Estimation of Concrete Strength Using the Maturity Method

Estimation of Concrete Strength Using the Maturity Method

The maturity method is an advanced methodology used to estimate concrete strength accurately, based on temperature and curing time. At Obralink, we are leaders in the application of this technology, supported by a deep understanding of international standards, such as ASTM C1074, NCh 3565:2018 (in the case of Chile), and NMX-C-219-ONNCCE-2005 (in the case of Mexico). Using Rsense2, an innovative device developed by Obralink, we can continuously and accurately monitor the concrete's maturity, ensuring the information obtained is reliable and suitable for critical decision-making on-site.

Maturity Method for Strength Estimation

The maturity method is based on the principle that concrete strength is influenced by the combination of temperature and time. This methodology allows strength prediction without the need for destructive testing, providing an efficient and safe alternative for quality control in the construction process. Maturity is defined through two main approaches: the temperature-time factor and the equivalent age at a specific temperature. Both methodologies are covered by ASTM C1074, which serves as the technical basis for this method.

To perform an accurate estimation of strength, it is essential to develop a specific maturity-strength relationship in the laboratory for the concrete mix used in each project. The Rsense2 device from Obralink is key to this process, as it allows for continuous recording of concrete temperature and calculation of the maturity index, which is fundamental for on-site strength estimation. This device, developed in-house by Obralink, is a significant advancement in concrete monitoring technology, offering a precise and effective solution.

ASTM C1074 and NCh 3565:2018 Standards

ASTM C1074 is the international reference standard that establishes guidelines for the maturity method, based on the relationship between temperature, curing time, and strength. According to this standard, the maturity index is calculated by accumulating the product of temperature and curing time of the concrete. This standard is widely used in North America and has become a global standard for on-site strength estimation.

Chile’s NCh 3565:2018 is also a crucial standard that defines how to implement the maturity method in local projects. The Chilean standard establishes a procedure for determining concrete maturity using the Nurse-Saul model, which is the same fundamental model as in ASTM C1074. The rigorous application of this standard ensures concrete quality, minimizes risks, and guarantees the success of construction projects.

Rsense2 Technology and PT100 Temperature Sensor

The Rsense2 is an advanced device designed by Obralink to measure concrete maturity, being a sophisticated and innovative system that provides accurate and real-time information.

Integration with PT100 Temperature Sensors

This device integrates with PT100 temperature sensors, which are high-quality platinum resistance sensors, widely recognized for their precision and stability.

Main Features of Rsense2 and PT100 Sensors

• Measurement Range: Temperature from -50°C to 500°C.
• Fast Response: Response time of 0.1 seconds, critical for accurate measurements during the initial curing stages of concrete.
• Thin-Film Construction: Ensures a high degree of accuracy and superior resistance to vibrations and harsh job site conditions.
• LoRa Technology: Low-power, long-range wireless communication, ideal for industrial environments.

LoRa Technology

The Rsense2 utilizes LoRa technology for wireless transmission of temperature data, automatically sending it every 15 minutes to our LoRa receiver, corresponding to our patented Cibot devices.

LoRa (Long Range) is a low-power, long-range wireless communication technology, ideal for industrial environments where data transmission over long distances is required without cables. This technology ensures that data collection is carried out efficiently and without interruptions, which is fundamental for continuous concrete curing monitoring.

Benefits of the Technology

Thanks to this technology, our solution does not require human intervention, enabling constant and accurate monitoring, reducing the possibility of errors, and optimizing the construction process.

Implementation of the Maturity Method in Construction Projects

At Obralink, the implementation of the maturity method is carried out rigorously, following ASTM C1074, NCh 3565:2018, and NMX-C-219-ONNCCE-2005 standards.  
Thanks to Rsense2, we are able to record concrete temperature in real time and calculate the maturity index with high accuracy.

All the information collected by our Rsense2 devices is measured, integrated, and precisely processed in our web systems, including our BIM platform, which integrates all the information clearly and in real time for all our clients.  
This allows our clients to accurately determine the optimal timing to carry out critical actions, such as formwork removal, opening structures to vehicle traffic, or post-tensioning tendons.

Integration into the Obralink Web Platform

The application of the maturity method ensures that decisions made during the construction process are based on reliable, high-quality data.  
This minimizes risks, optimizes execution times, and ensures that the concrete used meets the specified structural requirements.

One of the great values of Rsense2 is precisely its ability to indicate to clients the exact moments for formwork removal, opening structures, or post-tensioning, significantly contributing to the efficiency and safety of projects.

Why Use the Maturity Method and Rsense2 Sensors?

• Accelerate Formwork Removal: The maturity method determines the optimal time for formwork removal, which helps speed up the construction process without compromising the quality and safety of the structure.
• Early Post-Tensioning: In post-tensioned projects, it is crucial to know the precise time to perform tendon post-tensioning. With the maturity method and Rsense2 sensors, this operation can be carried out at the optimal time, ensuring structural integrity.
• Measure Strength in Monolithic Formwork Projects: In projects that use monolithic formwork, the maturity method is essential to measure the concrete strength before removing the formwork. This automatic monitoring capability reduces worker intervention in the process, which helps reduce labor hours in strength measurement, increasing project efficiency and safety.

Conclusion

The maturity method is an essential tool in modern construction to ensure the quality and strength of concrete.  
At Obralink, we are experts in applying this methodology, using advanced technology such as Rsense2 and PT100 sensors to record temperature data and accurately calculate the maturity index.

Supported by standards such as ASTM C1074, NCh 3565:2018, and NMX-C-219-ONNCCE-2005, we guarantee our clients reliable and efficient solutions that contribute to the success of their construction projects.

At Obralink, our commitment is to offer cutting-edge technology and the best technical knowledge, ensuring that each stage of the construction process is safe, efficient, and meets the highest quality standards.