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(1 湘潭大學(xué)土木工程與力學(xué)學(xué)院，湘潭 411105；2 長(zhǎng)沙理工大學(xué)土木工程學(xué)院，長(zhǎng)沙 410114)

［摘要］為了研究環(huán)境溫度和混凝土強(qiáng)度對(duì)混凝土碳化的影響，在標(biāo)準(zhǔn)快速碳化試驗(yàn)的基礎(chǔ)上，設(shè)計(jì)了不同強(qiáng)度的混凝土試件在不同溫度下的碳化試驗(yàn)，明確了溫度和強(qiáng)度對(duì)混凝土碳化性能的影響。基于實(shí)測(cè)數(shù)據(jù)提出了以強(qiáng)度和溫度為主要參數(shù)的碳化深度預(yù)測(cè)模型。在該模型的基礎(chǔ)上，結(jié)合各參數(shù)的統(tǒng)計(jì)分布特征，分析了混凝土結(jié)構(gòu)碳化失效概率特征。研究表明：環(huán)境溫度和混凝土強(qiáng)度對(duì)混凝土碳化影響顯著，溫度越高或混凝土強(qiáng)度越低，碳化速度越快，碳化深度也越深?；炷翉?qiáng)度在碳化初期對(duì)碳化速率的影響較大，隨碳化的加深影響逐漸減小；當(dāng)溫度從20℃提高至30℃時(shí)，實(shí)測(cè)強(qiáng)度為28MPa和34MPa混凝土試件平均碳化深度分別增長(zhǎng)約56%和62%；混凝土結(jié)構(gòu)碳化失效概率和可靠指標(biāo)退化對(duì)混凝土保護(hù)層厚度最為敏感，其次是混凝土強(qiáng)度和環(huán)境溫度。

［關(guān)鍵詞］環(huán)境溫度；混凝土強(qiáng)度；碳化深度預(yù)測(cè)模型；碳化概率分析；可靠性分析

中圖分類號(hào)：TU375文獻(xiàn)標(biāo)識(shí)碼：A文章編號(hào)：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

*國(guó)家自然科學(xué)基金項(xiàng)目(51708477)，中國(guó)博士后科學(xué)基金資助項(xiàng)目(2018T110837, 2017M620350)。

作者簡(jiǎn)介：張旭輝，博士，副教授，Email: xuhui.zhang@xtu.edu.cn；通信作者：楊才千，博士，教授，Email: ycqjxx@hotmail.com。