(1 湘潭大学土木工程与力学学院，湘潭 411105；2 长沙理工大学土木工程学院，长沙 410114)

［摘要］为了研究环境温度和混凝土强度对混凝土碳化的影响，在标准快速碳化试验的基础上，设计了不同强度的混凝土试件在不同温度下的碳化试验，明确了温度和强度对混凝土碳化性能的影响。基于实测数据提出了以强度和温度为主要参数的碳化深度预测模型。在该模型的基础上，结合各参数的统计分布特征，分析了混凝土结构碳化失效概率特征。研究表明：环境温度和混凝土强度对混凝土碳化影响显著，温度越高或混凝土强度越低，碳化速度越快，碳化深度也越深。混凝土强度在碳化初期对碳化速率的影响较大，随碳化的加深影响逐渐减小；当温度从20℃提高至30℃时，实测强度为28MPa和34MPa混凝土试件平均碳化深度分别增长约56%和62%；混凝土结构碳化失效概率和可靠指标退化对混凝土保护层厚度最为敏感，其次是混凝土强度和环境温度。

［关键词］环境温度；混凝土强度；碳化深度预测模型；碳化概率分析；可靠性分析

中图分类号：TU375文献标识码：A文章编号：1002-848X(2020)24-0110-06

Experimental study on concrete carbonation performance under the influence of different temperature and strength

ZHANG Xuhui1,2, LIU Bowen1, YANG Ling1, LUO Yuming2, YANG Caiqian1

(1 College of Civil Engineering and Mechanics, Xiangtan University, Xiangtan 411105, China; 2 School of Civil Engineering, Changsha University of Science and Technology, Changsha 410114, China)

Abstract:In order to study the influence of environmental temperature and concrete strength on concrete carbonation, based on the standard rapid carbonization test, the carbonization tests of concrete specimens with different strengths at different temperatures were designed to clarify the influence of temperature and strength on the carbonization performance of concrete. The carbonization depth prediction model with strength and temperature as the main parameters was proposed according to the measured data. On the basis of the model, the failure probability characteristics of concrete structures were analyzed combined with the statistical distribution characteristics of various parameters. Research shows that both environmental temperature and concrete strength have significant influence on concrete carbonization. The higher the temperature or the lower the concrete strength is, the faster the carbonization rate is and the deeper the carbonization depth is. The strength of concrete has a significant influence on the carbonization rate at the beginning, and gradually decreases with the deepening of carbonization. The average carbonation depth of concrete specimens with measured strength of 28MPa and 34MPa increases about 56% and 62% respectively when the temperature increases from 20℃ to 30℃. The carbonation failure probability and reliability index degradation of concrete structure are most sensitive to the thickness of concrete protective layer, followed by concrete strength and environmental temperature.

Keywords:environmental temperature; concrete strength; carbonization depth prediction model; carbonization probability analysis; reliability analysis

*国家自然科学基金项目(51708477)，中国博士后科学基金资助项目(2018T110837, 2017M620350)。

作者简介：张旭辉，博士，副教授，Email: xuhui.zhang@xtu.edu.cn；通信作者：杨才千，博士，教授，Email: ycqjxx@hotmail.com。