A device and method for measuring physical and mechanical properties of self-compacting solidified soil

Abstract

The application discloses a kind of self-compacting solidified soil physical mechanics performance determination device and determination method, determination device includes stirring module, slump determination module, sample preparation module, setting time determination module, maintenance module, stripping module and unconfined compressive strength determination module;Stirring module includes the stirring box with discharge pipe and feed inlet, slump determination module includes slump barrel, pulley, vertical slide rail and slump determination unit, stirring module is connected with slump determination module by discharge pipe, sample preparation module is connected with slump determination module by pouring table;When the application is determined, soil sample stirring, slump determination, setting time determination and sample preparation are sequentially carried out, and soil sample flows into slump barrel from stirring module through discharge pipe, the bottom of slump barrel is attached to determination plate by the way of inserting support, the speed of slump barrel rising is controlled by lifting device, and the application improves the accuracy of determination data and the fluency between tests.

Description

Technical Field

[0001] This invention relates to solidified soil in the fields of soil modification, foundation pit backfilling, and road construction, and particularly to a device and method for measuring the physical and mechanical properties of self-compacting solidified soil. Background Technology

[0002] With the increasing popularity of underground space development, a large amount of engineering waste soil lacks planning. In recent years, self-compacting soil technology has been widely used. It utilizes engineering waste soil to fully mix with water and solidifying agent to form a soil body with a certain strength and fluidity before backfilling. This effectively solves the problems of difficult disposal of engineering waste soil and difficulties in backfilling various projects. However, because this technology is relatively new, strength and fluidity-related tests are mostly conducted using relevant specifications for concrete, cement soil, etc., which has limitations.

[0003] Self-compacting solidified soil (SCS) is a novel fluid filling material formed by thoroughly mixing waste soil, water, and a solidifying agent. To ensure its successful application in practical engineering projects such as foundation pit backfilling and roadbed construction, it is necessary to measure its physical and mechanical properties, including its spread, unconfined compressive strength, and setting time. However, conducting fluidity tests using existing standards consumes a large amount of test materials. Thorough mixing of these materials presents challenges to the testing process, and the soil used in the fluidity tests is often wasted due to a lack of reuse.

[0004] After sample preparation and curing, demolding is required. However, there are many types of molds available, and the quality of demolding significantly affects strength measurement. Molds of the same shape often correspond to a specific demolding device. If a suitable demolding device is unavailable, manual demolding can easily damage the sample, leading to inaccurate strength measurements. When selecting testing equipment according to existing standards for strength testing of self-compacting soil, given that current research on strength testing of self-compacting soil is not yet comprehensive, and considering the correlation between the strength of self-compacting soil and the type of curing agent used, and the wide variety of curing agents available, the unconfined compressive strength range of self-compacting soil is difficult to determine. Using traditional soil unconfined compressive strength testing devices will result in insufficient measurement range, making accurate measurements difficult.

[0005] Secondly, the setting time of self-compacting soil is also an important physical indicator, which significantly affects construction efficiency. An excessively long setting time makes it difficult to guarantee the strength of the backfill soil and slows down the construction progress. After adding a curing agent, the setting time of the self-compacting soil differs significantly from that of the curing agent itself, without a clear pattern. Therefore, given the current lack of suitable equipment for testing the relevant physical properties of self-compacting soil, there is an urgent need for a device for testing the physical and mechanical properties of self-compacting soil, and for providing a test method for related experiments. Summary of the Invention

[0006] Purpose of the invention: To address the shortcomings of current testing equipment for self-compacting soil, which lacks corresponding testing devices and results in soil waste during the testing process, this invention provides a device and method for measuring the physical and mechanical properties of self-compacting soil. By controlling the rising speed of the slump bucket through a lifting device, the seepage at the bottom of the slump bucket is improved, thereby increasing the accuracy and smoothness of the slump measurement test. Furthermore, by fixing molds of different sizes through telescopic rods, the flexibility of the test is improved, the continuity of the test is ensured, and the testing efficiency is increased.

[0007] Technical solution: The self-compacting solidified soil physical and mechanical property testing device of the present invention includes a mixing module, a slump testing module, a sample preparation module, a setting time testing module, a curing module, a demolding module, and an unconfined compressive strength testing module;

[0008] The mixing module includes a mixing tank with a discharge pipe and a feed inlet, a mixing assembly on top of the mixing tank, a valve on the discharge pipe, and a telescopic mixing rod at the bottom of the mixing tank.

