CN112903452A - Device and method for testing tensile strength of multiple rows of grouped columns in horizontal goaf under influence of disturbance - Google Patents
Device and method for testing tensile strength of multiple rows of grouped columns in horizontal goaf under influence of disturbance Download PDFInfo
- Publication number
- CN112903452A CN112903452A CN202110151070.7A CN202110151070A CN112903452A CN 112903452 A CN112903452 A CN 112903452A CN 202110151070 A CN202110151070 A CN 202110151070A CN 112903452 A CN112903452 A CN 112903452A
- Authority
- CN
- China
- Prior art keywords
- disturbance
- loading
- testing
- column
- test
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/08—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
- G01N3/10—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces generated by pneumatic or hydraulic pressure
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/02—Details
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0014—Type of force applied
- G01N2203/0016—Tensile or compressive
- G01N2203/0017—Tensile
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/003—Generation of the force
- G01N2203/0042—Pneumatic or hydraulic means
- G01N2203/0048—Hydraulic means
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/025—Geometry of the test
- G01N2203/0252—Monoaxial, i.e. the forces being applied along a single axis of the specimen
Abstract
The invention discloses a device and a method for testing the tensile strength of multiple rows of grouped columns in a horizontal goaf under the influence of disturbance. The device comprises a tester base, a rack, a lower loading jaw, an upper pressing plate, a workbench, a cross frame, a main loading rod, a main loading oil cylinder, a pressure sensor, a disturbance force sensor, a protection ring, a half ball seat, an upper pressing plate, a directional bearing, a disturbance oil cylinder and a disturbance rod; the base is provided with four protection rings, a rack is arranged in each protection ring, one end of each rack is connected with the base, the other end of each rack is connected with the cross frame, five rows of lower loading jaws which are positioned on the same central line are arranged on one workbench, and synchronous stretching of 1-25 test pieces can be realized. The invention can realize the synchronous loading of a plurality of coal, rock, filling bodies, concrete, coal-filling and rock-filling test pieces, can obtain the tensile capability of the horizontal goaf multi-row grouped column system under the condition of disturbance loading, and obtains the mutual influence relationship among the horizontal goaf grouped column individuals.
Description
Technical Field
The invention relates to a device and a method for testing the tensile strength of a plurality of rows of group columns in a horizontal goaf under the influence of disturbance, which are mainly suitable for a device and a method for synchronously loading a plurality of coal, rock, filling bodies, concrete, coal-filling samples and rock-filling samples, and belong to the technical field of mining rock mechanical tests.
Background
Due to the laggard mining method in the old mining period, a large number of left-over coal pillars are formed in a plurality of mines in China, and the method mainly comprises the following steps: the coal pillar group is formed by combining a cutter pillar type, a room pillar type, a strip type, a short-wall type, a roadway mining type, a warehouse type and a jump mining type. Similarly, pillar clusters are also formed in the goaf during metal mining to carry overburden loads and to ensure long term stability of the stope.
The filling mining can effectively control the overburden movement and the surface subsidence. In recent years, in order to solve the technical problems of insufficient sources of filling materials, high cost and the like, the method comprises the technical methods of partial filling, roadside filling, strip filling, pier column filling, local filling, short wall filling, strip filling, interval filling, pillar side filling, structural filling, functional filling, framework type filling and the like, and is applied and popularized in a plurality of mines. The filling mining technical method is inevitable to reserve filling columns (concrete columns) with different sizes/shapes in the goaf, and the filling columns are distributed in a group column mode and combined to form filling body group columns or concrete group columns.
The above coal pillar group, ore pillar group, packed pillar group, and concrete group are collectively referred to herein as "pillar group". The initial purpose of reserving stope group columns is to bear the load of an overlying strata and ensure the long-term stability of a goaf. The long-term stability of stope crowd columns is a scientific issue of concern. However, under the coupling action of overburden load, disturbance load, mine water erosion, sulfate corrosion, chloride corrosion, natural weathering and the like, the bearing capacity of the stope group column is gradually weakened, instability of a group column system can be caused, so that disasters such as overburden collapse, surface subsidence and the like are caused, and great potential safety hazards are brought to safe and efficient mining of coal resources.
The goaf leaving group column can be subjected to strong external disturbance action besides the static load of the overlying load, the disturbance action seriously threatens the personal safety and the engineering quality of engineering personnel, and the traditional testing machine cannot research the single-bearing load capacity of the leaving group column under the disturbance. However, the traditional testing machine can only load a single coal pillar, cannot carry out double-shaft loading on a plurality of groups of pillars, and cannot research the bearing capacity of a group of pillar systems for overlying loads after the pillars are filled beside the pillars.
