CN111926873A - Underwater rock cleaning platform with controllable rock drilling rod drilling speed and cleaning method - Google Patents

Abstract

The invention discloses an underwater rock cleaning platform and a cleaning method with a controllable drilling speed of a rock drilling rod. The underwater rock cleaning platform comprises a hull, and a rock drilling control room, a rock drilling rod and a grab bucket are arranged on the deck of the hull. The rock control room is equipped with a boom for controlling the construction position of the rock drill rod and the grab bucket, and a rock drill rod speed control mechanism is installed under the boom, which includes a cantilever and an actuator, and the rear end of the cantilever is fixed on the deck through a turntable. The front end is connected with the actuator; the actuator includes an actuating rod and a servo motor, the axial direction of the actuating rod is the impact direction of the rock drill rod, and the front end of the actuating rod adsorbs the rock drilling rod through electromagnetic, and the servo motor provides the actuating rod with Power, which applies a vertical load to the drill rod, increasing its initial speed. During the rock drilling process, according to the strength of the rock, the water depth and the characteristics of the seabed topography, the cutting speed of the rock drilling rod can be precisely controlled by controlling the lifting height of the rock drilling rod or applying the load of the actuator, so as to reduce the drilling speed under the condition of satisfying the rock drilling requirements. Wear of rock sticks.

Description

A kind of underwater rock cleaning platform and cleaning method with controllable drilling speed of rock drilling rod

technical field

The invention relates to an underwater rock cleaning platform and an underwater rock cleaning method based on the platform, in particular to an underwater rock cleaning platform with a controllable drilling speed of a rock drill rod and an underwater rock cleaning method based on the platform, It belongs to the technical field of marine dredging engineering.

Background technique

Dredging refers to the use of dredgers or other equipment and manual underwater excavation for earthwork to widen and deepen the water area. Reef under construction. Generally speaking, the dredging of soft soil and loose sand should be carried out by raking suction, cutter suction dredger or grab dredger. After the rock formation is broken by the process, the slag is removed with a grab bucket, but the blasting of the reef has a great impact on the surrounding environment, and it is not applicable in the surrounding areas such as dangerous goods or marine ecological protection areas.

At present, the common treatment solution in the industry is to use a grab dredger with a rock drill to break the hard rock layer and then use a grab ship to remove it. Specifically, the rock drill is lifted to a certain height and then falls freely. The gravitational potential energy is converted into a huge impact force to break the rock. However, this method has poor applicability in shallow water and offshore areas. It is limited to the lifting height of the rock drilling platform and the gravitational potential energy of the rock drilling rod is small, so it cannot provide a high impact speed when drilling rocks, and cannot achieve a good impact speed. Rock breaking effect.

SUMMARY OF THE INVENTION

Purpose of the invention: Aiming at the problem that the existing rock drilling rod breaking and reef cleaning method cannot provide a high impact speed and is not suitable for rock cleaning in shallow water areas, the present invention provides an underwater rock cleaning with a controllable rock drilling rod cutting speed A platform is provided, and an underwater rock cleaning method based on the platform is provided.

Technical solution: An underwater rock cleaning platform with a controllable rock drilling rod cutting speed according to the present invention includes a hull that can travel to a reef-clearing area, and a rock drilling device is provided on the deck of the hull, and the rock drilling device includes a rock drilling device. Rock control room, boom, rock drill rod, grab bucket and rock drill rod speed control mechanism, one end of the boom is movably connected with the rock drill control room, and the other end is connected with rock drill rod or grab bucket to control its construction position; rock drill rod The speed control mechanism is located under the boom, including a horizontally arranged boom and an actuator, the rear end of the boom is fixed on the deck through a turntable, and can rotate around the turntable, and the front end of the boom is connected with the actuator, and the actuator can move along the boom The front end moves horizontally; the actuator includes an actuating rod and a servo motor, wherein the axial direction of the actuating rod is the impact direction of the rock drill rod, and the front end of the actuating rod adsorbs the rock drilling rod through electromagnetic, and the servo motor provides power for the actuating rod , apply a vertical load to the rock drill rod and increase the initial speed of the rock drill rod.

