混凝土结构耐久性的分析.pdf

混凝土结构耐久性分析
Durability of . Structures Analysis



ABSTRACT


The carbonation of concrete is important factor affecting the durability of R. C. structures .
Firstly, by analyzing existing models of predicting concrete carbonation and its influencing
factors, a practical model of predicting the depth of carbonated concrete is proposed in this thesis,
which takes pressive strength of concrete as the main parameter and considers influence
of temperature and moisture of environment, construction factors, stress condition and density of
CO2 in the environment, and plenty of spot -data has been used to verify the model; By means of
regression analysis of the spot-data, the calculating model of uncarbonated remainder is
formulated; Considering the randomness of concrete carbonation, the paper put forward a
probability analysis method of concrete carbonation span-life. Secondly, applying the model of
predicting carbonated concrete, the model of predicting depth of steel corrosion and the method
of using durability estimation, which are established in the thesis, to the Jiang Xin Water Pump
Station of Wuhan Iron&Steel Corporation, the paper analyzed its residual carbonation span-life
on the basis of its durability investigation, which provides foundations to the decision of its
maintenance, strengthening and daily managements.


KEY WORDS:concrete durability,carbonation,uncarbonated remainder,carbonation
span-life


















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河北工业大学工程硕士学位论文
第一章绪论


§1-1 混凝土结构耐久性研究的意义

混凝土是当代用量最大的人造材料,也是最重要的建筑材料之一。由于混凝土具有许多优点而在实
际结构中得到广泛的应用,如高速公路、桥梁、高层和超高层建筑、海港工程、地下工程等,但随着时
间的推移,人们发现混凝土并不是永固的,它也会低于设计寿命而过早破坏,从而引起了人们对结构耐
久性的重视和研究,结构耐久性己成为工程界普遍关注的问题。
在结构工程中由于耐久性不足而导致结构破坏的事故时有发生,造成的经济损失是非常巨大的。
美国标准局(NBS) 1975 年的调查表明,美国全年各种由于腐蚀引起的损失为 700 亿美元,1985 年达到
1680 亿美元;在美国洲际公路网五十六万座桥中,处于严重失效的就有九万座,1969 年一年内用于修
复因钢筋锈蚀而损坏公路桥面板的费用高达 26 亿美元,1978 年增至 63 亿美元[1];美国材料咨询委员会
(NMAB) 1987 年的年度报告中指出