JP3750043B2 - Large section underground hollow quarry - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a large section underground air HoraHara stone quarry to give a rough particularly drilling large section underground cavities, harmonization and effective use of underground natural environment further allowed the backfill Ore surplus soil It relates to the rough quarry.
[0002]
[Prior art]
A sub-level stopping method is known as an economical large-scale mining method for mining ore in a mine. In this sub-level stopping method, an unloading tunnel is excavated in advance at the bottom of the ore body to be mined, and multiple sub-levels (horizontal tunnels) are placed in the ore body that extends above. Excavate to the position, and lower the board by blasting from the bottom near the lower level face by bench-cut blasting etc., drop the excavated ore into the hopper part constructed by widening the upper part of the unloading mineway, the lower end of the hopper part The ore is pulled out from the draw point, and the ore is carried out to the pit by a mining car or the like through a carry-out mine shaft.
[0003]
In this sub-level stopping method, underground cavities can be excavated on a large scale and at a low cost, so it is used as a rational and effective mining method especially for deposits that are plate-shaped and are located vertically. It has been.
[0004]
[Problems to be solved by the invention]
In the mine, in order to efficiently perform the mining work, the support work is not performed on the cavity excavated by the sub-level stopping method, and the rock mass is in an exposed digging state. For this reason, the actual situation is that no measures are taken against the collapse of the cavity after excavation. In addition, there is a sufficient risk of ground subsidence due to loose rock around the cavity. Therefore, the ore digging by the conventional mining method can be performed only under the condition that the influence of the land subsidence etc. is not exerted by others after the mining right of the target land is established. In order to prevent such a situation as much as possible, in many cases, the excavated trace cavity is filled with ore waste after the beneficiation to stabilize the excavated trace cavity. However, in this case, since the cavity was backfilled with ore waste, the underground cavity after mining could not be used for other purposes.
[0005]
By the way, at present, in construction work such as rockfill dams, rough stones as the building material of the dam body are collected by cutting up the mountain near the site. However, such roughing is accompanied by large-scale mountain cuts, which can significantly damage the environment around the site. For example, wildlife such as golden eagles and bear hawks are threatened, and there are concerns about various adverse effects on the ecosystem. In fact, construction projects have been delayed for more than a few years to deal with these problems, and there is a possibility that they may also be derived from problems in the construction of the dam itself. Therefore, it is desirable to take measures to minimize the natural destruction associated with the extraction of rough.
[0006]
Therefore, the object of the present invention is to solve the problems of the conventional techniques described above, and in excavation of underground cavities, excavation by the sub-level stoping method and appropriate surrounding rock mass support are performed. The object of the present invention is to provide a method for excavating a cavity and to provide a rough quarry where the stability of the rock mass is maintained after excavation using the method.
[0007]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the present invention excavates a plurality of rows of ore-drawing horizontal shafts at a predetermined position of a rock to be mined ore, and sets a plurality of levels of sub-levels in such a direction as to cross the rough-drawing horizontal shaft. Excavated at a predetermined interval in the vertical direction of the sub-level, constructing a hopper portion that communicates the lowermost level of the sub-level and the draw-out horizontal pit, the upper rock is the free surface of the tip of the lower-level sub-level The rough is mined as if it is lowered by a bench cut from the vicinity, and the mined rough is carried out from the hopper part via the rough draw-out horizontal shaft, while the lower cut by the bench cut is in the vertical position. Among the levels, the mining at the upper sub-level is performed to follow the sub-level mining located at the lower side, and the mining cavities mined by the multi-stage bench cut are at each sub-level. A rough quarry where a large cross-section underground cavity is formed that is widened upward in a stepped shape with a step, while the large cross-section underground cavity is mainly backfilled with residual rough ore, and the bench When drilling a cut blast hole, the blast hole at the location where the bad rock is encountered in the rock is extended to the length required to reinforce the bad rock located outside the final excavation surface with a rock bolt. Drilling holes, placing rock bolts in the holes, charging them to a predetermined range in front of the final excavation surface and using them as blast holes , and existing in the rock to be collected The defective layer is a columnar portion integrated with the surrounding healthy rock mass, and the rock mass of the columnar portion is left without being mined .