Preferably, the boom includes two connecting ends, the first end is hinged with the rock drilling control room, and the second end is suspended by a cable for a rock drilling rod or a grab; the rock drilling device further includes a traction device, the traction device and the boom are connected to each other. The second end is connected to adjust the lifting angle of the boom and control the operable range of the boom; the traction device is also connected to the cable for suspending the rock drill rod or the grab bucket, and is used for pulling the rock drill rod or the grab bucket. lift.

Preferably, the bottom of the rock drilling control room is fixedly connected to the deck through a turntable, the turntable rotates, and the boom rotates with the rock drilling control room to control the drilling position and cleaning position of the rock drilling rod and the grab.

The underwater rock cleaning method based on the above-mentioned underwater rock cleaning platform of the present invention comprises the following steps:

(1) Obtain seabed rock samples in the construction area, and measure the uniaxial compressive strength of the rock;

(2) According to the uniaxial compressive strength of the rock, calculate the impact velocity of the rock drill rod required for the rock impact crushing;

(3) Establish three-dimensional topographical graphics of the construction area, and calculate the water depth of the construction area;

(4) Determine whether the kinetic energy required for rock breaking can be provided by the rock drill rod alone. If so, calculate the lifting height of the rock drill rod according to the impact speed; otherwise, calculate the load that the actuator needs to apply to the rock drill rod according to the impact speed. ;

(5) Determine other parameters of rock drilling construction according to the three-dimensional landform graphics and the calculation result of step (4);

(6) Install rock drilling rods to carry out rock drilling operations in the target area; after the rock is impacted and broken, install a grab bucket to clean up the broken rock;

(7) Re-establish the three-dimensional topography of the construction area, and drill again for the areas that do not reach the design elevation until all areas reach the design elevation.

In the above-mentioned step (2), the impact velocity v' of the rock drilling rod required for rock impact crushing can be calculated according to the following formula:

In the formula: F is the minimum pressure required for rock crushing, m is the mass of the rock drilling rod, t is the contact time between the rock drilling rod and the rock during impact crushing; P is the uniaxial compressive strength of the rock, and S is the rock drilling rod The area of the tip of the stick.

Specifically, in step (4), the method for judging whether the kinetic energy required for rock fragmentation can be provided by the rock drill rod alone is: when the impact pressure of the rock drill rod when drilling the rock is greater than or equal to the kinetic energy required for rock fragmentation, it means that the rock The kinetic energy required for breaking can be provided by the rock drill rod alone; on the contrary, the actuator needs to apply a load to the rock drill rod to increase the water entry speed of the rock drill rod; wherein, the impact pressure of the rock drill rod when it hits the rock is the rock drill rod gravity The difference between the potential energy and the work done by the buoyancy of the rock drill rod in free fall in the construction area.

When the impact pressure of the rock drill rod is greater than or equal to the pressure required for rock breaking, the lifting height h of the rock drill rod can be calculated according to the following formula:

where m is the mass of the rock drill rod, g is the gravitational acceleration _of the construction area; ρ is the density of the water in the construction area, and v' is the impact velocity of the rock drill rod.

When the impact pressure of the rock drilling rod is less than the pressure required for rock breaking, the load F ₁ that the actuator needs to apply to the rock drilling rod can be calculated according to the following formula:

In the formula: S is the working length of the actuator, m is the mass of the rock drill rod, g is the gravitational acceleration of the construction area, h ₁ is the falling height of the rock drill rod in the atmosphere, h ₂ is the water depth of the construction area; ρ _liquid is The density of water in the construction area, v _row is the volume of water displaced by the rock drill rod, and v' is the impact velocity of the rock drill rod.

Preferably, in steps (3) and (7), the three-dimensional topographical graph of the construction area may be established by performing multi-beam bathymetry on the rock drilling area. In step (5), other parameters of the rock drilling construction may include the number of times of gouging of the rock drilling points and the row distance and position distance between the rock drilling points.