[0009] The slump measurement module includes a slump bucket, a pulley, a vertical slide rail, and a slump measurement unit. The slump bucket has a first groove on both sides, and the pulley has a second groove on its side. A bracket is inserted into the first groove and the second groove. The pulley moves along the vertical slide rail, and a lifting device is connected to the bottom of the pulley.

[0010] The slump measuring unit includes a measuring plate with a level bubble and a central hole and groove. There is a support under the measuring plate. The end of the measuring plate is equipped with an upper circumference plate and a lower folding plate. A leveling component is installed on the lower folding plate. A soil sample control tube is screwed to the bottom of the slump bucket. One end of the soil sample control tube is screwed into the central hole.

[0011] The sample preparation module includes a pouring device and a vibrating fork; the pouring device includes a funnel with a diverter tube; one end of the diverter tube leads to the final setting time determination module, and the other end of the diverter tube is connected to a storage bottle; a servo motor is connected above the storage bottle, and a pouring pipe is connected below it; a mold is connected below the pouring pipe; shrink clamps are on both sides of the mold, and a conveyor belt is at the bottom of the mold.

[0012] The demolding module includes telescopic rods located at the bottom and on both sides. The ends of the telescopic rods on both sides are equipped with clamps to hold the mold in place, and the telescopic rod at the bottom extends into the mold.

[0013] The mixing module is connected to the slump measuring module via a discharge pipe, the sample preparation module is connected to the slump measuring module via a pouring platform, and the final setting time measuring device is connected to the sample preparation module via a diversion pipe.

[0014] The unconfined compressive strength testing module includes a load sensor, a displacement sensor, a screw lifting device, and a data acquisition instrument. The load sensor and displacement sensor are connected to the data acquisition instrument, and the displacement sensor is distributed on the screw lifting device.

[0015] The stirring assembly includes a servo motor, a telescopic rod, and rotating blades, with the rotating blades fitted onto the telescopic rod.

[0016] The leveling assembly includes a support and bolts passing through the lower folding plate, with leveling nuts screwed onto the bolts.

[0017] The maintenance module includes a water storage tank, a humidifier, a tray for placing molds, a temperature sensor, and a humidity sensor. Above the water storage tank are a filter and a heating element.

[0018] A humidifier consists of a liquid reservoir, a humidification tube, and a nozzle. The humidification tube controls the opening and closing of the nozzle.

[0019] The bottom telescopic rod is equipped with a pad that extends into the mold. The bottom telescopic rod drives the pad to extend into the mold and demold the soil sample from the mold.

[0020] The ends of the telescopic rod are provided with grooves, and the clamps and washers are provided with protrusions that engage with the grooves.

[0021] The slump bucket has connecting blocks on both sides, and the side of the connecting blocks has a first groove.

[0022] The method for determining the physical and mechanical properties of self-compacting solidified soil according to the present invention is implemented by a device for determining the physical and mechanical properties of self-compacting solidified soil, and the method includes the following steps:

[0023] (1) After weighing the soil sample, water and curing agent, pour them into the mixing tank through the feed inlet, control the telescopic rod and rotating blade of the mixing device to move up and down, and rotate and mix until a soil sample that has formed self-compacting and solidified soil is formed.

[0024] (2) Insert one end of the bracket into the first groove on both sides of the slump bucket, and insert the other end of the bracket into the second groove of the pulley. Adjust the lifting device to drive the pulley to move along the vertical slide rail until the slump bucket with the soil sample control tube is stuck in the groove of the measuring plate. Adjust the leveling nut to be horizontal using the level bubble.

[0025] (3) Open the valve and the soil sample flows into the slump bucket through the discharge pipe. Control the telescopic stirring rod to insert into the slump bucket. After the soil sample fills the slump bucket, remove the discharge pipe and the telescopic stirring rod. Control the lifting device to move upward until the soil sample flows to a standstill. Read the spread data of the soil sample according to the measuring plate.

[0026] (4) Adjust the shrink clamp and clamp the mold, close the valve in the diversion pipe leading to the setting time measurement module, unscrew the soil sample control tube, and let the soil sample flow into the storage bottle through the funnel, and then into the mold through the pouring pipe. Move the vibrating fork to vibrate on both sides of the mold. After the mold is poured, rotate the storage bottle and move the conveyor belt through the servo motor to pour the next set of molds.

[0027] (5) Open the valve to the setting time measurement module. The remaining soil sample in the slump bucket flows into the setting time measurement module. Start timing and record the initial setting and final setting times of the soil sample.

