JPS6220357B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for constructing a vertical shaft that can safely and rationally construct a hole of a desired depth in rock.

Traditionally, in order to build a shaft in bedrock, the 12th
As shown in Figures 1 to 17, a series of operations such as drilling a blast hole, blasting, unloading, and lining the shaft are repeated in each stage from the ground surface downward.

In this method, one stage's worth of blast holes are drilled when sequentially excavating each stage, but the holes around the shaft a are drilled through the concrete b of the lining wall of the stage immediately above, which was previously formed. Due to the presence of the excavation wall, etc., it is not possible to perpendicularly drill holes along the planned excavation wall surface, and the holes must be drilled at an angle. Therefore, since this inclined hole c is necessarily located outward from the planned excavation line, the excavation cross section d becomes large and the amount of lining concrete used increases.

In addition, for unloading work, after one stage of blasting work is completed, the load must be transported to the shaft entrance using an appropriate lifting and lowering device, and the equipment for this is large-scale. There was a problem that the work required a long time.

For this reason, a new excavation method as shown in FIGS. 18 to 24 has recently been developed.

This method is used when excavating a vertical shaft f that is connected to a horizontal shaft e that has already been excavated.
A predetermined number of blasting holes g penetrating from the ground surface into the horizontal shaft e are drilled in advance in the peripheral area of the planned hole cross section and the interior surrounded by the peripheral area, and the required amount of explosives is placed in the lower part of each blasting hole. After loading, the explosives were detonated almost simultaneously to complete the blasting of one stage of the lower part of the shaft, and the 〓 produced by the blasting was transported outside using the side shaft.
Discharge. Thereafter, explosives are again loaded into the appropriate locations in the blast hole g, and the blast is discharged, and this operation is repeated to form a vertical shaft f that reaches the ground surface from the horizontal shaft e side.

Next, assemble the elevating scaffold i in the shaft f and
Concrete k is placed sequentially from the lower or upper side using formwork j to line the vertical shaft f.

According to this construction method, both the amount of excavation and the amount of concrete are as planned compared to the above method, but it requires a lifting scaffold i for assembling formwork and pouring concrete, and requires work at heights. This poses a safety problem, and furthermore, after excavation, the rock mass on the shaft wall becomes stressed and released because the water is completely discharged.
Since it takes a considerable amount of time to completely line the shaft with concrete, a loose area m is formed in the rock around the shaft.

For this reason, it is necessary to increase the wall thickness of the lining concrete k, and especially when building a shaft with a large cross section, the formation of the loosened area m becomes noticeable, so it is no longer possible to adopt this construction method. It is considered a problem.

In order to eliminate such problems, the present invention has the following features:
In this construction method, a rock hole of a desired depth is excavated while blasting explosives at appropriate lengths in the depth direction. Only the blast holes provided on the outer periphery other than the center of this planned shaft are filled with filler such as sand, and the lower part of each blast hole provided in the center of the planned shaft is filled with filler such as sand. Explosives are loaded from the ground surface and then detonated to form a central shaft of an appropriate height that communicates with the horizontal shaft.
A central shaft is formed by repeating the above-mentioned blasting in an upward direction from the lower part of the central part of the shaft, reaching the ground surface, and then the filling material in the blast hole filled with the sand, etc. is deposited on the ground surface. A suitable length portion is removed from the shaft, an explosive is loaded, the explosive is detonated, and the 〓 generated by the blasting is expelled into the central shaft, and this blasting operation is repeated successively moving down the central shaft. The present invention provides a rock excavation method characterized by forming a large-diameter shaft and discharging the waste that has been removed into a central shaft from a side shaft.

To explain the embodiment of the present invention with reference to the drawings, as shown in FIGS. 1 to 11, there is a space between a ground surface 2 of a bedrock 1 and a horizontal shaft 3 provided at an appropriate depth from this ground surface 2. This is a method of constructing a vertical shaft 4 with a large cross section.

First, as shown in FIG. 1, a plurality of blast holes 6 are penetrated and drilled in the outer periphery of the planned shaft and its inner side from the ground surface 2 toward the horizontal shaft 3 using the poling machine 5. For this blasting hole 6, if a plurality of coring holes 6a and blowing holes 6b are arranged in the central part of the planned shaft as shown in FIG. In this case, the lower end is closed with a plug 11, and the inside thereof is filled with sand 7 over its entire length.

