寒冷干旱地区桥墩保温养护方法研究  

Study on Thermal Insulation and Maintenance Method of Bridge Pier in Cold and Arid Area

作　　者：欧阳天武 OUYANG Tianwu(China Railway 20^(th)Bureau Group No.4 Engineering Co.Ltd.,Qingdao Shandong 266061,China)

机构地区：[1]中铁二十局集团第四工程有限公司,山东青岛266061

出　　处：《铁道建筑技术》2023年第3期105-109,共5页Railway Construction Technology

基　　金：中铁二十局集团有限公司科技研发计划项目(YF2104QL03C)。

摘　　要：依托鹤岗特大桥项目,根据桥墩水化热传导机理确定了橡塑板+防水棉被的保温保湿养护方式和保温材料厚度。通过有限元软件计算出了不同工况下的混凝土桥墩中心点以及表面点的水化热温度和应力;进行了现场试验,对数值分析结果进行了验证。结果表明:无保温养护措施时,混凝土桥墩中心点温度远大于表面点温度,桥墩表面应力超过抗拉强度,有可能造成混凝土的开裂。通过橡塑板+防水棉被的保温保湿养护方式,基本将混凝土桥墩内外温差控制在20℃以内,有效减小混凝土桥墩表面的实际应力峰值,为防止混凝土开裂提供可靠保障。In this paper,based on Hegang Bridge project,according to the hydration and heat conduction mechanism of bridge pier,the heat preservation and moisture-keeping euring mode of rubber board and waterproof quilt and the thickness of heat preservation material are determined.The hydration heat temperature and stress of the center point and surface point of concrete pier under different working conditions are calculated by finite element software.Field tests were carried out to verify the results of numerical analysis.The results show that,without heat preservation and maintenance measures,the temperature at the center of the concrete pier is much higher than that at the surface,and the surface stress of the pier exceeds the tensile strength,which may lead to concrete cracking.The temperature difference between the inside and outside of the concrete pier is basically controlled within 20℃by the heat preservation and moisture conservation method of rubber board and waterproof quilt,which effectively reduces the actual stress peak value on the surface of the concrete pier and provides a reliable guarantee for preventing concrete cracking.

关 键 词：桥墩养护 橡塑板 里表温差 干旱 

分 类 号：U443.22[建筑科学—桥梁与隧道工程] U445.43[交通运输工程—道路与铁道工程]