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the large section underground air HoraHara stone quarry of the present invention will be described with reference to the accompanying drawings.
Each drawing in FIG. 1 is a schematic explanatory view schematically showing an excavation state of a reference example of an embodiment by an excavation method for mining in a large cross-section underground hollow ore mine of the present invention. Three levels of sub-level tunnels 2 (2A, 2B, 2C) are excavated along the vertical direction of the rock to be excavated. In each sub-level tunnel 2, as shown in FIG. 1 (b), the bench cut board is lowered by radial blasting from the face toward the lower rock, and the generated gap is excavated in the lower part of the underground cavity 1A. It is carried out to the outside of the pit through the horizontal pull-out horizontal pit 4 and the auxiliary pit 5. At this time, using the blast hole 3 drilled from each sub-level tunnel 2 as shown in FIG. 1 (c), a rock bolt 7 is applied to the bedrock outside the final excavation surface 6 of the underground cavity 1. Yes. As a result, when the cross-section is widened from the sub-level tunnel 2 that functions as a guide shaft, support is achieved by the rock bolt 7 installed deeper than the final excavation surface 6 of the underground cavity 1. Moreover, about the cavity top end part, as shown in FIG.1 (c) similarly, the lock bolt 8 is constructed and the stability of a cavity is ensured.
[0012]
[Reference example]
Below, the excavation procedure of the rough quarry of the underground cavity 1 according to the present invention will be described with reference to FIGS. In FIG. 2 to FIG. 9, description will be made on the assumption that mining cavity excavation is performed using the two-stage sub-level tunnel 2. In addition, in the following reference examples, since the excavation method is described, the gap to be carried out in the explanation corresponds to the raw stone to be carried out.
[0013]
2 shows, as a reference example of a drilling method of mining cavity, underground cavity 1 is shown by a two-dot chain line in the rock. The auxiliary mine 5 is excavated from the ground well (not shown) along the longitudinal direction of the underground cavity 1. The auxiliary mine 5 is excavated along the underground cavity 1 by a predetermined distance, and is used as a path for carrying out a gap generated when the underground cavity 1 is excavated later and a path for carrying in an excavating machine. . Further, as shown in FIG. 2, from the side surface of the auxiliary pit 5, the number of lower slidable horizontal pits 4 equal to the number of slot-shaped hopper portions 9 (see FIG. 1 (a)) constructed in the lower part of the underground cavity 1A are excavated. . The slip-out horizontal pit 4 is set to be smaller than the tunnel cross section of the auxiliary mine 5, but it is preferable to have a cross section in which a track having a predetermined capacity of a mining vehicle and a battery locomotive can be installed.
[0014]
First, the first sub-level tunnel 2 </ b> A is excavated from the ground well side (not shown) at the stage where the pull-out horizontal shaft 4 which is the innermost side from the well hole is excavated over the entire width B of the underground cavity 1. The first sub-level tunnel 2 </ b> A is a tunnel parallel to the auxiliary mine 5 described above, and its cross section is set slightly smaller than the tunnel cross section of the auxiliary mine 5. It has a cross section to the extent that a traveling track such as a vehicle equipped with an excavating machine can be laid in the same manner as the sliding pull-out horizontal shaft 4. As shown in FIG. 3, the first sub-level tunnel 2 </ b> A is excavated until the face reaches the innermost side of the underground cavity 1. The first sub-level tunnel 2A is preferably provided at a position approximately half the height H of the underground cavity 1 as shown.
