基于模糊层次分析法的混凝土结构耐久性等级评估模型及应用

为客观地评价影响混凝土结构耐久性的多要素间的耦合作用和影响程度,相对准确地评估水工建筑物的服役状态和耐久性等级,以甘肃省景泰川电力提灌灌区二期工程总干渠#5渡槽混凝土结构耐久性评估为例,将影响结构耐久性的要素分解为环境、材料、人为3个子系统,通过构建影响各子系统的多级指标体系,运用模糊层次分析法(FAHP)建立多层次多指标的混凝土建筑物耐久性综合评估模型;定义了水工建筑物服役的Ⅰ～Ⅴ级共5个耐久性状态,基于模糊数学理论将指标定量化,通过可拓区间判断矩阵计算各层指标权重,结合模糊综合评价法进行逐级评估,从而实现了以综合评估值来定量描述混凝土建筑物的耐久性水平。评估结果表明,其综合评估值为65.76,根据等级划分确定耐久性等级为Ⅱ级,准确反映了渡槽的实际服役状态。可见该模型可较好地表征水工混凝土结构耐久性等级,具有一定的实际应用价值。

Durability Grade Evaluation Model of Concrete Structure Based on Fuzzy Analytic Hierarchy Process and Its Application

In order to objectively evaluate the coupling and influence degree of multiple factors affecting the durability of concrete structures, and to relatively accurately evaluate the service state and durability grade of hydraulic structures, taking the #5 aqueduct of the main trunk of the second phase of Jingtaichuan Electric Power Irrigation District in Gansu Province as the evaluation object, the factors affecting the structural durability were decomposed into three subsystems: environment, material and man-made. By constructing a multi-level index system affecting each subsystem, the fuzzy analytic hierarchy process (FAHP) was applied to establish a multi-level and multi-index concrete building durability evaluation model. The paper defined five durability states of the I-V class for the service of hydraulic structures, and quantified the indicators based on fuzzy mathematical theory. The extension interval judgment matrix was used to calculate the index weights of each layer, and the fuzzy comprehensive evaluation method was combined to carry out level-by-level evaluation, thereby the comprehensive evaluation value to quantitatively describe the durability level of concrete buildings was realized. The evaluation results show that the comprehensive evaluation value is 65.76, and the durability level is determined to be level II according to the classification, which accurately reflects the actual service state of the aqueduct. It can be seen that the model can well characterize the durability grade of hydraulic concrete structures, and has certain practical application value.