What is a Structural Strengthening Project?

A structural strengthening project is an engineering study designed to enhance the durability of buildings, particularly those at risk of earthquakes, by identifying structural weaknesses and implementing repair and reinforcement methods. The project evaluates the building’s performance against natural disasters like earthquakes, identifies vulnerable elements, and strengthens them to make the structure safer.

What is the Place of Structural Strengthening Projects in Legislation?

The place of structural strengthening projects is primarily defined in various legal regulations, notably the Turkish Building Earthquake Code. Chapter 15 of Turkish Building Earthquake Code, titled “Special Rules for the Evaluation and Strengthening Design of Existing Building Systems Under Earthquake Effects,“ details the assessment and strengthening of existing buildings, covering data collection, damage limits, earthquake calculation methods, and strengthening rules. Additionally, Law No. 6306 on the Transformation of Areas Under Disaster Risk encourages the strengthening of risky structures, while Law No. 4708 on Building Inspection regulates the permitting and supervision processes for strengthening. These regulations, though not mandatory, are recommended, especially in high-risk areas, and require administrative permits.

How is a Structural Strengthening Project Prepared?

A structural strengthening project is prepared systematically, considering the requirements of the legislation, through the following steps.

  • Architectural and Structural Analysis of the Building
  • Material and Reinforcement Detection
  • Risk Mapping and Determining the Need for Strengthening
  • Determining Strengthening Methods
  • Project Delivery and Implementation

Architectural and Structural Analysis of the Building

The building’s existing plans, usage purpose, internal arrangements, and load-bearing systems are thoroughly examined. Material properties and connection details are analyzed for compliance with current regulations.

Material and Reinforcement Detection

Surface inspections, such as scanning and stripping, are conducted to assess concrete quality and reinforcement placement, with core samples taken for laboratory testing.

Risk Mapping and Determining the Need for Strengthening

The building’s earthquake performance is calculated using linear or nonlinear analysis methods like equivalent earthquake load, modal analysis, pushover methods as per Turkish Building Earthquake Code. Vulnerable elements are identified, and a risk map is created.

Determining Strengthening Methods

Methods are selected based on weak points. Different strengthening methods may be applied depending on the structure, such as adding shear walls, jacketing columns and beams, using steel or fiber-reinforced polymer FRP wrapping, or foundation strengthening.

Selection of Appropriate Elements, Design, and Compatibility with the Structure

Cost-effective elements compatible with the structure are chosen. Capacity calculations are performed per Turkish Building Earthquake Code rules, applying knowledge level coefficients.

Project Delivery and Implementation

Calculations, drawings, and reports are finalized. Permits are obtained from the relevant municipality or ministry, and the process is completed with construction supervision.

Importance of Structural Strengthening Projects

Structural strengthening projects are critical, especially in earthquake-prone countries like Turkey, to prevent loss of life and property. Strengthening offers a more economical and faster solution compared to demolishing and rebuilding, as it enhances a building’s earthquake resistance, reduces collapse risks, lowers social and environmental costs, and most importantly, helps minimize loss of life. Pre-earthquake strengthening is more effective than post-disaster repairs, extending the building’s lifespan and ensuring community safety.