运营期桥梁火灾后结构检测成套技术
Complete structure detection technology of bridge？？after fire in operation period

为了对桥梁结构火灾后的状态进行检测评定，在传统检测方法的基础上，结合火灾事故特点，对结构进行针对性检测与评估，并第一时间评定桥梁承载能力的受损程度，评判其是否影响行车安全。依托典型的实际工程案例进行了较为系统的阐述，具体包括检测方法、监测手段、成果分析、管养建议等。在常规外观检查方法的基础上，采用3D扫描技术对受损结构进行实体建模分析，定量分析病害开展部位及损伤程度，并对混凝土、钢筋等主要材料的劣化部位进行了取样分析，分别在现场和实验室对桥梁受损状况进行了综合性评价；从结构整体姿态角度对桥梁进行跟踪监测，预警火灾损伤对结构安全可能带来的不利影响，进一步保证桥梁后续运营安全；依据现场检测数据及理论分析，对桥梁受损结构温度场、材料退化程度、损伤等级、承载能力等方面进行了分项评定；并从病害维修及后续管养等角度分别提出了较为合理和针对性的处治意见。最后，根据此类项目特点，总结相关技术经验，研究形成了运营期桥梁火灾后结构检测成套技术。研究结果表明：火灾后混凝土强度和钢筋性能的实际劣化程度比规范推定结果要小，应依据实际情况对桥梁承载能力现状进行折减和准确评价；提出的成套技术的有效运用，可在一定程度上提高火灾后结构检测评定的效率和准确性，是现有检测技术和规范的有效补充，该研究为类似事故桥梁的运营管理决策提供了一定的理论依据。
To detect and assess the state of bridge structures after a fire, based on traditional detection methods combined with the characteristics of fire accidents, a structure was targeted for testing and evaluation. The damage degree of bridge bearing capacity was evaluated at the first time, and the effects of judgment on driving safety were evaluated. Based on typical practical engineering cases, a systematic exposition on these topics was presented including detection methods, monitoring methods, results analysis, and management advice. Based on conventional appearance inspection methods, 3D scanning technology was used to analyze the damaged structure. Disease location and damage degree were analyzed quantitatively, sampling and analysis of the deteriorated parts of main materials (such as concrete and steel bars) were conducted. A comprehensive evaluation of bridge damage was performed in the field and laboratory. Tracking and monitoring of bridges from the perspective of structural overall attitude and the adverse effects of early？？warning fire damage on structural safety were studied, to ensure the subsequent operation safety of bridges. Based on field test data and theoretical analysis, the temperature field, material degradation degree, damage grade, and bearing capacity of the damaged bridge structure were evaluated separately, leading to general conclusions. From the perspective of maintenance and subsequent management after fire, more reasonable and targeted treatment ideas were suggested. Finally, according to the characteristics of such projects, relevant technical experience was summarized. Research has resulted in a complete set of technologies for structural inspection of bridges after fires，and the effective application of the technologies. The results show that the deterioration degree of concrete strength and reinforcement performance after fires is smaller than those of standard approaches. According to the situation, the bridge？？s carrying capacity can be reduced and