[0028] (6) Move the mold with the poured soil sample to the tray of the curing module and set the temperature and humidity;

[0029] (7) After the soil sample is cured, take out the mold and place it on the pad of the demolding module. Install the clamp on the telescopic rods on both sides and clamp the mold. Install the pad on the telescopic rod at the bottom. Adjust the telescopic rod at the bottom to lift it up. Push the soil sample out of the mold and place it in the curing module.

[0030] (8) After curing to the specified age, the soil sample is taken out from the curing module and placed on the spiral lifting device of the unconfined compressive strength test module. It is raised to the top of the soil sample and stops after contacting the load sensor. After the readings of the load sensor and displacement sensor are cleared to zero, the spiral lifting device is controlled to rise. The data acquisition instrument records the strain data measured by the load sensor and the strength data measured by the displacement sensor during the test.

[0031] Beneficial effects: Compared with the prior art, the present invention has the following advantages:

[0032] (1) This invention integrates seven functions into one: mixing of self-compacting soil, slump measurement, setting time measurement, sample preparation, sample curing, sample demolding, and unconfined compressive strength measurement. The four test modules of soil sample mixing, slump measurement, setting time measurement, and sample preparation are interconnected. Compared with the prior art, it realizes functional centralization, increases the fluidity of the test, and improves the test efficiency.

[0033] (2) Multiple mixing components are distributed above the mixing tank of the present invention. The mixing components fully mix the soil sample by extending and retracting. The lower part of the mixing tank is inclined, and the soil sample slides towards the middle under the mixing action, which reduces the situation where the soil sample is easy to accumulate at the corner and is difficult to mix.

[0034] (3) The self-compacting solidified soil flows from the mixing module into the slump bucket through the discharge pipe. Compared with the existing technology of direct dumping, it reduces the occurrence of soil samples piling up into blocks and large gaps between soil blocks after being poured in. At the same time, the telescopic mixing rod of the present invention further compacts the soil in the slump bucket and reduces soil voids.

[0035] (4) The slump bucket of the present invention is equipped with connecting blocks on both sides. By inserting the bracket, the bottom of the slump bucket is made to fit with the measuring plate, and the air between the bracket and the measuring plate is discharged. This prevents water from seeping out after the soil sample is poured into the slump bucket. Moreover, when the slump is measured, the speed at which the slump bucket rises is controlled by the lifting device. Compared with the prior art, this method saves manpower by pressing the slump bucket, improves the water seepage at the bottom of the slump bucket, and makes the slump bucket rise at a uniform speed, thereby improving the accuracy of the slump measurement test.

[0036] (5) After the bottom threaded cylinder of the slump measuring unit of the present invention is unscrewed, the soil that has completed the slump measuring test will seep into the next process, which improves the smoothness of the test.

[0037] (6) The sample preparation module of the present invention pours the soil sample into the mold through the pouring pipe. The already relatively dense soil in the mold is further compacted under the action of the vibrating fork, which eliminates the voids and reduces the error of the parallel test of self-compacting solidified soil. In addition, the molds used for the preparation of self-compacting solidified soil are available in various sizes, which avoids the difficulty of the molds being stuck into the fixing device on the conveyor belt due to their varying sizes.

[0038] (7) The shrinkage clamp of the present invention can be used not only for the preparation of unconfined compressive strength test specimens of self-compacting soil of the present invention by adjusting the shrinkage diameter, but also for the preparation of test specimens for direct shear test and permeability test. Only the ring cutter is inserted into the shrinkage clamp, which further improves the utilization rate of soil material and expands the application range.

[0039] (8) The maintenance module of the present invention uses a temperature sensor, a humidity sensor, a spray device and a heating pipe to jointly control the temperature and humidity, introduces a water storage tank to reduce changes in ambient temperature and humidity, and a filter screen to ensure the quality of the water in the water storage tank and reduce impurities.

[0040] (9) Compared with the prior art, the demolding module of the present invention is simpler. It fixes the mold by means of rod extension and retraction, and the joint used for fixing is also a splicing joint, which can flexibly deal with the situation of mold size variation.

