【摘要】 青海省玉树州结古镇北山的5条泥石流沟曾在2003-07发生过群发式泥石流灾害。强烈地震发生后的5～10a是泥石流的高发期。2010-04-14(简称"4.14")玉树地震使结古镇周围山体出现大量崩塌、滑坡,为后期群发式泥石流灾害发育提供了丰富的固体物源。根据国务院划定的结古镇地震灾害重建规划范围及野外考察资料,在GIS环境下,采用对泥石流运动方程进行求解,并结合泥石流运动过程中的地形、坡度、沟道、流量过程、含沙量等信息,对结古镇重建区范围内的17条沟进行了泥石流运动-淤积过程数值模拟。对模拟结果的分析表明,结古镇灾后重建区受泥石流威胁极大,泥石流到达结古镇后,其最大流速、泥深及能量仍具有较大破坏性;对现有老城区威胁严重的泥石流沟是结古陇巴和德念陇巴,对规划新区具有严重威胁的泥石流沟是热翁陇、上尖果陇、下尖果陇以及显子陇,扎曲河部分河段有被泥石流堵断的危险。建议在重建规划中对泥石流沟进行工程治理,保障"新玉树,新结古"灾后重建的安全。更多还原

【Abstract】 The first 5 to 10 years or so after a strong earthquake have a high dangerous degree for occurring debris flow in the epicenter area.There have 5 debris flow gullies which happened group-occurring debris flow disaster in the north hillside of Jiegu township in the July 29th,2003.The earthquake of Ms7.1 occurred in 14th of April,2010 near Yushu produces a lot of landslide and rockfall near Jiegu town,which provides a rich loose material for the possibility of debris flow hazard in future.According to the scope of planning and reconstruction designated by the State Council and field survey data,17 debris flow gullies threaten to Jiegu town are identified.Numeric simulation model for Kinematics-siltation is used to simulate the group-occurring 17 gullies in GIS environment,combining with its developing conditions such as terrain,slope,channel,discharge,sediment content.The motion equation for debris flow is solved.Results of simulation show well consistent with the actual movement and deposition distribution of debris flow gullies which indicate the accuracy of the model and numeric simulation.The analysis results also show that the debris flow post a great threaten to the post-disaster reconstruction of Jiegu town,for debris flow reaches even at the end of town,its maximum velocity,flow depth and energy still has great destructive.Two serious debris flow gullies frighten to the build-up area of Jiegu town are identified as Jiegulongba gully and Denianlongba gully.At the same time,more debris flow gullies which serious threatening to the new reconstruction planning area are located in the study area which are Reweng gully Shangjianguo gully,Xiajianguo gully and Xianzi gully.Part segments of the main river of Zaqu have the risk of blocked by debris flow.It is proposed that engineering control measurement for those gullies should be carried out,as to guarantee the safety of post-earthquake reconstructing for the expectation of "New Yushu,New Jiegu".更多还原