高抗拉组合桥面混凝土试验研究与应用  

Research&Application on TBM Extruded Concrete in Long and Large Tunnels at High Altitudes

作　　者：李科 刘建猛 孙武 LI Ke;LIU Jian-meng;SUN Wu(CCCC SHEC Wuhan Harbour New Materials Co,Ltd,Wuhan 430040,China;Wuhan Harbor Engineering Design&Research Institute Co Ltd,Wuhan 430040,China;Hubei Key Laboratory of Advanced Materials&Reinforcement Technology Research for Marine Environment Structures,Wuhan 430040,China)

机构地区：[1]中交二航武汉港湾新材料有限公司,武汉430040 [2]中交武汉港湾工程设计研究院有限公司,武汉430040 [3]海工结构新材料及维护加固技术湖北省重点实验室,武汉430040

出　　处：《建材世界》2024年第2期45-50,共6页The World of Building Materials

摘　　要：为解决高抗拉组合桥面混凝土存在的钢纤维掺量高、流动性差、经时损失大、泵送施工困难、早期强度低、易开裂等问题,试验通过原材料优选、配合比设计及优化,配制出流动性好、经时损失小、早期强度高、收缩率低的大掺量钢纤维混凝土,并将其应用于旧混凝土T梁与新钢纤维混凝土铺装层依靠剪力钉组合而成的桥面结构。结果表明:钢纤维混凝土不仅流动性好、2 h经时损失小,且1 d抗压强度达35 MPa以上,28 d抗弯拉强度达7 MPa以上,28 d干燥收缩仅有258×10^(-6),混凝土铺装层无裂缝、孔洞、漏筋、蜂窝、麻面等外观缺陷,应用效果良好。In order to solve the problems of high tensile composite bridge deck concrete,such as high steel fibre admixture,poor fluidity,high time loss,difficult pumping construction,low early strength,easy to crack,etc.,the test was carried out through the selection of raw materials,proportion design and optimization,and a large admixture of steel fibre concrete with good fluidity,low time loss,high early strength and low shrinkage was formulated,and was applied to the bridge structure consisting of old concrete T-beams and new steel fibre concrete decking layer.The bridge deck structure which relies on the combination of shear nails.The results show that the steel fibre concrete not only has good fluidity and small 2 h time loss,but also has 1 d compressive strength of more than 35 MPa,28 d flexural tensile strength of more than 7 MPa,28 d drying shrinkage of only 258×10^(-6),and no appearance defects of concrete deck such as cracks,holes,leakage of tendons,honeycomb,pockmarked surface and so on,which has a good application effect.

关 键 词：高抗拉 组合桥面 钢纤维混凝土 泵送施工 

分 类 号：U444[建筑科学—桥梁与隧道工程]