Abstract: The properties of High-Strength Concrete（HSC） are studied after high temperature.The main factors influencing the concrete structure fired are analyzed，and the strength damage coefficient，durability damage coefficient.In addition，the spalling degree and crack width of HSC are chosen as the criterion indices for concrete structure classification.An HSC by fired evaluation method is established.Its project direction using population migration algorithm is optimized，and the model is applied to classify in an example.The evaluation results are accurate.This method is simple，and some errors are eliminated because of the subjective factors for traditional methods.Projection pursuit is a new evaluation method judging and classifying the HSC by fire.It has provided scientific basis for diagnosis，evaluation，repairing and strengthening of HSC structure damage by fire.

Key words: high strength concrete, damage by fire, projection pursuit, population migration algorithm, comprehensive evaluation

摘要： 在研究高强混凝土高温后性能的基础上，通过对影响火灾后高强混凝土结构性能的主要因素进行分析，选择抗压强度损失系数、耐久性损失系数、爆裂损失系数和裂纹损失系数作为评价指标，以投影寻踪回归理论为基础，提出综合评定高温后损伤混凝土性能的方法，建立了投影寻踪综合评价模型，编制了基于MATLAB的相应程序，采用人口迁移算法寻求最优投影方向，根据投影特征指标值对高强混凝土高温后性能进行综合评价。研究表明，该方法避免了评判专家人为确定权重，评价结果客观准确、方法简单，为混凝土结构火灾损伤的诊断评估与修复加固提供科学依据。

关键词: 高强混凝土, 受火损伤, 投影寻踪回归, 人口迁移算法, 综合评价