[0015]
Subsequently, the second sub-level tunnel 2B is excavated at a position where the top portion of the underground cavity 1 and the top portion thereof coincide with each other so as to be vertically positioned with respect to the first sub-level tunnel 2A (see FIG. 4). In the present embodiment, excavation is performed using the first and second sub-level tunnels 2A and 2B as guide shafts, but the number of sub-level tunnels 2 is set according to the scale of the excavation cross section of the underground cavity 1. It is preferable to set appropriately. Moreover, in the excavation from the sub-level tunnel 2 in each stage, the sub-level tunnel 2 is used as a survey mine for geological survey, and the distribution status of the geological weak layer such as the fracture zone is grasped by the rock observation. This result is extended to the final excavation surface 6 to predict the geological distribution on the final excavation surface 6.
[0016]
Subsequently, as shown in FIG. 5, upward blasting is performed for excavating the slot-like hopper portion 9 by drilling the blasting hole 3 upward from the sliding pull-out horizontal shaft 4 at the tip position of the first sub-level tunnel 2A. . As shown in FIG. 5, the hopper portion 9 has a horizontal triangular prism shape with the sloping pull-out horizontal shaft 4 as a lower end position, and the top end of the sloping pull-out horizontal shaft 4 is penetrated over the entire width B of the underground cavity 1 at the completion of excavation. Slot 9a is constructed. The slip generated later is piled up so as to be accumulated in the hopper portion 9, and a part of it drops in the slot 9 a and is piled up in the pull-out horizontal shaft 4. The shape and gradient of the hopper portion 9 can be set according to the direction and the drilling pattern of the drilling rod when drilling the blasting hole 3 of the upward blasting from the sliding pull-out horizontal shaft 4. It is preferable to set the gradient of the hopper portion 9 to be larger than the angle of repose of the slip.
[0017]
Subsequently, a bench cut from the vicinity of the face of the first sub-level tunnel 2A toward the hopper portion 9 is started. In this bench cut, the hopper portion 9 that has already been excavated is located below the bedrock, so that it falls from the hopper portion 9 of the spill generated by the blasting to the slid pull-out horizontal shaft 4.
[0018]
In addition, when the existence of a weak layer 20 such as a crushing zone that crosses the underground cavity 1 is clear according to the bedrock condition already confirmed during the excavation of the sub-level tunnel 2, the blast hole 3 is formed as shown in FIG. Further, it is preferable to carry out drilling as a hole 21 for extending the lock bolt. And the inner part of the excavation surface 6 of the hole 21 in which the lock bolt 7 is laid is used as a blast hole 3 for bench cutting.
That is, the drilling length of the bench-cut blast hole 3 drilled from the sub-level tunnel 2 has a range in which the weak layer portion 20 (see FIG. 1C) that crosses the sub-level tunnel 2 is distributed. In this case, as shown in FIGS. 6 and 7, the length is obtained by adding a length corresponding to the length of the lock bolt to be driven outside the final excavation surface 6. That is, a hole is drilled to such a depth that the fixing portion of the rock bolt 7 is located at a rock position where the weak layer portion 20 can be sufficiently reinforced. The drilling length in other healthy rocks may be up to the final excavation surface 6 for bench cutting. Then, a lock bolt 7 having a predetermined length is driven into the hole 21 targeted for the weak layer portion 20. As a rock bolt driving operation, first, a mortar injection hose (not shown) is inserted to the bottom of the hole to inject mortar into the hole 21, and then a lock bolt 7 is attached to the rod end of a hole drilling machine (not shown). Attach the lock bolt 7 to the back of the hole. Next, the hole 21 after the placement of the lock bolt 7 is idled again to near the excavation surface 6. Further, the inside of the hole 21 is cleaned, and this portion is used as the blast hole 3 for bench cutting. In order to ensure the stability of the cavity side wall, the lock bolt 7 (see FIG. 1 (c)) is applied to the final excavation surface near the level of the sub-level tunnel 2 by the same method. Is preferred. Moreover, about the cavity top end part, the lock bolt 8 (refer FIG.1 (c)) is constructed by the same method, and the stability of a cavity is ensured.
