Reinforced Concrete Strengthening

Reinforced Concrete Strengthening

Reinforced concrete strengthening comprises the works carried out to increase the durability of existing reinforced concrete structures and to minimise the risks arising from damage. This work raises the load-carrying capacity of structures and makes them safe against natural disasters. Reinforced concrete strengthening is tailored on the basis of the technical analysis of the structure and requires an approach specific to each building.

Reinforced concrete structures that have lost their structural integrity over time under the effect of natural disasters such as earthquakes are made sound and durable again through strengthening works. The modern methods and materials used in the strengthening process give structures a long life.

Advantages of Reinforced Concrete Strengthening:

• Increased Durability: Ensures safety by increasing the load-carrying capacity of the structure.
• Damage Prevention: Makes good existing damage and prevents problems that could arise in the future.
• Tailored Solutions: Effective results are obtained with methods suited to the characteristics of the structure.
• Long-Lasting Structures: Extends the service life of structures and increases their economic value.
• Earthquake Resistance: Enables the structure to gain resistance to earthquakes.

The Reinforced Concrete Strengthening Process:

1. Analysis and Assessment: The current condition of the structure is analysed and the strengthening requirements are determined.
2. Selection of Method: Strengthening techniques and materials specific to the structure are selected.
3. Application: The strengthening work is carried out by professional teams using the most suitable methods.
4. Testing and Inspection: The work is verified by tests and inspections after strengthening.

With its expert team and modern technologies in the field of reinforced concrete strengthening, Likit İzolasyon makes your structures safe and durable. With our professional solutions we restore your structures to a sound and dependable condition.

Application Areas of Reinforced Concrete Strengthening

• Residential and commercial buildings found to have inadequate seismic performance
• Structures where an additional storey or a change of use is planned
• Reinforced concrete systems where inadequate section sizes have been identified in columns and beams
• Buildings with a soft storey or torsional irregularity
• Structures damaged after an earthquake for which a repair and strengthening decision has been taken

Reinforced Concrete Strengthening Techniques

Column and Beam Jacketing

New reinforcement, connected by dowelling, is placed around the existing element and concrete is poured to enlarge the section. The element gains both flexural and shear capacity. Because the section grows, floor area is lost in the architectural plan; this must be considered at the design stage.

Adding Reinforced Concrete Shear Walls

By adding new shear walls to the structure, the lateral load capacity and stiffness are increased markedly. This is the method that improves seismic performance most effectively. Foundation reinforcement is often necessary so that the wall's loads can be transferred properly to the foundation.

Slab and Foundation Reinforcement

Slabs and foundations whose capacity has become inadequate because of new loads or added shear walls are strengthened. Widening, thickening or mini-pile applications may be preferred at the foundation.

The Application Process

• 1. Survey of the existing structure: A measured survey is produced; element dimensions are measured, the reinforcement layout is determined with a scanner, and the concrete strength is established by coring.
• 2. Performance analysis: The structure is modelled and assessed in accordance with the current seismic code; inadequate elements and the target performance are determined.
• 3. Design and approval: The strengthening design is prepared, the sequence of works and the details are devised, and the approval of the competent authority is obtained.
• 4. Surface preparation and dowelling: The existing concrete surface is roughened and the cover is removed. Holes are drilled and cleaned and dowels are installed with chemical anchors.
• 5. Reinforcement, formwork and concrete: The new reinforcement is tied, the formwork is erected, and concrete of the appropriate class is poured and compacted with a vibrator. Curing is applied.
• 6. Inspection and reporting: A works file is compiled with anchor pull-out test results, concrete sample results and photographs of the works.

Technical Notes and Standards

• The assessment and strengthening of existing buildings is carried out in accordance with the provisions of the TBDY 2018 .
• For reinforced concrete design rules, TS 500 is taken as the basis.
• The bond between the new concrete and the existing concrete depends directly on the roughening of the surface and the spacing of the dowels.
• In jacketing, the increase in section size affects the architectural and services designs; coordination is essential.
• The sequence of the strengthening works matters; phasing must be planned so that the structure is not temporarily weakened.

Frequently Asked Questions

Which is more effective, jacketing or adding shear walls?

Jacketing increases capacity element by element, whereas adding shear walls raises the lateral stiffness and strength of the structure as a whole. If there is general inadequacy and excessive drift in the structure, adding shear walls is more effective. The decision is made on the basis of the performance analysis.

Does strengthening increase the value of the building?

A structure whose seismic safety is documented is an advantage in terms of sale, purchase and insurance. Beyond that, the real gain is safety of life. The work being designed and approved is necessary for this value to be capable of documentation.

Is refurbishment needed inside the flats?

Jacketing and adding shear walls create an increase in section size inside the property; plastering, painting and sometimes renewal of the services are required. The scope varies with the design. For this reason strengthening is often planned together with a general refurbishment.

Can it be carried out while the building is occupied?

Phased working may be possible in works of limited scope. However, in extensive works such as adding shear walls and reinforcing foundations, evacuation is required because of dust, noise, breaking out and occupational safety. The decision is made according to the scope of the project.