Compaction forming device for compact fault broken soil body

Abstract

The utility model relates to a compaction forming device, in particular to a compaction forming device for compact fault broken soil. According to the device, a transparent PVC soft film is arranged on the inner side wall of a prefabricated hollow cylindrical barrel, a sample is put into the prefabricated hollow cylindrical barrel, and a long rod is manually rotated to drive a bearing to rotate, so that a stud in threaded connection with the bearing moves downwards; the compaction disc can be used for slowly compacting the sample in the prefabricated hollow cylindrical barrel to finally reach the preset height. The device is small in occupied area and convenient to carry and transport, and the prepared fault fracture zone remodeling sample does not generate elastic deformation after standing and can be completely taken out to ensure a certain weak cementation state; compared with related mechanical indexes given in data, physical and mechanical parameters such as dry density, cohesive force, internal friction angle, particle size distribution curve, permeability coefficient and the like basically accord with the various parameter indexes, and can be used for replacing an original fault structure.

Description

Technical Field

[0001] The utility model relates to a compaction and molding device, in particular to a compaction and molding device for dense fault-broken soil. Background Art

[0002] Dense fault-fragmented soils are formed naturally by long-term geological tectonic processes. They possess a dense structure, high degree of fragmentation, and small pore structures. However, obtaining undisturbed specimens on site and preparing them using traditional methods are difficult. To investigate the permeability and impermeability properties of fault-fragmented structures under in situ stress conditions, research is urgently needed to prepare reshaped samples of dense fault-fragmented soils.

[0003] As an alternative, the preparation of reshaped samples from fault fracture zones is currently the primary method for conducting small-scale laboratory experiments. There are two main approaches to preparing reshaped samples from fault fracture zones: one is a granular fill structure, where samples are prepared using geotechnical testing methods, using certain physical and mechanical parameters as sample preparation criteria (such as average dry density and continuous gradation curves); the other is a prefabricated fixed mold, where reshaped samples are prepared with physical and mechanical properties that are essentially identical to those of the fault-fragmented rock mass by adding binders such as cement and gypsum. The former often uses a single rock mass (such as sandstone, coal, or tuff) that has been artificially crushed and then filled. This method ignores the weakly cemented nature of fault-fragmented rock masses, such as metamorphic rocks formed by the re-cementation of partially broken rock mass after long-term geological processes, and clay minerals formed by the physical and chemical effects of water. While the latter can simulate the macroscopic properties of the rock mass to a certain extent, the artificially added binders make it difficult to accurately simulate the water-induced or seepage weakening of the fault-fragmented structure under natural conditions due to water-rock interaction. Therefore, remolded samples of dense fault-fragmented soil must not only maintain their original granularity, compacted state, and pore structure, but also exhibit a certain degree of weak cementation. Existing artificial compaction and filling techniques have limitations in this regard, and preparing small-scale specimens that meet standards under indoor conditions also faces numerous difficulties. Summary of the Invention

[0004] In order to solve the problems raised in the above-mentioned background technology, the utility model provides a compaction and molding device for dense fault-broken soil. The method is easy to operate and has low sample preparation cost. The reshaped sample can basically replace the original structure of the fault. The reshaped sample prepared by the utility model not only takes into account the crushing characteristics, but also takes into account the existence of weakly cemented materials.

[0005] The technical solution adopted in this utility model is:

[0006] A compaction and molding device for dense fault-broken soil, comprising a base, pillars, bolts, a sample holder, a prefabricated hollow cylindrical barrel, a compacting disc, a long rod, a bearing, a stud and a top plate, wherein the sample holder is fixed or disassembled on the base by bolts, the sample holder has a space for placing the prefabricated hollow cylindrical barrel, the height of the prefabricated hollow cylindrical barrel is greater than that of the sample holder, a transparent PVC soft film is provided on the inner side wall of the prefabricated hollow cylindrical barrel, vertical pillars are fixedly connected to the two sides of the base, the other ends of the two pillars are fixedly connected to the top plate, a bearing is fixedly connected inside the top plate, a threaded hole is vertically opened in the center of the bearing, the threaded hole is coaxial with the vertical center line of the prefabricated hollow cylindrical barrel, a stud is rotatably connected to the inner thread of the bearing, the long rod is located above the bearing and has a threaded hole opened in the center to be connected to the stud, and the stud is moved up and down in the bearing by rotating the long rod;

[0007] The bottom of the stud is connected with a compacting disc, and the compacting disc is located just above the prefabricated hollow cylindrical barrel.

