【摘要】 500 MPa细晶粒热轧带肋钢筋(HRBF500)强度高、延性好,是一种新型材料。为使其应用得到推广,通过明火试验,考察ISO 834标准升温曲线下,HRBF500级细晶粒钢筋混凝土(RC)梁的火灾行为;采用ANSYS分析和研究高温下细晶粒混凝土梁截面内的瞬态温度分布,并与试验结果对比;对4根细晶粒钢筋混凝土梁,在经历不同的受火时间后自然冷却至室温,进行振动测试,分析混凝土梁自振频率受高温作用的影响规律。研究得到,细晶粒钢筋混凝土梁在受火后的自振频率随着受火时间的增长而不断减小;梁的配筋率越小,自振频率减小的幅度越大。更多还原

【Abstract】 The hot rolled bar of fine grains 500 MPa is a new material which has high strength and good ductility.For promoting its application,through the flame test,the fire behavior of HRBF500 reinforced concrete beams was studied in fire,under the ISO834 standard fire curve.Considering the thermal properties of concrete and using ANSYS program,the transient temperature distribution within the cross-section of the concrete beams was studied at the high temperatures and the data were compared and analyzed with the experimental results.It was also conducted the vibrator test of four fine grain reinforced concrete beams after fire to study their dynamic properties.With different time under fire and when the beams were cooled to room temperature naturally,their self-resonant frequencies were investigated through the vibrator test.The results show that the self-resonant frequency of concrete beam is seriously affected by fire.Some conclusions are drawn out: The longer it is exposed to fire,the smaller is its self-resonant frequency.And also,the smaller is bar ratio,the bigger is its self-resonant frequency.更多还原