CN212083439U - Hydraulic asphalt concrete construction workability test device - Google Patents
Hydraulic asphalt concrete construction workability test device Download PDFInfo
- Publication number
- CN212083439U CN212083439U CN202021021561.7U CN202021021561U CN212083439U CN 212083439 U CN212083439 U CN 212083439U CN 202021021561 U CN202021021561 U CN 202021021561U CN 212083439 U CN212083439 U CN 212083439U
- Authority
- CN
- China
- Prior art keywords
- asphalt concrete
- platform
- workability
- connecting plate
- concrete construction
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Abstract
The utility model relates to a technical field of hydraulic engineering asphalt concrete construction workability evaluation, concretely relates to hydraulic engineering asphalt concrete construction workability test device. The device comprises a lower platform arranged on the ground and a cantilever crane arranged on one side of the lower platform. The upper platform is arranged above the lower platform through a connecting rod, and a spring is arranged between the upper platform and the lower platform. The vibrator is arranged between the upper platform and the lower platform and is fixedly installed at the lower end of the upper platform. The sample cartridge assembly is mounted on the upper platform. The two removable sample cartridges form a complete cylindrical barrel shape. The inner diameter of the sleeve is consistent with that of the cylindrical barrel, and the sleeve is connected to the upper top end of the detachable sample cylinder. A weight assembly is embedded in the top of the sample cartridge assembly. The utility model discloses a to the improvement of structure, provide a device of the preparation asphalt concrete test piece of the work progress of laminating more, structure are simpler, provide the guidance to evaluating hydraulic engineering asphalt concrete construction workability.
Description
Technical Field
The utility model relates to a technical field of hydraulic engineering asphalt concrete construction workability evaluation, concretely relates to hydraulic engineering asphalt concrete construction workability test device.
Background
The asphalt concrete material is a mixture composed of coarse and fine aggregates, asphalt and filler, and is widely used in various projects. The workability of the construction of the asphalt mixture is represented by the difficulty degree of the operability of the asphalt mixture in the processes of mixing, paving and rolling. In hydraulic engineering, the asphalt mixture should have good construction workability, and the workability in the construction stage is directly related to the mechanical property, the seepage-proofing strength and the construction quality of a dam body. The better the workability of the asphalt mixture, the easier it is to mix, spread and compact, and the easier it is to plastically form into a qualified dam structure.
At present, before the asphalt concrete is applied to engineering construction, a sample block of the asphalt concrete needs to be tested. The traditional test adopts a Marshall compaction method, and achieves the purpose of mixture forming by compacting the mixture through a heavy hammer. The method is greatly different from a method for vibrating and rolling asphalt concrete by a road roller in the actual construction process, and the guide effect of the test result on the site construction is limited.
Chinese patent document CN100427917C discloses an indoor asphalt mixture rotary vibration compactor. The device is provided with guide rods or slide rails on the left side and the right side of a frame, and a vibration system is arranged on the guide rods. The vibration system comprises an upper vehicle mechanism and a lower vehicle mechanism connected with the upper vehicle mechanism. The upper end of the frame is provided with a hand wheel shaft, the upper end of which is connected with the hand wheel and the lower end of which is connected with the hook. Two ends of the steel wire rope are fixedly connected to the upper part of the upper vehicle mechanism, and the middle part of the steel wire rope is hung on the hook. The bottom of the frame is provided with a motor frame and a support column connected with the rotary chassis. The motor is arranged on the motor frame and is connected with the rotating chassis through a transmission mechanism. And a test piece mold base provided with a test piece mold is arranged on the rotary chassis. The frame is provided with a surrounding sleeve supporting rod, and the heat-insulating sleeve arranged on the heat-insulating sleeve supporting rod is arranged on the periphery of the test piece mold. The device combines engineering reality for preparation bituminous mixture test piece, reasonable in design, but the structure is comparatively complicated.
In summary, how to create a test device for manufacturing an asphalt concrete sample with a simple structure for simulating a construction process in the process of evaluating the performance of hydraulic asphalt concrete before the construction becomes a technical problem to be solved urgently by the technical staff in the field.
