权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Quantitative Evaluation on Decline Process of Performances of Concrete Structures

混凝土结构性能下降过程的定量评价

基本信息

批准号：
09650511
负责人：
TAKEWAKA Koji
金额：
$ 2.18万
依托单位：
Kagoshima University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1998
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09650511/
关键词：
Concrete Structure Long-term Performance Declination of Performance Prediction of Deterioration Chloride Attacked Environment Hot Springs Environment Defects Due to Inferior Construction Computer Simulation for Deterioration Process 複合劣化

项目摘要

In this study, the influence of concrete deterioration and/or reinforcement corrosion on performances of concrete structure, such as bearing capacity, seismic capacity, fatigue property esthetics et al., was mainly examined, and the decline processes of these performances were quantified. The main results of this study are as follows ;1. Development of computer simulation method for chloride induced reinforcement corrosion :A computer simulation method for the chloride induced reinforcement corrosion in concrete has been developed in consideration of the effects of micro and macro pores in concrete, on the diffusion processes of chloride and oxygen. This method is useful for evaluating the influence of concrete quality, water content and crack existing in concrete on the corrosion process of reinforcing steel quantitatively.2. Influence of the reinforcement corrosion on the fatigue property of concrete structure :An equation predicting the decline of fatigue property of concrete struct … More ure due to reinforcement corrosion was proposed. In this equation, the pitting corrosion was introduced as a main factor causing the micro crack propagation into cross section of steel bar. Accuracy of the equation was confirmed by the fatigue test of reinforced concrete beams deteriorated due to the reinforcement corrosion.3. Influence of defects built up by the inferior construction on the mechanical properties of concrete structures :When some defects, such as honeycomb, large void and the irregular materials, exist in concrete due to the inferior construction, the mechanical properties of concrete structure would be affected by them. Some experimental study was done for clarifying the influences of the defects on the bearing capacity, toughness and fatigue property of reinforced concrete beams. From the results, it was confirmed that the fatigue property of the beams clearly declined on account of existing the defects in concrete even if no declination sign was appeared on the static bearing capacity.4. Deterioration prediction of concrete under hot spring water :Quantitative equations to predict the deterioration of concrete in the hot spring water were provided on the basis of analyzing the data obtained from the exposure tests under the several hot spring areas in Japan. Adequacy of the equations was checked by the results of the exposure test carried out newly in this study. Less

本文研究了混凝土劣化和钢筋锈蚀对混凝土结构承载力、抗震能力、疲劳性能、美观等性能的影响，并对这些性能的下降过程进行了量化。本研究的主要结果如下：1。氯离子腐蚀钢筋的计算机模拟方法的发展：考虑混凝土中微孔和大孔对氯离子和氧扩散过程的影响，建立了混凝土中氯离子腐蚀钢筋的计算机模拟方法。该方法可用于定量评价混凝土质量、含水量及混凝土中存在的裂缝对钢筋锈蚀过程的影响.钢筋腐蚀对混凝土结构疲劳性能的影响：混凝土结构疲劳性能下降的预测方程 ...更多信息提出了钢筋锈蚀的原因。在该方程中，点蚀是引起钢筋横截面微裂纹扩展的主要因素。通过钢筋锈蚀劣化钢筋混凝土梁的疲劳试验，验证了该方程的准确性.不良施工产生的缺陷对混凝土结构力学性能的影响：当混凝土中存在蜂窝状、大空隙、不规则材料等不良施工缺陷时，会对混凝土结构的力学性能产生影响。为阐明缺陷对钢筋混凝土梁承载力、韧性和疲劳性能的影响，进行了试验研究。研究结果表明，尽管梁的静载承载力没有下降的迹象，但由于混凝土中存在缺陷，梁的疲劳性能明显下降.混凝土在温泉水作用下的劣化预测：通过对日本几个温泉地区的暴露试验数据的分析，提出了预测混凝土在温泉水作用下劣化的定量方程。用本研究中新进行的暴露试验的结果检验了方程的正确性。少