The independent individuals of the stope group columns have mutual influence, and overlying strata load, disturbance load and the like are not borne by a single stope column body and are mainly borne together through a group column system. If one column body is locally destabilized and damaged, the overburden load and the disturbance load are transferred, so that the destabilization of adjacent group columns is damaged, and the chain-type instability of domino of the stope group columns is caused. Therefore, it is highly necessary to test the overall load bearing capacity of the stope group column system. At present, the overall bearing capacity of a group column of a field monitoring stope is difficult to realize, and the group column can only be tested by a small-size group column sample of a laboratory. The traditional testing machine can only load a single column sample, and can not load a group of column samples.
In summary, it is urgently needed to develop a testing device and method for the whole bearing capacity of the stope group column, so as to obtain the whole bearing capacity of the stope group column system, obtain the mutual influence relation between the group column individuals, lay a foundation for revealing the chain instability response characteristics and mechanism of the stope group column, and provide guidance for the development of the stope group column chain instability prevention and control technology. The invention provides a device and a method for testing the tensile strength of horizontal goaf multi-row grouped columns under the influence of disturbance, and aims to provide a focusing horizontal goaf multi-row grouped column testing device and a focusing horizontal goaf multi-row grouped column testing method.
Disclosure of Invention
The invention aims to provide a device and a method for testing the tensile strength of multiple rows of group columns in a horizontal goaf under the influence of disturbance, in particular to a device for realizing synchronous loading of multiple coal, rock, filling bodies, concrete, coal-filling and rock-filling test pieces, which can obtain the mutual influence relationship among the group column individuals, lay a foundation for revealing the chain instability response characteristics and mechanism of the stope group columns and provide guidance for the research and development of the stope group column chain instability prevention and control technology.
The invention provides a testing device for the tensile strength of multiple rows of grouped columns in a horizontal goaf under the influence of disturbance, which comprises: the device comprises a base, a rack, a lower loading jaw, an upper pressing plate, a workbench, a cross frame, a main loading rod, a main loading oil cylinder, a pressure sensor, a force control device, a protection ring, a half ball seat, an upper pressing plate and a directional bearing;
four protection rings are arranged on the base of the testing machine, a frame is arranged in each protection ring, the bottom end of each frame is connected with the base, the top end of each frame is connected with the transverse frame,
the bottom of the workbench is provided with a plurality of groups of force control devices which are arranged in parallel, wherein each force control device comprises a main loading rod, a main loading oil cylinder and a pressure sensor; the bottom of the transverse frame is provided with a plurality of groups of force disturbance devices which are arranged in parallel, and each force disturbance device comprises a disturbance force sensor, a disturbance oil cylinder and a disturbance rod; the worktable is positioned in the middle, five rows of lower loading jaws are uniformly arranged on the worktable, an upper loading jaw is arranged above the lower loading jaw in a matched manner, the upper loading jaw and the lower loading jaw are connected through a directional bearing, a sample is placed between the upper loading jaw and the lower loading jaw, a half ball seat is arranged in the center of the top of the upper loading jaw, and the force transmitted by the upper pressure plate is concentrated on a straight line where the half ball seat is contacted with the lower loading jaw, so that the stress of the sample is uniform.
The lower loading jaw is welded on the workbench, tensile capacity testing can be simultaneously carried out on 1-25 test pieces, and the length and the width of the lower loading jaw are 150mm and 150mm respectively; the length and width of the working table are 1000mm and 200mm respectively.
Preferably, the cluster column comprises: the method is suitable for the group columns with circular cross sections, the group columns with rectangular cross sections, and the group columns with triangular or trapezoidal cross sections.
Preferably, the device and the method are suitable for the goaf formed after the mining of the nearly horizontal coal seam with the inclination angle of less than 5 degrees.
Preferably, the device comprises 1-25 groups of force control devices, and each group of force control device comprises a pressure sensor, a main loading oil cylinder and a main loading rod. The pressure sensor is connected with the microcomputer through the control circuit, the stress state of each test piece can be accurately controlled, the loading with the same speed and different speeds can be carried out on different test pieces, and the pressure sensor is used for simulating the conditions of uniform stress and non-uniform stress of the test pieces.
Preferably, the device comprises 1-25 groups of force disturbance devices, each group of force disturbance device comprises a disturbance force sensor, a disturbance oil cylinder and a disturbance rod, the disturbance load is applied through the disturbance oil cylinder at the top of the testing machine, and then the disturbance rod acts on the sample, so that cosine wave, triangular wave and square wave axial disturbance loads can be applied to the sample.
Preferably, the upper loading jaw and the lower loading jaw are connected through a directional bearing, and an oval cavity is formed inside the upper loading jaw and the lower loading jaw after the upper loading jaw and the lower loading jaw are buckled and is used for placing a test piece and preventing the test piece from being subjected to eccentric load.