Disclosure of Invention
An object of the utility model is to provide a device of preparation asphalt concrete test piece that actual work progress, structure are simpler of laminating more before hydraulic engineering asphalt concrete construction.
In order to achieve the above purpose, the utility model adopts the following scheme: the hydraulic asphalt concrete construction workability testing device comprises an upper platform, a lower platform, a connecting rod, a vibrator, a sample barrel assembly, a counterweight assembly and a cantilever crane;
the lower platform is fixedly arranged on the ground, and the cantilever crane is fixedly arranged on the ground at one side of the lower platform;
the upper platform is fixedly arranged above the lower platform through a connecting rod, a first spring mounting seat and a second spring mounting seat are respectively arranged at the lower end of the upper platform and the upper end of the lower platform, a spring is arranged between the first spring mounting seat and the second spring seat, and the connecting rod penetrates through the first spring seat, the second spring seat and the spring to connect the upper platform and the lower platform together;
the vibrator is arranged between the upper platform and the lower platform and is fixedly arranged at the lower end of the upper platform;
the sample barrel assembly is fixedly arranged on the upper platform and comprises a detachable sample barrel and a sleeve, the detachable sample barrel is in a semi-cylindrical barrel shape, the two detachable sample barrels are connected through a fastener to form a complete cylindrical barrel shape, the sleeve is in a tubular shape, the inner diameter of the sleeve is consistent with that of the cylindrical barrel shape, and the sleeve is connected to the upper top ends of the two detachable sample barrels through the fastener;
a weight assembly is embedded in the top of the sample cartridge assembly.
Preferably, a first connecting plate is arranged on the side end face of the detachable sample cylinder, an outer step is arranged at the top end of the detachable sample cylinder, a second connecting plate is arranged on the outer step, through holes are formed in the first connecting plate and the second connecting plate, and a first bolt penetrates through the through holes in the first connecting plates of the two detachable sample cylinders and is locked through a first nut.
Preferably, a first elastic washer is disposed between the first nut and the first connection plate to prevent the first nut from loosening due to vibration.
Preferably, the bottom end of the sleeve is provided with an inner step, the inner step is matched with the outer step, the sleeve is convenient to position and mount, meanwhile, the sealing performance of the joint is improved, a third connecting plate is arranged on the outer circumference of the bottom end of the sleeve, a through hole is formed in the third connecting plate, and a second bolt penetrates through the through holes in the second connecting plate and the third connecting plate and is locked through a second nut.
Preferably, a second elastic washer is disposed between the second nut and the second connecting plate to prevent the second nut from loosening due to vibration.
As preferred, the counter weight subassembly includes the baffle, the pouring weight, weight and jib, the baffle is as counter weight subassembly's base, the middle part is provided with the blind hole, be provided with the internal thread in the blind hole, the pouring weight overlap joint is at the up end of baffle, the up end of pouring weight is arranged in proper order to the polylith weight, the middle part of pouring weight and weight all is provided with the through-hole, be used for passing the jib, the bottom of jib is provided with the internal screw thread of matching blind hole, the top of jib is provided with rings, be convenient for the cantilever to hoist on the one hand and hang the counter weight.
Preferably, an electromagnet is provided on the upper stage, and the sample cartridge assembly is fixed to the upper end surface of the upper stage by magnetic force.
Preferably, a heating plate is arranged in the wall of the detachable sample cylinder and used for heat preservation.
Preferably, the cantilever crane comprises a vertical column, a rotating track and a rotating arm, rotating electrical machines, electric block and extension arm, the stand is as the bearing structure that the cantilever hung, fixed mounting is subaerial in platform one side down, the one end fixed connection of swinging boom is in the upper end of stand, rotating electrical machines fixed mounting is in the upper end of stand, rotating electrical machines passes through gear drive, it rotates as the pivot to drive the axis of swinging boom use the stand, the lower extreme of swinging boom is provided with the track, electric block fixed mounting is on the track, be provided with the lifting hook that is used for lifting by crane the heavy object on the electric block, rotatory track fixed mounting is on being close to the position of stand upper end, the upper end fixed mounting of extension arm is on the swinging boom, the lower extreme of extension arm is provided with the pulley, the pulley can slide along rotatory track.
