高寒地区特大桥混凝土盐冻性能配合比优化研究  

Research on optimization of mixture ratio of salt-freezing performance of concrete for large bridges in alpine region

作　　者：王维 WANG Wei(China Railway 19th Bureau Group Materials Co.,Ltd.,Shenyang 111000,China)

机构地区：[1]中铁十九局集团物资有限公司,辽宁沈阳111000

出　　处：《混凝土》2021年第5期119-122,共4页Concrete

摘　　要：基于正交试验,研究了引气量、用水量和水胶比等对C30混凝土(承台)、C40混凝土(桥面板)和C50混凝土(桥梁主塔)盐冻性能的影响规律并结合试验结果提出高寒地区桥梁混凝土配合比设计参考值。试验结果表明:用水量与引气量是影响桥梁混凝土盐冻性能的关键因素。其中,用水量从153 kg/m^(3)缩减至141 kg/m^(3),桥面板C40混凝土剥蚀量下降13%,经过300次冻融之后只有20%的其抗弯拉强度损失率;引气量处于4.5%~5.0%范围内时,经过300次冻融循环后,主塔C50混凝土的动弹模量相对值仍大于86%。Based on orthogonal experiments,it studies the influence of air entrainment,water consumption and water-binder ratio on the salt-freezing performance of C30 concrete(cap),C40 concrete(bridge deck)and C50 concrete(bridge main tower)and combines the test results.The design reference value of bridge concrete mix ratio in high-cold area is proposed.The test results show that water consumption and air entrainment are the key factors affecting the salt-freezing performance of bridge concrete.Among them,the water consumption was reduced from 153 kg/m^(3) to 141 kg/m^(3),and the amount of C40 concrete on the bridge deck was reduced by 13%.After 300 freeze-thaw cycles,only 20%of its flexural tensile strength loss rate.The air-entraining capacity was in the range of 4.5%~5.0%,after 300 freeze-thaw cycles,the relative value of the dynamic modulus of C50 concrete of the main tower is still greater than 86%.

关 键 词：桥梁 混凝土 配合比设计 冻融循环 

分 类 号：TU528.062[建筑科学—建筑技术科学]