Air pressure type soil sampling device for soil consolidation test

Abstract

The utility model discloses a kind of air pressure type mud crust soil consolidation test soil sampling device, it is related to soil sampling equipment technical field, including acrylic barrel, lifting screen support, top cover, base support and lifting controller.Acrylic barrel is transparent cylindrical container, is equipped with drain and annular clamping groove;Lifting screen support is composed of lifting rod and stainless steel net, is installed in barrel by clamping groove, and height can be adjusted;Top cover is equipped with air outlet, air inlet, and is sealingly connected with barrel body;Base support guarantees device stability;Lifting controller drives lifting rod synchronous extension and contraction.The device can realize mud crust soil uniform consolidation and nondestructive sampling, solve traditional sampling low efficiency, sample easy damage problem, simple structure, convenient operation, provide reliable tool for pile foundation engineering research.

Description

Technical Field

[0001] This utility model relates to the technical field of soil sampling equipment, specifically to a pneumatic soil consolidation test soil sampling device. Background Technology

[0002] In large-scale infrastructure construction, bored piles are a core foundation type, and their construction quality directly determines the safety of the project. During the pile formation process, a mud cake structure is formed on the pile hole wall by the interaction of the wall-protecting mud and the clay particles of the stratum. This mud cake layer is only a few millimeters thick, but it plays a decisive role in the bearing capacity of the pile foundation, the side friction resistance at the pile-soil interface, and its long-term stability and durability.

[0003] Obtaining representative mud cake samples and accurately measuring their physical and mechanical properties in the laboratory is a crucial step in pile foundation engineering research. However, existing technologies have significant drawbacks: mud cake has low strength and strong structure, making it easy to damage samples with traditional manual sampling; after the mud cake is consolidated in a cylindrical container, operators need to insert their bodies or tools into the container to operate, which is not only inefficient but also causes irreversible damage to the fragile mud cake structure, making it difficult to achieve uniform and non-destructive sampling across the entire depth range. Developing new, convenient, and non-destructive sampling devices has become an urgent need in engineering practice. Utility Model Content

[0004] This invention aims to solve the problems of low efficiency and easy sample damage in existing soil sampling devices for mud cake soil sampling, and provides a pneumatic soil consolidation test soil sampling device, the specific technical solution of which is as follows:

[0005] A pneumatic soil consolidation test soil sampling device includes an acrylic bucket, a lifting mesh support, a top cover, a base support, and a lifting controller. The components work together to achieve soil consolidation and non-destructive sampling.

[0006] Acrylic Bucket: A cylindrical container made of transparent acrylic material, facilitating observation of the internal soil condition. The upper end is open for easy placement of the bedding layer, soil, and installation components; the lower end is closed with a central drainage outlet to remove excess moisture during soil consolidation. Both the top and bottom of the bucket have annular acrylic plates with an outer diameter larger than the bucket body, which are joined to the bucket's ends using a heat-fusion process to enhance structural strength. Multiple bolt holes are evenly distributed at equal angles along the circumference of the annular acrylic plate at the top of the bucket for connection to the top cover. An annular groove is located on the inner upper part of the bucket; the radial width and axial height of the groove match the dimensions of the connecting part of the lifting mesh support, ensuring stable installation of the lifting mesh support.

[0007] The lifting mesh support bracket is installed inside the acrylic bucket via a slotted structure and consists of four lifting rods and a stainless steel mesh. The diameter of the stainless steel mesh is slightly smaller than the inner diameter of the acrylic bucket, allowing it to be stably placed inside and supporting the mud. The bottoms of the four lifting rods are fixed to the edges of the stainless steel mesh with bolts, ensuring a secure connection. The top is fixed to an acrylic ring, and the outer diameter of the acrylic ring precisely matches the inner diameter of the annular slot inside the acrylic bucket, thus securing the bracket. The lifting rod is a multi-stage nested telescopic structure consisting of an outer tube, a middle tube, and an inner tube. The lower end of the inner tube is equipped with a spring-loaded latch mechanism, which includes a return spring and an arc-shaped latch. When the inner tube aligns with the edge groove of the stainless steel mesh, the arc-shaped latch engages with the groove under the action of the return spring. Pressing the end of the latch releases the lock, allowing for quick connection and separation from the stainless steel mesh and improving the efficiency of device assembly and disassembly. Adjacent nested sleeves achieve telescopic movement through sliding fit, and a limiting structure is provided to prevent complete separation of the pipe sections. The height of the stainless steel mesh can be flexibly adjusted by extending and retracting the lifting rod, enabling the stable lifting and non-destructive removal of the consolidated mud sample.

[0008] The inner wall of the middle tube has two symmetrical rectangular slide rails along the axial direction, and the outer wall of the inner tube has protrusions that match the slide rails to ensure that the inner tube only expands and contracts along the axial direction and has no radial offset.

