高寒地区抽水蓄能电站地下厂房施工期通风、保暖、散烟系统研究

以河北省丰宁抽水蓄能电站地下厂房施工为研究对象,根据各洞室贯通的先后顺序,将地下洞室群施工期的通风分为一期通风、二期通风、三期通风3个阶段,不同阶段设计不同的方案。研究设计出高寒地区冬季隧道内施工防寒保暖散烟系统,结合管道通风和自然通风的方式进行通风。现场应用效果明显,各掌子面及掘进施工断面粉尘和有害气体浓度在短时间内大幅度降低,施工断面通道附近粉尘浓度降低到10 mg/m3及以下的水平,通风洞主体通道粉尘浓度甚至降低到5 mg/m~3以下的水平。该技术实现了洞室群内施工周期各阶段风流的有序流动更新,降低了施工成本,保证了施工质量,创造了良好的施工环境,为同类型高寒地区水电站建设提供了经验参考。

Study on ventilation-thermal insulation-smoke dispersion system for construction period of pumped storage hydropower station in alpine region

By taking the construction of the underground powerhouse of Fengning Pumped Storage Hydropower Station as the study object, the ventilation during the construction period of the cavern group of the pumped storage hydropower station is divided into three phases, i.e. Phase I ventilation, Phase II ventilation and Phase III ventilation in accordance with the break-through order of all the caverns; for which different schemes are designed for different phases. A cold-proof-thermal insulation-smoke dispersion system for the construction in tunnel during winter within an alpine region is studied and designed; by which the ventilation is made with the mode of combining the duct ventilation with the natural ventilation. The in situ application effect is obvious: the concentrations of dusts and harmful gases at all the excavation faces and construction sections are largely lowered in a short period, i.e. the dust concentration near the passage of construction section is lowered below 10 mg/m3 and more, while the dust concentration incoming into the main passage of the ventilation adit is even lowered below 5 mg/m3 and more. Thus, the orderedly flowing and renewing of the air-flows in all the construction phases in the cavern group during the construction period are realized, and then the construction cost is lowered, the construction quality is ensured and a better construction environment is created as well. The study provides an experience reference for the construction of the similar hydropower station in alpine region.