Preferably, the upper platen is divided into two types, one for studying the load bearing capacity of multiple specimens to share the overlying load, and one for studying the load bearing capacity of a single specimen simultaneously.
Preferably, the device can be used for testing the tensile test of a plurality of groups of columns, can also be used for the tensile test of a single column, and can be used for researching the tensile capability of a single coal, rock, filling body, concrete, coal-filled and rock-filled sample, and can also be used for researching the tensile capability of a plurality of single coal, rock, filling body, concrete, coal-filled and rock-filled group column systems.
The upper press plates are matched with the samples, the number of the upper press plates is three, the types of the upper press plates are selected according to experimental requirements, the first type is an integral upper press plate with the length and the width of 5000mm and 5000mm respectively, the second type is a single-row upper press plate with the length and the width of 1000mm and 150mm respectively, the third type is a single-body upper press plate with the length and the width of 150mm and 150mm respectively, the first type of upper press plate is used for researching the bearing capacity of the multi-row samples for bearing the overburden load together, the second type of upper press plate is used for researching the bearing capacity of the single-row samples for bearing the overburden load together, and the third type of upper press plate is used for testing the single-bearing capacity of the multiple samples simultaneously.
The invention provides a method for testing the tensile strength of multiple rows of grouped columns in a horizontal goaf under the influence of disturbance, which comprises the following steps:
the method comprises the following steps: the distribution position, the form and the size of the remaining grouped pillars in the horizontal goaf in the range to be tested are comprehensively investigated by utilizing the original geological technical data of the mine and by means of a supplementary exploration technical means;
step two: determining the shape, size and number of the test sample to be tested based on the information of the horizontal goaf remaining cluster columns obtained in the step one;
step three: drilling a sample with a proper size by using a special core drilling machine for coal rock and in a multi-stage variable speed manual feeding mode, and cutting and polishing the sample to the shape and size required by a test by using a coal rock cutting machine;
step four: sequentially mounting the sample on a lower loading jaw on a workbench;
step five: drawing two parallel loading baselines at two ends of the test piece along the axial direction, placing two pad strips along the loading baselines, and fixing the two pad strips through upper and lower loading jaws;
step six: determining the type of the upper pressing plate according to experimental requirements, selecting a first type of upper pressing plate when testing the carrying capacity of the multi-row samples for jointly bearing the overlying load, selecting a second type of upper pressing plate when testing the carrying capacity of the single-row samples for jointly bearing the overlying load, and selecting a third type of upper pressing plate when testing the single-row bearing capacity of the multiple samples;
step seven: placing the selected upper pressing plate above the hemispherical seat, and enabling the central line of the upper pressing plate and the central line of the sample to be tested to be located on the same plane so as to ensure that the sample to be tested is stressed uniformly; step eight: clearing the force value of each sensor to zero, and preloading;
step nine: after the preloading is finished, the loading speed of each hydraulic pushing shaft is set respectively for loading;
step ten: when the axial loading is carried out to the target value, the disturbance rod is utilized to apply axial disturbance load according to the test requirement;
step eleven: continuously applying axial load, and when the bearing capacity of the multiple rows of samples for jointly bearing the overlying load is tested, the multiple rows of samples are loaded to be integrally unstable; when the bearing capacity of the overlying load is commonly borne by the single-row test samples, the single-row test samples are loaded to each row of test samples to be subjected to overall instability; when the single bearing capacity of a plurality of samples is tested simultaneously, all the samples are loaded to be instable, or the loading is stopped after the test requirements are met;
step twelve: after loading is finished, the hydraulic pushing shaft is controlled by the hydraulic oil cylinder to unload, and the test is finished.
The invention has the beneficial effects that:
the invention can realize the simultaneous loading of a plurality of coals, rocks, filling bodies, concrete, coal-filling and rock-filling, further realize the simulation of the loading and the damage of a plurality of body remained ore pillars, and can realize the loading of uniform and non-uniform loads of a plurality of groups of pillars through a plurality of main loading rods, thereby researching the tensile capacity of a plurality of groups of pillar systems.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a schematic view of a first type of upper platen in accordance with the present invention;
FIG. 3 is a schematic view of a first type of upper platen loading configuration for use with the present invention;
FIG. 4 is a schematic view of a second type of upper platen working scenario for the present invention;
FIG. 5 is a schematic view of a second type of upper platen loading configuration for use with the present invention;
FIG. 6 is a schematic view of a third type of upper platen working scenario of the present invention;
FIG. 7 is a schematic view of a third type upper platen loading configuration for use with the present invention;
fig. 8 is a cross-sectional view of the loading device of the present invention.