When the hydraulic asphalt concrete construction workability testing device is used, the vibrator keeps the vibration frequency fixed and unchanged, and the vibration time is changed or the total weight of the counterweight assembly is changed, so that the test is carried out. And placing the formed asphalt concrete sample block and the sample cylinder assembly indoors for natural cooling to room temperature. And then the sample cylinder assembly is dismantled, and the asphalt concrete sample block is taken out. And measuring the dry density of the asphalt concrete sample block to obtain the compactness. And drawing a curve of the compaction degree and the vibration time, and a curve of the compaction degree and the external total weight, and further evaluating the workability of the hydraulic asphalt concrete construction.
The utility model provides a pair of hydraulic engineering asphalt concrete construction workability test device compares with prior art, has following substantive characteristics and progress: the setting of detachable sample section of thick bamboo structure, the drawing of patterns of the asphalt concrete sample piece of being convenient for reduces the experimental degree of difficulty. The vibrator and the counterweight component are arranged, so that the structure is simple, and the vibration and the pressure of asphalt concrete in construction engineering can be better simulated. The asphalt concrete sample block prepared by the device provides theoretical basis and technical support for the construction of hydraulic asphalt concrete, and is convenient for selecting hydraulic asphalt concrete with good workability. The hydraulic asphalt concrete with good workability is easier to compact and saves compacting power under the same conditions, so that the device can provide guidance for improving engineering economic benefits.
Drawings
FIG. 1 is a perspective view of a workability testing apparatus for hydraulic asphalt concrete construction in an embodiment of the present invention;
FIG. 2 is a front view of FIG. 1;
FIG. 3 is a cross-sectional view at A-A of FIG. 2;
figure 4 is an assembled schematic view of the cartridge assembly 3.
Reference numerals: the device comprises an upper platform 1, a lower platform 2, a sample barrel assembly 3, a counterweight assembly 4, a cantilever crane 5, a connecting rod 6, a spring 7, a stand column 51, a rotating track 52, a rotating arm 53, a rotating motor 54, an electric hoist 55, an extending arm 56, a vibrator 8, a detachable sample barrel 31, a sleeve 32, an electromagnet 9, a partition plate 41, a weight 42, a weight 43, a suspender 44 and asphalt concrete 10.
Detailed Description
The following detailed description of embodiments of the present invention will be made with reference to the accompanying drawings.
The device for testing the workability of the hydraulic asphalt concrete construction shown in figures 1-4 is used for manufacturing asphalt concrete sample blocks. The device finally forms the asphalt concrete in the sample cylinder assembly 3 by simulating the vibration and pressure in the actual construction process. The maximum dry density of the formed asphalt concrete sample block is measured, the compaction degree of the sample block is calculated, the working performance of the asphalt concrete is reflected by analyzing the compaction degree, the workability of the hydraulic engineering asphalt concrete is further evaluated, and a theoretical basis and a technical support are provided for the construction of the hydraulic engineering asphalt concrete.
As shown in fig. 1 and fig. 2, the device for testing the workability of the hydraulic asphalt concrete construction comprises an upper platform 1, a lower platform 2, a sample cylinder assembly 3, a counterweight assembly 4 and a cantilever crane 5. The lower platform 2 is fixedly arranged on the ground. The upper platform 1 is fixedly arranged above the lower platform 2 through a connecting rod 6. The lower end of the upper platform 1 and the upper end of the lower platform 2 are respectively provided with a first spring mounting seat and a second spring mounting seat. A spring 7 is placed between the first spring mounting seat and the second spring seat. The connecting rod 6 passes through the first spring seat, the second spring seat and the spring 7 to connect the upper platform 1 and the lower platform 2 together. The spring 7 is used for buffering and shock absorption. The vibrator 8 is arranged between the upper platform 1 and the lower platform 2, is fixedly arranged at the lower end of the upper platform 1 and provides vibration perpendicular to the horizontal direction for the upper platform 1. A sample cartridge assembly 3 is placed on the upper platform 1 for containing the asphalt concrete to be tested. A weight assembly 4 is embedded in the top of the sample cartridge assembly 3 to provide pressure to the asphalt concrete in the sample cartridge assembly 3. The cantilever crane 5 is fixedly installed on the ground on one side of the lower platform 2 and used for hoisting the sample cylinder assembly 3, the balance weight assembly 4 and the like, and the auxiliary test is smoothly carried out.