Beneficial effects: Compared with the prior art, the advantages of the present invention are: (1) An actuator is added to the underwater rock cleaning platform of the present invention, and the actuator can apply a vertical load to the rock drilling rod, so as to improve the drilling efficiency. (2) The underwater rock cleaning method of the present invention has the characteristics of convenient operation and simple construction. During the rock drilling process, the strength, water depth and Seabed landform features, by controlling the lifting height of the rock drilling rod or the applied load of the actuator, the drilling speed of the rock drilling rod can be accurately controlled, and the wear of the rock drilling rod can be reduced under the condition of meeting the rock drilling requirements, making it more efficient and efficient. environmental requirements.

Description of drawings

Fig. 1 is the schematic diagram that adopts the underwater rock cleaning platform of the present invention to carry out rock drilling construction in deep water area;

Fig. 2 is the schematic diagram that adopts the underwater rock cleaning platform of the present invention to carry out rock drilling construction in shallow water area;

Fig. 3 is the enlarged view of A part in Fig. 2;

FIG. 4 is a flow chart of the rock cleaning method of the present invention.

Detailed ways

The technical solutions of the present invention will be further described below with reference to the accompanying drawings and embodiments.

The invention provides an underwater rock cleaning platform with a controllable rock drilling rod chisel speed, which improves the existing rock drilling ships commonly used in the underwater heavy hammer impact rock drilling method, so that it can be applied to shallow water areas at the same time. The shallow water area achieves better rock breaking effect.

As shown in Figures 1-3, the underwater rock cleaning platform includes a hull 1, which can travel to a specific construction area, and a rock drilling device and a living area 9 are arranged on the hull deck 2. The rock drilling device includes a rock drilling control room 8 , a turntable 3 , a boom 4 , a rock drilling rod 5 , a grab bucket 6 and a rock drilling rod speed control mechanism.

The rock drilling control room 8 is arranged on one side of the hull 1 and is connected to the boom 4 , and the rock drilling process is controlled by controlling the movement of the boom 4 . The boom 4 includes two connecting ends, the first end is hinged with the rock drilling control room 8, and the second end is provided with a cable, which can hang the rock drilling rod 5 or the grab 6; when the rock drilling and breaking are required, the bottom of the cable is Hang the rock drill rod 5 and place the grab bucket 6 on the deck 2. After the crushing is completed, remove the rock drill rod 5 and hang the grab bucket 6 to clean up the broken reef. The second end of the boom 3 is also connected to the traction device 14, and the traction device 14 can pull the second end of the boom 4 through the traction cable to adjust its lifting angle, control the operable range of the boom 4, and then control the rock drill rod 5 or the gripper. The distance between the bucket 6 and the hull is far and near; the pulling device 14 may also include a second pulling cable, which is connected with the cable on the boom to pull the rock drill rod 5 or the grab bucket 6 up and down.

The bottom of the rock drilling control room 8 is fixedly connected to the deck 2 through the turntable 3, the turntable 3 rotates, the rock drilling control room 8 rotates, and the boom 4 connected to it drives the rock drilling rod 5 and the grab 6 to rotate, changing the drilling or cleaning position.

For convenience of description, the front end and rear end mentioned in this specification are relative to the rock drill rod, wherein the end close to the rock drill rod is called the front end, and the end far from the rock drill rod is called the rear end. The rock drilling rod speed control mechanism is located below the boom 4 and includes a horizontally arranged boom 10 and an actuator. The front end of the cantilever 10 is connected with the actuator, and the actuator can generate horizontal displacement along the front end of the cantilever 10 . The actuator is a servo actuator, which includes an actuating rod 15 and a servo motor 11 , and the axial direction of the actuating rod 15 is the impact direction of the rock rod. The front end of the actuating rod 15 can be provided with an electromagnetic adsorption member 16, which is connected to the rock drilling rod 5 by electromagnetic suction; The servo motor 11 provides power for the actuating rod 15. For example, the hydraulic pressure can be controlled by the servo, and a vertical load can be applied to the rock drilling rod 5 through the actuating rod 15 to overcome the electromagnetic suction of the actuator, so as to increase the initial speed of the rock drilling rod and increase the The falling speed of the rock drill rod increases its impact strength. Figure 3 shows the connection state diagram of the front end of the actuating rod 15, the electromagnetic adsorption member 16 and the rock drill rod 5 after the vertical load is applied, where S is the load applied by the actuator working length. The rear end of the cantilever 10 can be fixed on the deck 2 through a turntable 12, and the turntable 12 can be a rotating shaft, so that the cantilever 10 can rotate around the turntable 12, and drive the actuator to change positions.