[0008] Preferably, the center of the compacting disc is coaxial with the center of the prefabricated hollow cylindrical barrel, and the width of the annular gap between the compacting disc and the prefabricated hollow cylindrical barrel is equal to the thickness of the transparent PVC soft film.

[0009] Preferably, the outer diameter of the prefabricated hollow cylindrical barrel is equal to the inner diameter of the inner cylinder of the sample holder, and the prefabricated hollow cylindrical barrel can be disassembled in the sample holder.

[0010] Preferably, the prefabricated hollow cylindrical barrel is composed of two symmetrical semi-cylindrical barrels and is placed in a sample holder for fixation.

[0011] Preferably, a baffle is provided on the lower side of the stud above the compacting disc, the diameter of the baffle is larger than the outer diameter of the prefabricated hollow cylindrical barrel, and upper bolts and lower bolts are provided on the upper and lower sides of the baffle, and the height of the baffle is adjusted by the upper and lower bolts.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] 1. The utility model provides an operating environment for the device through a base, a sample holder and a prefabricated hollow cylindrical barrel, etc. The device occupies a small area and is easy to carry and transport.

[0014] 2. The base and prefabricated hollow cylindrical barrel in the utility model can be assembled and disassembled. If there are multiple bases and prefabricated hollow cylindrical barrels, when the sample is not subjected to the permeability characteristics and anti-permeability performance test under the in-situ stress state, multiple samples can be prefabricated, which is convenient for storage and improves the efficiency of the preliminary preparation work.

[0015] 3. The prefabricated hollow cylindrical barrel of the utility model is provided with transparent PVC soft film on the inner side wall, so that the sample will not be damaged when taken out of the prefabricated hollow cylinder, the weak cementation state can be ensured, and the subsequent in-situ stress state permeability and impermeability experiment can be carried out.

[0016] 4. The fault fracture zone remolded sample prepared by the utility model basically meets the respective parameter indexes compared with the related mechanical indexes given in the data according to the dry density, cohesion, internal friction angle, particle size distribution curve and permeability coefficient and other physical and mechanical parameters, can be used to replace the fault original structure, and the fault fracture zone remolded sample prepared by the device will not produce elastic deformation and can be directly taken out after standing to carry out subsequent experiments. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 It is a whole structure schematic view of the utility model device;

[0018] Figure 2 It is a top view of the prefabricated hollow cylindrical barrel of the utility model.

[0019] Among them: 1, base; 2, support; 3, bolt; 4, sample holder; 5, prefabricated hollow cylindrical barrel; 6, compaction disc; 7, baffle; 8, upper bolt; 9, lower bolt; 10, long rod; 11, bearing; 12, stud; 13, top plate. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the utility model.

