Different types of shear walls used in construction

A shear wall is a structural element that provides stability and strength to a building against lateral forces such as wind and earthquakes. It consists of a wall made of reinforced concrete or wood and is designed to resist shear forces in one direction. In today’s construction, using shear walls is crucial in ensuring the safety and stability of buildings, especially in areas prone to natural disasters. With the increasing need for sustainable and resilient structures, shear walls have become a fundamental component in the design and construction of modern buildings. Their ability to provide robustness against lateral forces makes them essential in ensuring building occupants’ safety and structures’ longevity.

See also: How to create a wall structure design?

What is a shear wall?

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A shear wall is a structural element to resist lateral forces such as wind and seismic loads. It is a vertical element that extends from the foundation to the roof and is designed to transfer lateral loads to the building’s foundation, where the soil absorbs them. Shear walls are usually made of reinforced concrete or masonry and can be designed in various shapes, including rectangular, circular, or irregular shapes. They may be solid or have openings for windows and doors and are often stiffened by horizontal beams or diagonal braces to improve their performance. The design of shear walls is a crucial aspect of the structural design of buildings, as they play an essential role in ensuring the stability and safety of the structure.

Shear walls: Classification

Shear walls are structural elements that resist lateral loads, such as wind or earthquake forces, in tall buildings and other structures. They can be classified based on various criteria, including:

• The material used: Shear walls can be made of concrete, masonry, steel, wood, or a combination of materials.
• Configuration: Shear walls can be solid, lattice, or framed. Concrete shear walls are continuous and have no openings, lattice shear walls have multiple entrances, and framed shear walls have a frame structure with infill panels.
• Load-bearing capacity: Shear walls can be classified based on their load-bearing ability, including light-duty, intermediate-duty, and heavy-duty shear walls.
• Orientation: Shear walls can be vertical, inclined, or horizontal.
• Function: Shear walls can be used as a structural element or as a cladding element. Structural shear walls provide the necessary strength to resist lateral loads, while cladding shear walls only serve an aesthetic purpose and do not provide significant strength.
• Location: Shear walls can be located at the perimeter or interior of a building, or they can run vertically or horizontally.

These are some of the common ways of classifying shear walls. The choice of classification will depend on each project’s specific requirements and design considerations.

Shear walls: Types

Shear walls are structural elements that provide lateral resistance against wind and seismic loads in buildings. There are several types of shear walls, including:

Reinforced concrete shear wall

Reinforced concrete shear walls are structural elements used to resist lateral loads such as wind and earthquakes. They consist of concrete and steel reinforcement, with the concrete providing compressive strength and the steel providing tensile strength. The wall is typically designed to be taller than it is wide and has a higher strength-to-weight ratio than other lateral-load-resisting elements like concrete beams or columns.

For example, a typical reinforced concrete shear wall might be 10 feet tall and 2 feet wide, with steel rebar running vertically and horizontally to provide additional strength. The wall deforms slightly when subjected to lateral loads, but its reinforcement keeps it from collapsing.

Concrete block shear wall

A concrete block shear wall is a structural wall used to resist lateral loads such as wind and earthquakes. It is made of concrete blocks stacked one upon the other and connected by horizontal reinforcing bars and grout. The blocks act as composite materials, with the grout filling the voids between the blocks to create a monolithic wall.

An example of a concrete block shear wall would be a building with exterior walls made of concrete blocks, where the blocks are stacked in a specific pattern to resist wind and seismic forces. The wall is typically designed and tested to ensure it can withstand a specified level of load.

Steel shear wall

A steel shear wall is a structural element used in construction to resist lateral forces such as wind and earthquakes. It is typically composed of steel plates, angles and connections that create a monolithic structure that can transfer forces from one element to another. The steel shear wall is a cantilever structure that transfers lateral forces to the foundation.

For example, in a 20-storey building, the steel shear wall may be located near the elevator core, extending from the foundation to the roof. The steel plates are connected to the floor beams using high-strength bolts, creating a monolithic structure that can withstand significant lateral loads. Steel shear walls have high strength and flexibility, making them an effective solution for resisting large lateral forces and providing stability to the structure.