The underwater rock cleaning method based on the underwater rock cleaning platform, as shown in Figure 4, may specifically include the following steps:

Step 1: Overhaul the construction equipment of the underwater rock cleaning platform, and the construction ships such as mud barges, anchor boats, and guard ships enter the site to prepare for the rock drilling construction;

Step 2, obtain seabed rock samples in the construction area, and measure the uniaxial compressive strength of the rock;

Step 3, according to the uniaxial compressive strength of the rock, calculate the impact velocity of the rock drill rod required for the rock impact and fracture;

The impact velocity v' of the rock drill rod required for rock impact crushing can be calculated according to the following formula:

Strength calculation formula:

The law of conservation of momentum: Ft=mv

Therefore, the minimum pressure F=PS required for rock crushing, and the chisel speed required for rock crushing is

In the formula: F is the minimum pressure required for rock crushing, m is the mass of the rock drilling rod, t is the contact time between the rock drilling rod and the rock during impact crushing; P is the uniaxial compressive strength of the rock, and S is the rock drilling rod The area of the tip of the stick.

Step 4, carry out multi-beam water depth measurement on the rock drilling area, establish a three-dimensional topographic map of the construction area, and calculate the water depth of the construction area;

Step 5: Determine whether the kinetic energy required for rock breaking can be provided by the rock drill rod alone. If so, calculate the lifting height of the rock drill rod according to the impact speed; otherwise, calculate the load that the actuator needs to apply to the rock drill rod according to the impact speed. ;

When the impact pressure of the rock drilling rod is greater than or equal to the kinetic energy required for rock breaking, it means that the kinetic energy required for rock breaking can be provided by the rock drilling rod alone; The water entry speed of the rock rod; among them, the impact pressure of the rock drill rod when it hits the rock is the difference between the rock drill rod's gravitational potential energy and the buoyancy work of the rock drill rod falling freely in the construction area.

(1) If the water depth of the rock drilling area is large, by controlling the lifting height of the rock drill rod, the gravity potential energy of the rock drill rod free fall is converted into kinetic energy, and the impact pressure of the rock drill rod when it hits the rock is greater than or equal to the pressure required for the rock to break. , the actuator does not need to apply a load to the rock drill rod, and the lifting height h of the rock drill rod is calculated by the following method:

The law of conservation of momentum:

Buoyancy calculation formula: F _float = ρ _liquid gv _row

In water, the rock drilling rod is accelerated downward by the action of gravity G and _buoyancy F, so the lifting height h of the rock drilling rod can be calculated by the following formula:

where m is the mass of the rock drill rod, g is the gravitational acceleration _of the construction area; ρ is the density of the water in the construction area, and v' is the impact velocity of the rock drill rod.

(2) If the water depth in the rock drilling area is shallow, by controlling the lifting height of the rock drill rod, the gravity potential energy of the free fall of the rock drill rod is converted into kinetic energy. The actuator needs to apply a load to the rock drill rod to increase the water entry speed of the rock drill rod. The following method is used to calculate the applied load of the actuator:

Newton's second law: F=ma

Velocity formula: v=v ₀ +at

Displacement formula:

凿岩棒脱离作动器在大气中下降时，受重力G的作用向下自由落体加速，入水后又受到向上的浮力F_浮的影响，根据动量守恒定律，运用下式可以计算出作动器施加载荷F₁：According to Newton's second law, the velocity formula and the displacement formula, the velocity when the rock drill rod is disengaged from the actuator can be calculated

When the rock drilling rod is separated from the actuator and descends in the atmosphere, it is accelerated by gravity G in a downward free fall, and is affected by the upward _buoyancy F after entering the water. According to the law of conservation of momentum, the actuator can be calculated by the following formula Apply load F ₁ :

In the formula: S is the working length of the actuator, m is the mass of the rock drill rod, g is the gravitational acceleration of the construction area, h ₁ is the falling height of the rock drill rod in the atmosphere, h ₂ is the water depth of the construction area; ρ _liquid is The density of water in the construction area, v _row is the volume of water displaced by the rock drill rod, and v' is the impact velocity of the rock drill rod.

