A device and method for preparing a rock column and filling body combined structure sample

Abstract

The present invention discloses a device and method for preparing a sample of a combined structure of a rock column and a filling body, which relates to the technical field of indoor rock mechanics tests, and comprises a retaining frame and at least one casting module, wherein each casting module is used to be fixed on the retaining frame, and the casting module comprises a forming carrier and at least one group of forming auxiliary parts; the forming carrier is used to accommodate the rock column sample, the filling body and the forming auxiliary parts; any group of forming auxiliary parts is placed in the forming carrier and cooperates with the forming carrier, so that the rock column sample and the filling body can form a combined structure in the forming carrier, and each group of forming auxiliary parts is used to form various combined structures respectively, which can meet the sample preparation requirements of the two-way combination of the rock column and the filling body and different types of tests.

Description

Technical Field

[0001] The invention relates to the technical field of indoor rock mechanics testing, and in particular to a device and method for preparing a rock column and filling body combined structure sample. Background Art

[0002] During the backfill mining process, after the backfill slurry is transported to the goaf, the pillars and the backfill will be cemented under the influence of underground temperature, humidity, stress and other environmental conditions to form a common load-bearing structure with a certain integrity. Understanding the evolution law of the bearing mechanical properties of the combined structure of the pillars and the backfill, the interaction mechanism between the backfill and the surrounding rock, etc. is crucial for the safety and stability research of the backfill mining area. It has become a common issue faced in the field of backfill mining, especially deep backfill mining.

[0003] Indoor tests are commonly used research methods in the field of rock mechanics. By conducting uniaxial, triaxial and shear tests on combined structure samples of rock pillars (pillar samples or surrounding rock samples) and backfill bodies, the bearing capacity and its evolution law of the combined structure of pillars and backfill bodies can be quantitatively studied from a mechanical perspective. At the same time, it helps to explore and reveal the interaction mechanism between backfill bodies and surrounding rocks. Among them, the reasonable preparation of combined structure samples of rock pillars and backfill bodies that meet the test specifications and standards is the premise and key to conducting indoor tests.

[0004] However, in the prior art, the preparation of rock column and filling body combined structure samples mainly has the following problems:

[0005] Different types of tests (such as uniaxial, conventional triaxial, true triaxial, shear, multi-field coupling, etc.) require different specimen styles. Traditional specimen preparation devices are generally designed and manufactured to prepare a specific type of specimen to meet the corresponding type of test requirements. They have single functions and poor compatibility. It is difficult to meet the specimen preparation requirements of the two-way combination of rock pillars and filling bodies and different types of tests through a set of specimen preparation devices. Summary of the invention

[0006] The purpose of the present invention is to provide a device and method for preparing a sample of a combined structure of a rock column and a filling body, so as to solve the problems existing in the above-mentioned prior art and meet the sample preparation requirements of a two-way combination of a rock column and a filling body and different types of tests.

[0007] To achieve the above object, the present invention provides the following solutions:

[0008] The present invention provides a device for preparing a sample of a combined structure of a rock column and a filling body, comprising a retaining frame and at least one casting module, each of the casting modules being used to be fixed on the retaining frame, and the casting module comprising a molding carrier and at least one group of molding auxiliary parts; the molding carrier being used to accommodate a rock column sample, a filling body and the molding auxiliary parts; any group of the molding auxiliary parts being placed in the molding carrier and cooperating with the molding carrier, so that the rock column sample and the filling body can form a combined structure in the molding carrier, and each group of the molding auxiliary parts is respectively used to form various combined structures.

[0009] Preferably, the retaining frame includes a base, a pressure plate and a connecting rod, one end of the connecting rod is used to be fixedly connected to the base, and the other end of the connecting rod is used to be fixedly connected to the pressure plate. The first end of each of the forming carriers is used to be fixed on the base, and the second end of each of the forming carriers is used to extend in a direction close to the pressure plate, and each of the second ends is open, and the rock column sample can extend into the forming carrier from the second end, and the pressure plate is used to press the rock column sample in the forming carrier.

[0010] Preferably, at least one first groove is formed on the surface of the base close to the pressing plate, and the number of the first grooves is equal to the number of the molding carriers, and the first end of each molding carrier is used to extend into each groove.

[0011] Preferably, at least one pressing head is detachably fixed on the surface of the pressing plate close to the base, and the number of the pressing heads is equal to the number of the forming carriers, and each pressing head is used to press each rock column sample in each forming carrier.

[0012] Preferably, the molding carrier includes a bottom plate and four side plates, the bottom plate is used to be fixed on the base, one end of each side plate is used to be fixed on the bottom plate, the other end of each side plate is used to extend toward the direction close to the pressure plate, and any two adjacent side plates are fixedly connected to form an annular cylinder.