The cantilever crane 5 includes a column 51, a rotating track 52, a rotating arm 53, a rotating motor 54, an electric hoist 55, and an extending arm 56. The upright 51 is used as a support structure of the cantilever crane 5 and is fixedly arranged on the ground at one side of the lower platform 2. One end of the rotating arm 53 is fixedly connected to the upper end of the column 51. A rotary motor 54 is fixedly mounted on the upper end of the column 51. The rotating motor 54 drives the rotating arm 53 to rotate about the axis of the column 51 through a gear transmission mechanism. The lower end of the rotating arm 53 is provided with a track. The electric block 55 is fixedly installed on the rail and can make reciprocating linear motion along the rail. The electric hoist 55 is provided with a lifting hook for lifting a heavy object. The rotating rail 52 is fixedly installed at a position near the upper end of the upright 51. The upper end of the extension arm 56 is fixedly mounted on the pivot arm 53. The lower end of the extension arm 56 is provided with a pulley. The pulley can slide along the rotation rail 52. The extension arm 56 serves to improve the structural strength of the rotating arm 53, so that the rotation is more stable.
As shown in fig. 3, the weight assembly 4 includes a spacer 41, a weight 42, a weight 43, and a boom 44. The bottom surface of the partition plate 41, which serves as a base for the weight assembly 4, serves as a partition for the asphalt concrete in the sample container assembly 3 and serves as a bearing surface. The middle of the partition plate 41 is provided with a blind hole. Internal threads are provided in the blind bore for attachment of the hanger bar 44. The weight 42 is overlapped on the upper end surface of the spacer 41. A plurality of weights 43 are placed on the upper end face of the weight 42. The weight 42 and the weight 43 are provided with through holes in the middle for passing through the suspension rod 44. The bottom end of the hanger bar 44 is provided with external threads that match the internal threads of the blind hole. The top end of the boom 44 is provided with a lifting ring, which facilitates on the one hand the lifting of the counterweight assembly 4 by the jib crane 5 and on the other hand the manual tightening of the boom 44.
The upper platform 1 is provided with an electromagnet 9 for fixing the sample cylinder assembly 3 on the upper end surface of the upper platform 1, so that vibration can be conveniently transmitted to asphalt concrete 10 in the sample cylinder assembly 3.
As shown in fig. 3 in conjunction with fig. 4, the cartridge assembly 3 includes a removable cartridge 31 and a sleeve 32. The detachable sample tube 31 has a semi-cylindrical barrel shape. A first connecting plate is provided on the side end surface of the detachable sample cartridge 31. The top of detachable sample section of thick bamboo 31 is provided with outer step. The outer step is provided with a second connecting plate. The first connecting plate and the second connecting plate are provided with through holes. The two removable sample cartridges 31 are connected by fasteners to form a complete cylindrical barrel shape. The first bolt passes through the through holes on the first connecting plates of the two detachable sample cylinders 31 and is locked by the first nut. Be provided with first elastic washer between first nut and the first connecting plate for prevent that first nut is because of the not hard up that the vibration arouses. The heating plate is arranged in the wall of the detachable sample cylinder 31 and used for keeping a certain temperature of the asphalt concrete 10.
The sleeve 32 has a tubular shape, and the inner diameter of the sleeve 32 is identical to the inner diameter of the cylindrical barrel. The bottom end of the sleeve 32 is provided with an internal step. The cooperation of the inner and outer steps facilitates positioning and installation of the sleeve 32 while improving the seal at the seam. A third connecting plate is provided on the outer circumference of the bottom end of the sleeve 32. The third connecting plate is provided with a through hole. The sleeve 32 is connected to the upper top ends of the two removable sample cartridges 31 by fasteners. And the second bolt passes through the through holes in the second connecting plate and the third connecting plate and is locked by the second nut. And a second elastic washer is arranged between the second nut and the second connecting plate and used for preventing the second nut from loosening caused by vibration.
The maximum outer diameter of the weight assembly 4 is slightly less than the inner diameter of the sleeve 32 to facilitate insertion of the weight assembly 4 into the interior of the cartridge assembly 3.