[0009] Furthermore, the telescopic control method of the lifting rod, when the lifting controller drives the lifting rod to extend or retract, achieves precise positioning through the following steps: 1) Rotating the control handle generates an initial tension through the linkage mechanism composed of the cross-shaped linkage frame and the rotatable connecting rod; 2) The first-stage locking knob between the outer tube and the middle tube is released first, and the middle tube extends smoothly along the inner wall of the outer tube, achieving initial extension; 3) When the middle tube extends to its limit position, the tension is transmitted to the connection between the middle tube and the inner tube, and the inner tube, constrained by the slide rail preset on the inner wall of the middle tube, achieves smooth linear extension; 4) The inner tube drives the stainless steel mesh... 5) When the control handle is rotated in the opposite direction, the cross-shaped linkage frame drives the rotatable connecting rod to generate a reverse thrust. This thrust first acts on the nested locking groove of the inner tube and the middle tube. When the inner tube retracts to the preset limit position of the middle tube, the protruding structure in the groove engages with the groove on the outer wall of the inner tube, realizing the initial locking of the middle tube and the inner tube. As the control handle continues to rotate in the opposite direction, the thrust is transmitted to the first-stage locking knob of the outer tube and the middle tube. The threaded structure in the knob automatically tightens under the action of the thrust, completing the locking of the outer tube and the middle tube, and finally realizing the synchronous retraction of each tube section and the outer tube remaining stationary throughout the entire process.

[0010] Top Cover: Fits the open top of the acrylic bucket, made of the same material and with the same outer diameter as the annular acrylic plate at the top of the bucket. Several through bolt holes are provided along the circumferential edge of the top cover, their number and location corresponding to the bolt holes on the annular acrylic plate at the top of the bucket. The top cover is securely connected to the acrylic bucket using bolts, nuts, and flat washers to ensure a tight seal. The top cover has through air outlets and inlets, each equipped with a valve assembly with a sealing structure for regulating internal air pressure during the soil consolidation stage.

[0011] Base support: Located below the acrylic bucket, it includes a support platform and support leg assemblies. The support platform is a rectangular flat plate structure with a central opening to facilitate drainage from the bottom drain of the acrylic bucket; the support leg assembly consists of four metal pillars, each vertically welded to the four corners of the support platform's bottom surface, ensuring the base support has sufficient load-bearing capacity and guaranteeing stable placement of the device.

[0012] Lifting Controller: This is a manually operated structure, adapted to the four lifting rods of the lifting mesh support. Its core consists of a control handle, a cross-shaped linkage frame, and rotatable connecting rods. The central axis of the control handle is welded to the center of the cross-shaped linkage frame to form a synchronous assembly. The cross-shaped linkage frame has a symmetrical structure, with each of its four ends connected to one of the four lifting rods via rotatable connecting rods. Both ends of the connecting rods are hinged, movably connected to pre-drilled holes at the ends of the linkage frame and to connecting lugs on the outer walls of the lifting rods, ensuring no jamming. During operation, rotating the control handle causes the cross-shaped linkage frame to rotate synchronously. The linkage mechanism converts this rotational motion into synchronous axial extension and retraction of the four lifting rods, preventing the support from tilting, ensuring the mud sample remains horizontal, and achieving stable, complete lifting and non-destructive sampling.

[0013] The beneficial effects of this utility model are as follows:

[0014] 1. By using an acrylic bucket as the main container, the transparent material makes it easy to observe the internal situation;

[0015] 2. The height of the lifting mesh support is adjustable. Its core function is to drive the consolidated mud and soil to rise steadily, so as to achieve non-destructive sampling.

[0016] 3. The top cover is tightly connected to the acrylic bucket, and the combination of air inlet and air outlet can provide an air pressure environment for the consolidation of mud and soil.

[0017] 4. The base support ensures the device is placed stably and does not affect drainage.

[0018] 5. The lifting controller can drive the four lifting rods to extend and retract synchronously, effectively preventing the lifting mesh support from tilting; it can accurately and steadily lift the consolidated mud and soil samples, making operation simple and significantly improving the integrity and efficiency of sampling.

[0019] The entire device has a reasonable structural design and is easy to operate. It can effectively achieve non-destructive sampling of mud and soil, improve sampling efficiency and quality, and has good practical value. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0022] Figure 2 This is a schematic diagram of the top cover structure;

[0023] Figure 3 This is a schematic diagram of the lifting mesh support structure;

[0024] Figure 4 This is a cross-sectional view of the lifting boom;

[0025] Figure 5 This is a schematic diagram of an acrylic barrel structure;

[0026] Figure 6 This is a schematic diagram of the base support structure.

