Fast and effective Define engineering techniques that give weak buildings resistance against earthquakes

Demolishing and rebuilding a building is often very expensive, so building strengthening techniques are considered a less inconvenient, costly and faster alternative to slightly or moderately damaged buildings, as the building's durability and resistance increases thanks to the engineering improvements that are made.

After the storm of earthquakes that struck the cities of southern Turkey and caused heavy losses in lives and property, many began to wonder if their buildings that were built before 1999 (when strict standards were imposed for the construction of earthquake-resistant buildings after the Marmara earthquake) are sufficiently resistant to earthquakes, and how to strengthen the weak ones.

The process of strengthening and strengthening weak buildings aims to give building materials, structural elements or building systems additional strength, making them more resistant to earthquakes, to prevent the loss of life that would occur with the collapse of a building in a possible earthquake. This process helps make the building stronger and more resilient during earthquakes and other disasters.

The demolition of the building and its rebuilding is often very expensive and takes a long time. Therefore, building strengthening techniques are considered a less disturbing, costly and shorter alternative to slightly or moderately damaged buildings, or those built in old traditional ways without taking into account seismic resistance, as the durability and resistance of the building increases thanks to Engineering improvements, as the building and the land on which it is built are evaluated by engineering teams whose task is to determine whether the building is suitable for reinforcement and strengthening.

Examination and evaluation work

Building strengthening companies use a variety of technologies to make homes or workplaces more earthquake-resistant. However, some measures must be taken before strengthening works. First of all, it is checked whether the building to be reinforced was built in accordance with the pre-established engineering design.

Then a seismic ground survey is prepared to find out the current condition of the ground where the building is located. A survey of the building is carried out under the leadership of expert engineers and using an X-ray machine, where the numbers and diameters of the reinforcing steel used in the structural elements of the structure are checked. Sometimes some of the load-bearing elements are stripped to check for corrosion and weakness of the reinforcing steel.

Concrete samples are also taken from the building in sufficient numbers and from the necessary places, and then the samples taken from the building are tested in the laboratory and the current strength of the concrete is determined.

How is construction reinforced?

To prepare the final report that will determine the best methods of strengthening and reinforcement, the building is designed and structurally modeled on computer programs to examine its condition under different earthquake loads. The most important criterion in stiffening work is the correct application. Otherwise, if a wrong method is applied to the building to be strengthened, the building may become more vulnerable to earthquakes.

Based on the findings of the experts' report, and in consultation with the building's owners and residents, the techniques to be used to strengthen the building are determined. After preparing the project, the necessary permits and licenses are obtained from the necessary places to start the strengthening works.

While the technology of strengthening reinforced concrete buildings is widely used due to its low cost, the method of strengthening with steel can be applied, in addition to carbon fiber reinforced technologies, which are an effective method of strengthening old structures.

Here are the most popular strengthening techniques:

Reinforced concrete casings

Reinforced concrete covers

Concrete casing is probably the most widely used method for strengthening members of concrete structures. It is built either with poured concrete in many cases, or with shotcrete. The method includes adding a layer of concrete in the form of a casing over the reinforcing steel network that surrounds the parts to be strengthened such as bases, columns and beams.

Building new concrete walls

Building new concrete walls

This method consists of erecting new walls of large dimensions at selected locations around the building and/or inside the building. Walls can have a very beneficial effect on the seismic performance of existing buildings, simultaneously providing a significant increase in strength, rigidity and ductility.

Steel Props

Steel Props

Steel backing provides similar benefits to building new walls, adding to the strength, rigidity and ductility of the building. Props are bolted directly to the concrete frame, inside or out, to strengthen the main structure. This method contributes to the lateral resistance of the structure through the axial force that develops in its inclined members.

Damping Devices

Damping Devices

Damping devices are used to reduce the amplitude of vibrations and deformations, and thus the stress imposed on structural members by dissipating energy during large earthquake events. Most damping systems can be easily integrated with steel supports, providing strength, stiffness, ductility and greater energy dissipation.

Reinforced Carbon Fiber

Carbon fiber is a much stronger and lighter material than metal. Prepared from high tensile fibers within a polymer matrix such as epoxy plastic, vinylester or thermoplastic polyester, but most commonly epoxy resin. These threads are then woven into fabrics less than a millimeter thick. Although the carbon fiber structure is five times lighter than steel, it is known to be more resistant.

Reinforced Carbon Fiber

Because of its high tensile strength and low weight compared to traditional structural materials, particularly steel, carbon fiber has become an important structural material for use in the construction industry as frequent internal or external reinforcement.

This method relies on wrapping carbon fibers by gluing them to parts of the concrete structure, which gives walls, columns and beams increased durability in the event of an earthquake. The occurrence of severe building collapses in the event of an aftershock after an earthquake is greatly reduced.

Steel Casings

Steel Casings

Single steel plates or strips bonded to concrete members can improve bending strength, similar to carbon fiber reinforced strips. Similarly, plates, strips and angles welded together to form a casing can increase the shear strength tolerance and greatly improve the behavior of structural parts during an earthquake.