Nonlinear Analysis of Time-dependent Effect for Reinforced Concrete Thin-wall Box Girders Exposed to Fire

Aimed for fire-resistant performance for reinforced concrete thin-wall box girders, the energy equation and compound boundaries conditions were created. Analyses were performed to study the time-dependent laws of deflection for reinforced concrete thin-wall box girders exposed to fire． The results indicate that the vertical-deformation ability of reinforced concrete thin-wall box girders effectively increases with the increment of concrete cover thickness. The vertical-deformation presents a nonlinear increasing trend with the increment of extending-fire time.