[0013] Preferably, the cross-sectional shape of the annular cylinder is a square ring, and the number of the forming auxiliary parts is two groups; one group of the forming auxiliary parts includes a solid rectangular pad, which is used to be placed in the annular cylinder and the side wall of the solid rectangular pad can fit with the inner wall of the annular cylinder, and the height of the solid rectangular pad is less than the height of the annular cylinder; the other group of the forming auxiliary parts includes a hollow rectangular pad, which is used to be placed in the annular cylinder and the side wall of the hollow rectangular pad can fit with the inner wall of the annular cylinder, the height of the hollow rectangular pad is not less than the height of the annular cylinder, and the cross-sectional shape of the through hole on the hollow rectangular pad is circular.

[0014] Preferably, the bottom plate and each of the side plates are made of transparent material, and the bottom plate and each of the side plates have positioning scale lines, and a positioning line groove is provided on the bottom plate.

[0015] Preferably, the retaining frame also includes an adjusting spring and an adjusting nut, a through hole is opened on the pressure plate, and the end of the connecting rod away from the base has an external thread and can pass through the through hole; the adjusting spring is sleeved on the connecting rod, and one end surface of the adjusting spring is used to contact the base, and the other end surface of the adjusting spring is used to contact the pressure plate; the adjusting nut is used to be threadedly connected to the end of the connecting rod away from the base; the pressure plate can keep the rock column sample pressed in the forming carrier under the elastic force of the adjusting spring and the locking action of the adjusting nut.

[0016] Preferably, it also includes a monitoring component, which is used to monitor the state change of the combined structure forming process.

[0017] The present invention also provides a method for preparing a rock column and filling body combined structure sample, comprising the following steps:

[0018] Step 1: Place the base of the retainer on a flat ground, install the connecting rod, the adjusting spring and the pressing plate in sequence, and preliminarily fix the pressing plate by adjusting the nut;

[0019] Step 2: Assemble the bottom plate and four side plates of the molding carrier in the casting module, and place them in the first groove opened on the base after the assembly is completed;

[0020] Step 3: According to the type of the rock column and filling body combined structure sample to be prepared, determine whether the pressure head needs to be installed or replaced, and determine whether the forming auxiliary parts need to be installed. If the forming auxiliary parts need to be installed, then select the forming auxiliary parts to be installed;

[0021] Step 4: Place the rock column sample into the forming carrier, and adjust the rock column sample to the desired position according to the positioning grooves opened on the bottom plate and the positioning scale lines on the bottom plate. If it is determined according to step 3 that the pressure head needs to be installed, turn the adjusting nut so that the lower end surface of the pressure head is closely attached to the upper end surface of the rock column sample and pressed and fixed;

[0022] Step 5: Install relevant sensors (such as temperature and humidity sensors, strain gauges, etc.), and pull the connecting wires of the sensors out through the second end of the molding carrier to connect to the corresponding data acquisition and storage system;

[0023] Step 6, slowly pouring the evenly stirred slurry of the filling body from the second end into the molding space formed by the molding carrier and the molding auxiliary member, and making the molding space vibrate slightly to ensure that the molding space is completely filled with the slurry;

[0024] Step 7, placing the entire set of devices formed in Steps 1 to 6 into a curing box under specified conditions for continuous curing, and continuously observing the physical and mechanical parameters, morphological changes, etc. of the entire curing process through data collected by cameras and sensors;

[0025] Step eight, after the curing is completed, the entire set of equipment formed by steps one to seven is disassembled, the formed rock column and filling body combined structure specimens are removed and the corresponding indoor mechanical tests are carried out.

[0026] Compared with the prior art, the present invention has achieved the following technical effects:

[0027] The present invention provides an apparatus and method for preparing a rock column and a filling body combined structure sample. By setting a molding carrier and a molding auxiliary part used in conjunction with the molding carrier, the rock column sample and the filling body can form a combined structure in the molding carrier. When the molding auxiliary part does not participate in the molding process of the combined structure, the molding carrier itself can be relied on to prepare a combined structure sample. When the molding auxiliary part participates in the molding process of the combined structure, different styles of combined structure samples can be prepared by correspondingly using different molding auxiliary parts according to different sample preparation requirements. The overall structure is simple, and the combination of the molding carrier and the molding auxiliary part is flexible and changeable. Therefore, the apparatus for preparing a rock column and a filling body combined structure sample provided by the present invention can meet the preparation requirements of the rock column and the filling body combined structure sample of the diversified indoor test standards of the two-way combination and different types of tests (uniaxial, conventional triaxial, true triaxial, shear, multi-field coupling, etc.). BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 A schematic diagram of the overall structure of the device for preparing a rock column and filling body combined structure sample provided by the present invention;

