Building Earthquake Resistant Structures

Fundamentals of Earthquake-Resistant Structures

Earthquake-resistant structures are critical for ensuring life and property safety. The choice of a regular load-bearing system primarily relates to architectural design. Both in plan and vertical direction, architectural design should be organized to allow the use of simple and continuous load-bearing systems, free from complexity. This is the first condition for successful structural design against earthquakes. At this point, it is appropriate to state that the design of earthquake-resistant buildings can be achieved through the joint efforts of architects, structural engineers, and even other disciplines. This issue needs particular attention in our country, which is located in an earthquake zone. Some fundamental principles of our projects that are both earthquake-resistant and modern in architecture include:

Choosing a Solid Ground: The foremost factor in ensuring safety during earthquakes is the quality of the ground on which a structure is built. This is followed closely by the design of earthquake-resistant buildings. Local soil characteristics, shaped by geological factors such as rock type distribution, tectonics (faults, fractures, folds), topography, geomorphology, and groundwater behavior, play a crucial role in how structures perform during seismic events.

Different soil types and the underlying rock influence the extent of damage experienced during earthquakes of equal intensity, as historical data has shown. This highlights that the properties of the soil can significantly affect the transmission of earthquake waves and, consequently, the performance of structures.

Local soil characteristics can lead to various damaging effects, including ground amplification, liquefaction, landslides, and ground settlement. To address these challenges, key actions must include:

• Detailed examination of the geological structure of the land where the building will be constructed.
• Avoiding soft and loose soils.
• Implementing ground improvement methods when necessary.

Appropriate Structural Design Buildings must redistribute the forces passing through them during a seismic event to withstand destruction. Shear walls, cross braces, diaphragms, and moment-resisting frames are crucial in strengthening a building. Shear walls are a beneficial construction technology that helps transfer earthquake forces. These walls consist of multiple panels that help maintain the shape of a building during movement. Shear walls are typically supported by diagonal cross braces made of steel, which can resist compression and tension forces.

Diaphragms are also central to the structure of the building. Diaphragms, made up of the floors, roofs, and slabs placed above them, help dissipate stress from the ground and push forces into the building's vertical structural elements.

Moment-resisting frames provide extra flexibility in a building's design. These structures are placed between the joints of a building, allowing columns and beams to bend while keeping the joints rigid. This way, the building can withstand the forces of a larger earthquake while allowing designers the freedom to organize structural elements. Key design elements should include:

• Preference for symmetrical and simply geometrical structures.
• The center of mass should overlap with the center of stiffness.
• Vertical load-bearing elements should be continuous.

Use of Quality Materials - Steel and Wood: A material's ability to withstand compression and vibration requires it to have high ductility, allowing it to endure significant deformation and stress. Modern buildings are generally constructed with structural steel, a component that allows bending without breaking. Wood, due to its high strength relative to its lightweight structure, is surprisingly ductile.

Innovative Materials Scientists: and engineers are developing new construction materials that preserve their shape even more. Innovations like shape memory alloys can withstand heavy loads and return to their original shapes. Additionally, fiber-reinforced plastic wraps made from various polymers can be applied around columns to provide up to 38% extra strength and ductility. Engineers are also turning to natural elements to help strengthen buildings. The adhesive yet strong fibers of mussels and the strength-to-weight ratio of spider silk show promising potential for construction. Bamboo and 3D-printed materials can serve as lightweight, interlocking structures that provide even greater resistance. Material selections should include:

• Use of high-strength concrete and steel.
• Continuous monitoring of material quality.
• Preference for lightweight and durable construction materials.

Flexible Structural Systems: One way to resist earthquake forces is through a method called base isolation, which involves constructing a building on flexible pads made of steel, rubber, and lead. During an earthquake, when the ground moves, the building itself remains stable while the isolators vibrate. This helps to reduce the impact of seismic waves and effectively prevents them from propagating through the building. High ductility structural elements should be used, and energy-dissipating systems should be integrated to increase the building's capacity to absorb earthquake energy.

Proper Detailing: Relative displacements and deflections that occur under lateral loads increase second-order moments in the load-bearing system. Shear walls mitigate this negative impact. However, for this, it is important to evenly distribute vertical load-bearing elements, especially shear walls and large columns, in the x and y directions. Since infill walls contribute much less to the rigidity of the system compared to shear walls, their arrangements and thus the distribution of frame openings in different directions are not as effective as that of shear walls and large columns. In summary, detailing should pay attention to the following:

• Strengthening column-beam junctions.
• Strategically placing shear walls.
• Designing foundations according to building loads and soil characteristics.

Regular Maintenance and Inspection Minor adjustments and changes in the maintenance process can reveal deficiencies in energy efficiency. For example, reducing heat loss from a piece of equipment can enhance operational efficiency and contribute to reduced deterioration rates of components and energy bills. Improvements in systems or energy efficiency can also enhance the overall sustainability of the building and help reduce energy bills potentially qualifying for public service discounts. Having a sustainable building is particularly important for owners looking to promote a sense of eco-responsibility.

When building owners prioritize maintenance, the results are clear: cost savings increase, and occupants enjoy a safe and comfortable environment.

• Periodic inspections of buildings.
• Strengthening works as needed.
• Securing non-structural elements (false ceilings, cabinets, etc.).

The ability of a structure to remain standing under the effects of very strong earthquakes, as defined in regulations, depends significantly on its capacity to absorb energy, along with having a certain strength in the structure. These two structural properties are also necessary for the structural behavior mentioned in the second stage. The linear elastic behavior anticipated for the first stage is entirely ensured by the sufficient strength of the structural elements.

Yükselen Mimari, one of the leading construction companies in Antalya, meticulously applies these principles. The company prioritizes a safe construction approach in its residential projects in Antalya by building earthquake-resistant structures. Particularly when reflecting on the painful experiences related to earthquakes, our tendency to prefer earthquake-resistant homes during the buying or renting process is gradually increasing. Therefore, being aware of whether the homes we spend a significant part of our lives in are sufficiently earthquake-resistant and the characteristics that place a house in a high-risk group regarding earthquakes can help us avoid the negative consequences of this dangerous and unavoidable disaster and enable us to be more informed.

Yükselen Mimari's projects in Antalya stand out not only aesthetically but also in terms of safety and durability. The company closely follows modern architectural trends while also keeping pace with the latest developments in earthquake engineering. Knowing that the buildings we inhabit are safe from earthquakes is crucial for leading a comfortable and peaceful life.

In conclusion, constructing earthquake-resistant structures is not just an engineering issue but also a social responsibility. Conscious construction firms like Yükselen Mimari are aware of this responsibility and continue to offer safe and durable buildings in their residential projects in Antalya.