EQUIPMENT BORED PILING How to and what equipment are used in steel bored pile driving and steel sheet piling, moreover.
How to and what equipment are used in steel bored pile driving and steel sheet piling, moreover.
EQUIPMENT USED IN BORED PILING
There is various piling equipment used in bored pile driving. This equipment depends on the bored piling system that is best suited to use. The two general systems in bored piling are replacement piling and displacement piling.
In replacement piling, equipment is used to remove the soil on the piling location to form a hole for the bored pile. On the other hand, in displacement piling piles are driven, jacked, vibrated, or screwed into the ground. Displacing the material around the pile shaft outwards and inwards, instead of removing it.
How to and what equipment are used in steel bored pile driving and steel sheet piling? Linsteel Philippines will tell you how.
How to and what equipment are used in steel bored pile driving and steel sheet piling? Linsteel Philippines will tell you how.
EQUIPMENT FOR REPLACEMENT BORED PILE DRIVING
Replacement bored pile uses rotary auger equipment called a piling rig. The piling rig is equipped with a telescopic arm known as a Kelly bar. The Kelly bar slides vertically and holds an auger bucket at the end. The auger is a drilling device that includes a rotating helical screw blade that digs the soil. A reinforced compact concrete bored pile will replace the soil. This will then serve as the foundation for the building.
How to and what equipment are used in steel bored pile driving and steel sheet piling? Linsteel Philippines will tell you how.
How to and what equipment are used in steel bored pile driving and steel sheet piling? Linsteel Philippines will tell you how.
EQUIPMENT FOR DISPLACEMENT BORED PILE DRIVING
On the other hand, displacement or driven piles require pile drivers also known as pile hammers. The systems in this driving can either be (a) impact driving or (b) vibro-driving.
A. IMPACT DRIVING
The main equipment that can be used in impact driving is a drop hammer, air/steam hammer, hydraulic, or diesel hammer.
Drop hammer is the oldest type of pile driving hammer. The hammer is connected to a cable that is attached to a winch on the crane. This raises the hammer to the desired stroke. The winch has a clutch on it that allows the operator to release the hammer. The hammer falls by its own weight and strikes a pile cap of the pile. The available energy per blow of a drop hammer is the product of the piston (ram) weight times the drop height. Standard ram weights range from 500 to 10,000 lbs. The typical drop height is approximately 1.2 meters. Drop hammers are typically used on very small piling projects.
Advantages of Drop Hammers
1. Firstly, the simplicity of operation.
2. Ease of mobilization and demobilization.
3. Low investment and maintenance costs.
4. Lastly, the drop height can easily be changed.
On-going impact driving at the site.
An impact driver striking the head of a bored pile for instance.
How to and what equipment are used in steel bored pile driving and steel sheet piling? Linsteel Philippines will tell you how.
How to and what equipment are used in steel bored pile driving and steel sheet piling? Linsteel Philippines will tell you how.
Air or Steam Hammers are essentially drop hammers that use pressurized air or steam as hoisting cable. The ram is usually a short, stocky block of steel that is connected at its top. It is guided by columns or inside a guiding enclosure. The operating rate of single acting air/steam hammers ranges between 35 and 60 blows per minute. This rate is comparable to most other hammer types that lack downward assist.
Advantages of Single Acting Air/Steam Hammers
1. Higher rate of blows per minute than drop hammers.
2. Relatively consistent operation.
Disadvantages of Single Acting Air/Steam Hammers
1. Additional equipment needed such as boiler, compressor, hoses, and etc.
2. Relatively heavy hammer that requires higher crane.
A head of a steam or air hammer.
Model exhibiting the flow of air inside a piston hammer.
Parts of an Air Hammer Head
Hydraulic Impact Hammer incorporates the use of an external energy source to lift the hammer to the top of its stroke. The liquid applies pressure to the piston to move the ram. Impact hammers can be single acting, double acting, differential acting, or other variations. A hydraulic hammer is a modern type of piling hammer that used liquid instead of diesel or air. Hydraulic hammers are more environmentally acceptable than older, less efficient hammers because they generate less noise and pollutants.
A hydraulic impact hammer.
Diesel hammer consists of a long slender piston, which moves inside a cylinder. The cylinder is open at its upper end, thus allowing the ram to partially emerge from the cylinder. The open-end diesel hammer is also called single-acting since the ram falls only under gravity.
Advantages of Single Acting (Open End) Diesel Hammers
1. Firstly, self-contained unit does not require additional equipment.
2. Secondly, increasing strokes in hard driving provide increasing energies.
3. Low strokes in easy driving protect concrete piles.
4. Relatively low ram weight compared to energy (high strokes.)
Disadvantages of Single Acting (Open End) Diesel Hammers
1. Stroke dependent on hammer-pile-soil system.
2. Relatively low blow rates with high strokes.
3. Potential for environmental problems (very dependent upon how hammer is outfitted with fuel and lubricants).
A diesel hammer.
How to and what equipment are used in steel bored pile driving and steel sheet piling? Linsteel Philippines will tell you how.
How to and what equipment are used in steel bored pile driving and steel sheet piling? Linsteel Philippines will tell you how.
The ram pushes the impact block, hammer cushion, helmet, and pile head rapidly downward. This allows the cylinder to fall under gravity. The impact block separates from the ram within a very short time. The pressure of the combusting air-fuel mixture will cause further separation as the ram is forced upward.
Parts of a diesel piston hammer.
B. VIBRO DRIVING
An oscillating driver is clamped to the top of the pile to induce vibrations in the pile. This will reduce friction on the soil along the sides of the pile. Because of this, the pile can be inserted into the ground with little extra application of force.
Vibratory pile hammers contain a system of counter-rotating eccentric weights, powered by hydraulic motors. These are designed to make horizontal vibrations to cancel out, while vertical vibrations are transmitted into the pile. The pile driving machine positioned over the pile with an excavator or crane. Vibratory hammers can also extract a pile. Vibratory pile drivers are often chosen to mitigate noise, as when the construction is near residences or office buildings. Also, when there is insufficient vertical clearance to permit the use of a conventional pile hammer. For example, is when retrofitting additional piles to a bridge column or abutment footing. The vibration rate depends on the soil conditions and other factors such as power requirements and equipment cost.
A vibratory hammer driving a steel casing.
How to and what equipment are used in steel bored pile driving and steel sheet piling? Linsteel Philippines will tell you how.
How to and what equipment are used in steel bored pile driving and steel sheet piling? Linsteel Philippines will tell you how.
ACCESSORIES USED IN BORED PILING
HAMMER CUSION AND PILE CUSHION
All impact pile driving equipment except drop hammers shall be equipped with a suitable thickness of hammer and pile cushion material. This is to prevent damage to the hammer or pile.
A vibratory hammer driving a steel casing.
HELMET
The helmets distribute the hammer blow uniformly and concentrically to the pile head. The surface of the helmet in contact with the pile shall be plane and smooth and must be aligned parallel with the hammer base and the pile top. The helmet shall fit the pile head in such a manner as to maintain concentric alignment of hammer and pile.
A pile helmet used to distribute the impact of the piston on the bored pile.
Parts of a piston pile helmet assembly
How to and what equipment are used in steel bored pile driving and steel sheet piling? Linsteel Philippines will tell you how.
How to and what equipment are used in steel bored pile driving and steel sheet piling? Linsteel Philippines will tell you how.