[0030] Figure 2 for Figure 1 A schematic diagram of the cross-sectional structure at AA of the device for preparing a rock column and filling body combined structure sample;

[0031] Figure 3 for Figure 1 A schematic diagram of the cross-sectional structure at BB of the device for preparing a rock column and filling body combined structure sample;

[0032] Figure 4 for Figure 1 A schematic diagram of the cross-sectional structure at CC of the device for preparing a rock column and filling body combined structure sample;

[0033] Figure 5 for Figure 1 A schematic diagram of the cross-sectional structure at DD of the device for preparing a rock column and filling body combined structure sample;

[0034] Figure 6 for Figure 1 A schematic diagram of the cross-sectional structure at EE of the device for preparing a rock column and filling body combined structure sample;

[0035] Figure 7 for Figure 1 A schematic diagram of the split structure of the forming carrier of the device for preparing the rock column and filling body combined structure sample;

[0036] Figure 8 for Figure 1 A schematic diagram of a data acquisition structure of a device for preparing a rock column and filling body combined structure sample;

[0037] Fig. 9 for Figure 1 A schematic diagram of the structure of the forming auxiliary parts of the device for preparing a rock column and filling body combined structure specimen;

[0038] Fig.10 for Figure 1 Some examples of rock column and filling body combined structure samples that can be prepared by the device for preparing rock column and filling body combined structure samples.

[0039] In the figure: 1-pressing plate, 2-base, 3-connecting rod, 4-first groove, 5-pressing head, 6-bottom plate, 7-side plate, 8-solid rectangular spacer, 9-1 / 4 rounded spacer, 10-positioning scale line, 11-positioning wire groove, 12-adjusting spring, 13-adjusting nut, 14-camera, 15-sensor, 16-side plate slot, 17-rock column, 18-filling body. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] The purpose of the present invention is to provide a device and method for preparing a sample of a combined structure of a rock column and a filling body, so as to solve the problems existing in the above-mentioned prior art and meet the sample preparation requirements of a two-way combination of a rock column and a filling body and different types of tests.

[0042] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0043] At present, the research on the combined structure specimens of rock pillar and filling body includes the following:

[0044] (1) A mold and method for making a conventional test specimen of a composite rock mass of a filling body and surrounding rock, wherein a template is installed on the base, the template is composed of two semicircular structures, the lugs are connected to the reaction frame by fixing bolts, the reaction frame is placed above the template, the reaction frame is equipped with fixed top screws, and the upper pressure plate is composed of multiple split structures. According to the type of composite rock mass, the upper pressure plate applied to fix the upper plane of the surrounding rock and the number of matching fixed top screws are determined, the filling slurry is made and poured into the circular cavity filled with the surrounding rock, the unused upper pressure plate and fixed top screws in the split structure are applied to seal the composite rock mass specimen, the composite rock mass specimen is placed in a curing room for 24 hours to be demolded, the filling body is cured after demolding, and the cured specimen is polished into a standard specimen to avoid damage to the specimen caused by traditional on-site drilling and cutting sampling, thereby reducing the production cost.

[0045] (2) A plane biaxial loading test method simulating the interaction between the backfill and the pillar in two-step mining. The X-axis of the bidirectional loading system can simulate the surrounding rock squeezing the backfill, and the Y-axis can simulate the actual situation of the roof squeezing the pillar and the backfill. First, the pillar specimen is made, and then the backfill specimen is cast on both sides to make it an integral support unit. Strain and stress sensitive elements are installed inside and on the surface of the pillar specimen and the backfill, respectively, to test the stress and strain changes during the interaction between the backfill and the pillar. The plane biaxial loading method is adopted, and the axial pressure loading and confining pressure are controlled on a horizontal platform. The experiment is simple and easy.

[0046] (3) A method for testing the mechanical action mechanism of a filling body-rock column system, comprising the following steps: processing and preparing a rock column specimen and a self-made elastic module, and pasting, waterproofing and moisture-proofing the resistance strain gauge, pasting and waterproofing the rock column, and placing the strain gauge in the middle of a square side limit steel plate mold, burying the prepared filling slurry with a matching resistance strain gauge module into the filling body, and after the filling slurry fills the steel plate mold, scraping the surface, leading the wire connected to the strain gauge and marking it, and taking out the filling body after curing for a certain age, connecting the embedded strain gauge connecting wire to the strain gauge outside the device according to the test requirements, and then carrying out a loading test as required to analyze and study the deformation and failure law of the filling body, the rock column failure characteristics, and the compression time relationship characteristics during the loading process.