In the figure: 1-tester base; 2, a frame; 3, loading a jaw; 4-loading the jaw; 5, an upper pressing plate; 6, a workbench; 7-horizontal frame; 8-main loading rod; 9-main loading oil cylinder; 10-a pressure sensor; 11-disturbance force sensor; 12-a guard ring; 13-half ball seat; 14-an upper platen; 15-a directional bearing; 16-disturbance oil cylinder; 17-a disturbance rod; 18-sample.
Detailed Description
The present invention is further illustrated by, but is not limited to, the following examples.
Example 1:
as shown in fig. 1 to 8, a device and a method for testing the tensile strength of multiple rows of grouped columns in a horizontal goaf under the influence of disturbance are characterized by comprising: the testing machine comprises a testing machine base 1, a rack 2, a lower loading jaw 3, an upper loading jaw 4, an upper pressure plate 5, a workbench 6, a cross frame 7, a main loading rod 8, a main loading oil cylinder 9, a pressure sensor 10, a disturbance force sensor 11, a protection ring 12, a hemispherical seat 13, an upper pressure plate 14, a directional bearing 15, a disturbance oil cylinder 16 and a disturbance rod 17.
The tester is characterized in that four protection rings 12 are arranged on a tester base 1, a frame 2 is installed in each protection ring 12, the bottom end of each frame 2 is connected with the tester base 1, the top end of each frame 2 is connected with a cross frame 7, and the bottom of a workbench 6 is provided with a plurality of groups of force control devices which are arranged in parallel and comprise a main loading rod 8, a main loading oil cylinder 9 and a pressure sensor 10; the bottom of the cross frame 7 is provided with a plurality of groups of force disturbance devices which are arranged in parallel, and each force disturbance device comprises a disturbance force sensor 11, a disturbance oil cylinder 16 and a disturbance rod 17; the working table 6 is located in the middle, five rows of lower loading jaws 3 are uniformly arranged on the working table 6, an upper loading jaw 4 is arranged above the lower loading jaw 3 in a matched mode, the upper loading jaw and the lower loading jaw are connected through a directional bearing, a sample 18 is placed between the upper loading jaw and the lower loading jaw, a half ball seat 13 is arranged in the center of the top of the upper loading jaw 4, force transmitted by the upper pressing plate 5 is concentrated on a straight line where the half ball seat 13 is in contact with the lower loading jaw 3, and therefore the stress of the sample is uniform.
Preferably, five rows of lower loading jaws 3 are arranged on the workbench, each row comprises five lower loading jaws, and 1-25 coal, rock and filling bodies can be loaded simultaneously, as shown in fig. 2.
Preferably, the centre points of the lower load jaws 3 are located on the same line, as shown in figure 1.
Preferably, each upper pressure plate 4 is connected with a main loading rod 7, so that loading with the same or different speed can be performed on different test pieces, and the conditions of uniform stress and non-uniform stress of the test pieces are simulated, as shown in fig. 1.
Preferably, the upper loading jaw 4 and the lower loading jaw 3 are connected through a directional bearing, the upper loading jaw and the lower loading jaw are connected through a directional bearing, and an oval cavity is formed inside the buckled upper loading jaw and lower loading jaw for placing a test piece and preventing the test piece from being subjected to eccentric load.
Preferably, the device can be used for uniaxial compression of a group of columns, the load transmitted by the upper pressing plate is jointly borne by the group of columns, and the tensile capacity of a group of column systems can be researched.
Example 2:
as shown in fig. 1, 3 and 5, a device and a method for testing the tensile strength of multiple rows of grouped columns in a horizontal goaf under the influence of disturbance are characterized by comprising the following steps: the testing machine comprises a testing machine base 1, a frame 2, a lower loading jaw 3, an upper loading jaw 4, an upper pressure plate 5, a workbench 6, a cross frame 7, a main loading rod 8, a main loading oil cylinder 9, a pressure sensor 10, a force control device 11, a protection ring 12, a hemispherical seat 13, an upper pressure plate 14 and a directional bearing 15. The base 1 is provided with four protection rings 12, a frame 2 is arranged inside each protection ring 12, one end of each frame 2 is connected with the base 1, the other end of each frame is connected with a cross frame 7, the lower part of each cross frame 7 is connected with five main loading rods 8, and each pushing shaft 8 is connected with an upper pressure plate 14.
Preferably, the centre points of the lower load jaws 3 are located on the same line, as shown in fig. 1
Preferably, each upper pressure plate 4 is connected with a main loading rod 7, so that loading with the same or different speed can be performed on different test pieces, and the conditions of uniform stress and non-uniform stress of the test pieces are simulated, as shown in fig. 1.
