无粘结预应力高性能粉煤灰混凝土桥梁收缩与徐变变形试验研究

结合洛湛线的建设,以8根不同掺量的高性能粉煤灰混凝土无粘结预应力桥梁的收缩、徐变试验为基础,研究了不同掺量高性能粉煤灰混凝土在荷载长期作用下收缩、徐变性能及其上拱随时间的变化规律,探讨了温度、湿度等环境因素对不同掺量高性能粉煤灰混凝土收缩、徐变的影响。300多天的实验观测结果表明:高性能粉煤灰掺量20%～40%混凝土梁不但具有良好的工作性能和力学性能,而且长期性能良好,与同强度的未掺高性能粉煤灰的梁相比,其后期强度和抗压弹性模量增大,收缩徐变减小,具有良好的社会和经济效益。

EXPERIMENTAL STUDY ON THE DEFORMATIONS FOR SHRINKAGE AND CREEP OF BEAMS IN NON- GLUED PRESTRESSED HIGH PERFORMANCE FLY ASH CONCRETE BRIDGES

Using the construction of the railway between Luoyan and Zhanjiang as background, based upon the experimental results of shrinkage and creep of eight non-glued concrete beams with different mixtures of high-performance fly ash, the shrinkage, creep and camber of beams with different mixtures of high-performance fly ash concrete under long-term loadings are investigated. The effects of the environmental factors such as temperature, humidity are also explored, the experimental results over 300 days indicate that the non-glued concrete beams with 20%-40% high performance fly ash not only have better workability and mechanical properties, but also exhibit better long-term performance. Compared with concrete beams of same strength but without fly ash, they have higher late-stage strength and compressive elastic modulus, lower shrinkage and less creep with esirable social and economic profitability.