[0047] (4) A preparation device for a test specimen of a filling body with different layer combinations, comprising a base, a bottom mold, a top mold and a ring mold, wherein the base, the ring mold and the top mold are stacked in sequence to form a lower layer filling mold, and the bottom mold, the ring mold and the top mold are stacked in sequence to form an upper layer filling mold, wherein the upper layer filling mold is coaxially detachably connected with the lower layer filling mold. Ring molds of different heights are used to design a filling body combination specimen mold with different layer heights, which can ensure that the height of each layer meets the test design requirements, and the top mold and the bottom mold are used to connect the filling body specimens with different layers to ensure that the connection plane of each layer remains flat, thereby improving the reliability and accuracy of the test. Not only can different layer combination filling body specimens be prepared, but also filling body specimens of different heights under different test requirements can be prepared, which has the characteristics of multi-function and flexible sample preparation.

[0048] (5) Interaction mechanism between bulk filling and rock pillar under confinement conditions In order to study the interaction between bulk filling and surrounding rock in dry filling mining and analyze the influence of bulk filling on the mechanical properties of the pillar, a self-made test device for testing the axial compression performance of rock samples under the constraint of bulk filling was used to simulate the action process of bulk filling constraining the pillar, and compression tests of rock pillars under the constraint of bulk filling of different particle sizes were carried out. Based on the experimental analysis, a bearing model of the pillar during the interaction between bulk filling and the pillar was established.

[0049] Analysis of the current state of the art shows that scholars are generally more concerned with the mechanical properties of filling bodies and pillar-filling body composite structures. A lot of innovative research has been carried out on the preparation of filling body samples of different types (inclination angle, thickness combination), while the preparation of composite structure samples is relatively weak, which is specifically reflected in the following aspects:

[0050] (1) Traditional pillar-filling structure samples are mainly made by manual visual positioning and temporary fixation casting. The sample preparation accuracy is difficult to guarantee and the preparation efficiency is low.

[0051] (2) Traditional sample preparation equipment can often only prepare one type of pillar-backfill combination structure sample. Samples of different test types need to be reprocessed and prepared using different molds. This makes it difficult to meet the sample preparation requirements of the pillar-backfill bidirectional combination and diversified experiments (uniaxial, conventional triaxial, true triaxial, shear, multi-field coupling, etc.).

[0052] In view of the problems existing in the above-mentioned prior art and to meet the needs of multifunctional sample preparation, it is necessary to design and propose a multifunctional preparation device and method for a pillar-filling body combined structure sample.

[0053] Embodiment 1

[0054] like Figure 1-9 As shown, this embodiment provides a device for preparing a sample of a combined structure of a rock column 17 and a filling body 18, comprising a retaining frame and at least one casting module, each casting module being used to be fixed on the retaining frame, and the casting module comprising a molding carrier and at least one group of molding auxiliary parts; the molding carrier is used to accommodate the rock column 17 sample, the filling body 18 and the molding auxiliary parts; any group of molding auxiliary parts is placed in the molding carrier and cooperates with the molding carrier to enable the rock column 17 sample and the filling body 18 to form a combined structure in the molding carrier, and each group of molding auxiliary parts is used to form various combined structures respectively.

[0055] The device provided in this embodiment for preparing a sample of a combined structure of a rock column 17 and a filling body 18, by providing a molding carrier and a molding auxiliary part used in conjunction with the molding carrier, enables the rock column 17 sample and the filling body 18 to form a combined structure in the molding carrier, wherein, when the molding auxiliary part does not participate in the molding process of the combined structure, the molding carrier itself can be relied upon to prepare a combined structure sample; when the molding auxiliary part participates in the molding process of the combined structure, different types of combined structure samples can be prepared by using different molding auxiliary parts according to different sample preparation requirements. The overall structure is simple, and the combination of the molding carrier and the molding auxiliary parts is flexible and varied. Therefore, the device provided in this embodiment for preparing a sample of a combined structure of a rock column 17 and a filling body 18 can meet the preparation requirements of a diversified indoor test standard sample of a combined structure of a rock column 17 and a filling body 18 for a two-way combination and different types of tests (uniaxial, conventional triaxial, true triaxial, shear, multi-field coupling, etc.).

[0056] Furthermore, the retaining frame includes a base 2, a pressure plate 1 and a connecting rod 3, one end of the connecting rod 3 is used to be fixedly connected to the base 2, and the other end of the connecting rod 3 is used to be fixedly connected to the pressure plate 1. The first end of each molding carrier is used to be fixedly arranged on the base 2, and the second end of each molding carrier is used to extend toward the direction close to the pressure plate 1, and each second end is open, and the rock column 17 sample can extend into the molding carrier from the second end, and the pressure plate 1 is used to press the rock column 17 sample in the molding carrier. With this arrangement, a stable environment for sample preparation can be created, and at the same time, the rock column 17 sample can be kept fixed.