In use, the cantilever crane 5 positions the sample cartridge assembly 3 on the upper platform 1. The electromagnet 9 is energized to magnetically fix the sample cartridge assembly 3 to the upper platform 1. The cantilever crane 5 assists in pouring the asphalt concrete 10 into the sample cartridge assembly 3 and then hoists the weight assembly 4 embedded in the sample cartridge assembly 3. The vibrator 8 is turned on and remains on for a certain time. This device is keeping under the fixed unchangeable condition of vibration frequency, changes the vibration time or changes the gross weight of counter weight subassembly 4 and then tests.
And placing the formed asphalt concrete sample block and the sample cylinder assembly 3 indoors for natural cooling to room temperature. The sample cartridge assembly 3 is then removed and the asphalt concrete sample block is removed. And measuring the dry density of the asphalt concrete sample block to obtain the compactness. And drawing a curve of compaction degree and vibration time, a curve of compaction degree and external total weight, and further evaluating the workability of the rolling hydraulic asphalt concrete construction.
Wherein the frequency provided by the vibrator 8 is 40-60Hz and the amplitude is 0-2 mm. The weight assembly 4 provides a minimum pressure of 14kpa to the asphalt concrete.
The present invention is not limited to the specific technical solutions described in the above embodiments, and other embodiments can be provided in addition to the above embodiments. It should be understood by those skilled in the art that any modifications, equivalent substitutions, improvements and the like that are made within the spirit and principle of the present invention are within the scope of the present invention.
Claims (9)
1. A hydraulic asphalt concrete construction workability test device is characterized by comprising an upper platform, a lower platform, a connecting rod, a vibrator, a sample barrel assembly, a counterweight assembly and a cantilever crane;
the lower platform is fixedly arranged on the ground, and the cantilever crane is fixedly arranged on the ground at one side of the lower platform;
the upper platform is fixedly arranged above the lower platform through a connecting rod, a first spring mounting seat and a second spring mounting seat are respectively arranged at the lower end of the upper platform and the upper end of the lower platform, a spring is arranged between the first spring mounting seat and the second spring seat, and the connecting rod penetrates through the first spring seat, the second spring seat and the spring to connect the upper platform and the lower platform together;
the vibrator is arranged between the upper platform and the lower platform and is fixedly arranged at the lower end of the upper platform;
the sample cylinder assembly is fixedly arranged on the upper platform and comprises a detachable sample cylinder and a sleeve, the detachable sample cylinder is in a semi-cylindrical barrel shape, the two detachable sample cylinders are connected through a fastener to form a complete cylindrical barrel shape, the sleeve is in a tubular shape, the inner diameter of the sleeve is consistent with that of the cylindrical barrel shape, and the sleeve is connected to the upper top ends of the two detachable sample cylinders through the fastener;
the weight assembly is embedded in the top of the sample cartridge assembly.
2. The apparatus for testing workability in hydraulic asphalt concrete construction according to claim 1, wherein a first connecting plate is disposed on a side end face of the detachable sample cylinder, an outer step is disposed on a top end of the detachable sample cylinder, a second connecting plate is disposed on the outer step, through holes are disposed on the first connecting plate and the second connecting plate, and the first bolt passes through the through holes on the first connecting plates of the two detachable sample cylinders and is locked by the first nut.
3. The apparatus for testing workability in hydraulic asphalt concrete construction according to claim 2, wherein a first elastic washer is disposed between the first nut and the first connection plate.
4. The device for testing the workability of hydraulic asphalt concrete construction according to claim 2, wherein the bottom end of the sleeve is provided with an inner step, the outer circumference of the bottom end of the sleeve is provided with a third connecting plate, the third connecting plate is provided with a through hole, and the second bolt passes through the through holes on the second connecting plate and the third connecting plate and is locked by a second nut.
5. The apparatus for testing the workability in the construction of hydraulic asphalt concrete according to claim 4, wherein a second elastic washer is arranged between the second nut and the second connecting plate.
