US3098641A

US3098641A - Method of making holes in the earth

Info

Publication number: US3098641A
Application number: US71937A
Authority: US
Inventors: Ronald C Baldwin
Original assignee: Ingersoll Rand Co
Current assignee: Ingersoll Rand Co
Priority date: 1960-11-28
Filing date: 1960-11-28
Publication date: 1963-07-23
Anticipated expiration: 1980-07-23

Description

(.111 mmwmm July 23, 1963 R. c. BALDWIN 3,098,641

METHOD OF MAKING HOLES IN THE EARTH Filed Nov. 28, 1960 2 Sheets-Sheet 1 flgliff I; A 3' 2' BI 4| F/G.3 8'

INVENTOR c c RONALD c. aA pw/m WM HIS A T RNEY July 23, 1963 R. c. BALDWIN 3,093,641

METHOD OF MAKING HOLES IN THE EARTH Filed Nov. 28, 1960 2 Sheets-Sheet 2 FIG. /0

INVENTOR RO/VAL D 6. BALDWIN m HIS TTORNEY been set free by the blast.

United States Patent 3,098,641 METHOD OF MAKING HOLES IN THE EARTH Ronald C. Baldwin, Hillsdale, N.J., assignor to Ingersoll- Rand Company, New York, N.Y., a corporation of New Jersey Filed Nov. 28, 1960, Ser. No. 71,937 4 Claims. (Cl. 262-4) This invention relates to a method of making holes in the earth and is primarily concerned with a method of making a hole in a bed of rock.

More particularly the invention is concerned with a method which coordinates the performance of the various functions required to make a relatively large hole in a bed of rock.

In making these types of holes, several functions are required to be performed. For example, when a hole is to be made in a bed of rock, it is necessary to drill a series of blasting bores in which explosives may be inserted for blasting the rock. After the blasting occurs, it is necessary to remove the loosened rock which has This is usually accomplished by a powered digging machine having a scoop in the front which scoops up the loosened rock and deposits it in a bucket. A crane or other lifting device is used for lifting the bucket out of the hole and the loosened rock is dumped at the side of the hole or into trucks where it may be carried away. The removal of the loosened rock by these machines is known as mucking and the machines are known as muckers. As the hole is formed, it may be necessary to set steel along the vertical sides of the hole and also to line these sides with concrete.

The invention relates to a method for coordinating all of the above functions to obtain maximum efliciency of rock removal per unit of time. This is accomplished by removing the rock in such a way that the bottom surface of the hole is maintained in the shape of a spiral path with the spiral path starting and finishing at a vertical face. By maintaining this spiral bottom during the progress of the digging of the hole, it is possible to derive many advantages relating to the coordination of the various functions necessary to make the hole. The shape of the bottom of the hole is maintained as a spiral path until the depth of the hole desired has been reached, at which time, the bottom of the hole can be made level.

In the past it has been the practice to drill a series of blasting bores uniformly to a certain depth depending on the depth of rock desired to be loosened by the blast. The bores would be spaced uniformly around the bottom of the hole within the particular configuration of the hole to be made. In this previously known method, all the equipment would be removed from the hole before detonation of the explosives since the entire bottom of the hole was blasted and equipment left there would be damaged by the blast.

This known method had many disadvantages, one of the major ones being that all of the equipment would have to be removed from the hole during each blasting operation and then returned to the hole after the blasting has been completed. Also as the equipment was returned to the hole after a blast, it would be placed on a pile of loose rock which was loosened by the blast which would hinder the performance of the succeeding operations which were necessary to continue on with the hole. For example, it was diflicult for the muckers to ride on and dig into such a pile of loose rock. Also drilling could not be commenced until the loosened rock had been removed from the hole. f

This invention eliminates these disadvantages by providing an efficient method for performing all the operations simultaneously. V

Accordingly, an object of this invention is to provide an improved method of making a hole in the earth.