[0057] Furthermore, at least one first groove 4 is provided on the surface of the base 2 close to the pressure plate 1, and the number of the first grooves 4 is equal to the number of the molding carriers. The first end of each molding carrier is used to extend into each groove to facilitate the positioning and installation of each molding carrier.

[0058] Furthermore, at least one pressing head 5 is detachably fixed on the surface of the pressing plate 1 close to the base 2, and the number of the pressing heads 5 is equal to the number of the forming carriers. Each pressing head 5 is used to press each rock column 17 sample in each forming carrier. Whether to use the pressing head 5 and the specific shape and size of the pressing head 5 used need to be determined according to the actual sample preparation requirements.

[0059] Furthermore, the molding carrier includes a bottom plate 6 and four side plates 7. The bottom plate 6 is used to be fixed on the base 2. One end of each side plate 7 is used to be fixed on the bottom plate 6. The other end of each side plate 7 is used to extend toward the direction close to the pressing plate 1. Any adjacent two side plates 7 are fixedly connected to form an annular cylinder. The structure is simple and easy to disassemble and assemble, which can save manufacturing and maintenance costs.

[0060] Furthermore, the cross-sectional shape of the annular cylinder is a square ring, and the number of forming auxiliary parts is two groups; one group of forming auxiliary parts includes a solid rectangular pad 8, which is used to be placed in the annular cylinder and the side wall of the solid rectangular pad 8 can fit with the inner wall of the annular cylinder, and the height of the solid rectangular pad 8 is less than the height of the annular cylinder; the other group of forming auxiliary parts includes a hollow rectangular pad, which is used to be placed in the annular cylinder and the side wall of the hollow rectangular pad can fit with the inner wall of the annular cylinder, the height of the hollow rectangular pad is not less than the height of the annular cylinder, and the cross-sectional shape of the through hole on the hollow rectangular pad is circular, wherein the hollow rectangular pad can be an integrated type, or it can be formed by combining and installing multiple separate parts, such as Fig.10 As shown, some examples of combined structural samples of rock pillars 17 and filling bodies 18 that can be produced by using the forming carrier and the forming auxiliary parts in combination are shown.

[0061] Furthermore, the bottom plate 6 and each side plate 7 are made of transparent material, and there are positioning scale lines 10 on the bottom plate 6 and each side plate 7, and a positioning line groove 11 is opened on the bottom plate 6. By controlling the accurate positioning of the rock column 17 sample during the preparation process, the good preparation accuracy of the combined structure sample can be ensured. Among them, it is more preferred that the bottom plate 6 and each side plate 7 are made of high-strength transparent acrylic plate, which can ensure the reliability of the sample preparation process and extend the service life of the bottom plate 6 and each side plate 7.

[0062] Furthermore, the retaining frame also includes an adjusting spring 12 and an adjusting nut 13. A through hole is opened on the pressure plate 1, and the end of the connecting rod 3 away from the base 2 has an external thread and can pass through the through hole; the adjusting spring 12 is sleeved on the connecting rod 3, and one end face of the adjusting spring 12 is used to contact the base 2, and the other end face of the adjusting spring 12 is used to contact the pressure plate 1; the adjusting nut 13 is used to be threadedly connected with the end of the connecting rod 3 away from the base 2; the pressure plate 1 can keep the rock column 17 sample pressed in the forming carrier under the elastic force of the adjusting spring 12 and the locking action of the adjusting nut 13. This arrangement can facilitate the adjustment of the upper and lower positions of the pressure plate 1. Specifically, when the pressure plate 1 needs to be adjusted upward, the adjusting nut 13 is loosened, and the pressure plate 1 can move upward under the elastic force of the adjusting spring 12. When the pressure plate 1 needs to be adjusted downward, the adjusting nut 13 is tightened and the elastic force of the spring is overcome. The operation is simple and saves time and effort.

[0063] Furthermore, the device provided in this embodiment for preparing a combined structure sample of a rock column 17 and a filling body 18 also includes a monitoring component, which is used to monitor the state changes of the combined structure forming process, and can monitor the positioning of the rock column 17 sample and the entire process of pouring the filling slurry to form the combined structure, and meet the needs of continuous observation and analysis of the combined structure sample during the maintenance period.