6. The hydraulic asphalt concrete construction workability test device according to claim 1, wherein the counterweight assembly comprises a partition plate, a weight, weights and a hanging rod, the partition plate is used as a base of the counterweight assembly, a blind hole is formed in the middle of the partition plate, internal threads are formed in the blind hole, the weight is lapped on the upper end face of the partition plate, a plurality of weights are sequentially arranged on the upper end face of the weight, through holes are formed in the middle of the weight and the middle of each weight, external threads matched with the internal threads of the blind hole are formed in the bottom end of the hanging rod, and a hanging ring is arranged at the.
7. The apparatus for testing the workability in the construction of hydraulic asphalt concrete according to claim 1, wherein the upper platform is provided with an electromagnet, and the sample cylinder assembly is fixed on the upper end surface of the upper platform by magnetic force.
8. The apparatus for testing the workability in hydraulic asphalt concrete construction according to claim 1, wherein a heating plate is arranged in the wall of the detachable sample cylinder.
9. The device for testing the workability of hydraulic asphalt concrete construction according to claim 1, wherein the cantilever crane comprises an upright post, a rotating track, a rotating arm, a rotating motor, an electric hoist and an extension arm, the upright post is used as a supporting structure of the cantilever crane and is fixedly installed on the ground on one side of the lower platform, one end of the rotating arm is fixedly connected to the upper end of the upright post, the rotating motor is fixedly installed at the upper end of the upright post, the lower end of the rotating arm is provided with a track, the electric hoist is fixedly installed on the track, the electric hoist is provided with a lifting hook, the rotating track is fixedly installed on a position close to the upper end of the upright post, the upper end of the extension arm is fixedly installed on.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021021561.7U CN212083439U (en) | 2020-06-06 | 2020-06-06 | Hydraulic asphalt concrete construction workability test device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021021561.7U CN212083439U (en) | 2020-06-06 | 2020-06-06 | Hydraulic asphalt concrete construction workability test device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN212083439U true CN212083439U (en) | 2020-12-04 |
Family
ID=73558044
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202021021561.7U Expired - Fee Related CN212083439U (en) | 2020-06-06 | 2020-06-06 | Hydraulic asphalt concrete construction workability test device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN212083439U (en) |
-
2020
- 2020-06-06 CN CN202021021561.7U patent/CN212083439U/en not_active Expired - Fee Related
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN200986503Y (en) | Vibration compaction instrument | |
| CN209356334U (en) | A kind of elastic modulus of concrete experimental rig | |
| CN203069467U (en) | Surface vibrating compaction tester | |
| CN209745511U (en) | Pipeline resonance fatigue test bench | |
| CN208984463U (en) | Pavement material intensity experimental rig | |
| CN212083439U (en) | Hydraulic asphalt concrete construction workability test device | |
| CN106680085A (en) | System and method for testing aging characteristics of bolt system on basis of creep testing machine | |
| CN216082337U (en) | Building material intensity check out test set | |
| CN114397432A (en) | Concrete structure surface crack detection device | |
| CN209508970U (en) | A kind of construction static pile press | |
| CN219285096U (en) | Building engineering quality detection device | |
| CN207066657U (en) | A kind of simple lever consolidation apparatus for supporting balancing method expansive force to test | |
| CN115233750B (en) | Steel construction assembled basis short column measurement positioner | |
| CN215051917U (en) | On-spot compactness test pit reinforcement device | |
| CN114111694B (en) | Anti-slide pile deformation monitoring device and failure early warning system | |
| CN112345325B (en) | Vibrating table method experimental device and method for soil dry density test | |
| CN201458625U (en) | Steel wire rope speed measuring device of main hoisting machine on pile frame | |
| CN211504651U (en) | Fixed suspension system and paver screed testing device | |
| CN106290079B (en) | Coarse aggregate angularity testing method and testing device | |
| CN219320953U (en) | Engineering structure safety monitoring test demonstration platform | |
| CN210863081U (en) | Material-saving type cement stabilized base layer construction test system | |
| CN218157146U (en) | Jolt ramming device for cement and raw materials | |
| CN220057567U (en) | Intensity detector | |
| CN215004382U (en) | Engineering is supervised and is detected native device with road bed compactness | |
| CN213233378U (en) | Roadbed compactness detection soil sampling device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20201204 Termination date: 20210606 |