Plywood shear wall

A plywood shear wall is a type of structure used in building construction to resist lateral forces such as wind and earthquakes. It is made of multiple layers of wood panels or plywood glued together and placed vertically between the floor and roof. The plywood panels are anchored to the framing members with screws, creating a robust and continuous wall.

An example of a plywood shear wall can be seen in a two-storey house. The first floor has a shear wall made of two layers of plywood panels, with the panels running vertically from the foundation to the roof. The panels are anchored to the floor and roof joists, creating a strong barrier against lateral forces. This wall system provides a cost-effective and efficient way to resist lateral forces, making it a popular choice for many residential and commercial structures.

Mid-ply shear wall

A mid-ply shear wall is a type of structural wall commonly used to construct multi-storey buildings. It is composed of multiple layers of wood or other materials stacked vertically and connected through nails, screws, or adhesive. The mid-ply shear wall provides lateral stability to the structure by resisting wind and seismic forces.

An example of a mid-ply shear wall is a 9-inch concrete block wall sandwiched between two layers of drywall, with steel reinforcement running through the concrete layer. The wall would be anchored to the foundation using steel plates and brackets. This type of wall is popular due to its cost-effectiveness, ease of construction, and ability to resist strong wind and seismic forces.

How does a shear wall work?

While a comprehensive grasp of shear walls may necessitate a structural engineering background, envisioning them as wooden squares with four edges—essentially comprising two columns and two beams—can aid in comprehending their functionality. This frame effectively supports compressive loads, as forces on the upper beam are transmitted through the columns to the square’s base.

However, when excessive lateral forces are applied to its sides, the square may twist and fail unless bracing with supports is introduced. These braces are integrated into shear walls, strategically constructed to avert self-collapse. Thus, shear walls play a crucial role in safeguarding structures from potential destruction caused by lateral forces such as wind or seismic events, ensuring the resilience of homes and buildings.

In modern architectural designs, numerous features like windows, bays, doors, recesses, and open floor plans are prevalent. While these elements enhance aesthetics and functionality, they may not inherently provide the structural stability needed to withstand lateral forces. Consequently, internal shear walls are often incorporated into construction plans, fortifying structures such as houses and apartments and rendering them capable of enduring external forces while remaining safe for habitation.

Where are shear walls located?

Shear walls demonstrate optimal performance when strategically positioned symmetrically within or around the central axis of a building. To achieve symmetry, if a shear wall is present on the north side, an identical one must be placed on the south side. The spacing of shear walls in a building is influenced by factors such as the building’s size and whether the walls serve as exterior or interior components.

• Positioning within Each Half of the Building: Interior shear walls are typically situated at the center of each half of a building. This placement is particularly beneficial for larger structures like expansive houses, high-rise buildings, and skyscrapers, enhancing their ability to withstand seismic forces. Interior shear walls can manifest as core walls or box-shaped columns strategically placed in areas such as stairwells or elevators.

• Ends of the Building: Exterior shear walls are commonly found at the ends of a building. The placement of one shear wall on each end ensures the necessary symmetry, contributing to the building’s resistance against movement.

Shear walls: Advantages

• Increased stability: Shear walls provide a high level of lateral stability, which is essential in resisting wind and seismic forces.
• Cost-effective: Shear walls are relatively inexpensive compared to other lateral load-resisting systems, making them a popular choice for cost-conscious construction projects.
• Simple construction: Shear walls are easy to construct and do not require complex connections or specialised equipment.
• Flexibility: Shear walls can be designed to accommodate various architectural requirements and can be incorporated into multiple building shapes and sizes.

Shear walls: Disadvantages

• Limited space: Shear walls can take up valuable floor space, especially in multi-storey buildings where lateral stability is required on each floor.
• Reduced floor space: The placement of shear walls can reduce the amount of usable floor space in a building, which can be a disadvantage for particular structures.
• Poor aesthetic appeal: Shear walls can be visually unappealing and can detract from the overall aesthetic appeal of a building.
• Maintenance: Shear walls may require regular maintenance and inspection to ensure that they remain in good condition and can continue to resist lateral forces effectively.
• Load concentration: Shear walls concentrate lateral loads at specific points, leading to increased stress and potential failure if not adequately designed and constructed.

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