[0064] Embodiment 2

[0065] This embodiment provides a method for preparing a sample of a structure of a rock column 17 and a filling body 18, comprising the following steps:

[0066] Step 1: Place the base 2 of the retainer on a flat ground, install the connecting rod 3, the adjusting spring 12 and the pressing plate 1 in sequence, and preliminarily fix the pressing plate 1 by adjusting the nut 13;

[0067] Step 2: Assemble the bottom plate 6 and four side plates 7 of the molding carrier in the casting module, and place them in the first groove 4 opened on the base 2 after the assembly is completed;

[0068] Step 3: According to the type of the combined structure sample of the rock column 17 and the filling body 18 to be prepared, determine whether the pressure head 5 needs to be installed or replaced, and determine whether a forming auxiliary part needs to be installed. If a forming auxiliary part needs to be installed, then select the forming auxiliary part to be installed;

[0069] Step 4: Place the rock column 17 sample into the forming carrier, and adjust the rock column 17 sample to the desired position according to the positioning groove 11 opened on the bottom plate 6 and the positioning scale line 10 on the bottom plate 6. If it is determined according to step 3 that the pressure head 5 needs to be installed, turn the adjusting nut 13 so that the lower end surface of the pressure head 5 is closely attached to the upper end surface of the rock column 17 sample and pressed and fixed;

[0070] Step 5: Install relevant sensors 15 (such as temperature and humidity sensors 15, strain gauges, etc.), and pull the connecting wires of the sensors 15 out through the second end of the molding carrier and connect them to the corresponding data acquisition and storage system;

[0071] Step 6, slowly pouring the evenly stirred slurry of the filling body 18 from the second end into the molding space formed by the molding carrier and the molding auxiliary member, and making the molding space vibrate slightly to ensure that the molding space is completely filled with the slurry;

[0072] Step 7, placing the entire set of devices formed in steps 1 to 6 into a curing box under specified conditions for continuous curing, and continuously observing the physical and mechanical parameters, morphological changes, etc. of the entire curing process through the data collected by the camera 14 and the sensor 15;

[0073] Step eight, after the curing is completed, the entire set of equipment formed in steps one to seven is disassembled, the combined structure sample of the formed rock column 17 and the filling body 18 is removed and the corresponding indoor mechanical test is carried out.

[0074] The method for preparing a combined structure sample of a rock column 17 and a filling body 18 provided in the present embodiment, by providing a molding carrier and a molding auxiliary part used in conjunction with the molding carrier, enables the rock column 17 sample and the filling body 18 to form a combined structure in the molding carrier, wherein, when the molding auxiliary part does not participate in the molding process of the combined structure, the preparation of a combined structure sample can be achieved by relying on the molding carrier itself; when the molding auxiliary part participates in the molding process of the combined structure, different styles of combined structure samples can be prepared by using different molding auxiliary parts according to different sample preparation requirements. The overall structure is simple, and the combination of the molding carrier and the molding auxiliary parts is flexible and varied. Therefore, the method for preparing a combined structure sample of a rock column 17 and a filling body 18 provided in the present embodiment can meet the preparation requirements of the diversified indoor test standard rock column 17 and a filling body 18 combined structure samples of the two-way combination of the rock column 17 and the filling body 18 and different types of tests (uniaxial, conventional triaxial, true triaxial, shear, multi-field coupling, etc.).

[0075] Embodiment 3

[0076] like Figure 1-10As shown, in this embodiment, the base 2, the pressure plate 1 and the connecting rod 3 are all made of stainless steel, the nominal diameter of the connecting rod 3 is M16, the length of the connecting rod 3 is not less than 230 mm, and the connecting rod 3 is sleeved with an adjustment spring 12 with a wire diameter of 2 mm, an outer diameter of 28 mm, and an expanded length of 300 mm to ensure that the pressure plate 1 has sufficient vertical adjustment space. One end of the connecting rod 3 is fastened to the rigid base 2 with a fixing screw. The rigid base 2 is 640 mm long, 120 mm wide, and 20 mm high. Three first grooves 4 are opened on the base 2, and adjacent The center spacing of the first grooves 4 is 170 mm, the length of each first groove 4 is 110.4 mm, the depth is 5 mm, and it is ensured that the bottom plate 6 can be just placed in the first groove 4, the length of the pressing plate 1 is 640 mm, the width is 50 mm, and the height is 15 mm, and a threaded hole with a nominal diameter of M8 is provided on the pressing plate 1 for connecting the pressure head 5. It should be noted that the connection between the pressure head 5 and the pressing plate 1 can be that the pressure head 5 is directly threadedly connected to the pressing plate 1, or that the pressure head 5 is fixed to the pressing plate 1 by connecting bolts, wherein the connecting bolts are fixedly connected to the pressure head 5 and the pressing plate 1 respectively; The bottom plate 6 is fastened in the first groove 4 on the base 2 by two fixing screws with a nominal diameter of M6. The bottom plate 6 and each side plate 7 are made of a high-strength transparent acrylic plate. The bottom plate 6 is provided with a side plate slot 16 for installing each side plate 7. Each adjacent side plate 7 is fixed by a fixing screw with a nominal diameter of M6. The bottom plate 6 is 110 mm long, 70 mm wide, and 15 mm high. The number of the side plate slots 16 is 4, and the length of the side plate slots 16 is 30.4 mm, the width is 5.2 mm, and the depth is 15 mm. The bottom plate 6 is also provided with a length of 25 mm and a width of 25 mm. A rectangular positioning groove 11 and a circular positioning groove 11 with a radius of 25 mm (the groove depth is 0.5 mm); a group of forming auxiliary parts include hollow rectangular pads, specifically four transparent 1 / 4 fillet pads 9 with a height of 50 mm or 100 mm, and a transparent solid rectangular pad 8 with a length of 50 mm, a width of 50 mm, and a height of 50 mm, and all are made of high-strength transparent acrylic material, mainly used to adjust the type of sample prepared by the device, wherein preferably, the transparent solid rectangular pad 8 has the same positioning scale lines 10 and positioning grooves 11 as those on the transparent acrylic bottom plate 6. Since the bottom plate 6 and each side plate 7 of the device are made of high-strength transparent acrylic plates, and space is left on the upper part of the forming carrier, it is convenient to continuously observe the entire forming process of the combined structure sample of the rock column 17 and the filling body 18 by means of photography, and the continuous change process of the combined structure sample during the curing period can be observed in depth and transparently by arranging temperature and humidity sensors 15, strain sensors 15, etc.

