Method for monitoring parameters of goaf filling body under roof crushing condition

Abstract

The invention discloses a goaf filling body parameter monitoring method under a roof breaking condition, and relates to the technical field of mineral exploitation, and the method comprises the following steps: designing a monitoring interval corresponding to each roof stability grade on a roof along a horizontal working surface of the roof; punching is conducted according to the monitoring interval corresponding to the top plate stability level of the top plate, punching is conducted through the false top into the immediate top, a punching burying layer is arranged in the immediate top, punching is conducted through the immediate top into the basic top, and a punching burying layer is arranged in the basic top; an induction ring of the split type displacement sensor is buried in the punching burying layer so as to measure the compression deformation amount of the filling body; a nest groove is formed in the ground below the embedded position of the induction ring, and a stress meter is arranged in the nest groove to measure the stress of the filling body. The method can adaptively and accurately monitor the parameters of the goaf filling body.

Description

Technical Field

[0001] The invention relates to the technical field of mineral mining, and in particular to a method for monitoring filling body parameters in a goaf under a roof crushing condition. Background Art

[0002] Solid filling coal mining technology is a revolutionary technology in filling mining technology. It uses the filling body in the goaf to control the movement of the goaf roof. It has the advantages of improving resource recovery rate, solid waste disposal and environmental protection. It is the preferred technology for liberating "three-down" compressed coal and other stagnant coal resources. The parameters of the goaf filling body in solid filling coal mining technology are important factors affecting the filling effect and controlling the filling cost.

[0003] When encountering roof crushing conditions, the existing technology for monitoring the backfill parameters of the goaf cannot adapt to the roof of the goaf under roof crushing conditions. When the roof is crushed and falls, errors will occur in the monitored backfill parameters. How to design a backfill parameter monitoring method to adapt to the roof under roof crushing conditions is an important issue that needs to be solved urgently. Summary of the invention

[0004] The embodiment of the present invention provides a method for monitoring backfill parameters of a goaf under roof crushing conditions, which can solve the problem in the prior art of how to design a backfill parameter monitoring method to adapt to a roof under roof crushing conditions.

[0005] An embodiment of the present invention provides a method for monitoring filling parameters of a goaf under roof crushing conditions, comprising the following steps: Under the condition of broken roof, the roof of the goaf is divided into multiple roof stability levels and classified; wherein, the classification includes a pseudo roof, a direct roof located above the pseudo roof, and a basic roof located above the direct roof; along the horizontal working surface of the roof, a monitoring interval corresponding to each roof stability level is designed on the roof; holes are drilled according to the monitoring interval corresponding to the roof stability level of the roof, holes are drilled through the pseudo roof to the direct roof, a perforated buried layer is set in the direct roof, and holes are drilled through the direct roof to the basic roof, and a perforated buried layer is set in the basic roof; in the roof where the perforated buried layer is set, the induction ring of the split displacement sensor is buried in the perforated buried layer to measure the compression deformation of the filling body; a groove is set on the ground below the buried position of the induction ring, and a stress gauge is set in the groove to measure the stress of the filling body; the split sensor and the stress gauge are connected by an armored cable; the split sensor and the stress gauge are used to continuously monitor the filling body parameters of the goaf respectively.

[0006] Furthermore, the monitoring interval corresponding to each roof stability level is designed on the roof, and the specific steps include: According to the hardness of the roof, the roof is divided into hard roof, stable roof, medium stable roof and unstable roof; on the hard roof, the monitoring interval is set to half the length of the working face; on the stable roof, the monitoring interval is set to one quarter of the length of the working face; on the medium stable roof, the monitoring interval is set to one sixth of the length of the working face; on the unstable roof, the monitoring interval is set to one eighth of the length of the working face.

[0007] Furthermore, the socket has a size of 800 mm×800 mm.

[0008] Furthermore, before continuously monitoring the filling parameters of the goaf, the split sensor and the stress gauge need to be sealed, reinforced and protectively filled.

[0009] Furthermore, the split sensor and the strain gauge are sealed, reinforced and protectively filled, and the specific steps include: sealing the connection port of the armored cable by a waterproof foaming agent, and sealing the split sensor and the strain gauge with a waterproof foaming agent; and reinforcing the split sensor by grouting in the hole.