Preferably, a pressure sensor 10 is arranged inside each main loading rod 8, so that the stress state of each test piece can be accurately controlled respectively, as shown in fig. 1.
Preferably, the test device comprises twenty-five groups of force disturbance devices, each group of force disturbance device comprises a disturbance force sensor, a disturbance oil cylinder and a disturbance rod, the disturbance load is applied through the disturbance oil cylinder at the top of the test machine, and the axial disturbance load with the wave form of cosine wave, triangular wave and square wave can be applied to the test piece under the action of the disturbance rod on the test sample.
Preferably, twenty-five lower loading jaws 3 are arranged on the workbench 5, 1-25 coal, rock and filling bodies can be loaded simultaneously, and the experimental efficiency is greatly improved, as shown in fig. 4.
Preferably, the upper loading jaw 4 and the lower loading jaw 3 are connected through a directional bearing, the upper loading jaw and the lower loading jaw are connected through a directional bearing, and an oval cavity is formed inside the buckled upper loading jaw and lower loading jaw for placing a test piece and preventing the test piece from being subjected to eccentric load.
The upper pressure plates are of three types, the types of the upper pressure plates are selected according to experiment requirements, the first type is an integral upper pressure plate with the length and the width being 5000mm and 5000mm respectively, the second type is a single-row upper pressure plate with the length and the width being 1000mm and 150mm respectively, the third type is a single-body upper pressure plate with the length and the width being 150mm and 150mm respectively, the first type of upper pressure plate is used for researching the bearing capacity of a plurality of rows of samples for bearing the overlying load together, the second type of upper pressure plate is used for researching the bearing capacity of a single row of samples for bearing the overlying load together, and the third type of upper pressure plate is used for testing the single-bearing capacity of a plurality of samples simultaneously.
The invention provides a method for testing the tensile strength of multiple rows of grouped columns in a horizontal goaf under the influence of disturbance, which comprises the following steps:
the method comprises the following steps: the distribution position, the form and the size of the remaining grouped pillars in the horizontal goaf in the range to be tested are comprehensively investigated by utilizing the original geological technical data of the mine and by means of a supplementary exploration technical means;
step two: determining the shape, size and number of the test sample to be tested based on the information of the horizontal goaf remaining cluster columns obtained in the step one;
step three: drilling a sample with a proper size by using a special core drilling machine for coal rock and in a multi-stage variable speed manual feeding mode, and cutting and polishing the sample to the shape and size required by a test by using a coal rock cutting machine;
step four: sequentially mounting the sample on a lower loading jaw on a workbench;
step five: drawing two parallel loading baselines at two ends of the test piece along the axial direction, placing two pad strips along the loading baselines, and fixing the two pad strips through upper and lower loading jaws;
step six: determining the type of the upper pressing plate according to experimental requirements, selecting a first type of upper pressing plate when testing the carrying capacity of the multi-row samples for jointly bearing the overlying load, selecting a second type of upper pressing plate when testing the carrying capacity of the single-row samples for jointly bearing the overlying load, and selecting a third type of upper pressing plate when testing the single-row bearing capacity of the multiple samples;
step seven: placing the selected upper pressing plate above the hemispherical seat, and enabling the central line of the upper pressing plate and the central line of the sample to be tested to be located on the same plane so as to ensure that the sample to be tested is stressed uniformly;
step eight: clearing the force value of each sensor to zero, and preloading;
step nine: after the preloading is finished, the loading speed of each hydraulic pushing shaft is set respectively for loading;
step ten: when the axial loading is carried out to the target value, the disturbance rod is utilized to apply axial disturbance load according to the test requirement;
step eleven: continuously applying axial load, and when the bearing capacity of the multiple rows of samples for jointly bearing the overlying load is tested, the multiple rows of samples are loaded to be integrally unstable; when the bearing capacity of the overlying load is commonly borne by the single-row test samples, the single-row test samples are loaded to each row of test samples to be subjected to overall instability; when the single bearing capacity of a plurality of samples is tested simultaneously, all the samples are loaded to be instable, or the loading is stopped after the test requirements are met;
step twelve: after loading is finished, the hydraulic pushing shaft is controlled by the hydraulic oil cylinder to unload, and the test is finished.
The above is an embodiment of the present invention, and it should be noted that the present invention is not limited to the above embodiment, and may be simply modified according to the substance of the present invention, which all fall within the technical scope of the present invention.
