日本混凝土裂缝原因及其对策研究动向

CAUSES OF CONCRETE CRACKS IN JAPAN ETC.AND THEIR PROSPECTS OF TREATMENT MEASURES

使混凝土产生裂缝的原因一是材料因素 ,包括骨料、水泥、掺合材料 ;二是施工因素 ,包括混凝土的配合、拌制、运输、浇筑和养护 ;三是混凝土恶化因素 ,即钢筋腐蚀和碱集料反应。日本、美国等国家已有对裂缝宽度的容许值 。

The causes of producing concrete cracks are numerous namely:(1)building materials' factors such as their aggregates,cement,and admixtures,(2) construction factors such as their concrete mixing ratio,mixing process,transportation,pouring and curing methods,and (3) deterioration factors of concrete,corrosion of steel bars and reactions of alkali-aggregates.Currently,there are technical norms about concrete cracks' width,length and thickness etc.being published in Japan and USA etc.Besides,some treatment measures for concrete cracks' control have been put forward. Key words concrete, crack, reaction of alkali-aggregate Match Using Wavelet Transform$$$$ JIANG Xiao yu (Institute of Remote Sensing Application, Chinese Academy of Sciences, Beijing 100101) HUANG Ying qing (Department of Electronic Engineering, PLA Armoring Engineering Insititute, Beijing 100072)Abstract In the conventional hierarchical template matching, there exists a typical problem of sophisticated calculation and correction. In this paper a new multiresolution template matching algorithm based on wavelet transform has been studied. According to the numerical and experimental comparison, it is showed that the new algorithm has eliminated the background intensity effect to the template matching, and it has the advantage of easy to calculate and parallel process.