The safety issue of pipe pile foundation construction has always been a prominent weak link in the entire construction. Personal casualties and equipment safety accidents account for a large proportion of safety accidents in the construction industry. One of its main characteristics is personal casualties and equipment accidents. At the same time, the cause of personal injury and death accidents is often equipment accidents.
(2) Diesel hammer pile driver: It uses fuel explosion to push the piston, and uses the explosive force to impact the pile head, causing the pile to sink into the ground. It is suitable for driving all kinds of prefabricated piles.
(3) Vibration hammering machine: Use the mechanical vibration force of the pile hammer to sink the piles into the soil. It is suitable for precast concrete pile plates, steel sheet piles, etc. with small load capacity.
(4) Static pile driver: Uses the pressure generated by a mechanical winch or hydraulic system to press the piles into the soil under the action of continuous static pressure. It is suitable for various types of prefabricated piles with general bearing capacity.
(2) Long spiral drill: The motor rotates through the reduction box to rotate the long spiral drill rod, causing the soil to rise to the surface along the spiral blades and discharge out of the hole. It is suitable for clay layer areas with low groundwater levels and small pile hole diameters. building foundation.
(3) Rotary drilling rig: The motor rotates to drive the short spiral drill rod and the soil box to rotate. When the soil in the soil box is full, the soil box is lifted out of the surface and soil is taken, and the cycle repeats.
(4) Submersible drilling machine: The motor and drill bit are structurally connected together, and the motor can dive to the bottom of the hole with the drill bit during operation.
1. The pile frame is the basic equipment used in conjunction with the special working equipment for piling. It is commonly known as the main machine. Its main function is to bear the weight of the working equipment, piles and other machines. It is also responsible for lifting piles, lifting pile conveyors, lifting hoppers, etc., and can walk and When the pile frame is rotated and matched with a diesel hammer, it is a diesel pile driver. When the pile frame is matched with a vibrating pile hammer, it is a vibrating sinking and pulling pile driver.
2. There are various forms of pile frames. No matter what type of pile frame, its structure mainly consists of chassis, guide rod, rear diagonal brace, power unit, transmission mechanism, braking mechanism, walking and slewing mechanism, etc.The pile frame is mainly made of steel. According to the different walking methods, it is divided into crawler type, rolling type, boat-carrying walking type, track type, etc. The height of the pile frame can be assembled in sections according to actual work needs, and the total length of each section is 4~ 6m.
Pile frame height = pile length + working device height + accessory height + safety distance + working allowance. For example: the pile length is 18m, the hammer height is 5m, the pile cap is 1m, the safety distance is 1m, and the working margin is 0.5m, then the effective height of the pile frame = 18+5+1+1+0.5=25.5m.
The diesel pile driving hammer is a special impact equipment for driving prefabricated piles. It is matched with the pile frame to form a diesel pile driver. It uses diesel as fuel, and from a structural point of view, it is actually a large single-cylinder two-stroke internal combustion engine.
The impact body of the diesel hammer is a piston or cylinder liner. It has the characteristics of simple structure, high construction efficiency, wide adaptability, and wide application range. However, with the strengthening of people's environmental awareness and the increase in the density of urban buildings, the shortcomings of diesel piling hammers, such as loud noise, serious exhaust gas pollution, large vibration, and destructive effects on surrounding buildings, have emerged. Therefore, this machine is not suitable for pile foundations in urban areas. Use in construction is subject to certain restrictions.
(2) During the pile driving process, there should be a dedicated person responsible for pulling the control rope on the crank arm so that the hammer can be stopped urgently in case of an unexpected situation.
(3) The take-off height of the upper piston shall not exceed 2.5m.
(4) During the piling process, the piling frame should be checked frequently with a line hammer and level. If the verticality deviation exceeds 1%, it must be corrected in time to avoid driving the pile at an angle.
(5) During the piling process, no one is allowed to enter within a 4m radius centered on the pile axis.
