摘要
以苏州某大型隧道盾构井侧墙大体积混凝土结构工程为依托,采用温控型钙镁复合膨胀剂配制的补偿收缩混凝土技术在实体结构中取得了良好的裂缝控制效果。结果表明,温控补偿收缩混凝土各龄期抗压强度值均达到了基准值的98%以上,水中14 d和水中14 d转空气中28 d的限制膨胀率数值分别高出0.029%和0.041%,具有良好的抗裂性能;混凝土配合比优化设计调整后,侧墙实体结构内部温峰值的出现时间延长5~8 h,温峰值降低4~5℃,早期降温速率也降低0.5~1.0℃/d,一个月龄期内温度修正后微应变的最大值和最小值分别增加了20~34με和51~81με。
Based on the mass concrete structure project of the side wall of a large tunnel shield well in Suzhou,the shrinkage-compensating concrete technology prepared by temperaturecontrolled calcium-magnesium composite expansive agent has achieved good crack control effect in the solid structure.The results showed that the compressive strength of temperature-controlled shrinkagecompensating concrete at each age reaches more than 98%of the reference value,and the limited expansion rate of 14d in water and 14 d in water to 28 d in air was 0.029%and 0.041%higher respectively,which had good crack resistance.After the optimization design and adjustment of the concrete mix ratio,the occurrence time of the internal temperature peak of the side wall solid structure was extended by 5~8h,the temperature peak was reduced by 4~5℃,and the early cooling rate was also reduced by 0.5~1.0℃/d.The maximum and minimum strains after temperature correction in one month were increased by 20~34μεand 51~81με,respectively.
作者
张恒睿
王金峰
王德民
ZHANG Heng-rui;WANG Jin-feng;WANG De-min(China Railway Engineering Design Consulting Group Co.,Ltd.,100055,Beijing,China;China Railway 14th Bureau Group Co.,Ltd.,250101,Ji'nan,China;Wuhan Sanyuan Special Building Materials Co.,Ltd.,430083,Wuhan,China)
出处
《建筑技术》
2025年第24期3015-3019,共5页
Architecture Technology
基金
湖北省住建厅2024年度科技计划项目(2024118)。
关键词
隧道盾构井
高大墙体
大体积混凝土
温控型钙镁复合膨胀剂
裂缝控制
tunnel shield shaft
high and large wall
mass concrete
temperature-controlled calciummagnesium composite expansion agent
crack control
