【摘要】 2010年8月13日四川绵竹市清平乡文家沟暴发特大规模泥石流灾害(简称"8.13"特大泥石流)。在野外调查的基础上,分析了此次泥石流灾害的特征,并从其形成条件入手,探讨了此次灾害的成因和未来发展趋势。文家沟流域在2010年8月12日16时至13日04时的降雨量达227 mm,暴雨形成强大洪水冲刷流域内在地震期间形成的滑坡-碎屑流堆积体,并形成高容重粘性泥石流。泥石流依次冲毁沟内19座谷坊和1座拦挡坝,冲出总量达429.3×104 m3,完全堵断绵远河,形成长约1 650 m、宽约420 m、高约12 m的堰塞坝,堰塞湖回水长1.5 km。泥石流共造成6人死亡或失踪,379间房屋被冲毁掩埋,汉(旺)清(平)公路中断,2座桥梁被毁。研究表明,松散物质的极大丰富和堵溃是导致"8.13"特大泥石流规模巨大的主要原因;文家沟在短期内泥石流仍会频发,但规模要比"8.13"泥石流小。更多还原

【Abstract】 On August 13,2010 an extra large debris flow occurred in Wenjia gully of Qingping township,Mianzhu,Sichuan province(hereinafter referred to as referred to as "8·13"debris flow).On the basis of field survey and analysis of the debris flow forming conditions,characteristics,causes and development tendencies of "8·13" debris flow are studied.The accumulated rainfall was 227 mm from 4:00 p.m.on August 12 to 04:00 on August 13th,2010 in Wenjia gully.The rainstorm caused a powerful flood that washed the deposits of landslides and debris-flows in Wenjia gully that induced by Wenchuan earthquake and a high density viscous debris-flow formed,finally.The debris flow destroyed all the 19 check dams and a debris dam,which had been planned to control debris flows in the gully.Total quantity of "8·13" debris flow reached to 429.3×104 m3,which completely blocked the Mianyuan River and formed a 1 650 m long,420 m wide and 12 m high barrier dam and a 1.5 km long dammed lake.The debris flow caused 5 people died and 1 people missing.379 buildings were destroyed by the debris flow and two bridges across the Mianyuan River were destroyed in Qingping Township and the highway connecting the two townships of Hanwang and Qingping was cut off.Researches show that abundance of loose materials and blockage are the main causes of extra large debris flow and debris flows would occur frequently in a short time in Wenjia Gully,but the sizes would be smaller than that of "8·13" debris flow.更多还原