[0021] For example, Figure 1 And Figure 2As shown, a compaction and molding device for dense fault-broken soil includes a base 1, a support 2, a bolt 3, a sample holder 4, a prefabricated hollow cylindrical barrel 5, a compacting disc 6, a long rod 10, a bearing 11, a stud 12 and a top plate 13. The sample holder 4 is fixed or disassembled on the base 1 by the bolt 3. There is a space for placing the prefabricated hollow cylindrical barrel 5 on the sample holder 4. The height of the prefabricated hollow cylindrical barrel 5 is greater than that of the sample holder 4. A transparent PVC soft film is provided on the inner wall of the prefabricated hollow cylindrical barrel 5. Vertical supports 2 are fixedly connected to both sides of the base 1. The other ends of the two supports 2 are fixedly connected to the top plate 13. The top plate 13 is fixedly connected with the bearing 11. The shaft A threaded hole is vertically opened in the center of the bearing 11, and the threaded hole is coaxial with the vertical center line of the prefabricated hollow cylindrical barrel 5. The inner thread of the bearing 11 is rotatably connected to a stud 12. The long rod 10 is located above the bearing 11 and has a threaded hole opened in the center to be connected to the stud 12. The long rod 10 is perpendicular to the stud 12, and the stud 12 can be moved up and down in the bearing 11 by rotating the long rod 10; the bottom of the stud 12 is connected to a compacting disc 6, and the compacting disc 6 is located directly above the prefabricated hollow cylindrical barrel 5. The center of the compacting disc 6 is coaxial with the center of the prefabricated hollow cylindrical barrel 5, and the width of the annular gap between the compacting disc 6 and the prefabricated hollow cylindrical barrel 5 is equal to the thickness of the transparent PVC soft film.

[0022] Specifically, the dense fault-broken soil compacted by the device is clay. After the compaction is completed, pulling open the prefabricated hollow cylindrical barrel 5 will pull the sample, making it difficult to shape the sample soil. In addition, during the compaction process, when the sample and the prefabricated hollow cylindrical barrel 5 are in contact and squeezed, a large lateral stress will be generated on the inner wall of the prefabricated hollow cylindrical barrel 5. The PVC soft film has high toughness and ductility due to its own material properties. During the soil compaction process, it will not be broken due to the large lateral stress. In addition, the dense fault-broken soil sample contains moisture, so the PVC soft film can be easily removed from the sample without damaging the sample.

[0023] Specifically, the outer diameter of the prefabricated hollow cylindrical barrel 5 is equal to the inner diameter of the inner cylinder of the sample holder 4 , and the prefabricated hollow cylindrical barrel 5 can be disassembled in the sample holder 4 .

[0024] Specifically, the prefabricated hollow cylindrical barrel 5 is composed of two symmetrical semi-cylindrical barrels and is placed in the sample holder 4 for fixation.

[0025] Specifically, a baffle 7 is provided on the lower side of the stud 12 and above the compacting disc. The diameter of the baffle 7 is larger than the outer diameter of the prefabricated hollow cylindrical barrel 5. Upper bolts 8 and lower bolts 9 are provided on the upper and lower sides of the baffle 7. The height of the baffle 7 is adjusted by the upper bolts 8 and the lower bolts 9.

[0026] The method for reshaping a sample by using the compaction and molding device to compact the fault-fragmented soil is as follows:

[0027] S1. Based on the particle size distribution curve of the fault fracture zone sample, compare and analyze the gradation distribution curve under different Talbot index conditions in the ideal Talbot continuous gradation formula to determine the value of the Talbot index;

[0028] S2. According to the Geotechnical Test Procedures, in the preparation of coarse-grained soil, the maximum particle size shall not exceed 1 / 5 of the sample diameter. The soil mass under various particle size conditions shall be prepared using the dry density and particle size distribution curve.

[0029] S3. Put a transparent PVC soft film on the inner wall of the prefabricated hollow cylindrical barrel 5, collect the loose particles of the broken structure of the fault on site, and pack them into numbered bags with different particle sizes through transportation, drying, screening and other steps. Typical compressive faults cannot be prepared into samples using normal filling and compaction methods due to their high density. Therefore, the coarse-grained soil filling method in the "Geotechnical Test Regulations" is used for initial artificial filling. The number of filling layers depends on the size of the prepared sample. If the cylindrical sample is "D50mm×H100mm", at least 3 layers are required. The sample is layered in the sample holder 4 and the prefabricated hollow cylindrical barrel 5 using a layered filling method;

