- 摘 要
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（中國十七冶集團有限公司 技術(shù)中心，中國 馬鞍山，243000）
[摘要] 在役RC結(jié)構(gòu)中鋼筋銹蝕是一個分段加速的過程，其對結(jié)構(gòu)構(gòu)件產(chǎn)生的負效應(yīng)較混凝土碳化開裂更為明顯，據(jù)此給出了一般大氣環(huán)境下鋼筋混凝土結(jié)構(gòu)隨內(nèi)嵌鋼筋銹蝕而出現(xiàn)性能劣化的主要服役階段劃分規(guī)則，并就內(nèi)嵌縱筋未銹階段和保護層混凝土開裂階段RC構(gòu)件服役時間的計算方法進行了探討。通過引入混凝土碳化殘量以彌補主流觀點關(guān)于鋼筋表面鈍化膜失效時間研究的不足，并基于實測數(shù)據(jù)擬合得到一般大氣環(huán)境下保護層混凝土碳化殘量計算模型，提出了內(nèi)嵌鋼筋開始銹蝕時間的計算公式；基于彈性力學(xué)相關(guān)理論，建立了鋼筋銹脹所引起的鋼筋混凝土構(gòu)件保護層混凝土發(fā)生開裂時鋼筋銹蝕率計算模型，并揭示了諸如混凝土抗拉強度標準值、混凝土保護層厚度、鐵銹泊松比、鋼筋直徑及鐵銹銹脹率等主要影響因素對鋼筋銹蝕率的影響規(guī)律，最終給出了保護層混凝土脹裂時RC構(gòu)件服役時間的建議計算公式。研究成果可為在役RC結(jié)構(gòu)力學(xué)性能分析提供理論參考。
[關(guān)鍵詞] 一般大氣環(huán)境；RC構(gòu)件；服役時間；碳化殘量；銹脹開裂
中圖分類號：TU313.1; TU375 文獻標識碼：A 文章編號：
Study on calculating method for typical service time of RC component under common atmosphere environment
Yin Wanyun, Hu Yi
(Technology Center, China MCC17 group Co., Ltd., Maanshan 243000,
Abstract: Reinforcement corrosion of existing RC frame structure component is accelerated with stages, and it’s negative effects to structure component are more obviously than concrete carbonization cracking does. The classification principle for main service stages of RC structure performance degradation which caused by reinforcement corrosion in common atmosphere environment is provided, and the methods for calculating service time of RC component before reinforcement corrosion and concrete carbonization cracking are discussed in this paper. By introducing concrete carbonated residue content to make up the lack of studies on rebar surface passive film failure time, calculating formulas for defining the start time of reinforcement corrosion is proposed according to covered concrete carbonated residue content suggested calculating model which is obtained from regressive analysis of measured data. Based on the correlation theory of elasticity, model for calculating reinforcement corrosion rate when the covered concrete is beginning to crack which caused by reinforcement corrosion expansion is established, and the influence law of concrete tensile strength, concrete cover depth, rust poisson ratio, reinforcement diameter and rust corrosion expansion rate on reinforcement corrosion rate is revealed, then the suggested formulas for calculating service time of RC component before covered concrete cracking is finally obtained. The achievements will provide references to mechanics property analysis of existing RC frame structure.
Keywords: common atmosphere environment; RC component; service time; carbonated residue content; corrosion crack
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