[0010] The embodiment of the present invention provides a method for monitoring filling parameters of a goaf under roof crushing conditions. Compared with the prior art, the method has the following beneficial effects: Under the condition of broken roof, a monitoring interval corresponding to each roof stability level is designed on the roof of the goaf along the horizontal working surface of the roof; holes are drilled according to the monitoring interval corresponding to the roof stability level of the roof, holes are drilled through the pseudo-top to the direct roof, a hole-burying layer is set in the direct roof, and holes are drilled through the direct roof to the basic roof, a hole-burying layer is set in the basic roof; in the roof where the hole-burying layer is set, the induction ring of the split displacement sensor is buried in the hole-burying layer to measure the compression deformation of the filling body; a groove is set on the ground below the buried position of the induction ring, and a stress gauge is set in the groove to measure the stress of the filling body; the split sensor and the stress gauge are connected by an armored cable; the split sensor and the stress gauge are used to continuously monitor the filling body parameters of the goaf respectively.

[0011] Among them, taking into account the possibility of roof falling under the condition of roof crushing, the drilling position and drilling burying layer are adaptively set to install the monitoring equipment according to the roof stability level of the goaf; when the hole is drilled into the direct roof, even if the pseudo-top part falls, it will not affect the monitoring equipment; when the hole is drilled into the basic roof, even if the direct top part falls, it will not affect the monitoring equipment; the monitoring of the monitoring equipment is avoided to be affected by the falling of the roof, and finally according to the roof of the goaf under the condition of roof crushing, the equipment installation position can be adaptively selected to monitor the filling body parameters of the goaf. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1A flowchart provided for an embodiment of the present invention; Figure 2 A plan view of the arrangement of a goaf filling monitoring device provided in an embodiment of the present invention; Figure 3 AA cross-sectional view of the arrangement of the goaf filling monitoring equipment provided by the embodiment of the present invention; Figure 4 A diagram showing the connection method of the goaf filling monitoring equipment provided in an embodiment of the present invention.

[0013] Reference numerals: 5-goaf area behind the frame, 2-split displacement sensor, 3-stress gauge, 4-induction ring, 5-grouting hole, 6-armored cable containing magnetic induction wire, 7-measuring rod, 8-probe, 9-mortar, 10-pressure-resistant waterproof box, 11-base, 12-displacement sensor armored cable, 13-stress sensor armored cable, 14-data acquisition instrument, 15-junction box. DETAILED DESCRIPTION

[0014] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0015] See also Figure 1 The embodiment of the present invention provides a method for monitoring filling parameters of a goaf under roof crushing conditions, comprising the following steps: Step 1: Obtain the roof occurrence conditions of the goaf under the roof crushing condition, and divide the roof into multiple roof stability levels and classify the roof according to the roof occurrence conditions. Among them, the occurrence conditions represent the geological characteristics and state of the covering layer above the goaf as the roof, and the classification includes the pseudo-roof, the direct roof above the pseudo-roof, and the basic roof above the direct roof.

[0016] Step 2: Along the horizontal working surface of the roof, design monitoring intervals corresponding to each roof stability level on the roof; drill holes according to the monitoring intervals corresponding to the roof stability level of the roof, drill holes through the pseudo-top to the direct top, set a perforated buried layer in the direct top, and drill holes through the direct top to the basic top, set a perforated buried layer in the basic top.

[0017] Step 3: In the top plate where the perforated buried layer is set, bury the induction ring of the split displacement sensor in the perforated buried layer to measure the compression deformation of the filling body; under the top plate where the induction ring is buried, set a groove on the ground, and set the strain gauge in the groove to measure the stress of the filling body; the split sensor and the strain gauge are connected through an armored cable. The split sensor and the strain gauge are sealed, reinforced and protectively filled, specifically including: sealing the connection port of the armored cable with a waterproof foaming agent, and sealing the split sensor and the strain gauge with a waterproof foaming agent; grouting in the hole to reinforce the split sensor. Fill the goaf, and use the split sensor and the strain gauge to continuously monitor the parameters of the filling body in the goaf.

[0018] Among them, the roof is divided into hard roof, stable roof, medium stable roof and unstable roof according to its hardness; on the hard roof, the monitoring interval is set to half of the length of the working face; on the stable roof, the monitoring interval is set to one quarter of the length of the working face; on the medium stable roof, the monitoring interval is set to one sixth of the length of the working face; on the unstable roof, the monitoring interval is set to one eighth of the length of the working face.

[0019] The specific execution steps are explained as follows: (1) On-site investigation: analyze the existence and integrity of the roof in the goaf behind the support, and obtain the direct fall height of the roof in different areas.

