Steel Plane Staggered Truss Fire-resistant Performance Analysis And Software Development

As a novel system of steel structure, the steel staggered-truss framing system (SSTFS) has been analyzed theoretically and applied into some projects abroad. Recently, the Chinese government is also popularizing the application of this system actively. Building fire is an important factor affectting the performance of the overall security of steel buildings. How to consider the fire-resistant performance of the SSTFS under fire conditions and obtain its limit fire-resistance temperature are especially important for promoting the application of the system. However, at present, the research on fire-resistant properties of the SSTFS is still in its infancy. Supported by the Science and Technical Research Foundation of Ministry of Education (No. 50706059), in this thesis, the structural response of SSTFS under fire conditions was studied, which is aiming at offering convicting evidence for the popularizing of the system.The following works have been fulfilled within this thesis:(1) The classification of the potential fire model of SSTFS in the cases of the whole floor exposing to fire was done.(2) According to the structural characteristics of SSTFS, a simplified thermo-mechanical coupled analysis method was puted forward based on the ANSYS software, and it was validated by compared with the traditional ANSYS thermo-mechanical coupled analysis method, the results show that the simplified analysis method has good accuracy, and it is suitable for the batch analysis.(3) It is the first time that the numerical simulation of the whole elastic-plastic structural response process of SSTFS under fire was conducted, by using the simplified method. The law of the mechanic response of the structure from the fire occurred to structure destroyed was obtained, and the influence on the limited fire-resistant temperature of some variables was presented.(4) The mechanic response of SSTFS under fire conditions concerning the lateral loads was analysed, the affection of the lateral force on the fire-resistant perfomance was studied, and the fire response behaviour was discussed under different lateral forces.(5) Combining Visual Basic with the ANSYS secondary development language APDL, the professional software FRASST1.0 was developed, which aim at the fire-resistance analysis of the SSTFS , and increasing work efficiency.