CN104776765A - Static blasting and energy-gathering device and blasting method thereof - Google Patents

Abstract

A static blasting energy-gathering device, the device includes a main body casing composed of two arc-shaped steel formworks, the two arc-shaped steel formworks are not connected, and the midpoint connecting line It is perpendicular to the pre-splitting line; the outside of each arc-shaped steel formwork is provided with a splitting angle, and the tip of the splitting angle is on the same straight line as the pre-splitting line. A method for blasting using a static blasting energy-gathering device, the method comprising the following steps: 1) drilling; 2) placing a static rock-cracking energy-gathering device; 3) pouring rock-cracking agent slurry and waiting for rock-cracking; 4) recycling. The static blasting energy-gathering device and blasting method provided by the present invention can solve the problems of longer crushing time and more crushing amount of medication, speed up the static crushing blasting time, reduce the amount of medication per unit volume of crushing, and improve the crushing efficiency of the static crushing agent.

Description

A static blasting energy-gathering device and blasting method thereof

technical field

The invention relates to the blasting field, in particular to a static blasting energy gathering device and a blasting method thereof.

Background technique

With the development of my country's construction industry and the improvement of living environment requirements, static crushing, as an alternative blasting technology for explosive blasting, has attracted more and more people's attention. The advantages of static blasting are safe and effective, silent crushing, no blasting flying rocks, no dust in blasting, no impact on surrounding buildings, and basically no impact on the surrounding environment. Therefore, it has obvious advantages in concrete demolition, rock and ore mining projects in densely populated urban reconstruction projects, projects with cultural relics to be protected around, and other environmental conditions that are not convenient for explosive blasting. With the acceleration of urbanization in our country, the rapid implementation of old city reconstruction and other projects, static crushing technology will have a good development prospect.

Conventional static blasting is to use the static blasting agent (mainly composed of calcium oxide) installed in the medium drill hole, the calcium oxide turns into calcium hydroxide, and its crystal structure changes, which will cause the expansion of the crystal volume and deform the crystal of the breaking agent. , to generate volume expansion, so that the expansion pressure (up to 30Mpa-50Mpa) is slowly and quietly applied to the hole wall, and reaches the maximum value after a period of time, breaking the medium. This kind of circular drilling makes the expansion force generated by the static breaking agent evenly act on the hole wall, and the small cracks distributed around the hole wall will develop evenly, so that the expansion force cannot be concentrated in the direction to be cracked. Fissures on the fissure line are also difficult to develop quickly.

Static blasting agent is a powdery substance made of special silicate and calcium oxide as the main raw material and other organic and inorganic additives. The typical chemical reaction formula is:

CaO+H ₂ O→Ca(OH) ₂ +6.5×104J

The principle of the crushing medium is to use the calcium oxide installed in the medium borehole to become calcium hydroxide. The change of its crystal structure will cause the expansion of the crystal volume, deform the crystal of the crushing agent, and produce volume expansion, so that the slow, static Statically apply expansion pressure (up to 30Mpa-50Mpa) to the hole wall, and reach the maximum value after a period of time, breaking the medium. According to measurements, under the premise of free expansion, the volume after reaction can increase by 3 to 4 times, and its surface area can also increase by nearly 100 times, and at the same time, 6.5×104J of heat can be released per mole. If it is injected into the blast hole, the expansion is restricted by the hole wall, and the pressure can rise to 50Mpa. Under this pressure, the medium will produce radial compressive stress and tangential tensile stress. This kind of circular drilling makes the expansion force generated by the static breaking agent evenly act on the hole wall, and the small cracks distributed around the hole wall will develop evenly, so that the expansion force cannot be concentrated in the direction to be cracked. Fissures on the fissure line are also difficult to develop quickly.

Although static blasting has many advantages of its own, its limitations are also very obvious. Compared with explosive blasting, its crushing time is longer, the crushing amount per unit volume is more, and it has higher requirements for construction technology and ambient temperature. These problems It also hinders the extensive application of static crushing in engineering.

Contents of the invention

The technical problem to be solved by the present invention is to provide a static blasting energy-gathering device and its blasting method, which can solve the problems of longer crushing time and more medication for crushing, speed up the blasting time for static crushing, reduce the amount of medication per unit volume of crushing, and improve Breaking efficiency of static breakers.