Furthermore, a wooden plug 12 having a diameter slightly smaller than that of each blast hole 6a, 6b in the central part of the planned shaft not filled with sand 7 is suspended from the ground surface 2 with a rope 13.

At the center of the lower end of this stopper 12, as shown in FIG. 11, approximately the center of a rod-shaped material 14, which is longer than the diameter of the blasting hole 6, is suspended by a string 15, and a string is formed on the upper surface. A ring 16 is attached to the ring 16, and a hook 17 attached to the lower end of the rope 13 is hooked onto the ring 16, and the rope 13 is suspended into the blast hole 6.

At this time, the rod-shaped material 14 is suspended in the blast hole 6 in an inclined state, and when it reaches the inside of the horizontal shaft 3, it becomes approximately horizontal.

When the rope 13 is pulled up from this state, the bar 14 comes into contact with the upper wall of the shaft and is locked, and the plug 12 is stopped at a predetermined position at the lower end of the blast hole 6. Then the 10th
As shown in the figure, an appropriate amount of ballast 18 is placed inside the blast hole 6.
The plug 12 is inserted into the hole 6 by inserting the ballast 18 into the space between the inner circumferential wall of the hole 6 and the plug 12.
is fixed and held, then the rope 13 is loosened and the hook 17 is removed from the ring 12, and the rope 13 is
Collect.

Next, while measuring from the ground surface, an appropriate amount of ballast 18 and a fuse 1 are placed in each blast hole 6a, 6b in the center.
Explosive 19 and tamping material 20 connected to 9' are set.

In this way, all the holes 6a, 6b in the central part of the planned holes
After loading explosives 19 into the specified part of the
When these explosives 19 are exploded almost simultaneously, the lower center of the planned vertical shaft 4 of one stage 21 leading to the horizontal shaft 3 is excavated and formed (FIG. 3). The 〓22 generated by this blasting is discharged to the outside through the horizontal shaft 3, but the amount is only the increased amount of 〓 generated by the blasting of the next stage 23, and the predetermined amount is A cavity 24 of an appropriate size is created between the lower end surface of the stage 23 and the top end of the stage 23 to be formed next. Once this cavity 24 is formed, a new plug 12 with a rod-shaped material 14 suspended therein is suspended again in the blast holes 6a, 6b, the rod-shaped material 14 is locked to the ceiling wall surface of the cavity 24, and the ballast 18 is inserted. As described above, the cavity 2 of each blast hole 6a, 6b is
The plug 12 is fixed at a predetermined length above the stage 4, and the next stage 20 is blasted and excavated by charging and blasting.

This blasting work is carried out to all the blasting holes 6a, 6 in the central part.
By repeating the process upwards every predetermined length, a vertical shaft 4' with a small cross section filled with 22 up to the top is created at the center of the planned vertical shaft on the ground surface 2 and the horizontal shaft 3.
(Fig. 4).

In this way, a small-diameter shaft 4' is excavated leaving a certain width a around the planned large-section shaft 4, so even if all the water in the small-diameter shaft 4' is discharged, the surrounding rock The loosened region due to stress release can be contained within the above-mentioned remaining range a.

Next, an appropriate amount of 〓 is discharged from the horizontal hole 3 side, and the top of the shaft 4' is lowered by one stage from the ground surface to form a burn hole 25, and inside the blast holes 6c, 6d on the outer periphery. After removing the sand 7 by a length corresponding to one stage using compressed air or high-pressure water, the required amount of explosives 26 is loaded into the hollow lower part and exploded, and the area surrounding the planned shaft and the central shaft 4 is removed. ' Break down the bedrock between. At this time, the 〓 that occurred is
By discharging an appropriate amount from the horizontal shaft 3, the top is lowered, and the small-diameter shaft 4' created by the lowering
One stage of excavation is completed, and a scaffolding 27 is formed (FIGS. 5 and 6).

Thereafter, the upper part of the large cross-section shaft is lined by driving lock bolts 28, spraying concrete, or placing concrete 29 using a formwork.

Next, in the same manner as described above, the sand in the blasting holes 6c and 6d is removed by a desired length, charged and blasted, and the resulting sand is poured into the small-diameter shaft 4' into the recess formed by the descent of the top. It will be used to form scaffolding and line the large-section shaft.

By repeating this operation sequentially from the ground surface toward the horizontal shaft 3, a vertical shaft 4 with a large cross section is constructed as shown in FIG.