Another object of this invention is to provide a method of making a hole in the earth in which the bottom of the hole is maintained in the general form of a spiral path during the progress of removing material from the hole.

Another object of this invention is to provide a method whereby the functions necessary to form the hole may be accomplished simultaneously without interruption except during blasting.

Another object is to provide a continuous grade at the bottom of the hole whereby the muckers dig downgrade against a solid bottom at all times. 7

Another object is to provide a free face parallel to the blast holes to which all blasting may be accomplished.

The foregoing and other objects of this invention will be obvious from the descriptions and drawings wherein:

FIGURE 1 is a perspective view of the bottom of the hole at one stage of its formation.

FIGURE 2 is a plan view of the hole with various points on the circumference designated by letters.

FIGURE 3 is a graphic representation of the circumference of the hole laid out as a straight line with the depths of the hole indicated at various points on its circumference.

FIGURE 4 is similar to FIGURE 3 except the depths of hole at another stage of its formation are indicated.

'FIGURES 5-8 are plan views of the hole during various stages of its formation.

FIGURE 9 is a cross sectional view of the hole in FIGURE 8 taken along line 99.

FIGURE 10 is a plan view of the hole showing possible shapes of the vertical face.

In the present invention the bottom surface of the hole 10 is maintained in the form of a spiral path 12. Necessarily the starting point of the spiral path must be at a different elevation than its termination. This difference in elevation determines the height of the vertical face 13 whereby the spiral path commences at the upper edge 14 of the vertical face 13 and the terminates at the lower edge 15 of the vertical face. The bottom of the hole is maintained generally with the particular shape shown in FIGURE 1 at all times during the progress of the excavation. The method of maintaining this particular shaped bottom will be hereinafter described.

FIGURE 2 shows a plan view of the hole 10 with the circumference indicated at 16 while FIGURES 3 and 4 show the circumference 16 laid out as a straight line for the purposes of this description. The circumference 16 in FIGURE 2 is equal in length to the straight line 16 in FIGURES 3 and 4. The vertical lines in FIGURES 3 and 4 indicate the depth of the hole at the circumference at different stages of its formation. The spiral surface at the bottom of the hole graphically traces out on the circumferential wall of the hole a spiral path which commences at X1. The depth at the circumference gradually increases as the spiral is traced from X1 to A1 as indicated by the length of the vertical lines A1 and B1 in FIGURE 3. For the purposes of this illustration, eight feet has been selected as the depth to he traveled in making one complete revolution of the spiral. The depth of the hole at the circumference gradually increases as the spiral path is traced from A1 to G1. As the spiral further continues, it returns to its original circumferential point X1, X2. However, the depth at X2 is now 8 foot but since the spiral started out at the point X1 with an elevation of zero, there is a difference in depth of eight foot which corresponds to the height of the vertical face 13 shown in FIGURE 1.

FIGURE 4 illustrates the various depths of the hole as a second revolution of the spiral path is traced out. During the second revolution, the shape of the spiral is main- 3 tained by removing a constant depth of rock (in this case 8 feet as shown in FIGURE 4). The bottom of the hole at the circumference after the second revolution has been completed is designated by subscripts 2. Thus at A2 the depth of hole at the circumference will be 9 feet. The depth at point B2 will be 10 feet as indicated by B2. The depth increases at the circumference until the second spiral path is traced out back to the originating point X1, X2, X3. However, this second spiral started out at an elevation of 8 feet indicated at X2 whereas the termination of the spiral is at a depth of 16 feet indicated as X3. Thus the vertical face 13 still remains. The third revolution and fourth revolution and so on continue until the proper depth of the hole is reached. Thus it can be seen that the bottom of the hole is maintained at a slope at all times and that a vertical face is always present.

The coordination and performance of the various functions for making this hole in the shape and manner above described will now be explained in detail. For the purposes of this illustration the bottom of the hole has been divided into four sectors, each having a designated area for performing a specific function. However, it is to be understood that although the drawings and following description apply to four sectors, any number of sectors may be used as required. Also the shape of each sector may be varied as required.

