| Due to its high strength and high durability,high strength concrete(HSC)has been more and more widely used in today’s building structures.However,due to the deterioration of material properties and the spalling of high-strength concrete at high temperatures,HSC components have certain safety hazards under fire.As an important load-bearing member and horizontal partition member of the building structure,the slab’s fire resistance plays an important role in the overall fire safety of the structure.Therefore,the analysis of fire resistance performance of HSC slabs has important engineering significance for the fire safety of building structures and the promotion and application of HSC,In view of the lack of research on the fire resistance of HSC slabs,in this thesis,based on the validation of the non-linear finite element analysis model by the experiments reported in the literature,the temperature field and mechanical response of HSC one-way slabs and two-way slabs under fire condition are analyzed and the influence of different factors on the fire resistance of HSC slabs are numerically studied.The main contents of the thesis are as follows:(1)The numerical model used for the thermo-mechanical analysis of HSC slabs is validated by the experiments reported in the literature.By comparing the numerical results and the experimental results,the effectiveness of the finite element model is verified.(2)The temperature field of HSC one-way and two-way slabs is analyzed,and the influence of different factors on the temperature field and thermal insulation performance of the slabs are studied.Based on the analysis,engineering suggestions are proposed for improve the thermal insulation performance of HSC slabs.(3)The thermo-mechanical response of HSC one-way and two-way slabs under fire condition are numerically analyzed and the fire resistance performance of the slabs are studied.According to the numerical results,engineering suggestions are proposed for the fire resistance of HSC slab.(4)Quantitative analyses of the influence of concrete spalling on the fire resistance of HSC one-way and two-way slabs under different conditions are conducted.Based on the analysis results,some engineering suggestions are given for reducing the impact of spalling on the fire resistance of HSC slabs. |
