Retaining walls are structural systems that hold back soil, water, and other materials while maintaining integrity under extreme loading conditions. These essential engineered structures enable modern construction, marine infrastructure, and civil engineering projects to overcome challenging terrain and optimize valuable space. While retaining walls can be constructed from concrete, timber, and masonry, steel retaining wall systems deliver superior strength, unmatched versatility, and proven long-term performance for the most demanding applications.
Four Primary Types of Retaining Walls
Understanding the various types of retaining wall systems enables engineers and contractors to select the most suitable solution for specific project requirements and site conditions.
- Cantilevered Retaining Walls: The most straightforward approach for moderate-height applications, typically ranging from 8 to 15 feet in exposed height. These walls derive their stability entirely from the embedded foundation portion, requiring no external bracing or anchoring systems. The structural design relies on a cantilever principle following a 1:2 ratio of exposed height to embedded depth, making them ideal for seawalls, bulkheads, and moderate-height barriers.
- Anchored Retaining Walls: Become necessary when wall heights exceed 15 feet or when soil conditions require additional lateral support. These systems incorporate external anchoring or bracing elements that reduce wall deflection, enabling the construction of taller structures. The typical design ratio shifts to approximately 1:1 for exposed height to embedded depth, though actual proportions depend on soil conditions, groundwater levels, and applied loads.
- Combined Wall Systems: Address the most challenging retaining wall applications where standard sheet pile walls cannot provide adequate structural capacity. These systems integrate primary structural elements, known as king piles, with secondary sheet pile elements to achieve the required stiffness and bending resistance. Combined walls accommodate extreme loads and significant depths, making them essential for major marine facilities and heavy industrial sites.
- Toe Walls: Offer an innovative retrofit solution for existing waterfront structures requiring deeper dredging to accommodate larger vessels. Rather than complete replacement of existing bulkheads or seawalls, toe walls are driven below the water level at the base of existing structures, providing additional depth needed for vessel berthing while stabilizing existing infrastructure.
Steel Retaining Wall Components and Materials
Steel retaining wall systems integrate multiple specialized components engineered to work together as structural solutions.
- Steel Sheet Piling: Forms the primary structural element in most steel retaining wall applications through interlocking structural sections that create continuous walls capable of withstanding lateral earth pressures. Z-shaped sheet pile walls are the most common profile in North America, with interlocks positioned away from the neutral axis to maximize strength-to-weight ratios.
- Structural Steel Elements: Provide the backbone for combined wall systems and specialized applications. Large diameter pipe and wide flange beams serve as king piles in combination systems, offering exceptional moment resistance and load-carrying capacity. Pipe piles accommodate the highest-capacity applications, available in diameters ranging from several inches to over ten feet, with wall thicknesses engineered for specific structural requirements.
- Anchoring Systems: Enable the construction of tall retaining walls and provide essential lateral support through tie rods manufactured from high-strength threaded bars, grouted anchors for cut or excavated walls, waler systems that distribute anchor loads across multiple sheet pile walls, and battered pile systems that provide angled support for space-constrained applications.
- Steel Grades and Specifications: Steel grades are carefully selected to match environmental conditions and structural requirements. Standard grade, ASTM A572, provides reliable performance for most applications, with yield strengths ranging from 50 to 65 ksi. High-strength steel grades extend capabilities up to 150 ksi for specialized applications, while steels such as ASTM A690 and A588 offer reduced corrosion rates in marine and atmospheric conditions.
Where Retaining Walls Are Essential
Retaining walls are necessary infrastructure across diverse industries, enabling construction in challenging environments where soil stability and space optimization are paramount.
- Marine and Waterfront Construction: Port facilities, bulk terminals, seawalls, and coastal protection systems that must withstand vessel impacts, crane loads, wave forces, and corrosive saltwater environments
- Transportation Infrastructure: Highway retaining walls, railroad embankment support, and bridge approach structures enabling safe passage through challenging terrain
- Commercial and Industrial: Underground parking structures, deep building foundations, and equipment support systems that maximize usable space while protecting adjacent properties
- Heavy Civil Projects: Deep excavation support, flood protection systems, and major infrastructure requiring extreme load capacity and long-term structural integrity
These applications require engineered solutions capable of withstanding significant lateral earth pressures, environmental stresses, and decades of reliable service while maintaining public safety and operational functionality.
Advantages of Steel Retaining Wall Systems
Steel retaining walls offer distinct advantages that make them the preferred choice for challenging applications:
- Superior Strength-to-Weight Ratio: Enables construction of tall walls with relatively lightweight sections, reducing foundation requirements and installation equipment demands
- Field Adaptability: Allows for modifications during construction to accommodate unforeseen conditions or design changes, providing flexibility that other materials cannot match
- Proven Environmental Performance: Delivers reliable performance in harsh marine and industrial environments while maintaining structural integrity over decades of service
- Environmental Sustainability: Complete recyclability makes steel an environmentally responsible choice, with products manufactured from near 100% recycled content supporting sustainable construction practices
These advantages position steel as the optimal material for retaining wall applications where performance, durability, and sustainability are critical project requirements. The combination of engineering excellence and environmental responsibility makes steel retaining walls the smart choice for infrastructure projects designed to serve communities for generations.
Your True Project Partner for Steel Retaining Walls
Nucor Skyline is North America's leading steel foundation manufacturer, serving the construction industry since 1978 with retaining wall solutions and unparalleled engineering expertise. Our knowledgeable engineering team works with owners, engineers, and contractors long before ground is broken, proposing solutions throughout all aspects of design, material selection, installation, and construction sequencing.
With manufacturing and coating facilities strategically located in Arkansas, Illinois, Mississippi, New Jersey, Ohio, Pennsylvania, and Washington, we ensure reliable material supply and consistent quality for projects of any scale. Our extensive product range includes steel sheet piling, H-piles, pipe piles, micropiles, threaded bars, strand anchors, and combined wall systems—all manufactured to the highest industry standards and backed by technical support.
Our relationship with the industry extends beyond sales—we provide on-site assistance, field engineering support, and problem-solving expertise to ensure successful project completion. From initial consultation through construction completion, Nucor Skyline delivers the integrated solutions and partnership approach that complex retaining wall projects demand.
Frequently Asked Questions
How do you determine the appropriate type of retaining wall for a project?
Wall selection depends on height requirements, soil conditions, and loading scenarios. Cantilevered walls work for heights up to 15 feet, while taller applications require anchored or combined systems. A geotechnical engineer should evaluate site-specific factors for optimal solutions.
What are the main advantages of steel retaining walls?
Steel offers superior strength-to-weight ratios, enabling tall walls with lightweight sections. Steel provides exceptional field adaptability and faster installation than concrete systems. Complete recyclability makes steel an environmentally sustainable infrastructure choice.
What structural steel shapes are used in retaining wall construction?
Large diameter pipe and wide flange steel beams serve as king piles in combined systems for heavy-duty applications. These structural steel shapes offer exceptional moment resistance and load capacity. Steel beams also function as walers to distribute loads in anchored systems.