In the bottom of the hole, while sector 20, which is adjacent to the vertical face 13, is being drilled with blasting bores 25 for explosives, muckers may be used to remove the broken rock loosened from a previous explosion in another sector 23 which is also adjacent the vertical face 13. Simultaneously steel and concrete may be set at the circumferential edge of the hole in

sectors

21 and 22. The muckers dig the loosened rock from sector 23 and dump it into a bucket which is hoisted out of the hole. All of these operations and any other necessary operations may be accomplished simultaneously.

After the blasting bores 25 have been drilled in sector it becomes necessary to detonate the explosives. During the blasting it will be necessary to interrupt the other functions being formed in other sectors of the hole. However, the equipment being used in the other sectors such as the muckers and drilling equipment do not have to be removed from the hole since only a portion of the hole is to be blasted as indicated by the sector 20. Thus it is possible to leave the equipment in the hole with a minimum of protection. The blasting is then commenced by first detonating a section 26 of the sector 20 immediately adjacent the vertical face 13 thus breaking and ejecting material from the face 13 to provide a swell space in section 26. After section 26 has been detonated, section 27 will be detonated, and the loosened rock in section 26 will not hinder the effectiveness of the blasting in section 27 due to the swell space in section 26. Similarly

sections

28 and 29 are detonated in that order. This series of detonations may be accomplished electrically at a time delay sequence. In this way each section is detonated against a muck pile, therefore providing efiicient use of the explosive and also reducing flying rock. Four sections 26 to 29 have been shown for the purposes of this illustration but it is to be understood that any number of sections may be used and blasted as required. Also the size and spacing of the blasting bores may be varied as required for proper fragmentation.

After the explosion has occurred, there remains a vertical face I13, as indicated in 'FIGURE 6. The sector area 20, which has just been blasted, now becomes the mucking sector as shown in FIGURE 6. Since the mucking operation was going on in sector 23 While the drilling was going on in sector 20, the operation may be timed such that the mucking in sector 23 will be completed at about the same time that the drilling in sector 20 is completed. Thus after the blasting of sector 20, the muckers can proceed from sector 23 to sector 20 and commence the mucking operation while the drilling crew can proceed from sector go to sector 21 to commence drilling again.

Also the ground support crew, who were previously placing the steel and concrete on the walls of

sectors

21, 22, would advance to

sectors

22, 23 as indicated in FIGURE 6. Thus once again all the operations may be performed simultaneously.

After drilling is completed in section 21, the mucking is finished in sector 20 and the ground support crew is finished in

sector

22, 23, the equipment in the hole is placed to one side and section 21 is blasted. This system will be repeated and the operation will advance as shown in FIGS. 7 and 8 until each crew returns to the starting point. At this point, the hole has increased a depth equal to the height of the face 13 and the whole procedure commences once again and proceeds until the hole is finished.

The timing and coordination of these operations may be varied as desired. *For example, the blasting could be timed so that it would occur at lunch period while the men would be out of the hole or it could occur when the shift was changing. In this way, there will be a minimum of down time while blasting.

Holes may or may not be concrete lined. In some cases, concrete will be poured or sprayed to form a liner and this could also fit into the cycle of operation. For example, in FIGURE 5 the steel may be set in sector 21 while the concrete is set in sector 22.

As the first section 26 of each

sector

20, 21, 22, 23 is blasted, a muck pile left adjacent to the vertical face 13 serves as a barrier to minimize flying rock from the blast.

It will be noted that with the above method, all phases of operation proceed at a continuous downgrade. For example, if the diameter of the hole was 60 feet and the height of the vertical face was 8 feet, the grade at the circumference of the hole at the outer edge would be approximately 4.2%. Thus, the muckers would be digging on a 4.2% grade against a solid bottom. The height of the face 13 is limited by the grade maintained at the bottom of the hole.