[0027] The markings in the diagram are as follows: 1-Top cover, 1-1-Air outlet, 1-2-Air inlet, 2-Lifting mesh bracket, 2-1-Acrylic ring, 2-2-Connecting ear, 2-3-Lifting rod, 2-4-Stainless steel mesh, 3-Acrylic bucket, 3-1-Drain outlet, 4-Base bracket, 4-1-Bearing platform, 4-2-Support leg assembly, 5-Lifting controller, 5-1-Control handle, 5-2-Cross-shaped linkage frame, 5-3-Rotable connecting rod, 6-1-Outer tube, 6-2-Middle tube, 6-3-Inner tube, 6-4-First-stage locking knob. Detailed Implementation

[0028] The present invention will be further described below with reference to the accompanying drawings and embodiments. The embodiments are merely preferred options and are not intended to limit the scope of protection of the present invention.

[0029] Before using the pneumatic soil consolidation test sampling device, the sampling location for the soil must be accurately determined according to the project requirements. The selected location should be representative and reflect the true characteristics of the soil in the study area. At the same time, it is necessary to carefully check whether all components of the device are complete, check whether the acrylic barrel has cracks or damage, whether the lifting rod of the lifting mesh support extends and retracts smoothly, whether the stainless steel mesh is deformed or damaged, whether the air outlet and air inlet valves of the top cover can open and close normally, and whether the supporting platform of the base support is dented and whether the support legs are stable, etc., to ensure that all components are intact and the device can operate normally.

[0030] During device assembly, first clean the surface of the base support 4 and bearing platform 4-1 to ensure there are no protruding foreign objects, then place it stably on a solid, level ground. Next, place the acrylic bucket 3 vertically on the bearing platform 4-1 of the base support 4, and adjust the position of the acrylic bucket 3 so that the drain outlet 3-1 at the bottom of the bucket is completely aligned with the center opening of the bearing platform 4-1, ensuring that the water discharged from the drain outlet 3-1 can completely pass through the center opening to ensure smooth drainage. The axis of the acrylic bucket 3 should also be perpendicular to the ground. Afterward, lay a drainage and filtration layer (such as geotextile, 2-5mm gravel, standard sand, etc., with the thickness determined according to the test plan) inside the acrylic bucket 3. During the laying process, each layer must be compacted to ensure a flat surface and avoid local depressions or protrusions.

[0031] After the subbase is laid, the lifting mesh support 2 is installed. First, align the acrylic ring 2-1 of the lifting mesh support 2 with and insert it into the annular groove inside the acrylic barrel 3 to initially fix the position of the support. Then, by pressing the spring buckle mechanism at the lower end of the inner tube 6-3, confirm its engagement with the edge groove of the stainless steel mesh 2-4 to ensure a reliable and secure connection. Hinge the rotatable connecting rod 5-3 of the lifting controller 5 with the preset connecting lug 2-2 of the lifting rod one by one, and rotate the control handle 5-1 to generate initial tension through the connecting rod mechanism 5-2. Since the outer tube remains stationary, the tension is first applied to the connection between the outer tube 6-1 and the middle tube 6-2, causing the first-stage locking knob 6-4 between the outer tube 6-1 and the middle tube 6-2 to release first. The middle tube 6-2 then extends smoothly along the inner wall of the outer tube 6-1, achieving the initial extension of the lifting rod 2-3. After the middle tube 6-2 extends to its limit position, the tension is transferred to the connection between the middle tube 6-2 and the inner tube 6-3. The inner tube 6-3, with the help of the slide rail on the inner wall of the middle tube 6-2 constraining its movement direction, extends smoothly in a straight line until the inner tube 6-3 drives the stainless steel mesh 2-4 to smoothly adhere to the padding layer. Finally, the reverse fine-tuning control handle 5-1 automatically locks the nested locking groove between the middle tube 6-2 and the inner tube 6-3, and the first-stage locking knob 6-4 between the outer tube 6-1 and the middle tube 6-2, completing the height fixation of the lifting mesh support 2. Throughout the process, the outer tube remains stationary, ensuring the overall stability of the support without shaking.

[0032] Subsequently, a layer of geotextile is laid on the stainless steel mesh 2-4, and the mud slurry to be consolidated is placed on the stainless steel mesh 2-4 of the lifting mesh support 2. The top cover 1 is then installed and sealed. Compressed air is introduced through the air inlet 1-2 of the top cover to adjust the air pressure inside the device to 0.1-0.4MPa (the specific pressure is determined according to the moisture content of the mud slurry), and this air pressure is maintained for 3-6 hours to complete the consolidation. The thickness of the cushion layer is 20-30cm, consisting of 2 layers of geotextile, 10-15cm of 5-10mm gravel, and 10-15cm of standard sand. During the consolidation process, moisture is discharged through the cushion layer and drainage outlet.

