What is the proper vinyl sheet pile driving method for different soil types?

“Pitch and drive” method is the most practical way of pile driving in loose soils especially when using short piles. Also called “set and drive”, this method installs piles one by one. However, with only one interlock in control, sheet piles have high tendencies of rotating from the axis and leaning forward or backward. Panel driving is recommended for the dense deposit of sands and compact cohesive soils such as heavy clay or in presence of obstructions. In this method, a number of piles are interlocked together before driving. The panel of piles is supported by guide frames and driven gradually in sequence, sometimes in a staggered manner. The method can achieve installations of longer piles in more difficult ground conditions with better results in sheet pile alignment and verticality. In cases of difficult ground conditions such as hard strata and the presence of obstructions, driving assistance is employed along with a proper selection of driving method and equipment. Jetting and drilling help by loosening or eliminating obstructions by creating pressure right under the tip of the sheet pile being driven. Long and slender PVC sheet piles require steel mandrels as supports when driven in such conditions. Mandrel, which shape is similar to sheet pile profiles, increases the rigidity of Plastic Sheet Pile and supports the weight of the driving equipment such as a vibro-hammer.

What is the proper machine to drive piles in different conditions?

Impact driving is suitable for all soil types but appears to create the highest degree of stress to sheet piles. It is more appropriate to cohesive soils and soft soils such as silts and peats, loose medium to coarse sand, and gravels free of rock inclusions. Drop hammers such as the hydraulic hammer are the common types of impact-driving machinery. Driving using vibratory hammers is ideal for non-cohesive or granular soils such as soft soils and round-grained sand or gravel. It has also shown satisfactory performance in sandy, silty, or softer clay soils. It is less effective in angular-grained materials and soils with a firm consistency. With the introduction of vibration, however, the sub-soil can be further compacted, increasing penetration resistance and ultimately-refusal. If this is the case, driving aids like jetting and drilling might be necessary.

What are the pvc sheet pile selection criteria for soil condition of different hardness?

General rule of the thumb: “the harder the soil, the stronger and stiffer sheet pile section should be used”. Driveability of a pile section is a consequence of its cross-sectional properties (thickness, depth, and width), designed shape, length, grade, and the applied load. Hardness of soil strata characterized by SPT or CPT values is used to predict soil resistance which is essential in the calculation of driving force to be applied. Knowing the range of force from the selected driving machine, corresponding sheet pile sections can be picked according to their yield strength and elastic modulus.

How should I choose a sheet pile section for soils with, say, SPT Value, N=30? Can I still consider using vinyl or shift to steel?

Every sheet pile material has a design purpose, strengths, and areas of improvement. The availability of different materials denotes the need for a special material for a specific application. Plastic or synthetic sheet piles for example are known for being light and corrosion-resistant; Steel sheet piles are recognized for their extraordinary strength and versatility; and so on.

DESIGNS AND CONSIDERATIONS FOR SEASHORE PROTECTION, THE ESC WAY.

ESC Group

12 minutes ago5 min read

The seashore is a dynamic and diverse environment; it refers to the land adjacent to the sea. It includes the land between the high-water and low-water marks, often characterized by sandy, stony, or rocky terrain.

The rise and fall of tides cause different parts of the shoreline to be exposed to wave action at various times. This can lead to erosion in some areas and deposition of sediments in others, constantly reshaping the coastline. Erosion can lead to the gradual loss of land, threatening homes and infrastructure. These areas are prone to flooding, especially during high tides, storm surges, and heavy rainfall. This can cause significant property damage and disrupt daily life. The harsh environment can increase wear and tear on buildings and infrastructure, resulting in higher maintenance and repair costs. Moreover, saltwater can infiltrate freshwater supplies, affecting water quality and agricultural activities.

ESC understands the risks mentioned that prompted the need for seashore protection. Seashore protection involves various methods and structures designed to prevent erosion, manage sediment, and protect coastal areas from the impacts of saltwater, waves, tides, floods, and storms.

Common techniques of seashore protection include SEAWALLS, TIDEWALLS, BULKHEADS, BREAKWATERS, GROINS, AND REVETMENTS. Available applications, the ESC Way.

SEAWALL

A seawall is a coastal defense structure designed to protect land and property from the effects of tides, waves, and storm surges. Seawalls prevent the erosion of shorelines by absorbing and reflecting wave energy into the sea. They act as barriers against flooding, especially during high tides and storm surges.

Seawalls safeguard coastal properties and infrastructure from damage caused by the sea. This can be vertical, curved, or stepped. Some are rock or rubble; some are concrete. However, the most practical materials used are steel or vinyl, which provide flexibility and ease of installation. They offer efficient installation and, depending on the chosen material, can serve as an eco-friendly solution for coastal defense.

