摘要
运用系统识别原理 ,结合混凝土材料的微观孔结构模型建立了材料微孔结构识别理论 .在该理论中 ,混凝土材料在复杂环境条件下的早期变形可由孔结构模型来反映 ;同时通过有限单元法 ,可以实现温度、湿度和变形多场耦合的数值模拟 .系统识别的数值算法采用寻找复杂目标函数最优值的复合形法 ,为避免搜索到局部最优值 ,还采用了多重随机搜索的方式 .最后用系统识别的结果来预测自密实混凝土的早期变形 ,预测结果证明了识别结果的合理性和所采用模型的适应性 .
System identification is one of the methods to model complex systems.Based on the theory of system identification and the micro pore structure in concrete,one new theory is found to inversely analyzes the micro pore structure,in which the early strain of concrete can be simulated by the micro pore structure,and the thermal,humid and strain fields can be calculated at the same time.The complex algorithm is used as the numerical method during the progress.Thrice stochastic search is used in case of the local optimization.Finally,the early strain of self compacting concrete is predicted through the results got from the new theory.And the predicted strain shows that the results from system identification are reasonable and the numerical model cited is applicable.
出处
《同济大学学报(自然科学版)》
EI
CAS
CSCD
北大核心
2003年第6期709-713,共5页
Journal of Tongji University:Natural Science
关键词
自密实混凝土
微孔结构
系统识别
早期变形
有限元
self compacting concrete
micro pore structure
system identification
early strain
finite element