超长超宽现浇隧道侧墙混凝土温度及应力参数化分析与应用  

Application and Parameterized Analysis of Temperature and Stress of Side Wall Concrete of Super long and Super wide Cast-in-situ Tunnel

作　　者：蔺威威 蔡伟 谷坤鹏 LIN Wei-wei;CAI Wei;GU Kun-peng(CCCC Shanghai Harbor Engineering Design and Research Institute Co.Ltd.,Shanghai 200032,China;CCCC Third Harbor Engineering Co.Ltd.,Shanghai 200030,China)

机构地区：[1]中交上海港湾工程设计研究院有限公司,上海市200032 [2]中交第三航务工程局有限公司,上海市200030

出　　处：《公路》2024年第12期450-457,共8页Highway

基　　金：国家重点研发项目,项目编号2022YFB3706504;江苏省交通工程建设局科技研发资助项目,项目编号CX-KY-08。

摘　　要：为解决基于多场耦合机制下的超长超宽现浇隧道侧墙大体积混凝土温度及收缩裂缝问题,以太湖明挖现浇隧道为例,运用有限元软件结合二次开发,针对混凝土结构的里表温度场及中心拉应力进行参数化计算,系统性地研究了多种工况下的混凝土温度及应力演变规律,拟合了不同参数下的影响关系式,以期提出控裂指标进行现场应用。研究表明:模拟温度历程和实测温度历程较为一致;入模温度和养护温度分别提高12℃和20℃,温峰值分别增加6.8℃和12.4℃,最大里表温差分别增大5.5℃和下降7.5℃;拆模时间可控制在7 d左右;绝热温升上升40℃,自生变形减小400με,分段浇筑长度增大20 m,分层浇筑间隔时间延长50 d,中心最大拉应力分别增加2.039 MPa、2.228 MPa、0.950 MPa、1.691 MPa;利用有限元模拟进行参数化计算提出的现场控裂技术措施,有效地抑制了有害裂缝的产生,对指导后续大型隧道工程裂缝控制具有较高的现实意义。In order to solve the problem of temperature and shrinkage cracks of mass concrete in the side wall of ultra long and ultra wide cast-in-place tunnel based on the multi-field coupling mechanism,taking the Taihu open cut cast-in-place tunnel as an example,using finite element software and secondary development,parametric calculation is carried out for the inner surface temperature field and central tensile stress of the concrete structure,the evolution law of concrete temperature and stress under various working conditions is systematically studied,and the influence relationship under different parameters is fitted in order to propose crack control indicators for field application.The results show that:the simulated temperature history is consistent with the measured temperature history;the molding temperature and curing temperature increase by 12℃and 20℃respectively,the peak temperature increases by 6.8℃and 12.4℃respectively,and the maximum inner surface temperature difference increases by 5.5℃and decreases by 7.5℃respectively;the formwork removal time can be controlled at about 7 d;the adiabatic temperature rise rises by 40℃,the autogenous deformation decreases by 400με,the length of segmental pouring increases by 20 m,the interval of layered pouring extends by 50 d,and the maximum tensile stress in the center increases by 2.039 MPa,2.228 MPa,0.950 MPa and 1.691 MPa respectively;and,the on-site crack control technical measures proposed by using finite element simulation for parametric calculation effectively restrain the generation of harmful cracks,and have high practical significance for guiding the crack control of subsequent large-scale tunnel projects.

关 键 词：现浇隧道侧墙 超长超宽 有限元模拟 参数化分析 裂缝控制 

分 类 号：U454.18[建筑科学—桥梁与隧道工程]