空腔陶粒混凝土墙板耐火性能研究OA北大核心CSTPCD

To investigate the fire performance of hollow-cavity ceramsite concrete wallboards(HCCCW),this study conducted one-sided fire tests on four HCCCWs.The experiment yielded results on their thermal response,fire resistance,and out-of-plane deformation,providing insights into the heat transfer mechanism of HCCCWs under one-sided fire exposure.An analysis of the distribution characteristics of section temperature fields and temperature gradients was performed by establishing finite element models.Based on the validated models,parametric studies were conducted on hollow-cavity area,volume-cavity ratio,ceramsite concrete density,and type of filling material.The results indicate that as the volume-cavity ratio increases from 23.55％to 35.00％,the duration of steam escape from the unexposed surface decreases by 43.75％and the number of cracks on the fire-exposed surface decreases by 58.97％.In the temperature-time curve for the unexposed surface of HCCCW,both the duration of heat front propagation and the temperature plateau increase with the decrease in volumetric cavity ratio and cavity wall area.Compared with heat conduction in ceramsite concrete,cavity radiation significantly improves heat transfer efficiency.Additionally,the temperature at the center of the cavity is approximately 20％higher than that at its midpoint along with webbing.Decreasing hollow-cavity area and volume-cavity ratio or increasing ceramsite concrete density effectively enhances the fire performance of HCCCW.Considering structural weight,material cost and fire resistance,filling cavities with rockwool is proven to be most cost-effective.