In order to solve the above technical problems, the technical solution adopted in the present invention is: a static blasting energy gathering device,

The device includes a main casing composed of two arc-shaped steel formworks, the two arc-shaped steel formworks are not connected, and the midpoint connecting line of the two-valve arc-shaped steel formwork is perpendicular to the pre-split line; each petal There are splitting angles on the outside of the arc-shaped steel formwork, and the tip of the splitting angle is on the same line as the pre-splitting line;

Both sides of the arc-shaped steel template are respectively provided with a stabilizing shaft guide ring, and a stabilizing shaft is placed on the stabilizing shaft guiding ring.

The main casing is cylindrical.

The included angle a of the tip of the splitting angle is 45 degrees.

The stabilizing shaft guide ring is made up of two concentric circular arc plates, and the centers of the two circular arc plates coincide with the circular centers of the stabilizing shaft.

The central angle b of the stable shaft guide ring is 80 degrees.

A method of blasting using a static blasting energy-gathering device, the method comprising the following steps:

1) Drilling: Drilling holes in rocks that require static blasting;

2) Place the static rock-cracking energy-gathering device: in the drilling hole, first place the main casing of the static rock-cracking energy-gathering device so that the tips of each splitting angle and the pre-cracking line are on the same line, and then insert the four stabilizing shafts into the stabilizing In the shaft guide ring, the placement of the static rock-cracking energy-gathering device is completed;

3) Filling the stone-cracking agent slurry: fill the main casing of the placed energy-gathering device with the stone-cracking agent slurry, and wait for the stone to be cracked;

4) Recycling: After the rock cracking is over, take out the static rock cracking energy-gathering device in the drill hole for the next cycle of rock cracking.

In step 1), the diameter of the drilled hole is 60mm.

A static blasting energy-gathering device and blasting method provided by the present invention have the following beneficial effects:

1. The main casing composed of two arc-shaped steel templates is used. The split angle is set on the arc-shaped steel template. The tip of each split angle is on the same line as the pre-split line. When the expansion force is generated, the arc-shaped steel formwork restricts the expansion force from being dispersed on the rock mass around the hole wall, so that it is concentrated on the steel formwork, and the arc-shaped steel formwork then concentrates the expansion force on the tip of each splitting angle. In this way, stress concentration will be generated at the tip of the splitting angle, so that the rock at the tip of the splitting angle will be split rapidly, while the peak value of strain in other parts of the hole wall will be sharply reduced, and the action time will also be greatly reduced, which can solve the problem. To solve problems such as long crushing time and high crushing dosage, speed up the static crushing blasting time, reduce the crushing dosage per unit volume, and improve the crushing efficiency of the static crushing agent.

2. Unlike conventional static blasting, where the expansion force of the rock-cracking agent acts uniformly on the inner wall of the borehole, the expansion force in the present invention pushes the static blasting energy-gathering device to move to both sides, concentrating the expansion force on the splitting angle, and the rock It is a material whose tensile strength is much lower than the compressive strength, so the concentrated stress at the splitting angle can split the rock quickly.

3. The borehole diameter is designed to be 60mm, which is 1.5 times of the borehole diameter (usually 40mm) in conventional static blasting, which overcomes that in conventional static blasting, if the borehole is too large, it will easily lead to grouting, and if the borehole is small, it needs to be reduced Hole spacing, the disadvantage of increasing the hole density, while increasing the hole diameter, it will not cause spraying, reduce the hole density, and on the other hand, it will also enhance the rock cracking effect.

4. The setting of the stabilizing shaft enables the main casing to be supported on the one hand during the expansion process so that the splitting angle is accurately along the direction of the pre-cracking line; secondly, during the movement of the main casing due to expansion, the rolling of the stabilizing shaft makes The expansion force is concentrated on the splitting angle to the greatest extent, which enhances the stone-cracking effect.

5. The expansion force of the rock blasted by the present invention is mainly concentrated near the splitting angle, and the rock stress at other positions of the borehole wall is very small, so that the maximum possibility of rock splitting from the pre-cracking line is realized, and the decorative rock is greatly improved. Quarry yield.

6. The energy-gathering device for static blasting can be reused, which improves the efficiency of rock cracking and is economical and reliable.

7. The angle a at the tip of the splitting angle is designed to be 45 degrees. On the one hand, it ensures the depth of the splitting angle. At the same time, the large angle ensures that the crack has a certain width after splitting; in addition, the effective stress is greatly increased. Greatly increased the cleaving effect on rocks.