Claims (8)
1. The utility model provides a disturbance influences lower horizontal goaf multirow crowd's post tensile strength testing arrangement which characterized in that includes: the testing machine comprises a testing machine base (1), a rack (2), a lower loading jaw (3), an upper loading jaw (4), an upper pressure plate (5), a workbench (6), a cross frame (7), a force control device, a force disturbance device, a protection ring (12), a hemisphere base (13), an upper pressure plate (14) and a directional bearing (15);
four protection rings are arranged on the base of the testing machine, a frame is arranged in each protection ring, the bottom end of each frame is connected with the base, the top end of each frame is connected with the transverse frame,
the bottom of the workbench is provided with a plurality of groups of force control devices which are arranged in parallel, wherein each force control device comprises a main loading rod, a main loading oil cylinder and a pressure sensor; the bottom of the transverse frame is provided with a plurality of groups of force disturbance devices which are arranged in parallel, and each force disturbance device comprises a disturbance force sensor, a disturbance oil cylinder and a disturbance rod; the workbench is located in the middle, five rows of lower loading jaws are evenly arranged on the workbench, an upper loading jaw is arranged above the lower loading jaw in a matched mode, the upper loading jaw and the lower loading jaw are connected through a directional bearing, and an oval cavity is formed inside the buckled upper loading jaw and the buckled lower loading jaw and used for placing a test piece and preventing the test piece from being subjected to eccentric load.
2. The device for testing the multi-row grouped column tensile strength of the horizontal goaf under the influence of disturbance according to claim 1, characterized in that: the goaf is formed after the mining of a nearly horizontal coal seam with an inclination angle smaller than 5 degrees; the group column comprises one of a coal column group, an ore column group, a filling column group, a concrete column group, a coal column-filling column combined group column, an ore column-filling column combined group column and a coal column-concrete column combined group column, and the section of the group column is circular or rectangular or triangular or trapezoidal.
3. The device for testing the multi-row grouped column tensile strength of the horizontal goaf under the influence of disturbance according to claim 1, characterized in that: the lower loading jaw is welded on the workbench (6) and can simultaneously test the tensile capacity of 1-25 test pieces, and the length and the width of the lower loading jaw are respectively 150mm and 150 mm; the length and width of the working table are 1000mm and 200mm respectively.
4. The device for testing the multi-row grouped column tensile strength of the horizontal goaf under the influence of disturbance according to claim 1, characterized in that: the device comprises 1-25 groups of force control devices, wherein each group of force control device comprises a pressure sensor (10), a main loading oil cylinder (9) and a main loading rod (8), the pressure sensors are connected with a microcomputer through control circuits, the stress state of each test piece can be accurately controlled respectively, the same and different loading speeds of different test pieces can be realized, and the device is used for simulating the conditions that the stress of the test pieces is uniform and the stress is not uniform.
5. The device for testing the multi-row grouped column tensile strength of the horizontal goaf under the influence of disturbance according to claim 1, characterized in that: the device comprises 1-25 groups of force disturbance devices, each group of force disturbance device comprises a disturbance force sensor, a disturbance oil cylinder (16) and a disturbance rod (17), the disturbance load is applied through the disturbance oil cylinder at the top of the testing machine, then the disturbance rods act on a test sample, and the axial disturbance load with the wave form of cosine waves, triangular waves and square waves is applied to the test sample.
6. The device for testing the multi-row grouped column tensile strength of the horizontal goaf under the influence of disturbance according to claim 1, characterized in that: the semi-ball seat is arranged at the center of the top in the upper loading jaw, and the force transmitted by the upper pressure plate is concentrated on a straight line where the semi-ball seat is contacted with the lower loading jaw, so that the stress of the test piece is uniform.
7. The device for testing the multi-row grouped column tensile strength of the horizontal goaf under the influence of disturbance according to claim 1, characterized in that: the upper pressure plates are of three types, the types of the upper pressure plates are selected according to experiment requirements, the first type is an integral upper pressure plate with the length and the width being 5000mm and 5000mm respectively, the second type is a single-row upper pressure plate with the length and the width being 1000mm and 150mm respectively, the third type is a single-body upper pressure plate with the length and the width being 150mm and 150mm respectively, the first type of upper pressure plate is used for researching the bearing capacity of a plurality of rows of samples for bearing the overlying load together, the second type of upper pressure plate is used for researching the bearing capacity of a single row of samples for bearing the overlying load together, and the third type of upper pressure plate is used for testing the single-bearing capacity of a plurality of samples simultaneously.
