Piling works in construction of EPC projects refers to the process of creating deep foundations for buildings, equipment and structures. Piling is necessary when the soil conditions are such that traditional shallow foundations are not feasible, or when the weight of the structure requires a stronger foundation.
Type of Pile foundation
Piling is an essential aspect of construction, providing stability and support to structures built on unstable or weak soil conditions. There are three common methods of using piling types in construction, including Driven pile, Cast-in-situ pile, and Combined pile.
- Driven pile: Driven piles are prefabricated elements made of concrete, steel or timber that are driven into the ground using a pile driving rig. This method is commonly used for structures with high loads, such as bridges and tall buildings. The piles are driven into the ground using the weight of the pile driving rig and a hammer.
- Cast-in-situ pile: Cast-in-situ piles are constructed by pouring concrete into a drilled hole in the ground. This method is commonly used for smaller structures, as the equipment needed is less extensive compared to the pile driving rig used in driven piles. Cast-in-situ piles are used when the soil conditions are not suitable for driving piles.
- Combined pile: As the name suggests, the combined pile combines the benefits of both driven piles and cast-in-situ piles. The pile is partially prefabricated and partially constructed in-situ. This method is commonly used when the soil conditions are such that driving piles is not possible, but the soil is not suitable for cast-in-situ piles.
There are several types of piles used in driven pile construction, each with its own unique characteristics and application. The most common types of piles include:
- Concrete Piles: These are precast concrete members that are installed into the ground using a pile driver or hydraulic hammer. They are commonly used for heavy structures and can be designed to withstand both compression and tension forces.
- Steel Piles: Steel piles are long, slender members that are driven into the ground using a pile driver. They are often used for structures that require deep foundations and are particularly useful in situations where the soil is too soft for concrete piles.
- Timber Piles: Timber piles are made from hardwood and are typically used in situations where the soil is relatively soft and easy to penetrate. They are often used as temporary foundations, or in combination with other types of piles.
- Sheet Piles: Sheet piles are interlocking sections of steel or other materials that are driven into the ground to form a retaining wall or to create a deep foundation. They are often used for temporary works, such as excavation support, or for permanent structures, such as retaining walls and seawalls.
When it comes to the installation of driven piles, there are three commonly used methods, including impact driving, vibro-driving, and pressing or hydraulic jack-in.
- Impact driving: In this method, a heavy weight is dropped from a height to drive the pile into the ground. The impact of the weight on the pile creates energy that drives the pile into the ground.
- Vibro-driving: Vibro-driving uses a vibrating device to drive the pile into the ground. The vibration created by the device drives the pile into the soil, reducing the resistance of the soil and allowing the pile to be driven deeper.
- Pressing or hydraulic jack-in: In this method, hydraulic jacks are used to press the pile into the ground. The hydraulic jacks are attached to the pile and hydraulic pressure is used to drive the pile into the ground.
Common Driven Pile Installation Problem
During the construction of a driven pile foundation, some common pile driving problems that can occur include:
- Difficulty in driving the pile to the required depth: This occurs when the pile encounters a dense layer of soil or rock that is too hard to penetrate, causing the pile driving to stop or slow down significantly or vice versa. The indication of the problem is Blow Count is significantly higher than expected, blow count is substantially lower than expected, slightly lower blow count than expected, abrupt change or decrease in blow counts for bearing piles, piles are driving significantly deeper than expected
- Pile damage: Pile damage can occur during driving due to excessive force, impact, or bending. Damage to the pile can reduce its load-carrying capacity and can lead to failure in the future.
- Pile buckling: This occurs when a pile is driven into soils with soft layers and/or voids, causing it to bend or buckle. This can reduce its load-carrying capacity and can cause failure.
- Pile driving noise and vibration: Pile driving can generate high levels of noise and vibration, which can be disruptive to nearby residents and businesses.
- Pile driving fatigue: Pile driving can induce fatigue loading on the pile, causing it to develop cracks or other defects that can reduce its load-carrying capacity over time. The indication of the problem is concrete piles develop partial/ complete horizontal cracks, concrete pile is spalling or slabbing near the head, head of a steel or timber pile is deformed
- Pile alignment: Piles must be driven vertically and in the correct location to ensure that they can effectively support the structure. Misalignment of the piles can reduce their load-carrying capacity and can cause structural problems.