[0019]
In the state where the bottom excavation is performed by bench cutting to the final excavation surface 6, the head of the lock bolt 7 appears on the hollow wall surface. Therefore, shotcrete 25 (see FIG. 1C) having a predetermined thickness is applied to the cavity wall surface from the end of the sub-level tunnel 2. Since the sprayer (not shown) is installed in the sub-level tunnel 2, if there is a distance between the nozzle tip of the hose of the sprayer and the cavity wall surface, a long nozzle may be used as necessary. .
In addition, although the example of the rock reinforcement by the lock bolt 7 was described in the above description, the PC anchor using PC cable strand can also be used besides a lock bolt.
[0020]
FIG. 7 shows a state in which the large hopper portion 9 has been excavated from the face of the first sub-level tunnel 2A in the downward direction. Subsequently, the bench cut board is lowered from the second sub-level tunnel 2 </ b> B located at the upper part of the cavity of the hopper portion 9 toward the hopper portion 9. Also in this case, it is preferable to incorporate a process of lining the rock bolt 7 and the shotcrete 25 according to the surrounding rock mass. Further, the hopper portion 9 constructed in the first sub-level tunnel 2A by the bench cut shown in FIG. 7 is widened, and a slip can be dropped on the widened portion. It is discharged out of the mine via
[0021]
As shown in FIG. 1 (a) and FIG. 7, in the positional relationship between the first sublevel tunnel 2A and the second sublevel tunnel 2B, the blast excavation of the lower first sublevel tunnel 2A is always on the upper side. Prior to the second sub-level tunnel 2B, a bench cut from the upper second sub-level tunnel 2B is performed on the constructed hopper portion 9. By repeating the excavation cycle described above toward the wellhead side, a plurality of rows of slot-like hopper portions 9 can be constructed from the back side of the underground cavity 1 toward the wellhead side. Moreover, the large underground cavity 1 can be excavated safely and rapidly by lowering the upper rock using a multi-stage bench cut by using a plurality of sub-level tunnels 2. At this time, as shown in FIG. 8, a block 22 corresponding to the slot-like hopper portion 9 remains between the sliding pull-out horizontal shafts 4, but this block 22 is also cut by a normal blasting method in the final process. Thus, the underground cavity 1 as shown in FIG. 9 can be finally completed.
[0022]
As shown in FIG. 1 (c), the underground cavity 1 is provided with a predetermined lock bolt 7 to reinforce the weak layer 20 such as a crush zone of the surrounding rock mass, and further blown over the entire inner wall surface of the cavity. Since the lining with the attached concrete 25 is made, high stability is ensured in the completed state.
[0023]
The stability of the underground cavity 1 after excavation is determined by measuring the passage of time by installing measuring devices such as inclinometers (not shown) from the ground surface or upper tunnels, and observing the displacement of the interior sky, the deformation of the shotcrete surface. to manage. If the result of this measurement shows an internal deformation, displacement, or displacement speed that exceeds the measurement control standard, the lock bolt is installed by a lock bolt driving machine or spray machine mounted on an aerial work vehicle from the bottom of the cavity. Take measures to suppress the progression of deformation by increasing the number 7 and blowing the shotcrete 25 more.
[0024]
【Example】
10 to 12 show an embodiment in which the excavation method for the large-section underground cavity 1 shown above is applied to underground underground mining. That is, in order to solve the problem of mining methods cut through the conventional rough mountain has, Reference Examples using drilling methods of the large cross section underground cavities described, terrestrial environment rather name or to destroy the ore taken In addition, an embodiment of a rough quarry where the surrounding environment is prevented from deteriorating when the rough rough soil is treated by backfilling the rough rough soil is shown.