(2) After the pile is inserted into the pile clamper, move the control lever to the clamping position and let the pile clamper slowly clamp the pile until the sound of oil pressure unloading is heard. During the entire operation, the joystick should always be placed in the clamping position, and the hydraulic system pressure cannot drop.
(3) For cranes that suspend pile hammers, the hook must have a safety device.
(4) When pulling out steel sheet piles, they should be pulled out in the opposite direction to the usual sinking sequence. When clamping the sheet pile, the holder should be as close as possible to the adjacent one to make it easier to pull out.
(5) After the pile clamping device clamps the pile, the pressure gauge must wait until the pressure reaches the rated value before commanding to pull it out. When the pile is pulled out 1~1.5m from the ground, the vibration should be stopped, the hanging pile should be tied with a wire rope, and then the pile hammer should be started to pull out the pile.
(6) When pulling out piles, attention must be paid to the rated lifting capacity of the crane. The estimation method is usually used, that is, the radius of gyration of the crane should be determined by the ratio of 1m to 1t of pile length.
(7) After the pile is completely pulled out, the pile clamp must not be loosened before the pile lifting wire rope is tightened.
(1) During the pile driving construction, the pile position should be inserted correctly. If there are underground obstacles that cause the pile to tilt during the driving process, the pile driver cannot be used to forcefully correct the deviation. The pile should be pulled up and reinstalled after the underground obstacles are removed. Instrumentation.
(2) When the clamping mechanism and the pile side slip during the pile pressing process, the hydraulic oil pressure cannot be increased arbitrarily and the operation is forced. Instead, the cause of the slippage should be found out and effective measures must be taken before the pile pressing can continue.
(3) When the pile penetration resistance is too large and the pile cannot be pressed to the elevation, the counterweight cannot be increased arbitrarily, otherwise it will cause damage to the hydraulic components and components.
(4) When the top of the pile cannot be pressed to the designed elevation, the pile must be chiseled away. It is strictly forbidden to use a pile driver to drive the pile up.
(5) During the pile pressing process, if the surrounding soil bulges and affects the movement of the pile driver, the bulging soil in front of the pile driver should be shoveled away and should not be forced through to avoid damage to the pile driver components.
(6) During the jacking process of the pile driver, try to avoid any ship-shaped track pressing on the top of a single pile that has been embedded in the soil, otherwise the ship-shaped track will be deformed.
(7) The electrical system of the pile driver must be effectively grounded. During construction, the cables must be cared for by dedicated personnel, and the main power switch must be turned off at the end of each day.
The scope of application of piling machinery and its advantages and disadvantages
1. Prefabricated pile construction machinery
(1) Steam hammer pile driver: It uses high-pressure steam to lift the hammer head, and then uses the weight of the hammer head to impact the pile head downwards, causing the pile to sink into the ground.(2) Diesel hammer pile driver: It uses fuel explosion to push the piston, and uses the explosive force to impact the pile head, causing the pile to sink into the ground. It is suitable for driving all kinds of prefabricated piles.
(3) Vibration hammering machine: Use the mechanical vibration force of the pile hammer to sink the piles into the soil. It is suitable for precast concrete pile plates, steel sheet piles, etc. with small load capacity.
(4) Static pile driver: Uses the pressure generated by a mechanical winch or hydraulic system to press the piles into the soil under the action of continuous static pressure. It is suitable for various types of prefabricated piles with general bearing capacity.
2. Cast-in-place pile construction machinery
(1) Rotary drilling machine: It uses mechanical transmission to rotate the grinding disc parallel to the ground. Through the drill pipe, it drives the drill bit to rotate and cut the soil and rock layers. It uses water as the medium to take the rock and soil out of the ground. It is suitable for all kinds of medium-sized drilling machines. diameter cast-in-place piles.(2) Long spiral drill: The motor rotates through the reduction box to rotate the long spiral drill rod, causing the soil to rise to the surface along the spiral blades and discharge out of the hole. It is suitable for clay layer areas with low groundwater levels and small pile hole diameters. building foundation.