[0020] (2) Design of monitoring scheme: Design the monitoring spacing according to the stability level of the roof; design the buried layer of the induction ring of the split displacement sensor according to the direct fall height of the roof. Specifically, when the direct fall height of the roof is within the pseudo-roof, the drilling buried layer is designed to be within the direct roof; when the direct fall height of the roof is within the direct roof, the drilling buried layer is designed to be within the basic roof.

[0021] (3) Reserve space for laying pipelines. Place four adjacent brackets on the left and right sides of the installation position and fully compact them. Then move the brackets forward by three rows. During the movement, only fill the non-installation area.

[0022] (4) Clean the gangue and arrange the installation groove. Arrange the groove at the bottom of the monitoring equipment installation position. The size of the groove is 800mmx800mm. The depth is required to see the bottom (plate) or a certain thickness of gangue bottom can be reserved, and the bottom of the groove should be cleaned and leveled.

[0023] (5) Monitoring equipment installation: a vertical hole is drilled upward in the middle of the adjacent brackets at the installation location, and a split displacement sensor is arranged in the hole; the strain gauge is arranged in the groove of the bracket base close to the goaf side; the split displacement sensor and the strain gauge are connected by armored cables and connected together to the junction box in the pressure-resistant waterproof box.

[0024] (6) Safety protection of monitoring equipment: Use waterproof foaming agent to seal the interface between the cable and the monitoring equipment, split displacement sensor, stress gauge, pressure-resistant waterproof box, and reinforce the arranged drilled holes by grouting.

[0025] (7) Transmission line layout: After the monitoring equipment cable is integrated through the junction box, the armored cable in the goaf behind the frame is laid on the lower side of the top beam behind the support, and the armored cable inside the tunnel is hung at 2 / 3 of the height of the tunnel wall.

[0026] (8) Equipment debugging: the protective part is filled within 500mm from the monitoring device. Equipment debugging specifically means that after the equipment is installed, other positions on the working surface begin to be filled normally. The 3 to 5 groups of brackets on the left and right of the equipment installation position continue to place only gangue within 2 steps, and the compaction mechanism is not turned on for compaction. After the brackets have been moved twice and the monitoring position is about 500mm outside the full stroke of the compaction head of the compactor, the 3 to 5 groups of brackets on the left and right of the equipment installation position can be filled normally.

[0027] (9) Continuous monitoring and normal filling. The filling parameters include filling body stress and filling body compression deformation. The filling body parameter monitoring equipment includes stress gauges and split displacement sensors.

[0028] The present invention takes split measurement as the core, and forms a full-time method flow design including pre-monitoring preparation, monitoring equipment installation, monitoring and debugging, etc. It mainly includes 8 steps, including on-site investigation, design of monitoring plan, pre-installation preparation of monitoring equipment, monitoring equipment installation, monitoring equipment safety protection, data transmission safety protection, equipment debugging, and continuous monitoring, which ultimately achieves safe and reliable monitoring of backfill parameters in goaf under broken roof conditions and sustainable data transmission. The present invention expands the monitoring scenarios of backfill parameters in backfill mining, and provides a scientific, reasonable, safe and reliable method for backfill parameter monitoring in goaf under broken roof conditions, providing underlying parameters for improving the efficiency, benefits, effects and engineering design optimization of backfill mining, and facilitating the high-quality and wide-range development of backfill mining technology.

[0029] A specific embodiment is as follows: (1) On-site investigation: Analysis of the roof conditions and integrity of the goaf 1 behind the frame, and the direct fall height of the roof in different areas.

[0030] (2) Design a monitoring plan. In the working face of the intact roof area, backfill parameter monitoring equipment (split displacement sensor 2 and stress gauge 3) is evenly spaced at intervals of 30 m. In the broken roof area, the monitoring plan is increased. In the middle part near the broken area, a set of monitoring equipment (split displacement sensor 2 and stress gauge 3) is added. Since the caving area only affects the pseudo-roof, the split displacement sensor 2 is designed to be buried in the direct roof.

[0031] (3) Preparation before installation: reserve space for laying pipelines and clean up the waste rock to arrange the installation pits.

[0032] (4) Monitoring equipment installation: the split displacement sensor 2 is installed in the hydraulic support room, and the strain gauge 3 is arranged at the rear of the hydraulic support. The split displacement sensor and the strain gauge are connected through the displacement sensor armored cable 12 and the stress sensor armored cable 13, and are connected together to the junction box 15 in the pressure-resistant waterproof box 10.

