Abstract:In view of the problem of the challenges of excessive internal-external temperature differences,and significant cracking risks in flow-surface concrete of navigation-power hub projects during phased diversion construction caused by low-temperature river water cooling shock,an equivalent heat conduction model incorporating the negative heat source effect of cooling pipes is developed by integrating field monitoring data with three-dimensional finite element simulations.Adiabatic temperature rise inversion is employed to analyze temperature and stress fields under different temperature control strategies.An innovative multi-measure collaborative approach is proposed,combining mid-term cooling (target temperature:25 ℃),surface flow curing,and controlled pouring temperature (≤22 ℃),while quantifying the critical cooling rate threshold for crack prevention through sensitivity analysis.The results show that by normal temperature control measure,the internal along-river stress reaches 1.82 MPa (safety factor:1.27) and surface stress 1.46 MPa (safety factor:1.10),both violating anti-cracking specifications.Mid-term cooling combined with flow curing reduced surface stress to 0.46 MPa(safety factor:3.49).Introducing pouring temperature control further lowers the peak concrete temperature from 44.2 ℃ to 40.4 ℃,decreases internal stress to 1.45 MPa (safety factor:1.60),and increases the surface safety factor to 3.91.Sensitivity analysis reveals a critical cooling rate threshold of 1.0 ℃/d,exceeding this threshold caused the safetyfactor to plummet from 1.86 to 1.20.This paper establishes a systematic framework integrating thermodynamic parameter inversion,multi-field simulation,and multi-measure optimization,providing quantifiable design criteria for crack prevention in navigation-power hub projects.The proposed strategy enhances crack resistance significantly and improves structural durability.