(3) Rotary drilling rig: The motor rotates to drive the short spiral drill rod and the soil box to rotate. When the soil in the soil box is full, the soil box is lifted out of the surface and soil is taken, and the cycle repeats.
(4) Submersible drilling machine: The motor and drill bit are structurally connected together, and the motor can dive to the bottom of the hole with the drill bit during operation.
Pile frame
1. The pile frame is the basic equipment used in conjunction with the special working equipment for piling. It is commonly known as the main machine. Its main function is to bear the weight of the working equipment, piles and other machines. It is also responsible for lifting piles, lifting pile conveyors, lifting hoppers, etc., and can walk and When the pile frame is rotated and matched with a diesel hammer, it is a diesel pile driver. When the pile frame is matched with a vibrating pile hammer, it is a vibrating sinking and pulling pile driver.2. There are various forms of pile frames. No matter what type of pile frame, its structure mainly consists of chassis, guide rod, rear diagonal brace, power unit, transmission mechanism, braking mechanism, walking and slewing mechanism, etc.The pile frame is mainly made of steel. According to the different walking methods, it is divided into crawler type, rolling type, boat-carrying walking type, track type, etc. The height of the pile frame can be assembled in sections according to actual work needs, and the total length of each section is 4~ 6m.
Pile frame height = pile length + working device height + accessory height + safety distance + working allowance. For example: the pile length is 18m, the hammer height is 5m, the pile cap is 1m, the safety distance is 1m, and the working margin is 0.5m, then the effective height of the pile frame = 18+5+1+1+0.5=25.5m.
Diesel pile driving hammer
The diesel pile driving hammer is a special impact equipment for driving prefabricated piles. It is matched with the pile frame to form a diesel pile driver. It uses diesel as fuel, and from a structural point of view, it is actually a large single-cylinder two-stroke internal combustion engine.The impact body of the diesel hammer is a piston or cylinder liner. It has the characteristics of simple structure, high construction efficiency, wide adaptability, and wide application range. However, with the strengthening of people's environmental awareness and the increase in the density of urban buildings, the shortcomings of diesel piling hammers, such as loud noise, serious exhaust gas pollution, large vibration, and destructive effects on surrounding buildings, have emerged. Therefore, this machine is not suitable for pile foundations in urban areas. Use in construction is subject to certain restrictions.
1. Structure of guide rod diesel hammer
Guide rod diesel hammer consists of piston, cylinder hammer, guide rod, top beam, landing gear, fuel system and base.2. Structure of simple diesel hammer
The simple diesel hammer relies on the up and down movement of the piston to hammer piles, and is composed of a hammer body, a fuel supply system, a lubrication system, a cooling system and a starting system.3. Key points for safe operation of diesel hammer
(1) The pile frame must be placed stably and solidly. When starting the pile hammer, attention should be paid to the fact that the pile hammer and pile cap are in the same straight line to prevent eccentric pile driving.(2) During the pile driving process, there should be a dedicated person responsible for pulling the control rope on the crank arm so that the hammer can be stopped urgently in case of an unexpected situation.
(3) The take-off height of the upper piston shall not exceed 2.5m.
(4) During the piling process, the piling frame should be checked frequently with a line hammer and level. If the verticality deviation exceeds 1%, it must be corrected in time to avoid driving the pile at an angle.
(5) During the piling process, no one is allowed to enter within a 4m radius centered on the pile axis.
