| Due to years of use and operation, varieties of security issues, such as lack of the crestelevation of dikes, low flood prevention standards, serious leveeslope seepage, aging dischargestructures and insufficient building intensity, which all cause latent danger to safe operation ofreservoirs, happen to part of reservoirs in China, especially medium and small reservoirs. Tofurther improve the engineering system and enhance regulation and storage capacity to waterresources, it is necessary to implement reinforcement schemes to dangerous reservoirs.For dangerous reservoirs, there probably comes out kinds of problems to hydraulic structuressuch as dykes, spillways and flood discharging tunnels,for the reason that reinforcementschemes are implemented on the original basis such that transform designs are faced with manyconstraints, consequently, existing the hydraulic characteristics of the hydraulic structures. Thispaper applies the method of numerical simulation and model test to study hydraulic characteristicof each dangerous reservoir, which will be conducted reinforcement tasks to.（1）Focusing on seepage of one specific plain reservoir, research is conducted on seepagestate and seepage stability of the dam. Afterwards, effect on the two reinforcement schemes, i.e.high-pressure jet grouting cut-off wall to serious seepage part of the dam, are assessed.（2）With the application of numerical simulation and model test, for new-built spillways in aspecific dangerous reservoir that will be conducted reinforcement schemes to, considering thecharacteristics of the studied spillway, i.e. complex flow phenomena of chute section locating inthe bend section, the flow velocity and relatively large water lateral slope and the flow instabilityat the end of the chute, some research work is done on hydraulic characteristics, includingdischarge, velocity, water surface profile, flow pattern, etc. Afterwards, this paper proposesoptimization measure to the horizontal slope of tail-weir of the upstream stilling pool and that ofthe chute bottom plate, according to which, the hydraulic characteristics of the entire chute and thesmooth downstream flow can be guaranteed.（3）With the combined application of physical models and numerical simulation,considering insufficient discharge, cavitation and erosion caused by bad flow pattern and depositat the inlet in the original flood discharging tunnel, this paper mainly conducts research onhydraulic characteristics, including discharge capacity, flow pattern, energy dissipation effect andminimum water level for operation, along the adjusted flood discharging tunnel in the form of Ski-jump‘. The study shows good flow characteristics over the integral adjusted flood dischargingtunnel, with only partial improvement. |
PDF Full Text Request