[0025]
As shown in FIG. 10, it is necessary to mine the raw stone in the raw quarry composed of the mining cavities 30 and extract it to the outside so as not to cause any trouble on the outside such as the ground surface. In this way, since the rough ore which has been conventionally handled as a slip is carried out to the outside, the above-described slip pull-out horizontal shaft 4 can be used as the rough ore pull-out horizontal shaft 14. In addition, as shown in FIG. 10, the unearthed residual soil 36 is introduced into the excavated mining cavity 30 from the top sublevel tunnel 2D, and after excavation, the cavity 30 is backfilled to stabilize the rock mass.
[0026]
The mining procedure of the raw ore mining pit composed of the mining cavity 30 in which quarrying is performed by the above-described excavation method of the large-section underground cavity will be briefly described.
After excavating the underground pit 5 and the ore-drawing horizontal pit 14 equivalent to those shown in FIGS. 2 and 3 for the underground rock mass judged to be suitable as a rough quarry, the multi-level sub-level gallery 2 is excavated. (See FIG. 4). This sub-level tunnel 2 is also used as a survey horizontal shaft for geological surveys, grasping the distribution of geological weak layers such as fracture zones, and extending this result to the final excavation surface 6 to Predict the dimensional geological structure.
[0027]
FIG. 11 is a schematic cross-sectional view of a mining cavity 30 showing an example in which a rock strut 31 as a columnar portion is constructed for a defective rock 20 that is determined to be unsuitable as a raw stone in the mining cavity 30 by geological observation. In the mining cavity 30, unlike the normal underground cavity 1 (see FIG. 1), it is possible to leave a portion where defective rock is distributed and not mine that portion. FIG. 11 shows an example in which a bad bedrock exists in the mining cavity 30 with a predetermined strike slope. As shown in the figure, for a weak layer 20 such as a crush zone which is suitable as a raw stone to be mined but is considered to have an influence on the stability of the underground cavity 1 after mining, FIG. As shown to (a), the rock strut 31 over the up-down direction of the mining cavity 30 is provided so that the weak layer part 20 extended in the strip | belt shape in the up-down direction may be enclosed with a healthy rock. The rock strut 31 enables mining excavation without exposing the weak layer portion 20 to the mining cavity 30, and can also suppress the looseness of the top end 30a of the cavity 30 to a minimum. Further, in the mining cavity 30 where the longitudinal extension of the cavity is increased, it is preferable to perform excavation by leaving the lock struts 31 at an appropriate interval.
[0028]
As a support means on the final excavation surface 6, it is preferable to prevent the progress of deformation and deformation of the cavity 30 by performing the above-described covering with the lock bolt 7 and the shotcrete 25.
[0029]
By the way, the mining cavity 30 can effectively use the trace of the mining. That is, as shown in FIG. 10 (left side in the figure) and FIG. 12, the remaining rough stones produced by the crusher and produced with the predetermined aggregate among the rough stones 35 carried out from the top sublevel tunnel 2D. The remaining soil 36 is thrown into the mining cavity 30 and the underground space is sequentially refilled. As shown in FIG. 12, the backfilling with the rough rough soil 36 is performed up to the vicinity of the top sub-level tunnel 2 </ b> C and used as a disposal site for the rough rough soil 36, and the arched ceiling portion 32 is left as an underground space for effective use. be able to.
[0030]
Specifically, in the mining cavity 30, as shown in FIG. 12, when the backfilling with the raw stone residual soil 36 reaches a predetermined height, the bottom plate made of the spread residual soil is compacted to a certain extent. After the ground strength is obtained, support by the lock bolt 8 and the shotcrete 25 is applied to ensure the safety of the arch ceiling portion 32. It is also possible to use a disposal space in which construction residual soil and the like can be dumped in addition to the raw stone residual soil 36.
