat steps S5 and S6. 3 , and take the average of multiple measurements As the final volume of the test pit 8a; the density ρ and dry density ρ of the sample in the test pit are calculated according to the following formula d :

[0068]

[0069]

[0070] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A test device for the dry density of original graded filling materials on site, comprising an air generator (1), wherein the air generator (1) is provided with a gas storage tank (1a); a digital pressure gauge is arranged on the gas storage tank (1a) for detecting the gas pressure in the gas storage tank (1a); and the device is characterized in that: It also includes a cover body (2) and an inflatable bag (5); The cover body (2) has a cavity with an open lower end; the cover body (2) comprises a positioning ring (3) and a cover plate (4) arranged on the top of the positioning ring (3); the cover plate (4) and the positioning ring (3) are detachably connected; a transfer tube (6) is inserted into the central through hole of the cover plate (4); A bag catheter (5a) is provided on the air inlet of the inflatable bag (5); The bag catheter (5a) is connected to the air outlet end of the adapter tube (6), and the air inlet end of the adapter tube (6) is connected to the air storage tank (1a) via a gas transmission pipeline (7).

2. The test device according to claim 1, characterized in that A pin hole (3a) is provided on the top surface of the positioning ring (3), a pin (4a) is provided on the bottom surface of the cover plate (4) near the edge, and the pin (4a) is inserted into the pin hole (3a).

3. The test device according to claim 1, characterized in that The cover plate (4) is made of a transparent material.

4. The test device according to claim 1, characterized in that The positioning ring (3) is a rectangular frame formed by splicing four strip plates (3b), and two adjacent strip plates (3b) are connected via a magnetic attraction block (3c).

5. The test device according to claim 1, characterized in that: A nail (3d) is arranged on the bottom surface of the positioning ring (3).

6. The test device according to claim 1, characterized in that: The inflatable bag (5) is made of polyurethane rubber and is in the shape of a spherical bag. The inflatable bag (5) has specifications with different radius sizes, including 40 cm, 44 cm, 46 cm, 48 cm, 50 cm, 52 cm and 55 cm.

7. The test device according to claim 1, characterized in that A rubber sealing layer (6a) is bonded to the inner wall of the transfer tube (6); the upper end of the bag catheter (5a) is inserted into the transfer tube (6) and sealed by the rubber sealing layer (6a); and the outer peripheral surface of the upper half of the transfer tube (6) is provided with an external thread (6b) for threaded connection with the gas pipeline (7).

8. A test method for the dry density of on-site original graded filling materials, characterized in that: The test device according to any one of claims 1 to 7 comprises the following steps: S1. Select a test site on the filling material (8), buckle the positioning ring (3) on the test site, and ensure that the bottom surface of the positioning ring (3) is in close contact with the surface of the filling material (8); S2, connecting the bag conduit (5a) on the inflatable bag (5) to the transfer tube (6) on the cover plate (4), connecting the air inlet end of the transfer tube (6) to the gas storage tank (1a) via the gas transmission pipeline (7), installing the cover plate (4) on the positioning ring (3) to form a complete cover plate (2), and making the inflatable bag (5) located in the inner cavity of the cover body (2); recording the initial pressure P0 of the gas storage tank (1a); S3, using the gas storage tank (1a) to inject air into the inflatable bag (5), when the inflatable bag (5) fills the internal space of the cover body (2), stop injecting gas, record the pressure p1 of the gas storage tank (1a) at this time, and calculate the volume V1 of the filling material surface of the test part and the internal space of the cover body (2); S4, remove the cover plate (4), release the air in the inflatable bag (5), and take out the inflatable bag (5); dig a sample of the filling material (8) at the area inside the positioning ring (3) to obtain a test pit (8a); and weigh the mass m1 of all the samples dug; S5. After placing the inflatable bag (5) into the test pit (8a), connect the bag conduit (5a) on the inflatable bag (5) to the transfer tube (6) on the cover plate (4), connect the air inlet end of the transfer tube (6) to the gas storage tank (1a) via the gas pipeline (7), and install the cover plate (4) on the positioning ring (3) to form a complete cover plate (2); record the pressure p′0 of the gas storage tank (1a) at this time; S6. Use the gas storage tank (1a) to inject air into the inflatable bag (5). When the inflatable bag (5) fills the internal space of the cover body (2) and the test pit (8a), stop injecting gas, record the pressure p2 of the gas storage tank (1a) at this time, calculate the volume V2 of the cavity formed by the cover body (2) and the test pit (8a); and then calculate the volume V3 of the test pit (8a); S7, measuring the moisture content of fillers in different particle size groups by graded measurement, and taking the weighted calculation result of the moisture content of particles in each particle size group as the final moisture content ω of the filling material; S8. Calculate the density ρ of the sample in the test pit and the dry density ρ of the sample in the test pit d .

9. The test method according to claim 8, characterized in that In step S3, the volume V1 of the internal space of the cover body (2) is calculated using the following formula: p0V0=p1(V1+V0) Wherein, V0 is the volume of the gas storage tank (1a); In step S6, the volume V3 of the test pit (8a) is calculated using the following formula: p'0V0=p2(V2+V0) V3 = V2 - V1; Wherein: V2 is the volume of the cavity formed by the cover body (2) and the test pit (8a).

10. The test method according to claim 8, characterized in that In calculating the density ρ of the sample in the test pit and the dry density ρ of the sample in the test pit d When the volume V3 of the test pit (8a) is measured multiple times, it is necessary to repeat steps S5 and S6 and take the average value of the multiple measured values. As the final volume of the test pit (8a); calculate the density ρ and dry density ρ of the sample in the test pit according to the following formula d :

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