基于RF的模拟海洋环境下FRP筋混凝土界面黏结强度的耐久性研究  

Durability analysis of interfacial bond strength between FRP bars and concrete insimulated marine environment

作　　者：谭欣怡 黄丽华 TAN Xinyi;HUANG Lihua(Institute of Engineering Mechanics,Dalian University of Technology,Dalian 116024,China)

机构地区：[1]大连理工大学建设工程学部,辽宁大连116024

出　　处：《混凝土》2025年第3期79-84,90,共7页Concrete

基　　金：国家自然科学基金(51678115)。

摘　　要：随着FRP筋混凝土材料在港口码头、桥梁隧道等结构中越来越广泛地应用,其耐久性设计备受关注.基于不同温度的海水(碱性)环境下的加速老化试验结果,利用随机森林(RF)算法,开展模拟海洋环境下FRP筋混凝土界面黏结强度剩余率预测模型研究.通过计算分析315组耐久性拉拔试验的界面强度剩余率,基于数据分布选取142组数据点建立数据库,按4∶1比例随机选取数据构建训练集和验证集,采用训练集建立预测黏结强度剩余率的RF模型,利用验证集数据检验RF模型的预测精度,保证RF模型的预测平均误差在5%以内.采用RF模型分析界面黏结强度剩余率影响参数的敏感性,基于SHAP方法计算输入参数对黏结强度剩余率的影响系数,得到在模拟海洋环境下影响FRP筋混凝土界面耐久性的主要因素,即劣化时长、FRP筋直径、锚固长度、FRP筋种类、混凝土强度、pH值和温度的影响依次减弱,研究成果对在海洋环境下FRP筋混凝土结构的耐久性设计提供有益参考。With the increasingly widespread application of FRP reinforced concrete in structures such as ports,wharves,bridges and tunnels,their durability design has attracted much attention.Based on the experimental data of accelerated aging in seawater(alkaline)environment at different temperatures in the literature,random forest(RF)algorithm was used to carry out the prediction model of the residual rate of interfacial bond strength between FRP bars and concrete under the simulated marine environment.By calculating and analyzing the interfacial bond strength residual rate of 315 groups of pull-out specimens,142 groups of data points were selected based on data distribution to establish a database.The training set and validation set were randomly selected in a 4∶1 ratio to establish an RF model for predicting the interfacial bond strength residual rate.The validation set data was used to verify the prediction accuracy of the RF model,ensuring that the average prediction error of the RF model was within 5%.Using the RF model to analyze the sensitivity of the parameters affecting the interfacial bond strength residual rate,and based on the SHAP method to calculate the coefficient of influence of input parameters on the interfacial bond strength residual rate,the main factors affecting the durability of interfacial bond strength in marine environments were obtained,namely the weakening of the effects of degradation time,diameter of FRP bars,anchorage length,type of FRP bars,concrete strength,pH,and temperature.The results provide useful references for the durability design of FRP reinforced concrete structures in marine environments.

关 键 词：FRP筋混凝土 界面强度剩余率 耐久性 影响参数 RF方法 

分 类 号：TU528.571[建筑科学—建筑技术科学]