[0030] S4. After filling the sample, fix the sample holder 4 to the base 1 by the bolt 3, and manually rotate the long rod 10 in one direction. At the same time, the stud 12 threadedly connected to the bearing 11 moves downward, driving the compacting disc 9 at the bottom of the stud 11 to slowly compact the sample in the prefabricated hollow cylindrical barrel 5, so that the particles inside the sample are continuously adjusted. When the compacting disc 9 is inserted into the prefabricated hollow cylindrical barrel 5, the operator needs to pull the transparent PVC soft film to prevent the film from being driven downward by the compacting disc 9. According to the predetermined height of the sample, the position of the baffle 7 is adjusted using the upper bolt 8 and the lower bolt 9. When the sample reaches the predetermined height after slow compaction, the compacting disc 6 at the bottom of the stud 12 is no longer pressed down in the prefabricated hollow cylindrical barrel 5 due to the restriction of the baffle 7;

[0031] S5. After the sample reaches the predetermined height, rotate the long rod 10 in the opposite direction so that the stud 12 drives the compaction disc 6 to move upward. Let it stand for 5 to 10 hours. Take out the sample and place it on the static table to air dry. Record the weight of the sample every day until the weight of the sample no longer changes and then proceed to the next step of the experiment.

[0032] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A compaction and molding device for dense fault-broken soil, characterized by: The invention comprises a base (1), a support (2), a bolt (3), a sample holder (4), a prefabricated hollow cylindrical barrel (5), a compacting disc (6), a long rod (10), a bearing (11), a stud (12) and a top plate (13), wherein the sample holder (4) is fixed or disassembled on the base (1) by means of the bolt (3), and the sample holder (4) has a space for placing the prefabricated hollow cylindrical barrel (5), the height of the prefabricated hollow cylindrical barrel (5) is greater than that of the sample holder (4), and a transparent PVC soft film is provided on the inner side wall of the prefabricated hollow cylindrical barrel (5), and the base (1) is fixed on both sides. A vertical support (2) is fixedly connected, and the other ends of the two support columns (2) are fixedly connected to a top plate (13), and a bearing (11) is fixedly connected inside the top plate (13), and a threaded hole is vertically opened in the center of the bearing (11), and the threaded hole is coaxial with the vertical center line of the prefabricated hollow cylindrical barrel (5), and a stud (12) is rotatably connected to the inner thread of the bearing (11), and the long rod (10) is located above the bearing (11) and has a threaded hole opened in the center to be connected to the stud (12), and the stud (12) is moved up and down in the bearing (11) by rotating the long rod (10); The bottom of the stud (12) is connected to a compacting disc (6), and the compacting disc (6) is located directly above the prefabricated hollow cylindrical barrel (5).

2. The compacting and forming device for dense fault-broken soil according to claim 1, characterized in that: The center of the compacting disc (6) is coaxial with the center of the prefabricated hollow cylindrical barrel (5), and the width of the annular gap between the compacting disc (6) and the prefabricated hollow cylindrical barrel (5) is equal to the thickness of the transparent PVC soft film.

3. The compacting and forming device for dense fault-broken soil according to claim 1, characterized in that: The outer diameter of the prefabricated hollow cylindrical barrel (5) is equal to the inner diameter of the inner cylinder of the sample holder (4), and the prefabricated hollow cylindrical barrel (5) can be disassembled in the sample holder (4).

4. The compacting and forming device for dense fault-broken soil according to claim 3, characterized in that: The prefabricated hollow cylindrical barrel (5) is composed of two symmetrical semi-cylindrical barrels and is placed in the sample holder (4) for fixation.

5. The compacting and forming device for dense fault-broken soil according to claim 1, characterized in that: A baffle (7) is provided on the lower side of the stud (12) and above the compacting disc. The diameter of the baffle (7) is larger than the outer diameter of the prefabricated hollow cylindrical barrel (5). Upper bolts (8) and lower bolts (9) are provided on the upper and lower sides of the baffle (7). The height of the baffle (7) is adjusted by the upper bolts (8) and the lower bolts (9).

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