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This paper investigates the post-fire seismic performance of steel reinforced concrete (SRC) beam to SRC column frames. Five SRC column to SRC beam planar frame specimens were tested in a program including a loaded fire test and a following horizontal cyclic loading test. Test parameters included heating time and column load ratio. The temperature development, deformation, post-fire hysteretic and skeleton curves, stiffness, ductility and damping coefficient of SRC frames are recorded, calculated and analyzed. The measured post-fire hysteretic curves indicates that the SRC frames exhibit very good energy dissipation capacity after fire exposure. The horizontal load capacity and viscous damping coefficient of SRC frames increase with the increase of column load ratio. However, column load ratio has an adverse influence on ductility as anticipated at normal temperature. One SRC frame specimen failed during the cooling phase, which demonstrates the importance of considering the cooling phase during the fire safety design.

This paper presents an experiment study of the post-fire behavior of five SRC columns under combination of axial eccentrical loading and fire. The experiment phenomena and mechanical response of the SRC column specimens during experiment, specifically loading, heating, cooling and post-fire loading were observed. The residual load bearing capacity, failure modes and vertical deformation were studied. With the test program, the effects of parameters such as the load ratio, the fire duration time and the steel ratio were studied. It is shown that the effects of temperature delay become more obvious with the increase of the depth from the heated surface. Some of the SRC column specimens failed during the cooling phase. For other specimens residual deformations were observed when the furnace temperature decreased to ambient temperature. The influence of some parameters including the load ratio, the fire duration time and the steel ratio on the post-fire load bearing capacities was discussed. It can be concluded that the residual load bearing capacity of the SRC columns decreases with the increase of the fire duration time and the load ratio, and increases with the increase of the steel ratio. Finally, a finite-element analysis model was developed to simulate the behavior of the tested SRC columns.

A fire performance finite element (FE) model of space grid structures in fire and after fire is proposed, and deformation, stress redistribution, failure modes of grid structures are also studied. The result shows that tensile membrane action arises when the grid is loaded after fire, and the load bearing capacity after fire is reduced by fire damage.

A heat transfer finite element model for the temperature analysis of space grid structures considering the conduction and protection thickness of the steel members in fire is proposed, and the temperature field of a typical grid structure is analyzed by using the proposed model. The results show that the proposed model is reasonable.

The anti-explosion effects and anchored mechanism of tunnels reinforced by bolts were studied by numerical analysis. Comparing with compression-stress curve of the experiments and numerical simulation on the same location of the vault, it indicates that the simulation results are reliable. By contrast the vault displacement of anchored tunnel and unlined tunnel, it can be found that the vault displacement of the tunnel is significantly reduced through the reinforcement with anchor bolts. By comparing the crack distribution of the anchor tunnel and unlined tunnel, it shows that cracks of unlined tunnel are significantly thicker and wider than that of the anchored tunnel, which indicates that the anti-explosion effects of anchor rods are better. It can be known that the anchored bolts supporting can take effect of reinforcement and anti-explosion according to the time-histories curve of the anchor-head.

Failure mechanism and fire resistance comparison of concrete-filled steel tube (CFST) frames, reinforced concrete (RC) frames and steel reinforced concrete (SRC) fames are proposed in this paper when their bearing capacity and rigidity at room temperature are similar. The result shows that the failure mode and failure mechanism of the 3 frame structures are much different, and the SRC frames have the maximum fire resistance.

An experimental study on the fire performance of reinforcing concrete beam-column joints under ISO834 standard temperature-time curve was carried out, and the main parameters including the load ratio of the beams and axial compression ratio of the columns were chosen to study the performance of the joints. The deformation, the explosive spalling of concrete, the fire resistance and the collapse mechanism of the joints in fire are observed carefully, and several conclusions are drawn in the end.