ETRI WEBZINE

VOL.69 July 2022

FOCUS ON ICT

ETRI developed a monitoring
system which predicts the curing
quality of concrete

- Prevent the accident of building collapse with the optical fiber sensors and
AIoT fusion technology

A research team of The Electronics and telecommunications research institute (ETRI) is in the process of developing a technology that can estimate the concrete strength in advance by planting optical fiber sensors inside when pouring concrete to build a building. This technology will be widely applied not only to buildings, but also to dams, oil pipes, underground water pipes, and etc., and it is expected to protect people’s lives and safety.

The research team is focusing on predicting the building collapse accidents. The team has developed an Intelligent monitoring system for building safety by the fusion of optical fiber sensors and AIoT¹⁾ technology. The goal²⁾ is to lower the accident rate in the construction industry to less than 0.5%, which is the accident rate in the general industries.

The technology developed by ETRI is 『Optics-based SSHM system³⁾』. Optics-based SSHM system can estimate the long-term strength of concrete early by considering the hydration heat⁴⁾ generated during concrete curing, concrete mixing ratio, external environment. It is possible to prevent collapse at the construction process by predicting concrete strength. After construction, the optics-based SSHM system can monitor the condition of a building at all times using optical fiber sensors that can measure temperature, tensile force, torsion, vibration, etc.

Currently, the research team is monitoring the hydration Heat of concrete maturity in winter by building a prototype and testbed for the evaluation of system's applicability to construction sites.

Moreover, the research team announced that the algorithm for predicting the curing quality and long-term strength of concrete will be applied to the system.

The research team monitors building cracks, etc., through sensing after inserting the optical fiber of 1mm diameter per the unit area (3m x 3m) of concrete. The sensor inside concrete can be used semi-permanently. In the case of the 100㎡ APT, more than 20 sensors are required.

The optics-based SSHM system is about the size of a laptop computer and can check data collected from the optical fiber sensor such as temperature, material strain, vibration measurements, etc.

ETRI explained that the point of this technology is “Sensing technology based on optical fiber which can be expanded to various applied technologies such as crack trend monitoring, external noise measurement, as well as predicting long-term strength.”

In the future, the research team plans to improve the integrity of technology by developing AI deep-learning technologies that meet customized demands of the construction company, such as concrete mixing ratios. In addition, the system will be applied to construction sites to predict the formwork removal time, concrete deterioration, and building lifecycle monitoring.

Gilhaeng Lee, head of the ETRI Honam Research Center, said, “We will use ICT to reduce casualties caused by collapse of concrete slabs, poor installation of concrete, and shortening construction period when remoning the mold at construction sites where major disasters occur ever year.”

This technology is planned to be commercialized by transferring the technology to construction and safety companies.

In addition, the research team plans to implement the monitoring system that predicts the curing quality of concrete at construction sites with Gwangju Metropolitan City at South Korea.