- Soil disturbance: Pile driving can disturb the soil around the pile, which can cause settlement or instability of nearby structures or foundations, it can also create lateral movement of previously Installed Piles.
In construction projects where minimal disturbance is a priority, such as in urban or residential areas or near sensitive equipment in a plant or near sensitive facility such as near Control Room, bored piles are often preferred over driven piles due to the problems associated with the latter’s installation. The installation of driven piles can produce high levels of noise and vibration, which can cause disturbance to nearby residents or existing equipment and damage to nearby structures. Bored piles, on the other hand, are installed using a drilling process that is relatively quiet and produces less vibration. This makes them a more suitable option for projects where environmental concerns are a priority. Additionally, bored piles can be installed in a variety of soil conditions and can be constructed to a wide range of depths and diameters, making them a versatile solution for foundation construction. However, it is important to note that bored pile construction also has its own set of challenges and requires proper planning and execution to ensure quality and efficiency.
Common Bored Pile Installation Problem
Bored pile installation is a widely used foundation construction technique that involves drilling a hole in the ground and filling it with concrete and reinforcement steel. Despite being a popular and efficient method, bored pile installation is not immune to challenges. One of the common issues faced during the installation of bored piles is drilling difficulties. Drilling can become a problem when the drill bit gets stuck at the bottom of the hole. This can be due to hard soil or rock formations that are difficult to penetrate. This problem can cause delays and increase costs, as additional equipment and manpower may be required to dislodge the drill bit.
Another common issue during bored pile installation is the placement of reinforcement steel. Steel bars are likely to move laterally or get dragged down during concrete pouring, which can affect the pile’s structural integrity. These issues can occur when reinforcement steel is not positioned accurately, or the concrete is not poured evenly. Therefore, careful planning and accurate placement of reinforcement steel are essential to avoid such problems.
Excessive water in the borehole is another issue that can occur during bored pile installation. The presence of water can create instability and weaken the soil. It can also make it difficult to drill and pour concrete. If excessive water is present, utilization of bentonite would eliminate this problem.
Borehole wall collapse is also a common problem during bored pile installation. The instability of the soil and the pressure exerted on the borehole walls during drilling can cause the walls to collapse. This can result in delays and additional costs. To avoid such issues, proper casing need to be installed.
Lastly, bored pile installation can also result in pile integrity problems. These issues can include voids in the concrete pile, soil inclusion, necking, and bulging. These problems can occur due to improper drilling or concrete pouring techniques. They can weaken the pile’s strength and stability and may require remedial work to address.
Quality Control and Quality Assurance
Pile foundation quality control and quality assurance testing are crucial steps in ensuring the safety and reliability of any construction project. Pile foundations are an essential element of many structures and are responsible for bearing the load and transferring it to the ground. Therefore, it is essential to conduct a series of tests to assess the quality and integrity of pile foundations.
One of the most common testing methods is the Static Load Test, The static load test is a fundamental quality control and assurance testing method for pile foundations that is widely used in the construction industry. This test involves applying a controlled load to the pile and measuring its displacement and settlement using sensors. The load is applied gradually over a period of time, allowing the pile to adjust and settle. The results of the test can provide valuable information about the performance and load-bearing capacity of the pile.
A Pile Loading Test is performed by applying increasing loads to a pile until it reaches its maximum load-bearing capacity, or until it fails. The load is increased incrementally and the pile is monitored for any signs of movement or failure. The results of the test help engineers to determine the load-bearing capacity of the pile and to design the structure accordingly.
The static load test can be conducted in different configurations depending on the type of load and the orientation of the pile. Three common configurations of static load testing are compression, tension, and lateral load testing. Each configuration is designed to assess different aspects of the pile’s behavior and performance under different types of loads.
Compression testing is the most common configuration of the static load test and involves applying a vertical load to the pile. The load is typically applied using hydraulic jacks, and the displacement and settlement of the pile are measured using sensors attached to the pile and to the surrounding soil. This testing method is useful in determining the ultimate bearing capacity of the pile and its behavior under compression loads.
Tension testing is another configuration of the static load test that is used to evaluate the performance of the pile under tensile loads. In this configuration, the load is applied to the pile in the opposite direction of gravity, and the displacement and settlement are measured using sensors attached to the pile and the surrounding soil. Tension testing can be useful in identifying any potential issues with the pile’s anchorage and ensuring that it can withstand tensile loads.