[0033] After the mud and soil have solidified, open the air outlet valve 1-1 to release the air pressure in the device. Once the air pressure is consistent with the outside pressure, loosen the bolts and remove the top cover 1. Then, hinge the rotatable connecting rod 5-3 of the lifting controller 5 to the four lifting rod connecting lugs 2-2 of the lifting mesh support 2 one by one to complete the connection between the lifting controller 5 and the lifting mesh support 2. Next, rotate the control handle 5-1 of the lifting controller 5 to drive the cross-shaped linkage frame 5-2 to operate synchronously. Through the rotatable connecting rod 5-3, drive the four lifting rods 2-3 to extend and retract synchronously and smoothly, so that the stainless steel mesh 2-4 carrying the solidified mud and soil slowly rises from the acrylic bucket 3, thus obtaining a complete and undamaged mud and soil sample.

[0034] Through the above steps, efficient consolidation and complete sampling of mud-covered soil can be achieved, preserving its physical and mechanical properties and key chemical components in situ to the greatest extent, providing real and reliable test data for pile foundation engineering quality assessment.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A pneumatic soil consolidation test sampling device, characterized in that, Includes an acrylic bucket (3), a lifting mesh support (2), a top cover (1), a base support (4), and a lifting controller (5); The acrylic bucket (3) is a transparent cylindrical container with an open top and a closed bottom. The closed bottom structure has a drain outlet (3-1) in the center. The top and bottom of the acrylic bucket (3) are provided with annular acrylic plates with an outer diameter larger than the bucket body. Multiple bolt holes are opened along the circumference of the edge of the annular acrylic plate. The inner side of the upper part of the acrylic bucket (3) is provided with annular groove. The lifting mesh support (2) is installed inside the acrylic barrel (3) through an annular slot. It consists of 4 lifting rods (2-3) and stainless steel mesh (2-4). The bottom of the 4 lifting rods (2-3) is fixed to the edge of the stainless steel mesh (2-4) with bolts, and the top is fixed to the acrylic ring (2-1). The outer diameter of the acrylic ring (2-1) is adapted to the inner diameter of the annular slot. The lifting rod (2-3) is a multi-level nested telescopic structure composed of an outer tube (6-1), a middle tube (6-2), and an inner tube (6-3). The lower end of the inner tube (6-3) is provided with a spring buckle mechanism, and a limiting structure is provided between adjacent nested sleeves. The top cover (1) is adapted to be installed at the upper opening of the acrylic bucket (3). The top cover (1) has through bolt holes on its circumferential edge that correspond to the bolt holes of the upper annular acrylic plate. The top cover (1) is fastened to the acrylic bucket (3) by bolts, nuts and flat washers. The top cover (1) has an air outlet (1-1) and an air inlet (1-2) with a valve assembly with a sealing structure on its plate. The base support (4) includes a bearing platform (4-1) and a support leg assembly (4-2). The bearing platform (4-1) is a rectangular plate with a central opening. The support leg assembly (4-2) consists of four metal pillars, which are vertically welded to the four corners of the bottom surface of the bearing platform (4-1). The lifting controller (5) includes a control handle (5-1), a cross-shaped linkage frame (5-2), and a rotatable connecting rod (5-3). The central axis of the control handle (5-1) is welded and fixed to the center of the cross-shaped linkage frame (5-2). The four ends of the cross-shaped linkage frame (5-2) are respectively hinged to the four lifting rods (2-3) through the rotatable connecting rod (5-3). The two ends of the rotatable connecting rod (5-3) are respectively movably connected to the preset holes at the ends of the cross-shaped linkage frame (5-2) and the connecting lugs (2-2) on the outer wall of the lifting rods (2-3).

2. The pneumatic soil consolidation test sampling device according to claim 1, characterized in that, The annular acrylic plates at the top and bottom of the acrylic barrel (3) are joined to the barrel port by a hot-melt process.

3. The pneumatic soil consolidation test sampling device according to claim 1, characterized in that, The radial width and axial height of the annular groove on the upper inner side of the acrylic barrel (3) match the size of the acrylic ring (2-1) of the lifting mesh support (2).

4. The pneumatic soil consolidation test sampling device according to claim 1, characterized in that, The diameter of the stainless steel mesh (2-4) is smaller than the inner diameter of the acrylic barrel (3).

5. The pneumatic soil consolidation test sampling device according to claim 1, characterized in that, The lifting rod (2-3) has a first-stage locking knob (6-4) between the outer tube (6-1) and the middle tube (6-2), and a nested locking groove between the middle tube (6-2) and the inner tube (6-3).

6. The pneumatic soil consolidation test sampling device according to claim 1, characterized in that, The center opening of the support platform (4-1) of the base bracket (4) is aligned with the drain outlet (3-1) at the lower end of the acrylic bucket (3).

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