摘要
根据桥梁工程结构特点，提出了桥梁清水混凝土的配合比优化设计方法，制备出粘聚性与包裹性好、流动度佳，且具有优良力学性能的C30～C50高性能清水混凝土。通过对混凝土拌合物含气量、硬化试件不同部位显微硬度与微观结构的测试，分析了增粘剂对其匀质性的影响规律。试验表明：对于C30桥梁清水混凝土，掺5×10－5的纤维素醚或掺6％的硅灰时，混凝土的含气量不超过2％，浆体旋转粘度值在1900～2000 M Pa · s之间，试件不同部位显微硬度值接近，匀质性好，结构密实。
Abstract
According to the structural characteristics of bridge engineering , the mix optimization design method of bridge fair‐faced concrete was presented , and C30 ~ C50 concrete with high cohesion and package ,outstanding fluidity and excellent mechanical properties were prepared .Through the test of air content of fresh concrete , micro hardness and micro structure in different parts of hardened concrete specimens ,effects of viscosity‐modifying admixtures on homogeneity of concrete were discussed . The results showed that the composition of bridge fair‐faced concrete were relatively homogeneous ,and the microstructure were relatively dense .When C30 concrete mixed with 5 × 10-5 cellulose ether or 6% silica fume (mass fraction of cementitious material ) ,air content of fresh concrete were less than 2% ,and slurry viscosity values were between 1 900 and 2 000 MPa · s .Also ,the micro hardness values in different parts of hardened concrete specimens were closed . The results were applied in practical bridge engineering , w hich generally meets the apparent quality requirements of bridge fair faced concrete .
NETL
NSTL
维普
万方数据