Description of drawings

Below in conjunction with accompanying drawing and embodiment the present invention will be further described:

Fig. 1 is a schematic structural view of a static blasting energy gathering device of the present invention;

Fig. 2 is a large sample diagram of the stable shaft of the static blasting energy gathering device of the present invention;

Fig. 3 is a top view of the static blasting energy gathering device of the present invention;

Fig. 4 is a schematic diagram of placement of a static blasting energy gathering device in the blasting method of the present invention;

Fig. 5 shows the stress on the tip of the splitting angle when there is no splitting angle;

Fig. 6 is when the included angle a of the tip of the splitting angle is 30 degrees, the force situation of the tip of the splitting angle;

Fig. 7 is when the included angle a of the tip of the splitting angle is 45 degrees, the stressed situation of the tip of the splitting angle;

Fig. 8 is when the included angle a of the tip of the splitting angle is 60 degrees, the force situation of the tip of the splitting angle;

Fig. 9 is when the included angle a of the tip of the splitting angle is 90 degrees, the force situation of the tip of the splitting angle;

FIG. 10 is a stress change curve drawn according to Table 1.

Detailed ways

Embodiment one

As shown in Figure 1-Figure 4, a static blasting energy gathering device,

The device includes a main casing 1 composed of two arc-shaped steel formworks 1-1, the two arc-shaped steel formworks 1-1 are not connected, and the midpoint of the two-valve arc-shaped steel formwork 1-1 The connecting line is perpendicular to the pre-splitting line 5; a splitting angle 2 is provided on the outside of each arc-shaped steel formwork 1-1, and the tip 2-1 of the splitting angle 2 is located on the same straight line as the pre-splitting line 5;

Both sides of the arc-shaped steel template 1-1 are respectively provided with a stabilizing shaft guide ring 4, and a stabilizing shaft 3 is placed on the stabilizing shaft guiding ring 4;

The stable shaft 3 has a diameter of 10mm and is made of steel or a stronger alloy material.

The main body casing 1 is a cylinder with an inner diameter of 36mm, an outer diameter of 40mm, and an axial length of 1000mm. The axial length can also be set according to the actual rock cracking depth on site, and it is made of steel or a stronger alloy material.

The angle a at the tip of the splitting angle is 45 degrees, the distance L from the apex of the tip 2-1 to the closest point outside the outer diameter of the main casing 1 is 10mm, and the splitting angle 2 is made of wear-resistant, extrusion-resistant and non-deformable alloy Made of steel material.

The stabilizing shaft guide ring 4 is made up of two concentric arc plates 4-1, and the centers of the two arc plates 4-1 coincide with the centers of the stabilizing shaft 3.

The central angle b of the stabilizing shaft guide ring 4 is 80 degrees, the thickness of the stabilizing shaft guiding ring 4 is 0.5mm, and it is made of high-quality steel. , in order to reduce the frictional force with the stable shaft 3.

Embodiment two

A method of blasting using a static blasting energy-gathering device, the method comprising the following steps:

1) Drilling: Drilling 6 holes on rocks that require static blasting;

2) Place the static rock-cracking energy-gathering device: apply a certain amount of lubricating oil on the guide ring 4 of the stable shaft in advance, and place the main body casing 1 of the static rock-cracking energy-gathering device in the drill hole 6, so that each splitting angle 2 The tip 2-1 and the pre-cracking line 5 are located on the same straight line, and then the four stabilizing shafts 3 are inserted into the stabilizing shaft guide ring 4 to complete the placement of the static rock-cracking energy-gathering device;

3) Filling the rock-cracking agent slurry (the static blasting agent referred to in the background technology): fill the rock-cracking agent slurry in the main casing 1 of the placed energy-gathering device, and wait for the rock-cracking agent;

4) Recycling: After the rock cracking is finished, take out the static rock cracking energy-gathering device in the borehole 6 for the next cycle of rock cracking.

In step 1, the diameter of the drilled hole 6 is 60 mm.

The placement of the static blasting energy gathering device is shown in Figure 4.

Embodiment three

The angle a at the tip of the splitting angle is 45 degrees for the test selection, and the test process is as follows:

The included angle a is designed to be different degrees, when they are 0 degrees, 30 degrees, 45 degrees, 60 degrees and 90 degrees respectively, the large-scale finite element software adina is used to simulate the different force characteristics of the tip of the splitting angle, so as to select the optimal clamping angle horn.