[0041] (10) The unconfined compressive strength measuring module of the present invention improves the measurement range of unconfined compressive strength. The existing unconfined compressive strength measuring instruments have a range of 2MPa, which is lower than the unconfined compressive strength of some self-compacting soils with high curing agent content. The range of the present invention is increased to 3MPa to meet the requirements of the unconfined compressive strength of self-compacting soils. Furthermore, the displacement sensor of the present invention is located at the bottom and both sides of the helical support, and the error is further reduced by taking the average value. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the structure of the self-compacting solidified soil physical and mechanical property testing device of the present invention;

[0043] Figure 2 This is a schematic diagram of the acrylic plate frame structure in the measuring device of the present invention;

[0044] Figure 3 This is a schematic diagram of the slump measuring unit of the present invention;

[0045] Figure 4 This is a schematic diagram of the casting device of the present invention;

[0046] Figure 5 This is a schematic diagram of the demolding module assembly of the present invention. Detailed Implementation

[0047] like Figures 1 to 5 As shown, the self-compacting solidified soil physical and mechanical property testing device of the present invention includes a mixing module 1, a slump testing module 2, a sample preparation module 3, a setting time testing module 4, a curing module 5, a demolding module 6, and an unconfined compressive strength testing module 7. The mixing module 1 includes a mixing tank 17 with a discharge pipe 13 and a feed inlet 12. A mixing assembly 11 is located above the mixing tank 17. The discharge pipe 13 has a valve 14, and a telescopic mixing rod 15 is located at the bottom of the mixing tank 17. An inclined brace 16 is also provided at the bottom of the mixing tank 17.

[0048] The slump measurement module 2 includes a slump bucket 21, a pulley 23, a vertical slide rail 24, and a slump measurement unit 27. The slump bucket 21 has first grooves 212 on both sides, and the pulley 23 has a second groove 231 on its side. A bracket 26 is inserted into the first groove 212 and the second groove 231. The wheel of the pulley 23 is embedded in the vertical slide rail 24, and the pulley 23 moves within the vertical slide rail 24. A lifting device 22 is connected to the bottom of the pulley 23. In this embodiment, the bracket 26 is made of acrylic.

[0049] The demolding module 6 includes telescopic rods 61 located at the bottom and on both sides. The ends of the telescopic rods 61 on both sides are provided with clamps 62 that engage with the mold 35, and the bottom of the telescopic rod 61 at the bottom is provided with a pad 63 that extends into the mold 35.

[0050] The unconfined compressive strength testing module 7 includes a load sensor 71, a displacement sensor 72, a screw lifting device 73, and a data acquisition instrument 74. The load sensor 71 and the displacement sensor 72 are connected to the data acquisition instrument 74, and the displacement sensor 72 is located on the screw lifting device 73.

[0051] The mixing module 1 is connected to the slump measuring module 2 through the discharge pipe 13. The sample preparation module 3 is connected to the slump measuring module 2 through the pouring platform 31. The final setting time measuring device 4 is connected to the sample preparation module 3 through the diversion pipe 312. The curing module 5 and the unconfined compressive strength device 7 are located on both sides of the sample preparation module 3. The demolding module 6 is located below the setting time measuring module 4.

[0052] The mixing module 1 contains multiple mixing components 11, each including a servo motor 111, a telescopic rod 112, and a rotating blade 113. The rotating blade 113 is sleeved on the telescopic rod 112. The mixing tank 17 is provided with multiple feed inlets 12. Different materials are poured into different feed inlets 12 in the same test. The lower side of the mixing tank 17 is a slope with a set angle and the inner wall is smooth. The mixed soil sample flows into the slump bucket 21 through the discharge pipe 13. The inner diameter of the discharge pipe 13 is ≥3cm.

[0053] The slump cone 21 has openings at the top and bottom, with diameters of 10cm and 20cm respectively, and a height of 30cm. The surface roughness of the inner wall is ≤Ra3.2. Connecting blocks are installed on the lower sides of the slump cone 21. In this embodiment, the connecting blocks are rubber blocks 211, and a first groove 212 is formed on the outer side of the rubber block 211. A second groove 231 is also formed on the inner side of the pulley 23. The dimensions of the inner groove 231 of the pulley 23 and the outer groove 212 of the rubber block 211 ensure that both ends of the acrylic support can be inserted into it.

[0054] The slump measuring unit 27 is located below the slump bucket 21. The slump measuring unit 27 includes a measuring plate 271 with a level bubble 28 and a central hole and groove, a soil sample control cylinder 272, a support 273, an upper surrounding plate 274, and a lower folding plate 275. The soil sample control cylinder 272 is threaded onto the measuring plate 271, and the measuring plate 271 is fixed to the support 273. The measuring plate 271 has dimensions of 80cm*80cm*1cm, an upper surface roughness ≤Ra6.3, a central hole size consistent with the diameter of the soil sample control cylinder 272, and threads on the inner side of the measuring plate 271 with the same texture as the soil sample control cylinder 272.

[0055] The measuring plate 271 has an upper circumferential plate 274 and a lower folding plate 275 at its end. A leveling component 25 is installed on the lower folding plate 275. A soil sample control tube 272 is threadedly connected to the bottom of the slump bucket 21. One end of the soil sample control tube 272 is threadedly connected to the center hole of the measuring plate 271.