The vertical face against which the blasting is done is not necessarily a straight line, but may be modified to any type configuration as illustrated in FIGURE 10. The straight 'face used in the previous description is indicated at 13. However, configurations designated as 30 or 31 may be used as desired.

Also a sump (not shown) may be formed at the center of the hole.

The above described method may be used on any type of earth formation. Although the hole 10 is shown in the shape of a circle, it may be any type configuration.

It is understood that the foregoing description is illustrative of a preferred embodiment of this invention and the scope of the invention is not to be limited thereto, but is to be determined by the appended claims.

I claim:

1. A method of making a hole in a bed of rock by forming the bottom of the hole in the shape of a spiral surface terminating in a generally vertical face, drilling 'a series of blasting bores at the elevated portion of the spiral surface, placing explosives in said blasting bores, detonating said explosives in a predetermined delay sequence such that the explosives adjacent said vertical face are first detonated, removing a portion of the rock loosened by said explosion, and proceeding along a spiral path to form the hole.

2. A method of making a hole in the earth comprising the steps of forming a series of blasting bores in one sector of the hole such that the blasting of said bores will cause to be formed in the bottom of the hole a generally spiral surface, placing explosives in said blasting bores, detonating said explosives, removing a portion of the earth loosened thereby and simultaneously drilling a second series of blasting bores such that the blasting of said second series of bores will cause to be formed in the bottom of the hole a generally spiral surface to form a continuation of said first spiral surface, placing explosives in said second series of blasting bores, detonating said explosives and proceeding in a similar manner along a spiral surface to form the hole.

3. A method of excavating a large vertical hole in the earth of a size sufiiciently large enough to contain a plurality of men and machines which can simultaneously perform drilling and mucking operations in different sectors of the floor of the hole, said method comprising: initially excavating a hole to form a vertical radial wall surface extending substantially radially between the vertical axis and the circumference of the hole and to form a floor extending downwardly spinally about the vertical axis of the hole from the top edge of said vertical radial wall surface to the bottom edge of the vertical radial wall surface; extending said spiral floor deeper by excavating a sector of the upper portion of the spiral floor adjacent said vertical radial wall surface to form a new vertical radial wall surface lying at a different circumferential angle from the first vertical radial wall surface said floor extension step being performed by simultaneously drilling the upper portion of the spiral floor adjacent the vertical radial wall surface and mucking the portion of the hole over the lower portion of the spiral floor adjacent the vertical radial wall surface, thereafter locating explosives in the previously drilled upper portion of the spiral floor and blasting that portion of the 'hole floor, and repeating said simultaneous drilling and mucking operations with the new mucking step being carried out on the previously blasted portion of the floor and the drilling step being carried out on another sector of the upper portion of the spiral floor; and continuing to repeat said floor extension step until the hole reaches the desired depth.

4. The method of claim 3 wherein: the vertical radial Wall surface produced by said steps is an irregular nonuniform surface, as opposed to being a plane surface.

References Cited in the file of this patent UNITED STATES PATENTS 1,202,928 Wallace Oct. 31, 1916 1,833,369 ORourke NOV. 24, 1931 2,591,233 Browne Apr. 1, 1952

Claims

1. A METHOD OF MAKING A HOLE IN A BED OF ROCK BY FORMING THE BOTTOM OF THE HOLE IN THE SHAPE OF A SPIRAL SURFACE TERMINATING IN A GENERALLY VERICAL FACE, DRILLING A SERIES OF BLASTING BORES AT THE ELEVATED PORTION OF THE SPIRAL SURFACE, PLACING EXPLOSIVES IN SAID BLASTING BORES, DETONATING SAID EXPLOSIVE IN A PREDETERMINED DELAY SEQUENCE SUCH THAT THE EXPLOSIVE ADJACENT SAID VERTICAL FACE ARE FIRST DETONATED, REMOVING A PORTION OF THE ROCK LOOSENED BY SAID EXPLOSION, AND PROCEEDING ALONG A SPIRAL PATH TO FORM THE HOLE.