论文部分内容阅读
混凝土在火灾等高温条件下的爆裂,会给整个建筑结构的安全带来严重危害。目前,混凝土结构的高温爆裂风险分析与评价已经成为混凝土结构抗火性能研究的热点,而模糊数学理论是分析此类问题的最有效方法之一。混凝土爆裂现象比较复杂,必须综合考虑材料和外部环境2个方面的因素。选择混凝土强度、水灰比、纤维量、养护湿度、荷载水平和升温速率组成影响因素集,并按各因素的重要性赋以不同的权重,应用模糊数学理论建立混凝土结构高温爆裂风险模糊综合评价模型。先随机选取10个混凝土试样组成待评价爆裂风险的混凝土样本集;然后形成该样本集的指标特征值矩阵,并转换为相应的相对隶属度矩阵;结合权重,可得10个混凝土试样相对5个爆裂风险级别的相对隶属度矩阵;最后,计算出待评价的10个混凝土试样的爆裂级别特征值。爆裂风险预测与试验的结果一致,表明所建立的模型能有效地评价混凝土高温爆裂风险。
Concrete in the fire and other high temperature conditions of the burst, will bring serious harm to the safety of the entire building structure. At present, the risk analysis and evaluation of high temperature burst of concrete structures has become a hot spot in the study of fire resistance of concrete structures. Fuzzy theory is one of the most effective ways to analyze such problems. Concrete burst phenomenon is more complicated, we must consider the material and the external environment in two aspects of the factors. The influencing factors of concrete strength, water-cement ratio, fiber content, curing humidity, load level and heating rate were selected. According to the importance of each factor, different weights were chosen. Fuzzy fuzzy theory was applied to establish fuzzy comprehensive evaluation of burst risk of concrete structures. model. Firstly, ten concrete samples are randomly selected to form the concrete sample set with the risk of burst to be evaluated. Then the matrix of the eigenvalues of the samples is formed and transformed into the corresponding relative membership matrix. With the weight, 10 concrete samples are obtained, Five burst risk level relative membership matrix. Finally, the eigenvalue of the burst level of ten concrete samples to be evaluated is calculated. The prediction of burst risk is consistent with the experimental results, indicating that the established model can effectively evaluate the burst risk of concrete at high temperature.