[0056] The leveling assembly 25 includes a bolt 251 passing through the lower folding plate 275, a leveling nut 252, and a support 253. The leveling nut 252 is screwed onto the bolt 251. Each leveling assembly 25 has two leveling nuts 252, located on the upper and lower sides of the lower folding plate 275 of the slump meter 27, respectively. The leveling nuts 252 are adjusted according to the observed level bubble 28.

[0057] The sample preparation module 3 includes a pouring device 31 and a vibrating fork 34; the pouring device 31 connects the slump measurement module 2 and the sample preparation module 3. The pouring device 31 includes a funnel 311 with a diversion pipe 312, a valve 313, a servo motor 314, a storage bottle 315, and a pouring pipe 316. The upper end of the diversion pipe 312 is in close contact with the funnel 311, and then splits into two streams, one stream leading to the storage bottle 315, and the other stream leading to the final setting time measurement module 4. Each diversion pipe 312 is equipped with a valve 313. The storage bottle 315 is connected to the servo motor 314 at the top and to the pouring pipe 316 at the bottom, and the pouring pipe 316 is inserted into the storage bottle 315. A mold 35 is connected to the bottom of the pouring pipe 316; the mold 35 has shrink clamps 33 on both sides and a conveyor belt 32 at the bottom.

[0058] The upper enclosure plate 274 and the lower folding plate 275 are both peripheral structures of the slump measuring unit 27. The upper enclosure plate 274 is used to prevent the flow of fluid soil, and the lower folding plate 275 is used to support the slump measuring unit 27. The slump measuring unit 27 is used to measure the spread of the soil.

[0059] The curing module 5 includes a housing, a humidifier 51, a tray 52, a temperature sensor 53, and a humidity sensor 54. The bottom of the housing has a water storage tank 57, and above the water storage tank 57 are a filter screen 56 and a heating element 58. The inner wall of the curing module 5 has multiple grooves 55. The tray 52 is inserted into the grooves 55 on both sides to place the curing sample. The humidifier 51 and the humidity sensor work together to control the humidity of the curing module. The humidifier 51 includes a liquid storage bottle 511, a humidification tube 512, and a nozzle 513. The liquid storage bottle 511 is placed outside the curing module, and the humidification tube 512 is placed inside the curing module. The humidification tube 512 buffers the water storage, and the nozzle 513 is controlled to close based on feedback from the humidity sensor 54. The heating element 58 and the temperature sensor 53 work together to control the temperature of the curing module. The temperature sensor 53 monitors the temperature inside the module and controls the on / off state of the heating element 58. The bottom of the maintenance module 5 is equipped with a water storage tank 57. Water in the air enters the tank through the filter screen 56, which controls the temperature and humidity inside the module to prevent significant changes.

[0060] like Figure 5As shown, the demolding module 6 is equipped with three telescopic rods 61. Each telescopic rod 61 has a groove 64 at its end, and the groove 64 is threaded. The clamps 62 and the gaskets 63 have protrusions at their ends that engage with the grooves, and the protrusions are also threaded. The clamps 62 and the gaskets 63 are engaged in the grooves 64. The type of clamp 62 is determined according to the size of the mold 35 to ensure that the clamps 62 are in contact with the mold 35. The size of the gaskets 63 is determined by the bottom diameter of the mold 35, and the gaskets 63 extend into the mold 35 and fit against the inner wall of the mold 35.

[0061] During demolding, first screw the clamp 62 and the gasket 63 into the telescopic rod 61 for fixation. Then, place the sample preparation mold 35 on the gasket 63, at which point the telescopic rod 61 at the bottom of the gasket 63 is fixed. Drive the telescopic rods 61 on both sides to the mold 35 until the clamps 62 of the telescopic rods 61 on both sides clamp the mold 35. Fix the telescopic rods 61 on both sides, and then control the telescopic rod 61 at the bottom of the gasket 63 to move upward, demolding the soil sample from the mold 35.

[0062] The load sensor 71 and displacement sensor 72 of the unconfined compressive strength testing module 7 are connected to the data acquisition instrument 74 via wires 75. The data acquisition instrument 74 controls the lifting rate of the screw lifting device 73, reads the load magnitude of the load sensor 71, and reads the displacement strain magnitude of the displacement sensor 72. The load sensor 71 has a range ≤3MPa, and the displacement sensor 72 is arranged on both sides of the screw lifting device 73 with an accuracy of 0.001mm. The screw lifting device 73 has multiple strain rate settings, controlled from 0.5mm / min to 4mm / min, and is electrically controlled.