Step 6, according to the three-dimensional topographic graph and the calculation result of step 5, determine other parameters of the rock drilling construction, such as the number of times of the rock drilling points and the row spacing and position distance between the rock drilling points;

Step 7, install the rock drilling rod 5 under the cable 7 of the boom 4, and use the actuator to apply the required load to the rock drilling rod 5 according to the calculation result of step 5, and carry out the rock drilling operation in the target area; after the rock is impacted and broken, Install the grab bucket 6 to clean up the broken rocks;

Step 8: Perform multi-beam bathymetry again to establish a three-dimensional geomorphological graph of the construction area, and drill again for areas that do not reach the design elevation until all areas reach the design elevation.

Example 1

Taking the rock drilling construction in a certain deep water area as an example, the underwater cleaning method of the present invention will be described.

The schematic diagram of rock drilling construction in this deep water area is shown in Figure 1. Among them, the mass of the rock drill rod used is m=35000kg, the area of the rock drill rod tip S=0.039m ² , the acceleration of gravity g=9.81m/s ² , the density of water ρ _liquid =1.0×10 ³ kg/m ^3. The density of iron ρ _Fe = 7.8×10 ³ kg/m ³ , the contact time between the rock drilling rod and the rock t = 0.2s, the uniaxial compressive strength of the rock in the drilling area σ ₁ = 87.3MPa, the water depth in the drilling area h ₂ =35m.

计算可得岩石破碎所需的最小压力F＝PS＝3404.7KN，岩石破碎所需的最小速度为

According to the strength calculation formula

Calculate the minimum pressure F=PS=3404.7KN required for rock crushing, and the minimum speed required for rock crushing is

此时

故作动器不需要为凿岩棒施加载荷，运用如下公式计算出凿岩棒的提升高度h：Since the gravitational potential energy of the rock drill rod E _P =mgh ₂ =12017.25KJ, the buoyancy work of the rock drill rod W _{F float} = ρ _liquid gv _discharge h = 1540.67KJ, the kinetic energy required for rock breaking

at this time

Therefore, the actuator does not need to apply load to the rock drill rod, and the following formula is used to calculate the lifting height h of the rock drill rod:

where:

m: mass of rock drill rod, (kg); g: gravity acceleration of the place, (m/s ² ); h: lifting height of rock drill rod, (m); ρ _liquid : density of water, (kg/m ³ ); v': the gouging speed of the rock drill rod, (m/s).

The lifting height h=22.11m of the rock drilling rod is obtained.

Determine the parameters of rock drilling construction, specifically, the lifting height of the rock drilling rod is 22.11m, the number of times of drilling the rock drilling point is 2 times, the row spacing of the rock drilling point is 2.5m, and the rock drilling point spacing is 1.7m.

A rock drilling rod 5 is installed under the cable 7 of the boom 4, and the cable is lowered to a height of 22.11m from the rock surface, and the rock drilling operation in the target area is carried out; after the rock is impacted and broken, a grab bucket 6 is installed to clean the broken rock;

Perform multi-beam bathymetry again to establish a three-dimensional topographic map of the construction area, and drill again for areas that do not reach the design elevation until all areas reach the design elevation.

Example 2

Taking the rock drilling construction in a shallow water area as an example, the underwater cleaning method of the present invention will be described.

