Bebek Apartment Structural Reinforcement

A 1985-built, 6-story reinforced-concrete apartment building in Bebek, with two units per floor. As urban transformation projects accelerated in the neighborhood, residents wanted to measure the seismic performance of their own building. The initial inspection reported a "moderate damage risk." Instead of demolition, reinforcement was selected — more economical and faster in time.

The performance analysis took 3 weeks. Concrete core samples were drawn from 12 different points; the average concrete grade came in at C16–C20 — below code. Rebar scanning identified column cross-sections and reported insufficient stirrup density.

A hybrid approach was chosen for reinforcement:

• Carbon fiber (CFRP): precision column and beam reinforcement without losing architectural appearance — preferred inside the apartments
• Steel jacketing: applied to the main load-bearers on the ground floor and basement; more economical and high in strength
• Sprayed concrete (shotcrete): for basement shear walls

This combination could be applied without requiring residents to move out.

The work was carried out floor by floor in sequence. While one floor was worked on, the floors above and below kept their access open; residents lived through the process without leaving their homes. The visible intervention averaged 14 days per floor.

Before carbon-fiber application, every column surface was sanded and an epoxy primer was applied. CFRP strips were applied transversely and longitudinally under factory-certificate control. After plastering, the surfaces returned to their pre-application appearance — residents said, "our columns don't look like they've changed."

On the ground floor, shear walls were thickened with shotcrete and the rebar was re-woven. In the basement, damp shear wall surfaces were dried before water-proofing was redone — the reinforcement doubled as a moisture repair.

After 5 months, the building was delivered with performance exceeding the "Life Safety" target of the DBYBHY 2018 seismic code and approaching the "Immediate Occupancy" level. The building-inspection-approved report was delivered to each owner individually. A "building reinforced" annotation was added to the land registry at the municipality; this annotation will add value at any future sale or rental.