[0063] The method for determining the physical and mechanical properties of self-compacting solidified soil according to the present invention includes the following steps:

[0064] (1) The weighed soil sample, water and one or more curing agents are mixed in proportion. The total mass of soil, water and curing agent required for the test is 10 kg. At the beginning of the test, the weighed soil sample, water and curing agent are poured into the mixing tank 17 through different feed ports 12. After the materials are poured into the mixing tank 17, the mixing component 11 is started and the rotation speed of the mixing component 11 is controlled at 60 r / min-120 r / min. In the early stage of the test, the rotating blades 113 of the mixing component 11 are close to the bottom of the mixing tank 17 but do not contact it. After all the materials are poured into the mixing tank 17, the telescopic rod 112 of the mixing component 11 is controlled to control the rotating blades 113 to move up and down. The mixture is stirred for 5 minutes at a rotation speed of 60 r / min-120 r / min to form self-compacting solidified soil.

[0065] (2) Screw the soil sample control tube 272 into the bottom of the slump bucket 21. Insert one end of the support 26 into the first groove on both sides of the slump bucket 21 and the other end of the support 26 into the second groove of the pulley 23. Adjust the lifting device 22 to drive the pulley 23 to move along the vertical slide rail 23 until the support 26 contacts the measuring plate 271, so that the slump bucket 21 is stuck in the groove of the measuring plate 271, so that the slump bucket 21 is located in the center of the measuring plate 271 and does not move. This is to prevent water from flowing out of the self-compacted soil in the subsequent test and affecting the actual mix ratio. After the position of the slump bucket 21 is adjusted, adjust the leveling nut 252 to be horizontal according to the level bubble 28.

[0066] (3) Open valve 14. The soil sample of the self-compacting solidified soil after mixing flows into the slump bucket 21 through the discharge pipe 13. While the soil sample is flowing into the slump bucket 21, control the telescopic stirring rod 15 to insert and tamp it into the slump bucket 21 to prevent the soil sample from accumulating and not adhering to the inner wall of the slump bucket 21. After the slump bucket 21 is filled, remove the discharge pipe 13 and the stirring rod 15. Control the lifting device 22 to push the pulley 23 to move upward 30cm along the vertical slide rail 24. The upward movement process is controlled to be completed in 10s. When the lifting device 22 pushes the pulley 23 to move upward, the slump bucket 21 moves upward with the lifting device 22. At this time, the soil sample originally placed in the slump bucket 21 will collapse and cannot maintain its original bucket shape. It will flow on the measuring plate 271. The surface of the measuring plate 271 is printed with scales to make it easy to visually display the expansion of the soil sample. After letting the soil sample stand for 1 minute until it stops flowing, read the soil sample spread data according to the measuring plate 271 and the scale.

[0067] (4) Adjust the shrink clamp 33 to clamp the mold 35, close the valve in the diversion pipe 312 leading to the setting time measurement module 4, and unscrew the soil sample control tube 272. The function of the soil sample control tube 272 is to keep it in a tightened state during the slump test to prevent soil from flowing out. After the slump test is completed, unscrew the soil sample control tube 272, and the soil sample will flow down. The soil sample flows into the storage bottle 315 through the funnel 311, and then into the mold 35 through the pouring pipe 316. After each third of the soil sample has flowed into the mold 35, move the vibrating fork 34 to both sides of the mold 35 and vibrate it left and right to compact the soil sample in the mold 35. After one set of molds 35 has been poured, the next set of molds 35 is poured by rotating the storage bottle 315 and moving the conveyor belt 32 through the servo motor 314.

[0068] (5) After the soil sample in mold 35 is prepared, there is still soil sample left in slump bucket 21. Close the valve on the upper side of the servo motor, open the valve to the setting time measurement module 4, the soil sample flows into the setting time measurement module 4, start timing, and record the initial setting and final setting time of the soil sample.

[0069] (6) Wipe the outer surface of the mold 35 after the soil sample has been poured, and move it manually to the tray inside the curing box. Move it to the tray 52 inside the curing module 5, and set the temperature and humidity conditions required for this curing.

[0070] (7) Figure 5 As shown, after the soil sample has been cured for 36-48 hours, the mold 35 containing the soil sample is removed and placed on the pad 63 of the demolding module 6. The position of the pad is raised by the telescopic rod to expel the soil sample from the mold. A clamp 62 suitable for this mold 35 is selected and installed onto the telescopic rod 61, or screwed into the telescopic rod 61. A pad 63 with the same bottom diameter as this mold 35 is selected and installed. The length of the telescopic rod 61 is adjusted so that the clamp 62 clamps the mold 35. The bottom telescopic rod 61 is adjusted to lift the pad 63 upwards, pushing the soil sample out of the mold 35. The sample is then placed back into the curing module 5 for further curing.

