预应力混凝土重载轨枕表面气孔防治措施  

Preventive Measures of Surface Blowhole of Prestressed Concrete Heavy Sleepers

作　　者：王创江 兰英静[2] 孙成晓 

机构地区：[1]陕西省土地工程建设集团,西安710000 [2]青岛农业大学海都学院,莱阳265200 [3]北京铁科首钢轨道技术股份有限公司,102206

出　　处：《混凝土与水泥制品》2018年第10期41-43,共3页China Concrete and Cement Products

摘　　要：混凝土表面气孔麻面是影响预应力混凝土轨枕表观质量的主要因素之一,严重时会影响轨枕的耐久性能。重载预应力混凝土轨枕尺寸较大,在生产过程中容易在轨枕下部出现气孔,通过对混凝土原材料、配合比、振捣工艺及脱模剂种类等因素进行对比试验,系统分析了轨枕表面产生气孔麻面的原因。研究结果表明,适当减小干硬性混凝土增实因数可减少表面气泡数量,增实因数在1.25～1.30时,混凝土表观质量较好;增大混凝土砂率可减小气泡孔径;提高含气量可明显改善混凝土表面状况,含气量在2.5%时,混凝土表面气泡最少。The stomatal surface of concrete is one of the main factors affecting the apparent quality of prestressed concrete sleepers, which can affect the durability of sleepers in serious cases. Heavy load prestressed concrete sleepers have a large size and are prone to air holes in the lower part of the sleepers during the production process. By comparing the concrete raw material, the mix ratio, the vibration process and the type of demoulding agent, the reason for the production of Burr surface on the surface of the rail pillow was analyzed. The experimental results show that increasing the sand rate of concrete can reduce the air bubble aperture. Proper reduction of the dry concrete increase factor can reduce the number of surface bubbles, and when the increase factor is 1.25-1.30, the surface quality of the concrete is better. The surface condition of concrete can be obviously improved by increasing the gas content. When the gas content is 2.5 %, the concrete sur-face bubbles are the least.

关 键 词：干硬性混凝土 气泡 轨枕 

分 类 号：TU528[建筑科学—建筑技术科学]