[0077] After assembling the above parts, determine whether the pressure head 5 needs to be installed or replaced according to the type of rock column 17 and backfill body 18 combined structure sample to be prepared, and determine whether the molding auxiliary parts need to be installed. If the molding auxiliary parts need to be installed, then select the molding auxiliary parts to be installed. For example, when it is necessary to prepare a rock column 17 and backfill body 18 combined structure sample with a cylindrical horizontal contact surface of 50 mm in diameter and 100 mm in height, at this time, since the diameter of the rock column 17 sample is 50 mm, the height is 50 mm and it is installed in the center of the lower part of the casting module, it is not necessary to install the pressure head 5. At this time, it is only necessary to install the four transparent 1 / 4 fillet pads 9 with a height of 100 mm in the molding auxiliary parts to the four corners of the molding carrier; when it is necessary to prepare a circumferential wrapping type with a length of 50 mm, a width of 50 mm and a height of 100 mm, When the square column rock column 17 and the filling body 18 are combined into a structural sample, it is first necessary to select a prism with a lower end face length of 25 mm and a width of 25 mm as the pressure head 5 and fix it to the pressure plate 1, and then place the rock column 17 sample with a length of 25 mm, a width of 25 mm and a height of 100 mm at the center position in the forming carrier, and carefully adjust the position of the rock column 17 sample according to the positioning groove 11 and the positioning scale line 10 on the bottom plate 6. After the position is confirmed to be correct, the adjusting nut 13 can be turned to tightly fit the lower end face of the pressure head 5 with the upper end face of the rock column 17 sample and press it to fix it. Then, according to the research needs, the corresponding sensors 15 (such as temperature and humidity sensors 15, strain gauges, etc.) are installed, and the connecting wires of the sensors 15 are pulled out through the upper opening of the forming carrier to connect to the corresponding data acquisition and storage system, and then the evenly stirred filling slurry is slowly poured into the forming carrier; according to the research needs, the whole set of equipment is placed in a curing box with set conditions for continuous curing, and the physical and mechanical parameters, morphological changes, etc. of the whole curing process are continuously observed through the data collected by the camera 14 and the sensor 15; after the curing is completed, the mold can be removed and the combined structure specimen of the formed rock column 17 and the filling body 18 can be removed and its corresponding indoor mechanical test can be carried out.

[0078] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A device for preparing a rock column and filling body combined structure sample, characterized in that: It comprises a retaining frame and at least one casting module, each of the casting modules is used to be fixed on the retaining frame, and the casting module comprises a forming carrier and at least one group of forming auxiliary parts; the forming carrier is used to accommodate a rock column sample, a filling body and the forming auxiliary parts; any group of the forming auxiliary parts is placed in the forming carrier and cooperates with the forming carrier to enable the rock column sample and the filling body to form a combined structure in the forming carrier, and each group of the forming auxiliary parts is used to form various combined structures respectively; The forming carrier comprises a bottom plate and four side plates, and any two adjacent side plates are fixedly connected to form an annular cylinder; The cross-sectional shape of the annular cylinder is a square ring, and the number of the forming auxiliary parts is two groups; one group of the forming auxiliary parts includes a solid rectangular pad, which is used to be placed in the annular cylinder and the side wall of the solid rectangular pad can fit with the inner wall of the annular cylinder, and the height of the solid rectangular pad is less than the height of the annular cylinder; the other group of the forming auxiliary parts includes a hollow rectangular pad, which is used to be placed in the annular cylinder and the side wall of the hollow rectangular pad can fit with the inner wall of the annular cylinder, the height of the hollow rectangular pad is not less than the height of the annular cylinder, and the cross-sectional shape of the through hole on the hollow rectangular pad is circular.