[0071] (8) After curing to the specified age, such as 3 days, 7 days, 14 days, 28 days, 56 days and 90 days, the soil sample is taken out from the curing module 5 and placed in the center of the spiral lifting device 73 of the unconfined compressive strength test module 7. After rising to the position where the top of the soil sample contacts the load sensor 71, it stops. After clearing the readings of the load sensor 71 and the displacement sensor 72 in the data acquisition instrument 74, the spiral lifting device 73 is controlled to rise at the specified rate. The data acquisition instrument 74 records the strain data and strength data during the test. The strength data is read by the load sensor 71 and the strain data is read by the displacement sensor 72. The strain data is the average value of the two displacement sensors 72.

[0072] The strength here refers to the unconfined compressive strength. The soil sample, after being demolded and cured to the specified age, is placed on the platform of the screw lifting device 73. When the screw lifting device 73 is controlled to move upward, when the top of the soil sample contacts the bottom platform of the load sensor 71, the reading of the displacement sensor 72 is cleared to zero. Then, the sample rises at a certain strain control rate, and the readings of the displacement sensor 72 and the load sensor 71 are recorded at the same time.

[0073] Before step (7), the parts involved in the test in the stirring module 1, slump measurement module 2, sample preparation module 3 and setting time measurement module 4 are wiped. After a certain test is completed in step (8), the stains in the unconfined compressive strength module 7 are wiped.

Claims

1. A device for determining the physical and mechanical properties of self-compacting solidified soil, characterized in that: It includes a mixing module (1), a slump measurement module (2), a sample preparation module (3), a setting time measurement module (4), a curing module (5), a demolding module (6), and an unconfined compressive strength measurement module (7); The stirring module (1) includes a stirring box (17) with a discharge pipe (13) and a feed inlet (12). The stirring box (17) has a stirring assembly (11) above it, the discharge pipe (13) has a valve (14), and the bottom of the stirring box (17) is provided with a telescopic stirring rod (15). The slump measurement module (2) includes a slump bucket (21), a pulley (23), a vertical slide rail (24), and a slump measurement unit (27). The slump bucket (21) has a first groove (212) on both sides, and the pulley (23) has a second groove (231) on its side. A bracket (26) is inserted into the first groove (212) and the second groove (231). The pulley (23) moves along the vertical slide rail (24), and a lifting device (22) is connected to the bottom of the pulley (23). The slump measuring unit (27) includes a measuring plate (271) with a level bubble (28) and a central hole and groove. The measuring plate (271) has a support (273) below it. The measuring plate (271) has an upper circumference plate (274) and a lower folding plate (275) at its end. A leveling component (25) is installed on the lower folding plate (275). A soil sample control tube (272) is screwed to the bottom of the slump bucket (21). One end of the soil sample control tube (272) is screwed into the central hole. The sample preparation module (3) includes a pouring device (31) and a vibrating fork (34); the pouring device (31) includes a funnel (311) with a diverter pipe (312); one end of the diverter pipe (312) leads to the setting time measuring module (4), and the other end of the diverter pipe (312) is connected to a storage bottle (315); a servo motor (314) is connected above the storage bottle (315), and a pouring pipe (316) is connected below it; a mold (35) is connected below the pouring pipe (316); the mold (35) has shrink clamps (33) on both sides and a conveyor belt (32) at the bottom of the mold (35); The demolding module (6) includes telescopic rods (61) located at the bottom and on both sides. The ends of the telescopic rods (61) on both sides are provided with clamps (62) that hold the mold (35). The telescopic rods (61) at the bottom extend into the mold. The stirring module (1) is connected to the slump measuring module (2) through the discharge pipe (13), the sample preparation module (3) is connected to the slump measuring module (2) through the pouring device (31), and the setting time measuring module (4) is connected to the sample preparation module (3) through the diversion pipe (312). The unconfined compressive strength measuring module (7) includes a load sensor (71), a displacement sensor (72), a screw lifting device (73), and a data acquisition instrument (74). The load sensor (71) and the displacement sensor (72) are connected to the data acquisition instrument (74), and the displacement sensor (72) is distributed on the screw lifting device (73).

