Measuring Three-Dimensional Temperature Distributions in Steel-Concrete Composite Slabs Subjected to Fire Using...

Area of Science:

• Structural Engineering
• Fire Safety Engineering
• Materials Science

Background:

• Understanding temperature distribution is critical for assessing structural behavior under fire conditions.
• Steel-concrete composite slabs are widely used in construction, necessitating accurate fire performance evaluation.
• Existing methods may not capture the complex, non-uniform thermal responses within these structures.

Purpose of the Study:

• To develop and validate a method for imaging 3D temperature distributions in steel-concrete composite slabs during fire exposure.
• To assess the feasibility and accuracy of using distributed fiber optic sensors for this purpose.
• To highlight the importance of high-density, through-depth temperature data for structural fire analysis.

Main Methods:

• Development of a novel imaging technique utilizing distributed fiber optic sensors.
• Experimental investigation on six steel-concrete composite slab specimens (1.2 m × 0.9 m).
• Fire exposure tests conducted for over 3 hours, with simultaneous measurements from distributed sensors and thermocouples.

Main Results:

• Distributed fiber optic sensors successfully measured dense point clouds of temperature up to 960 °C.
• The sensors demonstrated acceptable accuracy for structural fire applications.
• Measured non-uniform temperature distributions confirmed the spatially distributed thermal response of the slabs.

Conclusions:

• The developed method effectively images 3D temperature distributions in steel-concrete composite slabs under fire.
• Distributed fiber optic sensors are a viable tool for accurate, high-density temperature monitoring in fire engineering.
• High-density through-depth temperature data is essential for adequately capturing the thermal behavior of composite slabs in fire.