大跨度PC连续刚构桥徐变预测模型

Models for predicting creep of continuous rigid frame bridge using prestressed concrete

为了能准确预测混凝土收缩徐变,提出了一系列徐变预测模型,但传统的徐变理论研究主要是针对普通混凝土进行的,所提出的徐变模型并不能完全适用于高强混凝土。对各徐变预测模型进行分析比较,最终参考了日本混凝土示方书建议模型,并在高强混凝土徐变试验的基础上,提出了一个适用于高强混凝土的徐变预测模型。基于Abaqus平台,使用Python语言进行二次开发,定义了修正模型的徐变规律,并采用修正后的模型计算牛角坪大桥的徐变应变。结果表明,修正模型的精度,能很好的满足工程需求。

Nowadays all the existed prediction models around the world are only suitable for ordinary concrete with a strength lower than C40 or lightweight aggregate concrete with a strength under C30, however, there exists no prediction model for high strength concrete structures. Through the analysis and comparison of each creep prediction model, this paper concludes with reference to the proposed model of Japanese Concrete Codes. On the basis of creep test of high strength concrete, a creep prediction model for high strength concrete is proposed. Based on Abaqus Scriping Interface, new user＇s material properties that fitted Modified Model were created by Python. By comparing results of calculation and test data, a rule of creep＇s progress was obtained.