Sand is a typical particle structure. The effective stress and corresponding deformation are both determined by the particle characteristics of the medium skeleton

and the changeable condition of the particles will further affect the mechanical response of the earth pressure cell in the test process. To correctly measure the earth pressure value

micromechanical method was applied to analyse the force chain formed by the particles contact under loading unloading condition

and the transferring process

the force strain curve and relationship between the cell mechanical response and the ideal response curve were analyzed in detail

which verified the above mechanical response model based on Particle Flow Code (PFC) method. According to the structural characteristics of the sand and above numerical model

the loading condition

porosity

friction coefficient between the particles and stiffness of the earth pressure cell affecting mechanical response of the earth pressure cell were deeply investigated

the numerical results indicated that there were obvious hysteresis and strain irreversibility for the response curve

and the measured value was sensitive to the above factors. Therefore

research on the force chain structure and corresponding evolution law brings forward a scientific base and new research means for understanding its micromechanical characteristics

and different factors influencing the earth pressure cell are also important for cell calibration and practical monitoring to get more correct earth pressure value.