The schematic diagram of rock drilling construction in this shallow water area is shown in Figure 2. Among them, the mass of the rock drill rod used is m=35000kg, the area of the rock drill rod tip S=0.039m ² , the working length of the actuator S=0.3m, the acceleration of gravity g=9.81m/s ² , the water Density ρ _liquid =1.0×10 ³ kg/m ³ , density of iron ρ _iron =7.8×10 ³ kg/m ³ , contact time t=0.2s of rock drill rod and rock, uniaxial compression resistance of rock in rock drilling area The strength σ ₁ =87.3MPa, the falling height of the rock drilling rod in the atmosphere h ₁ =3m, and the water depth of the rock drilling area h ₂ =10m.

计算可得岩石破碎所需的最小压力F＝PS＝3404.7KN，岩石破碎所需的最小速度为

According to the strength calculation formula

Calculate the minimum pressure F=PS=3404.7KN required for rock crushing, and the minimum speed required for rock crushing is

此时

故作动器需要为凿岩棒施加载荷，运用如下公式计算出作动器的施加载荷F₁：Since the gravitational potential energy of the rock drill rod E _P =mgh ₂ =3433.5KJ, the buoyancy work of the rock drill rod W _{F float} = ρ _liquid gv _row h = 440.19KJ, the kinetic energy required for rock breaking

at this time

Therefore, the actuator needs to apply a load to the rock drill rod, and the applied load F ₁ of the actuator is calculated by the following formula:

where:

F ₁ : The applied load of the actuator, (KN); S: The working length of the actuator, (m); m: The mass of the rock drilling rod, (kg); g: The acceleration of gravity at the place, (m/s ² ); h ₁ : the falling height of the rock drilling rod in the atmosphere, (m); h ₂ : the water depth of the rock drilling area, (m); ρ _liquid : the density of water, (kg/m ³ ); v _row : chisel The volume of water displaced by the rock rod, (m ³ ); v': the gouging speed of the rock rod, (m/s).

Obtain the applied load F ₁ =8656.43KN that should be applied by the actuator.

The parameters of rock drilling construction are determined, specifically, the load applied by the actuator is 8656.43KN, the number of rock drilling is 2 times, the row spacing of rock drilling points is 2.5m, and the rock drilling point spacing is 1.7m.

A rock drilling rod 5 is installed under the cable 7 of the boom 4, and the rock drilling rod is connected to the actuator. The actuator applies a load of 8656.43KN to carry out the rock drilling operation in the target area; after the rock is impacted and broken, install the grab bucket 6 to clean it up. broken rock;

Perform multi-beam bathymetry again to establish a three-dimensional topographic map of the construction area, and drill again for areas that do not reach the design elevation until all areas reach the design elevation.

Claims (10)