[0031]
Thus, in the rough quarry where the underground mining cavity 30 is excavated and backfilled, it is not necessary to cut large-scale mountain topography on the ground in order to extract the rough, and the natural environment can be maintained. it can. In addition, if the raw ore residue 36 generated on site in the mining cavity 30 is sequentially backfilled, it is not necessary to secure a remaining soil disposal site in another place. Further, when the mining cavity 30 is backfilled with the unearthed residual soil 36, the ceiling space formed by the arch-shaped portion 32 is left on the upper portion of the mining cavity 30, and this space is used as a multipurpose underground space such as an underground warehouse, a management facility, and an exhibition hall. You can also.
[Brief description of the drawings]
FIG. 1 is a sectional view showing an embodiment of a method for excavating a large-section underground cavity according to the present invention.
FIG. 2 is an explanatory view (No. 1) showing an excavation procedure in an excavation method for an underground cavity having a large cross section.
FIG. 3 is an explanatory diagram (part 2) showing an excavation procedure in an excavation method for an underground cavity having a large cross section.
FIG. 4 is an explanatory view (No. 3) showing an excavation procedure in an excavation method for an underground cavity having a large cross section.
FIG. 5 is an explanatory diagram (part 4) showing a digging procedure in the excavation method for a large-section underground cavity.
FIG. 6 is an explanatory view (No. 5) showing the excavation procedure in the excavation method for a large-section underground cavity.
FIG. 7 is an explanatory view (No. 6) showing an excavation procedure in an excavation method for a large-section underground cavity.
FIG. 8 is an explanatory view (No. 7) showing the excavation procedure in the excavation method for a large-section underground cavity.
FIG. 9 is an explanatory view (No. 8) showing the excavation procedure in the excavation method for a large cross-section underground cavity.
FIG. 10 is a cross-sectional view showing an embodiment of a rough quarry with a mining cavity.
FIG. 11 is a cross-sectional view showing an example of a rock strut constructed in a rough quarry with a mining cavity.
FIG. 12 is a cross-sectional view showing a state in which a rough quarry with a mining cavity is backfilled with unearthed soil.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Underground cavity 2 Sub level 2A 1st sub level 2B 2nd sub level 2C, 2D Top sub level 3 Blast hole 4 Sliding extraction side pit 5 Auxiliary mine 6 Final excavation surface 7 Rock bolt (side wall part)
8 Rock bolt (top end)
9 Hopper portion 9a Slot 14 Roughing horizontal shaft 30 Mining cavity 35 Rough 36 Rough earth

Claims (1)

Excavate multiple rows of ore-drawing horizontal shafts at a predetermined position of the rock to be mined, and excavate multiple levels of sub-levels at predetermined intervals in the vertical direction of the rock in such a direction as to cross the original ore-exposed horizontal shaft And construct a hopper part in which the lowermost level of the sub-level and the rough drawing horizontal pit are communicated, and the upper rock is lowered by a bench cut from the vicinity of the free surface at the tip of the lowermost level While mining the rough stone, the mined rough is carried out from the hopper portion through the rough pull-out horizontal pit, while the down-cut mining by the bench cut is performed at a sub-level located on the upper side among the sub-levels in the vertical position. Mining is performed to follow the sub-level mining located below, and the excavation trace cavities mined by multi-stage bench cuts form a stepped shape with steps at each sub-level upward While forming a large section underground cavities widened towards, a gemstone mine which is adapted backfill the large section underground cavities by mainly rough surplus soil,
When drilling the blast hole of the bench cut, the blast hole of the place where the bad rock is encountered out of the rock is up to a length necessary to reinforce the bad rock located outside the final excavation surface with a rock bolt. Extending and drilling holes, placing lock bolts in the holes, charging them to a predetermined range in front of the final excavation surface, and using them as blast holes, in the rock to be collected the defective layer present, and healthy bedrock integral with the columnar portion of the periphery thereof, a large cross section underground air HoraHara stone quarry, characterized in that the leaving without mining the rock of the columnar portion.

Images