2. The device for preparing a rock column and filling body combined structure sample according to claim 1, characterized in that: The retaining frame includes a base, a pressure plate and a connecting rod, one end of the connecting rod is used to be fixedly connected to the base, and the other end of the connecting rod is used to be fixedly connected to the pressure plate. The first end of each of the forming carriers is used to be fixed on the base, and the second end of each of the forming carriers is used to extend in a direction close to the pressure plate, and each of the second ends is open. The rock column sample can extend into the forming carrier from the second end, and the pressure plate is used to press the rock column sample in the forming carrier.

3. The device for preparing a rock column and filling body combined structure sample according to claim 2, characterized in that: At least one first groove is formed on the surface of the base close to the pressing plate, and the number of the first grooves is equal to the number of the molding carriers. The first end of each molding carrier is used to extend into each groove.

4. The device for preparing a rock column and filling body combined structure sample according to claim 2, characterized in that: At least one pressing head is detachably fixed on the surface of the pressing plate close to the base, and the number of the pressing heads is equal to the number of the forming carriers. Each pressing head is used to press each rock column sample in each forming carrier.

5. The device for preparing a rock column and filling body combined structure sample according to claim 2, characterized in that: The bottom plate is used to be fixed on the base, one end of each of the side plates is used to be fixed on the bottom plate, and the other end of each of the side plates is used to extend toward the direction close to the pressure plate.

6. The device for preparing a rock column and filling body combined structure sample according to claim 1, characterized in that: The bottom plate and each of the side plates are made of transparent material, and the bottom plate and each of the side plates have positioning scale lines, and a positioning line groove is opened on the bottom plate.

7. The device for preparing a rock column and filling body combined structure sample according to claim 2, characterized in that: The retaining frame also includes an adjusting spring and an adjusting nut. A through hole is provided on the pressure plate. The end of the connecting rod away from the base has an external thread and can pass through the through hole. The adjusting spring is sleeved on the connecting rod, and one end surface of the adjusting spring is used to contact the base, and the other end surface of the adjusting spring is used to contact the pressure plate. The adjusting nut is used to be threadedly connected to the end of the connecting rod away from the base. The pressure plate can keep the rock column sample pressed in the forming carrier under the elastic force of the adjusting spring and the locking action of the adjusting nut.

8. The device for preparing a rock column and filling body combined structure sample according to claim 1, characterized in that: It also includes a monitoring component, which is used to monitor the state changes of the combined structure forming process.

9. A method for preparing a rock column and filling body combined structure sample, characterized in that: The following steps are involved: Step 1: Place the base of the retainer on a flat ground, install the connecting rod, the adjusting spring and the pressing plate in sequence, and preliminarily fix the pressing plate by adjusting the nut; Step 2: Assemble the bottom plate and four side plates of the molding carrier in the casting module, and place them in the first groove opened on the base after the assembly is completed; Step 3: According to the type of the rock column and filling body combined structure sample to be prepared, determine whether the pressure head needs to be installed or replaced, and determine whether the forming auxiliary parts need to be installed. If the forming auxiliary parts need to be installed, then select the forming auxiliary parts to be installed; Step 4: Place the rock column sample into the forming carrier, and adjust the rock column sample to the desired position according to the positioning grooves opened on the bottom plate and the positioning scale lines on the bottom plate. If it is determined according to step 3 that the pressure head needs to be installed, turn the adjusting nut so that the lower end surface of the pressure head is closely attached to the upper end surface of the rock column sample and pressed and fixed; Step 5: Install relevant sensors, including temperature and humidity sensors and strain gauges, and pull the connecting wires of the sensors out through the second end of the molding carrier to connect to the corresponding data acquisition and storage system; Step 6, slowly pouring the evenly stirred slurry of the filling body from the second end into the molding space formed by the molding carrier and the molding auxiliary member, and making the molding space vibrate slightly to ensure that the molding space is completely filled with the slurry; Step 7, placing the entire set of devices formed in Steps 1 to 6 into a curing box under specified conditions for continuous curing, and continuously observing the physical and mechanical parameters and morphological changes of the entire curing process through data collected by cameras and sensors; Step eight, after the curing is completed, the entire set of equipment formed by steps one to seven is disassembled, the formed rock column and filling body combined structure specimens are removed and the corresponding indoor mechanical tests are carried out.

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