1. a controllable underwater rock cleaning platform with a rock drilling rod chising speed, is characterized in that, comprises the hull that can travel to the reef clearing area, is provided with rock drilling device on the hull deck, and this rock drilling device comprises rock drilling control chamber, boom, rock drilling rod, grab bucket and rock drilling rod speed control mechanism, one end of the boom is movably connected with the rock drilling control room, and the other end is connected with a rock drilling rod or a grab bucket to control its construction position; The rock bar speed control mechanism is located under the boom, including a horizontally arranged boom and an actuator, the rear end of the boom is fixed on the deck through a turntable, and can rotate around the turntable, and the front end of the boom is connected with the actuator, and the actuator can It moves horizontally along the front end of the cantilever; the actuator includes an actuating rod and a servo motor, wherein the axial direction of the actuating rod is the impact direction of the rock drilling rod, and the front end of the actuating rod absorbs the rock drilling rod through electromagnetic adsorption, and the servo motor is used as the actuation rod. The moving rod provides power, applies a vertical load to the rock drill rod, and increases the initial speed of the rock drill rod. 2 . The underwater rock cleaning platform with controllable rock drilling speed according to claim 1 , wherein the boom comprises two connecting ends, the first end is hinged with the rock drilling control room, and the second end is hinged. 3 . The rock drilling rod or the grab bucket is suspended by a cable; the rock drilling device further includes a traction device, which is connected with the second end of the boom for adjusting the lifting angle of the boom and controlling the operable range of the boom; The traction device is also connected with a cable for suspending the rock drill rod or the grab bucket, and is used for pulling the rock drill rod or the grab bucket up and down. 3. The underwater rock cleaning platform with controllable rock drilling speed according to claim 1, wherein the bottom of the rock drilling control room is fixedly connected to the deck through a turntable, the turntable rotates, and the boom follows the rock drilling. The control room rotates to control the chisel position and cleaning position of the rock drill rod and grab bucket. 4. the underwater rock cleaning method based on the described underwater rock cleaning platform of claim 1, is characterized in that, comprises the steps: (1) Obtain seabed rock samples in the construction area, and measure the uniaxial compressive strength of the rock; (2) According to the uniaxial compressive strength of the rock, calculate the impact velocity of the rock drill rod required for the rock impact crushing; (3) Establish three-dimensional topographical graphics of the construction area, and calculate the water depth of the construction area; (4) Determine whether the kinetic energy required for rock breaking can be provided by the rock drill rod alone. If so, calculate the lifting height of the rock drill rod according to the impact speed; otherwise, calculate the load that the actuator needs to apply to the rock drill rod according to the impact speed. ; (5) Determine other parameters of rock drilling construction according to the three-dimensional landform graphics and the calculation result of step (4); (6) Install rock drilling rods to carry out rock drilling operations in the target area; after the rock is impacted and broken, install a grab bucket to clean up the broken rock; (7) Re-establish the three-dimensional topography of the construction area, and drill again for the areas that do not reach the design elevation until all areas reach the design elevation. 5. underwater rock cleaning method according to claim 4 is characterized in that, in step (2), according to the following formula, the impact velocity v' of rock drilling rod required for rock impact crushing is calculated:

F = PS; In the formula: F is the minimum pressure required for rock crushing, m is the mass of the rock drilling rod, t is the contact time between the rock drilling rod and the rock during impact crushing; P is the uniaxial compressive strength of the rock, and S is the rock drilling rod The area of the tip of the stick. 6. The method for cleaning underwater rocks according to claim 4, wherein in step (4), the method for judging whether the kinetic energy required for rock fragmentation can be provided by the rock drill rod alone is: when the rock drill rod drills When the impact pressure when hitting the rock is greater than or equal to the kinetic energy required for rock breaking, it means that the kinetic energy required for rock breaking can be provided by the rock drill rod alone; on the contrary, the actuator needs to apply a load to the rock drill rod to increase the water entry speed of the rock drill rod ; Wherein, the impact pressure of the rock drilling rod when it hits the rock is the difference between the gravitational potential energy of the rock drilling rod and the buoyancy work of the rock drilling rod falling freely in the construction area. 7. underwater rock cleaning method according to claim 6 is characterized in that, in step (4), when the impact pressure when the rock drill rod is chiseling the rock is greater than or equal to the pressure required for rock breakage, calculate according to the following formula Lifting height h of the drill rod:

where m is the mass of the rock drill rod, g is the gravitational acceleration _of the construction area; ρ is the density of the water in the construction area, and v' is the impact velocity of the rock drill rod. 8. underwater rock cleaning method according to claim 6 is characterized in that, in step (4), when the impact pressure when the rock drill rod is chiseling the rock is less than the pressure required for rock breaking, calculate according to the following formula The load F ₁ that the actuator needs to apply to the rock drill rod:

In the formula: S is the working length of the actuator, m is the mass of the rock drill rod, g is the gravitational acceleration of the construction area, h ₁ is the falling height of the rock drill rod in the atmosphere, h ₂ is the water depth of the construction area; ρ _liquid is The density of water in the construction area, v _row is the volume of water displaced by the rock drill rod, and v' is the impact velocity of the rock drill rod. 9 . The method for cleaning underwater rocks according to claim 4 , wherein, in steps (3) and (7), a three-dimensional topographic figure of the construction area is established by performing multi-beam bathymetry on the rock drilling area. 10 . 10. The underwater rock cleaning method according to claim 4, characterized in that, in step (5), other parameters of the rock drilling construction include the number of times of the rock drilling points and the row spacing between the rock drilling points and spacing.

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