TIDEWALLS

Tidewalls are a type of vinyl seawall system used for coastal protection. They are made from high-quality, UV-stabilized PVC (polyvinyl chloride), which offers excellent durability and resistance to environmental factors. They are designed to be thicker and deeper than many alternatives, providing enhanced structural strength and performance.

Tidewalls are often more affordable than traditional materials like steel, wood, or concrete while offering long-lasting protection. They can be used in various applications, including coastal erosion control, flood protection, and as cut-off walls to prevent subterranean water movement. Tidewalls can be installed using various methods, including driving sheets into the ground with a plate compactor or using compression driving in softer soils

BULKHEADS

Bulkheads are vertical structures designed to retain soil and prevent erosion along shorelines. They are commonly used in coastal engineering to protect land and property from the effects of waves and tides. Bulkheads prevent the sliding or erosion of soil, maintaining the stability of the land behind them. They provide protection from light to moderate wave action, helping to reduce erosion at the base of coastal bluffs and other vulnerable areas.

Bulkheads can protect against flooding, particularly in areas prone to high tides and storm surges. One type of bulkhead is supported by anchors or piles driven into the ground, providing stability without the need for additional support structures. Bulkheads can be made from various materials, including steel, which provides high strength and durability and is suitable for more demanding environments. Vinyl and composite materials were highly considered for modern bulkhead designs as they offer resistance to corrosion and aesthetic value.

BREAKWATERS

vinyl and composite materials for seawall

Breakwaters are structures built offshore to protect coastal areas, harbors, and anchorages from the force of waves. The purpose of breakwater is to reduce the intensity of wave action in inshore waters, creating calmer areas behind them. This helps protect the shoreline from erosion and provides safe harborage for boats. By reducing wave energy, breakwaters can also influence sediment transport, leading to sediment deposition in the sheltered areas behind them.

There are different types of breakwaters, one of which is fixed breakwater, a permanent structure built from rock, concrete, or steel. Steel is recommended for some designs for its strength and resistance to harsh marine conditions.

GROINS

seashore protection using steel sheet pile

Groins are structures built perpendicular to the shoreline, extending from the beach into the water. Their primary purpose is to manage sediment movement and reduce erosion. Groin’s primary function is to trap sand moving along the coast due to longshore drift, which is the movement of sediment parallel to the shoreline caused by wave action. By capturing this sand, groins help to build up and maintain the beach on their updraft side. By trapping sediment, groins help to reduce erosion on the beach where they are installed.

Groins can be straight or angled, depending on the specific needs of the shoreline. Permeable groins allow some water and sediment to pass through, while impermeable groins block most of the flow. Steel is used for this application for its strength and resistance to harsh marine conditions.

REVETMENTS

Revetments are structures placed on banks or shorelines to absorb and dissipate the energy of incoming waves, thereby reducing erosion and protecting the land behind them. Revetments protect shorelines from erosion by absorbing wave energy and reducing the impact on the land. They also help stabilize slopes and prevent landslides or soil erosion in coastal areas. The outer layer of the revetment, typically made of large stones or concrete blocks, is designed to absorb wave energy. Another layer typically called the filter layer, is beneath the armor that prevents soil from being washed away while allowing water to drain. Additional support is at the base of the revetment to prevent undermining and ensure stability.

Revetments can be constructed using various materials, each chosen based on factors like durability, cost, and environmental impact. ESC offers vinyl and composite materials for this application. These materials offer resistance to corrosion and are often used in modern revetment designs. They are lightweight and can be easier to install compared to traditional materials.

SEASHORE PROTECTION, THE ESC WAY

Both vinyl and steel sheet piles offer distinct advantages for seashore protection.

Here's a comparison of their benefits:

ESC Vinyl Sheet Piles

Corrosion Resistance: Vinyl sheet piles are highly resistant to corrosion, making them ideal for marine environments where exposure to saltwater can cause significant damage to other material
Cost-Effective: Vinyl sheet piles are generally more affordable than steel, both in terms of initial cost and long-term maintenance. They can be up to five times cheaper than steel.
Lightweight: They are much lighter than steel, making them easier to handle, transport, and install
Environmental Impact: Vinyl sheet piles can be made from recycled materials and are often considered more environmentally friendly. They are designed to prevent the leaching of harmful chemicals into the water.
Resistance to Marine Borers and Rot: Vinyl sheet piles are impervious to marine borers, the organisms that attack materials in the marine environment. Vinyl does not rot or decay over time, ensuring the longevity of seashore protection