8. A method for testing the tensile strength of multiple rows of grouped columns in a horizontal goaf under the influence of disturbance adopts the device for testing the tensile strength of multiple rows of grouped columns in the horizontal goaf under the influence of disturbance, which is characterized by comprising the following steps:
the method comprises the following steps: the distribution position, the form and the size of the remaining grouped pillars in the horizontal goaf in the range to be tested are comprehensively investigated by utilizing the original geological technical data of the mine and by means of a supplementary exploration technical means;
step two: determining the shape, size and number of the test sample to be tested based on the information of the horizontal goaf remaining cluster columns obtained in the step one;
step three: drilling a sample with a proper size by using a special core drilling machine for coal rock and in a multi-stage variable speed manual feeding mode, and cutting and polishing the sample to the shape and size required by a test by using a coal rock cutting machine;
step four: sequentially mounting the sample on a lower loading jaw on a workbench;
step five: drawing two parallel loading baselines at two ends of the test piece along the axial direction, placing two pad strips along the loading baselines, and fixing the two pad strips through upper and lower loading jaws;
step six: determining the type of the upper pressing plate according to experimental requirements, selecting a first type of upper pressing plate when testing the carrying capacity of the multi-row samples for jointly bearing the overlying load, selecting a second type of upper pressing plate when testing the carrying capacity of the single-row samples for jointly bearing the overlying load, and selecting a third type of upper pressing plate when testing the single-row bearing capacity of the multiple samples;
step seven: placing the selected upper pressing plate above the hemispherical seat, and enabling the central line of the upper pressing plate and the central line of the sample to be tested to be located on the same plane so as to ensure that the sample to be tested is stressed uniformly;
step eight: clearing the force value of each sensor to zero, and preloading;
step nine: after the preloading is finished, the loading speed of each hydraulic pushing shaft is set respectively for loading;
step ten: when the axial loading is carried out to the target value, the disturbance rod is utilized to apply axial disturbance load according to the test requirement;
step eleven: continuously applying axial load, and when the bearing capacity of the multiple rows of samples for jointly bearing the overlying load is tested, the multiple rows of samples are loaded to be integrally unstable; when the bearing capacity of the overlying load is commonly borne by the single-row test samples, the single-row test samples are loaded to each row of test samples to be subjected to overall instability; when the single bearing capacity of a plurality of samples is tested simultaneously, all the samples are loaded to be instable, or the loading is stopped after the test requirements are met;
step twelve: after loading is finished, the hydraulic pushing shaft is controlled by the hydraulic oil cylinder to unload, and the test is finished.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110151070.7A CN112903452B (en) | 2021-02-04 | 2021-02-04 | Device and method for testing tensile capacity of multi-row group columns of horizontal goaf under influence of disturbance |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110151070.7A CN112903452B (en) | 2021-02-04 | 2021-02-04 | Device and method for testing tensile capacity of multi-row group columns of horizontal goaf under influence of disturbance |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112903452A true CN112903452A (en) | 2021-06-04 |
| CN112903452B CN112903452B (en) | 2023-10-10 |
Family
ID=76121898
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110151070.7A Active CN112903452B (en) | 2021-02-04 | 2021-02-04 | Device and method for testing tensile capacity of multi-row group columns of horizontal goaf under influence of disturbance |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112903452B (en) |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0979960A (en) * | 1995-09-08 | 1997-03-28 | Mitsui Constr Co Ltd | Splitting tensile testing device |
| CN101813587A (en) * | 2010-04-09 | 2010-08-25 | 长春市华宇试验机有限公司 | Manifold rock mass simulation test detection equipment |
| CN204128895U (en) * | 2014-09-01 | 2015-01-28 | 中国建筑材料科学研究总院 | The constant compressive stress charger of concrete |
| CN105910909A (en) * | 2016-03-29 | 2016-08-31 | 中国地震局地壳应力研究所 | Multi-diameter rock core dual-ring direct tension rock tensile strength tester |
| CN106226156A (en) * | 2016-09-21 | 2016-12-14 | 中国矿业大学(北京) | A kind of coal rock specimen fixture under the conditions of coupled static-dynamic loadingi |
| CN205898549U (en) * | 2016-06-23 | 2017-01-18 | 吴江市建设工程质量检测中心有限公司 | Marshall stability test appearance |
| JP2017219338A (en) * | 2016-06-03 | 2017-12-14 | 株式会社Ihi | Tensile test device and test piece evaluation system |
| CN107727569A (en) * | 2017-09-30 | 2018-02-23 | 华北水利水电大学 | A kind of test method for testing rock and concrete binding interface tensile strength |
