青藏铁路沿线的大风特征及风压研究

Strong Wind and Wind Pressure along the Qinghai-Tibet Railway

选取青藏高原及周边66个气象站资料, 分析了青藏高原及青藏铁路沿线 1971—2000 年大风日数的空间分布特征及建站以来大风和风向特征, 计算了百年一遇的最大风速和风压. 分析发现: 青藏高原大风日数主要集中在青藏铁路沿线地区, 年际和年代际变化明显; 铁路沿线极端最大风速和历年平均最大风速都出现在铁路中部的托托河, 风向多为偏西风; 铁路沿线50 a、100 a一遇的10 min平均最大风速和风压都出现在安多地区. 以新疆达扳城为参考站, 推算出青藏铁路沿线各站的列车停驶临界风速. 为确保列车运营安全, 建议在昆仑山口至错那湖间的高山地段风口和列车转弯处建造防风设施.

Based on the data of 66 observatories in the Tibetan Plateau, the number of strong wind days from 1971 to 2000 in the plateau and that along the railway, spatial distribution of strong wind and the features of wind direction are analyzed. Meanwhile, The maximum wind velocities and maximum wind pressures with probabilities of 2% and 1% are calculated. It is found that the strong wind mainly occurs along the railway in the plateau, with distinct annual and decade variations. The supreme maximum wind velocity and the maximum annual mean wind velocity all occur at the central part of the railway, the Tuotuohe area, with prevailing west wind direction. Whereas, the maximum 10-min mean wind velocity and wind pressure with probabilities of 2% and 1% occur in Amdo County. The critical wind velocities for train operation at various stations along the railway are calculated referred to the observation at Dabancheng Station. To guarantee rail transportation safely, it is suggested that some windbreak establishments would be built at the wind eye areas between the Kunlun Mountain Pass and the Cona Lake, as well as the frequently turning rails.