格库铁路青海段沙害成因及防沙措施

通过对格库(格尔木-库尔勒)铁路的调查发现,沿线主要存在沙埋路基、桥梁附近积沙和沙子进入道砟3种沙害形式。运用ANSYS/Fluent软件模拟路基和桥梁周围的流场结构,并根据沙害的严重程度建立了阻沙和固沙相结合的防沙体系。研究结果表明:路基和桥梁周围的气流场结构相似,都形成了迎风侧减速区、集流加速区、高速区、低速区和速度恢复区,不同点是桥梁周围形成了2个集流加速区和高速区;积沙都是发生在风速降低的地方;路基背风侧坡脚积沙最多,桥梁积沙主要位于桥梁的迎风侧和背风侧,桥梁下积沙较少;道床背风侧积沙多于迎风侧,道床内轨枕积沙沿着主导风向呈现出逐渐增多的趋势。最后对现场建立的防沙体系的工作原理进行了分析。

Causes of Sand Damage and Its Control Measures in Qinghai Section of Golmud-Korla Railway

Through investigations along the Golmud-Korla Railway,it is found that there are mainly three types of sand damages such as sand-buried subgrade,sand accumulation near the bridge and sand entering into the ballast.ANSYS/Fluent was used to analyze the f low f ield structures of subgrade and bridge,and sand control system of anti-sand and stabilization of sand was built according to the severity of sand damage.The research results show that the airf low f ield structures around the subgrade and the bridge are similar.Five velocity zones are formed which are windward side deceleration zone,air uplift acceleration zone,high speed zone,low speed zone and speed recovery zone.The difference is that two air uplift acceleration zones and a high speed zone are formed around the bridge.Sand accumulation occurs in the place where wind speed is reduced.For subgrade,the leeward slope foot has the most sand accumulation.For bridge,sand accumulation is mainly located at the windward and leeward sides,and there is less sand under the bridge.For track bed,sand accumulation at the leeward side is more signif icant than at the windward side,and sand accumulation around sleeper on track bed gradually increases along the dominant wind direction.Finally,the working principle of the sand control system established on site was analyzed.