Analysis And Safety Evaluation Of Force Characteristic Ma Ya Zi Different Levels Of Tunnel Surrounding Rock Structure

The article is based on Mayazi tunnel to mainly study on the force characteristics oftunnel structure and safety evaluation in III, IV, V grade rock.Firstly,we are aware of all levels of rock by geological prediction site and geologicalsketch, and while successfully forecast the lots fault fracture zone,and gushing geologicaldisasters which are inâ…¤ level rock. The introduction is given which is about BQ rockclassification in Specification. Then the method can principally obtain uniaxial compressivestrength of saturated RC and the integrity coefficient of the rock, KV. The article determinesof uniaxial compressive with on-site laboratory strength, and the number of joints by statisticson the tunnel faces protruding parts. It can make us distinguish between different levels ofrock quickly and accurately and adjust the parameters of excavation and support in time.Secondly, to test on surrounding convergence and vault sink about every5section in III,IV, V grade rock,it is obtained that: the higher the rock level, the greater the deformationvalues, the convergence time relates to lithology, joints and other factors. According theultimate value of the displacement and the displacement rate, it can be made a judgment onthe surrounding rock deformation to determine the safety of the tunnel. To derive the rockmechanics parameters with reverse displacement analysis based on monitoring andmeasurement, combining rock parameters which are given in design specification; it can makesure that the finite element simulation uses the rock parameters.Furthermore, to measure the stress of the rock and the structure through the pressure cell,steel gauge, strain gauge, concrete surface strain gauges and other test components buried inIV, V-class rock Lot, to analyze the test data and compare the results, it can ensure the loadsharing proportion between the tunnel early branch and the lining, the variation of the Internalforce of the tunnel lining and the force status to find out that the weak parts of tunnel stress.Simultaneously, combining with monitoring and measurement, it can be made judgmentabout the supporting time. The comparisons about load sharing proportion are shown whichare between V-class rock and the early support, the early support and the complex archsupport, the complex arch support and the lining. Finally, receiving the factors by combing with the reverse displacement method,normalizing these parameters of all the levels of the rock, simulating the structure and thesurrounding rock with Finite element software, we can obtain displacement cloud and stresscloud to analyze the deformation trend, so that we can check if the vault subsidence values,the convergence value of the surrounding, and bolt axis sought are in keeping with the resultof the field test. It can be receive that the proportion between the convergences value of thesurrounding and the vault subsidence values, which are caused by all levels of the rock indifferent construction methods. Then it can find out the most unfavorable process during thetunnel excavation. With the lining axial force, moment,bolt axial force, the early support shear,the safety factor of the lining interface can be derived to evaluate the safety of the tunnel.