Lateral load testing is another configuration of the static load test that is used to evaluate the pile’s behavior under horizontal loads. In this configuration, the load is applied to the pile in a horizontal direction, and the resulting displacement and settlement are measured using sensors attached to the pile and the surrounding soil. Lateral load testing can be useful in assessing the pile’s lateral stiffness and deformation characteristics.
Another testing method is the Dynamic Load Test, which uses a Pile Dynamic Analyzer (PDA) to assess the capacity of the pile to bear the load for the structure. This method is quick and accurate, and it is commonly used in situations where it is difficult to perform a static load test. The dynamic load test is particularly useful in assessing the performance of the pile under the effects of vibrations, such as those caused by machinery or seismic activity.
Pile Integrity Test (PIT) is another important quality control and assurance testing method for pile foundations. The Pile Integrity Test (PIT) is a non-destructive testing method that is commonly used to evaluate the integrity and continuity of deep foundation elements such as piles. This testing method involves striking the pile head with a light handheld hammer and recording the response of the pile using a motion transducer coupled to the pile head. This test can help identify any changes in the cross-sectional area, continuity, or length of the pile, which may indicate the presence of defects or damage. The PIT is a widely used testing method due to its simplicity, portability, and ability to quickly assess the integrity of the foundation element. However, it has some limitations, including its sensitivity to noise and variability in the results due to factors such as pile type, length, and soil conditions. Therefore, the results of the PIT should always be interpreted by a qualified engineer or technician who is familiar with the test procedure and its limitations.
below is some of subcontractor to do piling works:
Berdikari Pondasi Perkasa, PT
Established in 1984, provide services for both onshore piling and near shore piling for both driven and bored pile.
Contact: Phone: (62 21) 5662756 – 5662757 – 5664415 – 5663952 Fax: (62 21) 5663058 – 5677560
Website: www.ptbppid.com
Frankipile Indonesia, PT
Established in 1973, PT. FRANKIPILE INDONESIA exist as specialist in Foundation and Geotechnical Engineering Contractor.
Contact: Phone: (021) 5366-0778 Fax: (021) 5366 0779 Email: franki@indo.net.id
Website: www.frankipile.co.id
Hume Concrete Indonesia, PT
Established in 1991, Hume Concrete Indonesia use Nippon Hume Corporation concrete spun pile construction technology as its basis.
Contact: Phone. 62-21 893-4024 – Fax. 62-21 893 4222
Website: www.humeconcrete.com
Indonesia Pondasi Raya, PT
Established in 1977, provide services of piling, pile testing, retaining wall and ground improvement
Contact: Phone +(62 21) 4603253 (Hunting) Fax +(62 21) 4604390, +6221 4604393
Website: www.indopora.com
Insema Sunly Engineering, PT
Established in 1986 and continue to grow.
Contact: Phone: 62-21-5870657 Email: contact@sunlyengineering.com / contact@insemafoundation.com
Website: www.sunlyengineering.com
JHS Piling System, PT
Established in 1982 and continue to grow. JHS has a patent for joint of square precast pre-stressed piles
Contact: Phone: (021) 461 2030; Fax: (021) 440 1090 Email : jhspile@cbn.net.id
Website: www.jhs-system.com
Sanggar Adhisarana Tehnik, PT
Specialize in onshore piling and nearshore piling
Contact: Phone: (62 31) 828 3481 ; (62 31) 828 7671 Email: sastek@indosat.net.id
Website: www.sastek.co.id
Sunway Yasa Mandiri, PT
Established in 2010, To ensure the qualities of the piles Sunway have their own casting yard and produce the piles by themselves
Contact: Phone / Fax : +62.21.45874148 Email: marketing@sym.co.id
Website: www.sym.co.id
Teno Indonesia, PT
Established in 1994, Teno Indonesia develops the use of a new version of Diesel Hammers and Hydraulic Hammer such as : BSP, JUNTTAN and Hydraquip which is environmental friendly.
Contact: Phone: (62 31) 593 6240-42 Fax : (62 31) 593 6243 Email : tenoindo@gmail.com
Website: www.teno-indonesia.com