A Method for Instant Estimation of the Temperature Experienced by Fire-Damaged Reinforced Concrete Structures Using...

Area of Science:

• Materials Science
• Civil Engineering
• Structural Engineering

Background:

• Fire exposure compromises concrete structure safety and durability through spalling, scaling, and chemical changes like dehydration of Ca(OH)2 and rehydration of CaO.
• Rapid diagnosis and evaluation techniques are essential for timely repair and reinforcement of fire-damaged reinforced concrete (RC) buildings.
• Quantitatively determining the maximum heating temperature is a crucial step in assessing fire damage to RC structures.

Purpose of the Study:

• To demonstrate a reliable method for estimating the heating temperature experienced by fire-damaged RC buildings.
• To develop a technique for rapid, accurate, and simple temperature assessment based on material properties.

Main Methods:

• Two short RC column specimens were prepared with embedded titanium strips.
• The discoloration characteristics of titanium at elevated temperatures were analyzed to estimate heating temperatures.
• Empirical equations were derived correlating titanium discoloration with temperature based on depth.
• Thermocouples were used to measure the actual heating temperature for comparison.

Main Results:

• Titanium strip discoloration provided a quick, accurate, and simple mechanism for estimating heating temperature by depth.
• Derived empirical equations effectively estimated heating temperatures based on titanium's visual changes.
• The proposed method showed an average error of less than 20 °C compared to thermocouple measurements.
• A significantly good correlation and extremely high reliability were demonstrated for the developed method.

Conclusions:

• The study successfully demonstrated a reliable method for estimating fire-induced heating temperatures in RC structures using titanium strips.
• The technique offers a practical solution for rapid assessment of fire-damaged buildings, facilitating informed repair and reinforcement decisions.
• The high accuracy and reliability of the method make it a valuable tool for structural engineers and building safety professionals.