[0033] (5) Safety protection of monitoring equipment: Use waterproof foaming agent to seal the interface between the cable (displacement sensor armored cable 12 and stress sensor armored cable 13) and the monitoring equipment (split displacement sensor 2 and strain gauge 3), the split displacement sensor 2 and the pressure-resistant waterproof box 10, and inject mortar 9 to reinforce the arranged drilled holes 5. The arrangement of monitoring equipment is as follows: Figure 2 and Figure 3 As shown, the connection method is as follows Figure 4 shown.

[0034] (6) Safety protection of data transmission equipment. The armored cables in the working surface are laid at the rear of the bracket, and the armored cables inside the tunnel are hung on the side of the tunnel.

[0035] (7) Equipment debugging and protective part filling.

[0036] (8) Fill normally and monitor continuously.

[0037] In step (4), the split displacement sensor comprises 2, an induction ring 4, an armored cable 6 containing a magnetic induction wire, a measuring rod 7, a base 11 and a data acquisition device 14. The data acquisition device 14 of the split displacement sensor 2 is located in a pressure-resistant and waterproof box 10.

[0038] Among them, in step (7), equipment debugging specifically refers to that after the equipment is installed, other positions of the working face begin to be filled normally; 3 to 5 groups of brackets on the left and right of the equipment installation position continue to place only gangue within 2 steps, and do not start the compaction mechanism for compaction, so as to avoid the compaction head squeezing the gangue and pushing it down or directly pushing it to the top plate dynamic meter (column). After the brackets have been moved twice and the position of the dynamic meter (column) is ensured to be 500mm outside the full stroke of the compaction head of the compactor, the 3 to 5 groups of brackets on the left and right of the equipment installation position can be filled normally.

[0039] The present invention effectively solves the problem that it is difficult to safely, accurately and efficiently monitor the filling body parameters of the goaf under the condition of roof crushing. Through targeted investigation of the roof collapse situation and design of the corresponding installation and layout method, the split displacement sensor is innovatively selected and installed between the hydraulic support frames to ensure that the equipment is completely under the protection of the hydraulic support during installation. Through process innovation, the monitoring of the filling body parameters of the goaf under the condition of roof crushing becomes a reality, which effectively quantifies the range of activity of the overlying rock strata that restricts the mining area, and is conducive to promoting the development of solid filling technology.

[0040] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for monitoring backfill parameters in goaf under roof crushing conditions, characterized in that: The following steps are involved: Under the condition of roof crushing, the roof of the goaf is divided into multiple roof stability levels and the roof is classified; wherein the classification includes a false roof, a direct roof located above the false roof, and a basic roof located above the direct roof; Along the horizontal working surface of the roof, a monitoring spacing corresponding to each roof stability level is designed on the roof; Drill holes according to the monitoring spacing corresponding to the roof stability level of the roof, drill holes through the pseudo-roof to the direct roof, set a drilled buried layer in the direct roof, and drill holes through the direct roof to the basic roof, set a drilled buried layer in the basic roof; In the top plate where the perforated buried layer is set, the induction ring of the split displacement sensor is buried in the perforated buried layer to measure the compression deformation of the filling body; a groove is set on the ground below the buried position of the induction ring, and a stress gauge is set in the groove to measure the stress of the filling body; the split sensor and the stress gauge are connected through an armored cable; Split sensors and stress gauges are used to continuously monitor the filling parameters of the goaf.

2. A method for monitoring backfill parameters in goaf under roof crushing conditions as claimed in claim 1, characterized in that: The specific steps of designing the monitoring spacing corresponding to each roof stability level on the roof include: According to the hardness of the roof, the roof is divided into hard roof, stable roof, medium stable roof and unstable roof; On a hard top plate, set the monitoring interval to half the length of the working surface; On a stable roof, set the monitoring interval to one-quarter of the length of the working face; On a moderately stable roof, set the monitoring interval to one-sixth of the length of the working face; On unstable roof, set the monitoring interval to one eighth of the working face length.

3. The method for monitoring backfill parameters of goaf under roof crushing conditions as claimed in claim 1, characterized in that: The socket size is 800mm×800mm.

4. The method for monitoring backfill parameters of goaf under roof crushing conditions as claimed in claim 1, characterized in that: Before the continuous monitoring of the filling parameters of the goaf, the split sensor and the stress gauge need to be sealed, reinforced and protectively filled.

5. The method for monitoring backfill parameters of goaf under roof crushing conditions as claimed in claim 4, characterized in that: The steps of sealing, reinforcing and protectively filling the split sensor and the strain gauge include: The connection port of the armored cable is sealed by a waterproof foaming agent, and the split sensor and strain gauge are also sealed by a waterproof foaming agent; The split sensor is reinforced by grouting in the hole.

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