Reduced-order modeling of composite slabs in fire. II: Thermal-structural analysis.

Area of Science:

• Civil Engineering
• Materials Science
• Structural Fire Engineering

Background:

• Composite slabs with profiled steel decking are common building components.
• Understanding their behavior under fire conditions is crucial for structural safety.
• Existing models may be computationally intensive or lack comprehensive analysis.

Purpose of the Study:

• To develop and validate a reduced-order modeling approach for thermal and structural analysis of composite slabs under fire.
• To enable efficient and accurate simulation of fire effects on these structures.
• To investigate the influence of steel decking and reinforcement placement on structural response.

Main Methods:

• Utilized alternating strips of layered shell elements to represent slab geometry.
• Integrated thermal and structural analyses into a single model.
• Validated the approach against experimental data from ambient and fire tests on one-way and two-way composite slabs.
• Evaluated implicit and explicit solution schemes for structural analysis.

Main Results:

• The reduced-order model accurately captures the behavior of composite slabs under fire.
• Explicit dynamic analysis allows for significant reduction in simulation time (hours to seconds) without accuracy loss.
• Steel decking's contribution to resistance diminishes rapidly under fire.
• Reinforcement location significantly impacts structural response due to differential heating.

Conclusions:

• The developed reduced-order modeling approach is effective for analyzing fire effects on composite slabs.
• The method offers a computationally efficient alternative for structural fire design and assessment.
• Accurate modeling of thermal effects and reinforcement placement is vital for predicting structural performance under fire.