City flood disaster scenario simulation based on 1D-2D coupled
rain-flood model: A case study in Luoyang, China.
In order to realize the reproduction and simulation of urban rainstorm
and waterlogging scenarios with complex underlying surfaces. Based on
the Mike series models, we constructed an urban storm-flood coupling
model considering one-dimensional river channels, two-dimensional ground
and underground pipe networks. Luoyang City was used as a pilot to
realize the construction of a one-dimensional and two-dimensional
coupled urban flood model and flood simulation. where is located in the
western part of Henan Province, China. The coupled model was calibrated
and verified by the submerged water depths of 16 survey points in two
historical storms flood events. The average relative error of the
calibration simulated water depth was 22.65%, and the average absolute
error was 13.93cm; the average relative error of the verified simulated
water depth was 15.27%, The average absolute error is 7.54cm, and the
simulation result is good. Finally, 28 rains with different return
periods and different durations were designed to simulate and analyze
the rainstorm inundation in the downtown area of Luoyang. The result
shows that the R2 of rainfall and urban rainstorm inundation is 0.8776,
and the R2 of rainfall duration and urban rainstorm inundation is
0.8141. Therefore, rainfall is the decisive factor in the formation of
urban waterlogging disasters, which is actually the rainfall duration.
The study results have important practical significance for urban flood
prevention, disaster reduction and traffic emergency management.