CAJ | 학술논문

通过对2011年7月3日的茂县棉簇沟泥石流灾害的现场调查,从物源、地形和水源条件入手,分析了灾害特征与形成演化过程.强降雨是本次泥石流的诱发因素,沟道内复杂的地形地貌特征为泥石流提供了演化和规模放大条件:(1)泥石流导致堰塞湖溃决,为泥石流提供了近1×104m3的水源,增强了泥石流的水动力条件,增加了沿途冲刷量;(2)沟道内多处基岩卡口和跌水放大了本次泥石流的规模和速度;(3)沿途固体物质补给使泥石流容重逐步增大.此次泥石流造成沟道微地貌改变,今后泥石流暴发的可能性和频率将会大大增加,高频率、中小规模泥石流将是今后该沟泥石流活动的特征.
통과대2011년7월3일적무현면족구니석류재해적현장조사,종물원、지형화수원조건입수,분석료재해특정여형성연화과정.강강우시본차니석류적유발인소,구도내복잡적지형지모특정위니석류제공료연화화규모방대조건:(1)니석류도치언새호궤결,위니석류제공료근1×104m3적수원,증강료니석류적수동력조건,증가료연도충쇄량;(2)구도내다처기암잡구화질수방대료본차니석류적규모화속도;(3)연도고체물질보급사니석류용중축보증대.차차니석류조성구도미지모개변,금후니석류폭발적가능성화빈솔장회대대증가,고빈솔、중소규모니석류장시금후해구니석류활동적특정.
The formation and evolvement process of this debris flow was analyzed based on the field investi?gation on the material sources, rainfall, and topography conditions. The rainfall was the inducing factor;however, the topography in the gully was the main reason which causes this catastrophic debris flow:(1) the dammed lakes formed in the earthquake were broken which increased the water supply, strengthened the dynamic force,and aggravated the erosion quantity finally. (2) the narrow sections and the drops ampli?fied the peak flow and velocity of the debris flow in the gully. (3) the solid material supplies the debris flow and enlarged the density along the gully. The possibility and frequency of debris flow will be much higher in heavy rainfalls in the future, but the scale will be less than this giant debris flow because of the microtopography had been changing. Suggestions were proposed:the warning system, control engineering should be built and disaster prevention and reduction awareness of local people also should be improved.