Vibrating pile hammer
The working principle of the vibrating pile hammer is to use the high-speed rotation of the motor to drive the eccentric block in the vibration box to rotate at high speed through the belt, generating a sinusoidal excitation force that changes regularly. Under the action of the excitation force, the pile moves at a certain frequency and amplitude. Vibration occurs, causing the soil around the pile to be in a "liquefied" state, thereby greatly reducing the frictional resistance of the soil to the pile, causing the pile to sink and be pulled out. This pile hammer has the advantages of high efficiency, fast speed, and convenient construction, and has been widely used in the construction of pile foundation projects.1. Structure of vibrating hammer
The main components of the vibratory hammer are the prime mover, vibrator, pile gripper and vibration reduction device.2. Key points for safe operation of vibrating hammers
(1) Before operation, the pile hammer should be tested. Check whether the insulation value of the motor and motor cable meets the requirements; check that all components in the electrical box are intact; check the tightness of the transmission belt; check whether the bolts at the connection between the holder and the vibrator are tight.(2) After the pile is inserted into the pile clamper, move the control lever to the clamping position and let the pile clamper slowly clamp the pile until the sound of oil pressure unloading is heard. During the entire operation, the joystick should always be placed in the clamping position, and the hydraulic system pressure cannot drop.
(3) For cranes that suspend pile hammers, the hook must have a safety device.
(4) When pulling out steel sheet piles, they should be pulled out in the opposite direction to the usual sinking sequence. When clamping the sheet pile, the holder should be as close as possible to the adjacent one to make it easier to pull out.
(5) After the pile clamping device clamps the pile, the pressure gauge must wait until the pressure reaches the rated value before commanding to pull it out. When the pile is pulled out 1~1.5m from the ground, the vibration should be stopped, the hanging pile should be tied with a wire rope, and then the pile hammer should be started to pull out the pile.
(6) When pulling out piles, attention must be paid to the rated lifting capacity of the crane. The estimation method is usually used, that is, the radius of gyration of the crane should be determined by the ratio of 1m to 1t of pile length.
(7) After the pile is completely pulled out, the pile clamp must not be loosened before the pile lifting wire rope is tightened.
Static pile driver
1. Structure of static pile driver
Static pile driver is a construction machine that relies on static pressure to press piles into the ground. When the static pressure is greater than the pile sinking resistance, the pile will sink into the soil. The pile driver has no vibration, no noise, no waste pollution during construction, and has little impact on the foundation and surrounding buildings. It can prevent the impact pile driver from causing damage to the pile head and pile body due to continuous hitting of piles. It is suitable for construction in soft soil strata and silt strata along the coast and rivers. Application in cities has little impact on the surrounding environment.The fully hydraulic static pile driver is mainly composed of outrigger platform structure, long ship traveling mechanism, short ship traveling mechanism, clamping mechanism, guide pile pressing mechanism, crane, hydraulic system, electrical system and operating room.
2. Key points for safe operation of static pile driver
(1) During the pile driving construction, the pile position should be inserted correctly. If there are underground obstacles that cause the pile to tilt during the driving process, the pile driver cannot be used to forcefully correct the deviation. The pile should be pulled up and reinstalled after the underground obstacles are removed. Instrumentation.(2) When the clamping mechanism and the pile side slip during the pile pressing process, the hydraulic oil pressure cannot be increased arbitrarily and the operation is forced. Instead, the cause of the slippage should be found out and effective measures must be taken before the pile pressing can continue.
(3) When the pile penetration resistance is too large and the pile cannot be pressed to the elevation, the counterweight cannot be increased arbitrarily, otherwise it will cause damage to the hydraulic components and components.
(4) When the top of the pile cannot be pressed to the designed elevation, the pile must be chiseled away. It is strictly forbidden to use a pile driver to drive the pile up.
(5) During the pile pressing process, if the surrounding soil bulges and affects the movement of the pile driver, the bulging soil in front of the pile driver should be shoveled away and should not be forced through to avoid damage to the pile driver components.
(6) During the jacking process of the pile driver, try to avoid any ship-shaped track pressing on the top of a single pile that has been embedded in the soil, otherwise the ship-shaped track will be deformed.
(7) The electrical system of the pile driver must be effectively grounded. During construction, the cables must be cared for by dedicated personnel, and the main power switch must be turned off at the end of each day.
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