It is common knowledge that structural fires have led to a great loss of buildings and damage to property in the past two decades. Therefore, there is a growing need to provide approaches for post-fire repair of structural members to enhance their structural safety. This paper presents a state-of-the-art review on the repair of fire-damaged reinforced concrete (RC) members with axial load. The investigations into the effects of loading method, physical dimension and bonding behavior on the residual strength of members are presented. In the meantime, the available experimental investigations on the performance of fire-damaged RC members with axial load repaired with concrete jacketing, steel jacketing and fiber-reinforced polymer (FRP) jacketing are summarized. Moreover, models for predicting the residual strength of fire- damaged columns are reviewed.

The mechanical properties of both concrete and steel reinforcement, and the load-bearing capacity of reinforced concrete (RC) structures are well known to be temperature-sensitive, as demonstrated by the severe damage that major fires cause in buildings, followed—in extreme cases—by their collapse. Since in most cases RC structures survive a fire, retrofitting fire-damaged RC members is a hot subject today. In this paper, after a recall on the performance of RC beams and slabs in fire, different repair techniques are considered, among them externally bonded reinforcement, near surface-mounted fiber-reinforced polymers (FRP), bolted side plating, jacketing with high- and ultra-high performance concretes or mortars, and damaged-concrete replacement. Last but not least, the design equations aimed at evaluating the residual load-bearing capacity after repairing are also presented and discussed.

This paper introduces simple glued laminated (glulam) timber columns reinforced by near-surface-mounted carbon-fiber-reinforced polymer (CFRP) laminates (GTMC columns). Twenty-four columns were fabricated and tested under eccentric compression loading to validate the effectiveness of this kind of column. In accordance with the degrees of eccentricity, specimens were divided into three groups. In each group, one column without inlaid CFRP laminates served as a control column, while the others were inlaid with CFRP laminates. All columns were tested for ultimate load capacity, displacement ductility, failure mode, and energy dissipation capacity. Test results show that inlaid CFRP laminates are effective in increasing ultimate load capacity and deformability. Meanwhile, the corresponding analytical model was also derived to predict the ultimate load capacity of GTMC columns. A comparison of the predicted and tested ultimate load capacities demonstrated that the analytical model is generally able to ...

Due to the flammability of materials and the vastness of space, flashover fires of large-space timber structures pose a huge threat to lives as well as the structures themselves. Therefore, it is necessary to study the critical conditions, control factors and prediction methods of flashover fires. To address this issue, hundreds of design conditions were simulated by Fire Dynamics Simulator (FDS) with variations in space size, the heat release rate (HRR) of fire source and fire growth type. A temperature–time model of the maximum temperature of the smoke layer near the ceiling (T_max) was established, and the critical condition that uses this model to predict the occurrence of flashover was determined. Furthermore, a mathematical formula was established that can accurately predict the flashover induction time when the T_max exceeds 400 °C. This research can provide a reference for the performance-based fire safety design of large-space timber structures.