Application and Parameterized Analysis of Temperature and Stress of Side Wall Concrete of Super long and Super wide Cast-in-situ Tunnel
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 400 με,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.
cast-in-situ tunnel side wallsuper long and super widefinite element simulationparametric analysiscrack control
万方数据
维普