In the above embodiments, sand was used as the material to fill the blast holes, but any material may be used as long as it can be easily removed with compressed air, high pressure water, or the like.

As described above, the present invention is a method of excavating a rock hole of a desired depth while blasting explosives at appropriate lengths in the depth direction. Before proceeding, the required number of blast holes will be penetrated and drilled in the planned shaft part, and only the blast holes provided on the outer periphery other than the central part of the planned shaft will be filled with filler such as sand, and Explosives are loaded from the ground surface into the lower part of each blast hole provided and then blasted to form a central shaft of an appropriate height that communicates with the horizontal shaft. By repeating the blasting, a central shaft reaching the ground surface is formed, and then the filling material in the blast hole filled with sand, etc. is removed from the ground surface by an appropriate length, and explosives are loaded. The explosives are blasted and the resulting blast is expelled into the central shaft, and this blasting operation is repeated successively toward the bottom of the central shaft to form a large-diameter shaft. Since this involves a rock hole excavation method characterized by discharging water from a horizontal shaft, the required number of long blast holes are drilled in the planned hole according to the depth of the hole planned in advance. This prevents the amount of excavation and concrete from exceeding the planned amount, and the work can be done more efficiently than when drilling holes for each stage. The bottom surface of holes of a predetermined depth formed at predetermined length intervals can be used as scaffolding, making it possible to perform lining work safely and efficiently without the need for conventional lifting and lowering scaffolding. . Furthermore, since the blast holes provided on the outer periphery of the planned shaft other than the central area are filled with filler such as sand, there is no risk that the blast holes will be filled by sand when blasting is carried out. During the next blasting operation, the open end of the blast hole can be easily found and explosives can be loaded smoothly.

Further, according to the present invention, after forming the central shaft, the diameter of the surrounding area is sequentially expanded by blasting at appropriate depths from the ground surface, so that it is possible to easily construct a shaft with a large cross section. When the shaft is formed, the surrounding rock remains, so a rock loosening area due to stress release can be formed in the remaining part, and the rock around the large cross-section shaft does not loosen.
Therefore, the thickness of the lining of the inner circumferential wall of the shaft can be made thinner. Moreover, since the lower end of the central shaft is connected to a pre-prepared horizontal shaft and the 〓 can be discharged from the lateral shaft, there is no need for lifting equipment for discharging the 〓, and the 〓 can be discharged from the lined concrete. This method can shorten the construction period because it can be carried out within the curing time of It is possible to lower the top of the shaft by discharging it from the side shaft, and to throw the debris produced by blasting into the recess that is created at that time.This makes it easy to discharge the debris, and it also makes it easier to use the scaffolding when forming a large-section shaft. It is easy to form and enables smooth concrete lining work.

[Brief explanation of the drawing]

Figures 1 to 11 show an embodiment of the present invention, Figures 1 to 8 are process diagrams, Figure 9 is a plan view showing the drilling state of the blast hole, and Figure 10 is the loading of explosives. A vertical sectional view showing the state, FIG. 11 is a front view of the stopper,
Figures 12 to 17 are simplified process diagrams of the conventional method;
18 to 22 are simplified process diagrams of another conventional construction method, FIG. 23 is a plan view showing the drilling state of the blast hole, and FIG. 24 is a plan view showing the loosened region. 1... Bedrock, 2... Ground surface, 3... Side shaft, 4...
...shaft, 6...blast hole, 7...sand, 19...explosives, 22...〓.

Claims (1)

[Claims] 1. In a method of excavating a rock hole of a desired depth while blasting explosives at appropriate lengths in the depth direction, the necessary amount is A number of blast holes will be penetrated and drilled, and filler such as sand will be filled only in the blast holes provided on the outer periphery other than the center of the planned shaft, and each blast hole provided in the center of the planned shaft will be filled with filler such as sand. By loading explosives from the ground surface at the bottom of the shaft and blasting them to form a central shaft of an appropriate height that communicates with the horizontal shaft, the blasting is repeated for each stage upward from the bottom of the central shaft. A central shaft reaching the earth's surface is formed, and then a suitable length of the filling material in the blast hole filled with sand, etc. is removed from the earth's surface, explosives are loaded, and the explosives are detonated. The 〓 generated by the blasting is expelled into the central shaft, and this blasting work is repeated successively downward in the central shaft to form a large-diameter shaft, and the 〓 expelled into the central shaft is removed from the side shaft. A rock excavation method characterized by discharge.