公路隧道衬砌混凝土火灾高温下的物理力学损伤规律

围绕公路隧道衬砌混凝土火灾高温下的物理力学损伤特征,通过大量的公路隧道衬砌混凝土试件烧蚀试验,及试件烧蚀后的探伤试验（超声波法、回弹法）、强度试验和刚度试验,系统研究国内公路隧道C20～C35常用混凝土标号区间的混凝土材料火灾损伤,给出各种工况下的损伤规律与表现特征。对公路隧道衬砌结构温度损伤形式进行划分,对混凝土材料的火灾后力学性能进行归纳分析,建立衬砌混凝土外观和力学指标与火灾温度的定性、定量关系,总结提出衬砌混凝土损伤等级,为定量与定性评价公路隧道衬砌混凝土损伤状况提供试验依据。

Rules of Physical and Mechanical Damages of High Temperature of Fire to Lining Concrete in Highway Tunnels

In accordance with the features of physical and mechanical damages of high temperature of fire to lining concrete in highway tunnels and based on ablation test for specimens of lining concrete in highway tunnels,flaw detection tests（ultrasonic test and rebound method） after ablation of specimens,strength test and rigidity test,this paper systematically studies and analyzes fire damages to materials of concrete at the grades of C20～C35 commonly used for domestic highway tunnels and presents rules and characteristics of damages under various working conditions.The paper classifies the forms of temperature damages to lining structures of highway tunnels,carries out inductive analysis for mechanical properties of concrete materials after fire,establishes qualitative and quantitative relations between appearance and mechanical indicators of lining concrete and fire temperature,and concludes class of damages to lining concrete so as to provide test bases for qualitative and quantitative evaluation of damage status of lining concrete in highway tunnels.