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（1 西安建筑科技大學土木工程學院， 西安 710055； 2 中國建筑科學研究院有限公司， 北京 100013）

［摘要］混凝土碳化系數(shù)是一般大氣環(huán)境下混凝土結構耐久性的重要指標，為研究實驗室加速碳化和工程結構自然碳化的相關性，在北京地區(qū)暴露26年的混凝土長觀試件的多次實測碳化深度基礎上，從長觀試件中鉆取未碳化的混凝土制作成圓柱體試件，在實驗室進行加速碳化試驗，分析實驗室加速碳化和室外自然碳化的規(guī)律，并研究兩者實測碳化系數(shù)的相關性。結果表明，混凝土抗壓強度值從29-8MPa增長到57-2MPa，增幅接近一倍，加速碳化28d的碳化深度和50年自然碳化深度基本接近，從混凝土抗碳化能力隨強度增長而提高的角度考慮，采用齡期28d混凝土試塊的加速碳化試驗結果作為混凝土耐久性設計或者評估的依據(jù)是偏于保守的做法。

［關鍵詞］混凝土碳化； 長觀試件； 自然環(huán)境； 加速試驗； 相關性

中圖分類號：TU528文獻標識碼：A文章編號：1002-848X(2019)09-0111-04

Experimental study on correlation between natural carbonation and accelerated carbonation of long-term observation concrete specimens

Sun Bin1,2, Mao Shiyang2, Wang Jingxian2, Di Xiaotan2, Ren Ronghong2

（1 School of Civil Engineering, Xi′an University of Architecture and Technology, Xi′an 710055, China;2 China Academy of Building Research, Beijing 100013, China)

Abstract:The carbonation coefficient of concrete is an important indicator of the durability of concrete structures in general atmospheric environment. In order to study the correlation between the accelerated carbonization in laboratory and the natural carbonization of engineering structures, the uncarbonized concrete was drilled from the long-term observation specimen to make a cylindrical experimental piece, based on the multiple measured carbonization depths of concrete long-term observation specimens exposed in Beijing for 26 years. Accelerated carbonization experiment was carried out in the laboratory to analyze the laws of accelerated carbonization in the laboratory  and outdoor natural carbonization, and to study the correlation between the measured carbonization coefficients under the two conditions. The results show that the compressive strength of concrete increases from 29-8MPa to 57-2MPa, and the increase is nearly doubled. The carbonization depth of accelerated carbonization for 28d is almost the same as the natural carbonization depth of 50 years. From the perspective of  the carbonation resistance of concrete increasing with the increase of strength, it is a conservative measure to adopt accelerated carbonization experimental results of the 28d concrete specimen as the basis for the design or evaluation of concrete durability.

Keywords:concrete carbonation; long-term observation specimen; natural environment; accelerated experiment; correlation