| CN110082227A (en) * | 2019-04-22 | 2019-08-02 | 太原理工大学 | Simulate the residual exploiting field coal column group of dynamic loading tool post formula stable tester and its method |
| AU2019101006A4 (en) * | 2019-09-04 | 2019-10-10 | The University Of Adelaide | Snap-Back Indirect Tensile Test |
-
2021
- 2021-02-04 CN CN202110151070.7A patent/CN112903452B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0979960A (en) * | 1995-09-08 | 1997-03-28 | Mitsui Constr Co Ltd | Splitting tensile testing device |
| CN101813587A (en) * | 2010-04-09 | 2010-08-25 | 长春市华宇试验机有限公司 | Manifold rock mass simulation test detection equipment |
| CN204128895U (en) * | 2014-09-01 | 2015-01-28 | 中国建筑材料科学研究总院 | The constant compressive stress charger of concrete |
| CN105910909A (en) * | 2016-03-29 | 2016-08-31 | 中国地震局地壳应力研究所 | Multi-diameter rock core dual-ring direct tension rock tensile strength tester |
| JP2017219338A (en) * | 2016-06-03 | 2017-12-14 | 株式会社Ihi | Tensile test device and test piece evaluation system |
| CN205898549U (en) * | 2016-06-23 | 2017-01-18 | 吴江市建设工程质量检测中心有限公司 | Marshall stability test appearance |
| CN106226156A (en) * | 2016-09-21 | 2016-12-14 | 中国矿业大学(北京) | A kind of coal rock specimen fixture under the conditions of coupled static-dynamic loadingi |
| CN107727569A (en) * | 2017-09-30 | 2018-02-23 | 华北水利水电大学 | A kind of test method for testing rock and concrete binding interface tensile strength |
| CN110082227A (en) * | 2019-04-22 | 2019-08-02 | 太原理工大学 | Simulate the residual exploiting field coal column group of dynamic loading tool post formula stable tester and its method |
| AU2019101006A4 (en) * | 2019-09-04 | 2019-10-10 | The University Of Adelaide | Snap-Back Indirect Tensile Test |
Non-Patent Citations (2)
| Title |
|---|
| GONG FENG-QIANG ET AL.: "Brazilian disc test study on tensile strength-weakening effect of high pre-loaded red sandstone under dynamic disturbance", 《J. CENT. SOUTH UNIV》, pages 2899 - 2913 * |
| 申辰 等: "酸液对煌斑岩抗拉力学性能的影响及机理分析", 《太原理工大学学报》, vol. 48, no. 3, pages 407 - 412 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112903452B (en) | 2023-10-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110274831B (en) | Device and method for testing anchor rod (cable) supporting structure and comprehensively testing performance of anchor system | |
| CN112858013A (en) | Device and method for testing tensile resistance of multiple rows of grouped columns in inclined goaf | |
| CN103471914B (en) | Rock burst true triaxial simulation experiment system | |
| CN110243701B (en) | Torsion shear test device and method for anchored rock mass | |
| CN112903463B (en) | Double-shaft static force-disturbance coupling inclined goaf group column bearing test device and method | |
| CN102879547A (en) | Three-direction loading large-scale three-dimensional analog simulation test counterforce system | |
| CN105067438A (en) | Model testing device capable of applying three-axis stress for tunnel dislocation destruction when movable fault zone is penetrated | |
| CN108489797B (en) | Large-dip-angle coal rock stratum mechanical property physical simulation and test device | |
| CN113049780A (en) | Testing device and testing method for gangue fluidized filling material | |
| CN112082859A (en) | Simulation method for guaranteeing mine double-level double-stage mining safety | |
| CN112903454B (en) | Horizontal goaf multi-row group column tensile strength testing device and method | |
| CN106979888A (en) | Study the test apparatus and test method of ore pillar digging process obturation carrying mechanism | |
| CN102879550A (en) | Load simulation method for triaxially loading large-scale three dimensional similitude simulation test | |
| CN106601111A (en) | Large true-triaxial simulation test stand for tunnel roof support | |
| CN112903452A (en) | Device and method for testing tensile strength of multiple rows of grouped columns in horizontal goaf under influence of disturbance | |
| CN210136143U (en) | Torsion shear test device for anchored rock mass | |
| CN112903465B (en) | Device and method for testing double bearing capacity of single-row group columns in inclined goaf | |
| US11788930B2 (en) | Device and method for testing bearing capacity of single-row grouped pillars in horizontal goaf under biaxial loading | |
| CN103971585A (en) | Device and method for simulation test of load-carrying property of gob-side entry retaining anchoring pack wall | |
| CN111855416A (en) | Circulating shear test device under stretching condition and application method thereof | |
| CN112903461A (en) | Device and method for testing multi-row group column uniaxial bearing capacity of goaf under influence of disturbance | |
| CN203825944U (en) | Gob-side entry retaining anchoring spoil wall bearing performance simulation tester | |
| CN112903460B (en) | Device and method for testing multi-row group column single-shaft bearing of inclined goaf under influence of disturbance | |
| CN112903464B (en) | Device and method for testing single-row group column double-shaft bearing capacity of goaf under influence of disturbance | |
| CN112881191A (en) | Device and method for testing loading capacity of multi-row group column single bearing in horizontal goaf |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |