基于能量耗散过程的拦砂坝泄流孔堵塞判别研究

Blocking Judgment of Check Dam Discharging Orifices based on Energy Dissipation Process

泄流孔堵塞对坝体结构稳定和长期安全运行有着极大的影响。现拦砂坝泄流孔的设计大多基于经验,缺乏定量分析方法。基于泥石流在泄流孔中的能量耗散过程,提出了基于获取必要参数情况下的泄流孔堵塞判识方法,分析了泄流孔设计参数和泥石流性质对堵塞的影响。进一步通过对比验证了判别方法的合理性,可将误差控制在15%以内。最后应用该法对四川省绵竹市文家沟的拦砂坝泄流孔进行了分析,结果表明该坝泄流孔较易发生充满全孔的泥石流停淤堵塞,与实地勘察结果一致。根据理论分析,为保证泥石流的顺畅排导,建议在该坝前布设能量调控设施,调控进入泄流孔的泥石流流速使其控制在合理范围内。

The blocking of discharging orifices has a large influence on the stability of dam structures and long-term safe operation.The design of discharging orifices of sand bars is mostly based on experience and lacks a quantitative analysis method.By analyzing the energy dissipation process of debris flows in the spillway hole,a method based on the acquisition of necessary parameters is proposed for determining the clogging of discharging orifices,and the influence of the design parameters of the discharging orifices and the clogging of debris flows property is analyzed.The rationality of the discrimination method is further verified by controlling the error within 15%.Finally,using this method to analyze the discharging orifice of the Wenjiagou check dam in Mianzhu city,Sichuan Province.The results show that the discharging orifices of the Wenjiagou dam are more likely to be filled with debris flows,which is consistent with the field investigation results.According to the theoretical analysis,it is suggested to install energy control facilities in front of the dam.Regulate and control the flow rate of debris flows into the discharging orifice within a reasonable range,so as to ensure the smooth discharge of debris flow.