2. The device for determining the physical and mechanical properties of self-compacting solidified soil according to claim 1, characterized in that: The stirring assembly (11) includes a first servo motor (111), a telescopic rod (112), and a rotating blade (113), wherein the rotating blade (113) is sleeved on the telescopic rod (112).

3. The device for determining the physical and mechanical properties of self-compacting solidified soil according to claim 1, characterized in that: The leveling assembly (25) includes a support and a bolt (251) passing through the lower folding plate (275), on which a leveling nut (252) is screwed.

4. The device for determining the physical and mechanical properties of self-compacting solidified soil according to claim 1, characterized in that: The maintenance module (5) includes a water storage tank (57), a humidifier (51), a tray (52) for placing molds, a temperature sensor (53) and a humidity sensor (54). Above the water storage tank (57) are a filter screen (56) and a heating tube (58).

5. The device for determining the physical and mechanical properties of self-compacting solidified soil according to claim 4, characterized in that: The humidifier (51) includes a liquid storage bottle (511), a humidification tube (512), and a nozzle (513), wherein the humidification tube (512) controls the closing of the nozzle (513).

6. The device for determining the physical and mechanical properties of self-compacting solidified soil according to claim 1, characterized in that: A gasket (63) that extends into the mold (35) is installed on the telescopic rod (61) at the bottom.

7. The device for determining the physical and mechanical properties of self-compacting solidified soil according to claim 6, characterized in that: The port of the telescopic rod (61) is provided with a groove (64), and the clamp (62) and the gasket (63) are provided with protrusions that fit into the groove.

8. The device for determining the physical and mechanical properties of self-compacting solidified soil according to claim 1, characterized in that: The slump bucket (21) has connecting blocks on both sides, and the connecting blocks have a first groove (212) on their sides.

9. A method for determining the physical and mechanical properties of self-compacting solidified soil, characterized in that: The testing is performed using the self-compacting solidified soil physical and mechanical property testing device as described in claim 2, and the testing method includes the following steps: (1) After weighing the soil sample, water and curing agent, pour them into the mixing tank (17) through the feed inlet (12), control the telescopic rod (112) and rotating blade (113) of the mixing component (11) to move up and down, and rotate and mix until a soil sample that has formed self-compacting and solidified soil is formed. (2) Insert one end of the bracket (26) into the first groove on both sides of the slump bucket (21), and insert the other end of the bracket (26) into the second groove of the pulley (23). Adjust the lifting device (22) to drive the pulley (23) to move along the vertical slide rail (24) until the slump bucket (21) with the soil sample control tube (272) is inserted into the groove of the measuring plate (271). Adjust the leveling nut (252) to the horizontal position using the leveling bubble (28). (3) Open the valve (14) and the soil sample flows into the slump bucket (21) through the discharge pipe (13). Control the telescopic stirring rod (15) to insert and tamp into the slump bucket (21). After the soil sample fills the slump bucket (21), remove the discharge pipe (13) and the telescopic stirring rod (15). Control the lifting device (22) to move upward until the soil sample flows to a standstill. Read the spread data of the soil sample according to the measuring plate (271). (4) Adjust the shrink clamp (33) and clamp the mold (35), close the valve in the diversion pipe (312) leading to the setting time measurement module (4), unscrew the soil sample control tube (272), and the soil sample flows into the storage bottle (315) through the funnel (311), and then into the mold (35) through the pouring pipe (316). Move the vibration fork (34) to vibrate on both sides of the mold (35). After the mold (35) is poured, rotate the storage bottle (315) and move the conveyor belt (32) through the servo motor (314) to pour the next set of molds (35). (5) Open the valve to the setting time measuring module (4), and the remaining soil sample in the slump bucket flows into the setting time measuring module. Start timing and record the initial setting and final setting times of the soil sample. (6) Move the mold (35) after pouring the soil sample to the tray (52) of the curing module (5) and set the temperature and humidity; (7) After the soil sample is cured, take out the mold (35) and place it on the pad (63) of the demolding module (6). Install the clamp (62) on the telescopic rods on both sides and clamp the mold. Install the pad (63) on the telescopic rod at the bottom. Adjust the telescopic rod at the bottom to lift it up. Push the soil sample out of the mold (35) and place it in the curing module (5). (8) After curing to the specified age, the soil sample is taken out from the curing module (5) and placed on the screw lifting device (73) of the unconfined compressive strength testing module (7). It is raised to the top of the soil sample and stops after contacting the load sensor (71). After the readings of the load sensor (71) and the displacement sensor (72) are cleared to zero, the screw lifting device (73) is controlled to rise. The data acquisition instrument (74) records the strain data measured by the load sensor and the strength data measured by the displacement sensor during the test.

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