二次受火后混凝土强度变化规律的试验研究  

Experimental study about strength change law of concrete after secondary fire

作　　者：史贵臣 张骞尹 杨帆[3] Shi Guichen;Zhang Qianyin;Yang Fan(Hebei TOP Architectural Co.,Ltd.,Shanxi Branch,Taiyuan 030006,China;Wanjingyuan Real Estate Development Co.,Ltd.in Shanxi,Taiyuan 030000,China;China University of Mining and Technology,Xuzhou 221116,China)

机构地区：[1]河北拓朴建筑设计有限公司山西分公司,山西太原030006 [2]山西万景源房地产开发有限责任公司,山西太原030000 [3]中国矿业大学,江苏徐州221116

出　　处：《山西建筑》2022年第7期95-98,共4页Shanxi Architecture

摘　　要：为了研究二次受火后双掺粉煤灰和矿粉的混凝土残余抗压强度及质量损失的变化规律,共设计了13组试验,考虑常温,100℃,300℃,500℃四个温度,分析了一次、二次受火温度及受火顺序对双掺混凝土质量损失率、破坏形态和残余抗压强度的影响。研究结果表明,混凝土二次受火后质量损失率随一次受火温度升高而降低,二次受火温度较高时,降低幅度较明显;混凝土残余强度随二次受火温度的升高而递减,但一次受火500℃后,二次受火时强度递减幅度平缓;提出了二次受火后混凝土残余强度的计算公式,公式简单,适用性高。In order to study change law of residual compressive strength and mass loss of concrete double mixed with fly ash and mineral powder after secondary fire, thirteen groups of experiments were designed, considering the four temperatures of room temperature, 100 ℃, 300 ℃ and 500 ℃, and the influences of the temperature of primary and secondary fire and the fire sequence on the mass loss rate, failure mode and residual compressive strength of double mixture concrete were analyzed. The research results show that the secondary fire concrete quality loss rate decreases with the increase of the primary fire temperature, when the temperature of the secondary fire is high, the reduction is more obvious;the residual strength of concrete decreases with the increase of secondary fire temperature, however, after 500 ℃ of primary fire, the intensity decreases very gently in secondary fire;a formula for calculating the residual strength of concrete after secondary fire is proposed, with simple and high applicability.

关 键 词：二次受火 双掺混凝土 质量损失率 残余抗压强度 

分 类 号：TU528[建筑科学—建筑技术科学]