Study On The Key Control Factors Of Mine Waste Debris Flows Initiation In Xiaoqinlin Gold Mine Area

The mine waste debris flow initiation mechanism is the hot spot and the advanced front question in debris flow forms study and the debris flow early warning now, studying on the key control factors which influence the mine waste debris flow initiation not only has the significance which push and consume debris flow form theory, but has the important guiding sense regarding the mine waste debris flow meteorology early warning's disaster prevention disaster reduction work.This thesis depends on the project named:"Shanxi Tongguan gold area environmental geology question special investigation" and "the Xiaoqinling gold area environmental geology survey and assessment" of the Xi'an center of CGS, the influence mine waste debris flow starts the thing source characteristic and the critical rainfall two key control factors have carried out the advanced investigation, analysis, test and some research work, has completed the waste residue source rock earthwork regulation parameter determination, the critical rainfall condition analysis systematically for the first time, proposed the research area gangue mud-rock flow starting pattern.The main achievement and the understanding include:(1) Accumulated a series of original data, including slag muck condition, grain composition, penetration coefficient, source volumeweight, factor of porosity, mudstone fluid volumeweight, shearing strength parameter and so on.(2) The waste slag muck characteristic includes:The slag muck piles are 5-15m high, sometimes individually reaches as high as 30m; The nature slope of reposes are between 30°and 45°; The non-protected slag muck accounts for 65%; The poor and extremely poor stability accounts for 76%; The 2/3 and absolutly blockages are account for 58.37%; The coarse particles content is big, P5 is 78.19%～91.38%; The factor of porosity is 34%～57% with good connectivity; The permeability is 0.094～0.127cm/s; According to above a new understanding that initiation is difficult under the ordinary rainfall condition.(3) Simulated has formed the critical raininess of gangue initiating. Obtains the critical raininess of the debris flows initiation is 67.14～134.29mm/h in Daxicha gully, that is encounters a-fifty-year or a-hundred-year rainstorm, there would be has about 50% solid particle to be at the critical initial condition. The research indicated that the pellet is thinner, the critical starting's raininess is smaller; The flood discharge blockage is more serious, the debris flow initial raininess would be smaller. It well explained the hardness initiation of the debris flows in the research area.(4) Proposed initial pattern of the min waste debris flow. Through the analysis on debris source characteristic and the rainfall intensity's influences, obtains the mine waste debris flow in the research area is rainstorm water-stone flow. Its two kinds of starting patterns are mainly includes "tarting in the gully type" and "the slope collapses-jamming-burst slippery type".