By analyzing the effects of initial vertical geostress on plastic zone radius of circular underground tunnel,displacement changes in plastic and elastic zones of surrounding rock and bolt stress distribution mode,it is revealed that the initial vertical geostress is very important for reinforcement effect.

The relation among the coefficients , the vertical stress ratio (the ratio of the normal stress on the discontinuous plane to the uniaxial compression strength of the material), the undulation angle i and the shear area of the discontinuous plane are analysed.

By using IPC(Industrial Personal Computer),the vertical wheel contact force and the excited vibrant platform frequency are directly collected.

Experimental study on vertical stress of surrounding rock with equivalent material model;

It first calculates clay content,porosity,and acoustic velocity with relevant log data,and then calculates vertical effective stress by using Support Vector Machines for Regression and the overburden pressure with density log data,and finally calculate formation pore pressure by the effective pressure theore.

The variation of the factors that influence the test results as well as the declination of vertical effective stress with depth are analysed.

What deserves to be noticed is that declination of vertical effective stress in the e.