Study On Catastrophe Evolution Mechanism Of Water Inrush In Deep Buried Tunnel Containing Filling Fault

Along with country strategy of the Belt and Road progressively puts into effect,opening up the construction of the cross-border and multi-modal transportationtraffic engineering is successively brought into schedule,making the scale of tunnelconstruction is increasingly extending, the geological conditionsin tunnel zone has also became more complicated,deep buried tunnel water inrushing disasters caused by filling type fault occur frequently. Therefore, researching different types offault structureleading to water inrushing disaster evolution characteristics, including different width of fault, different thicknesses of fault,different staggeredangles of fault,different staggered distances of fault,revealing water-inrush mechanism of underground construction and preventionhas very important meaning.The article takes deep buried tunnel containing filling fault as research objects,basing on the combining method of physical simulation and numerical simulation,carry out multiresponse parameter estimation of experimental researches on tunneling under high geostresses and high water pressure environment,analysis of the location,the scale,and the other factors of fault disastrous structures to the evolution of water inrushing of tunnel and providing certain reference for the related tunnel engineering construction.(1)A two-dimensional model test system for water inrush in deep buried tunnel containing filling fault was developed basing on the method similarity model test,its internal dimension size is 0.3m × 1.0m × 1.0m. Experimental system includes complete loading system, accurate data acquisition system and supporting auxiliary device. Fluid-solid coupling similar material is made up which is meeting the test requirements. To revealingcatastrophe evolution properties of water inrush in deep buried tunnel containing filling fault provide a new test equipment,test materials and test methods.(2)Relationship of pore water pressure,hydraulic gradient,the furthest dispersal distance and smallest safe thicknessof each model along with loading water pressure is obtained by different fault conditions of water bursting model simulations.Along with the increase of distance from the fault structure,the pore water pressure within model rock mass under different loading water pressure decreases gradually, and which conforms to the logarithmic function.Deducing the laws of the furthest dispersal distance and the minimum safe thickness by this,and the furthest dispersal distance and the minimum safe thickness increase gradually along with the increase of loading water pressure.(3)Physical test results were analyzed which found that the relative position of the same tunnel measuring point and the loading water pressure increases at the same range,the pore water pressure and the furthest dispersal distance were in positive correlation with width of fault,staggered angles of fault,staggered distances of fault.When the loading water pressure and the pore water pressures allowed by free surface at the same value, the minimum safe thickness was in positive correlation with width of fault and staggered distances of fault,and was in negative correlation with staggered angles of fault.(4)Numeral simulation software was used to extend the study onwhich the thickness of faultwas the impact on catastrophe evolution properties of water inrush in deep buried tunnel.When the loading water pressure increases within the same range and the measuring point at the same relative position,the growth amount of the pore water pressure increases along with the thickness of the fault decreases,the growth amount of the furthest dispersal distance increases along with the thickness of the fault decreases.When the loading water pressure and the pore water pressures allowed by free surface at the same value, the minimum safe thickness increases along with the thickness of the fault increases.(5)Making a systematic analysis on which the different conditions of fault is the effecton variation features of pore water pressure within prevention outburst rock mass,seepage laws of void water,the furthest dispersal distance and the minimum safe thickness basing on the summarizing and analyzing the test results, thus revealing catastrophe evolution mechanism of water inrush in deep buried tunnel under different width of fault,different thicknesses of fault, different staggered angles of fault, different staggered distances of fault.