When there is no splitting angle, the stress on the tip of the splitting angle is shown in Figure 5;

When the included angle a of the tip of the splitting angle is 30 degrees, the stress on the tip of the splitting angle is shown in Figure 6;

When the included angle a of the tip of the splitting angle is 45 degrees, the stress on the tip of the splitting angle is shown in Figure 7;

When the included angle a of the tip of the splitting angle is 60 degrees, the stress on the tip of the splitting angle is shown in Figure 8;

When the included angle a of the tip of the splitting angle is 90 degrees, the stress on the tip of the splitting angle is shown in FIG. 9 .

The following table 1 is a table of the stress at the tip of the splitting angle when the included angle a is 0 degrees, 30 degrees, 45 degrees, 60 degrees and 90 degrees respectively.

Table 1

The stress change curve drawn according to Table 1 is shown in Figure 10,

It can be seen from Figure 6-Figure 10 that:

1. When the included angle a is 0 degrees, the effective stress distribution is relatively uniform. During the cracking process, the crack will proceed along the weaker structural surface or other weak parts, and this weak surface cannot be just on the pre-cracking line , so the expansion force cannot be effectively used.

2. When the included angle a is not 0 degrees, the effective stress is mainly concentrated near the splitting angle, while the stress value in other parts is very small, which increases the rock-cracking effect at the tip of the splitting angle 2-1 on the one hand; on the other hand On the one hand, during the quarrying process, the damage to the rock is greatly reduced and the success rate is improved.

3. From the direction of the curve in Figure 10, as the angle a increases, the horizontal stress at the tip gradually decreases, while the vertical stress remains basically unchanged when the angle a is not 0 degrees, and the effective stress It increases with the increase of the angle, but the amount of change is small. In the process of splitting, on the one hand, it is necessary to ensure the depth of the splitting angle, on the other hand, it is necessary to consider the pulling effect of the vertical force, and the The included angle a of the tip is 45 degrees, which ensures the depth of the splitting angle, and at the same time, the large angle ensures that the crack has a certain width after splitting.

4. When the angle a is 0 degrees, the effective stress on the wall of the borehole is 801214Pa, and when the angle a at the tip of the splitting angle is 45°, the effective stress on the wall of the borehole increases to 3400072Pa. It is 4.24 times larger, which greatly increases the splitting effect on rocks.

In summary, the optimal choice of angle a is 45 degrees.

Claims (7)

1. a static blasting energy-gathering device, is characterized in that:

This device comprises spells by two lobe circular arc steel forms (1-1) the main body casing (1) formed, and do not connect between two lobe circular arc steel forms (1-1), the mid point line of two lobe circular arc steel forms (1-1) is vertical with presplitting line (5); Every lobe circular arc steel form (1-1) outside is equipped with splitting angle (2), and tip (2-1) and the presplitting line (5) of splitting angle (2) are located along the same line;

Circular arc steel form (1-1) two edge is respectively provided with stable axis lead ring (4), stable axis lead ring (4) is placed with stable axis (3).

2. static blasting energy-gathering device according to claim 1, is characterized in that: main body casing (1) is cylinder.

3. static blasting energy-gathering device according to claim 1, is characterized in that: the angle a of the tip of splitting angle (2) is 45 degree.

4. static blasting energy-gathering device according to claim 1, is characterized in that: stable axis lead ring (4) is made up of two concentric arc plates (4-1), and the center of circle of two arc plates (4-1) overlaps with the center of circle of stable axis (3).

5. static blasting energy-gathering device according to claim 4, is characterized in that: the central angle b of stable axis lead ring (4) is 80 degree.

6. apply the method that static blasting energy-gathering device carries out explosion, it is characterized in that the method comprises the following steps:

1) hole: on the rock needing static blasting, hole (6);

2) place static state and split stone energy-gathering device: in boring (6), first the static main body casing (1) splitting stone energy-gathering device is placed, the tip (2-1) of each splitting angle (2) and presplitting line (5) are located along the same line, again four stable axis (3) are inserted in stable axis lead ring (4), complete the placement that static state splits stone energy-gathering device;

3) pour into stone cracking agent slurries: in the main body casing (1) of the energy-gathering device placed, fill stone cracking agent slurries, wait for and split stone;

4) reclaim: after splitting stone and terminating, the static state of taking out in boring (6) splits stone energy-gathering device, carries out next circulation and splits stone use.

7. according to claim 6ly a kind ofly apply the method that static blasting energy-gathering device carries out explosion, it is characterized in that: in step 1), the aperture of boring (6) is 60mm.