Creep analysis and delay time of instability of ultrahigh pillar considering initial imperfections
FU Jianxin
CAO Shuai
SONG Weidong
TAN Yuye
Abstract：According to the ultrahigh pillar structure and mechanical characteristics,considering the initial geometric deviation caused by mining disturbance,the simplified model of the pressure bar was established.Based on elastic-plastic theory,the deflection and internal forces of ultrahigh pillar with initial geometric imperfections were analyzed and discussed.And based on the Kachanov theory of damage,the damage of ultrahigh pillar and damage failure time were analyzed.The results show that under the influence of the initial deflection,pillar will appear different degree of additional deflection,which grows with the increasing of initial deflection and pressure ratio.The start time of damage and instability of delay time of pillar has close relationship with initial deflection,pressure ratio and pmpressive strength.With the increase of pressure ratio and initial deflection,the damage in ubation time and the instability of delay time quickly become small,the greater the compressive strength,the greater the instability of the delay time,which means that the pillar is more stable.
Keywords：initial imperfectionultrahigh pillardamage creepinstability of delay timepressure bar
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：6( 279-284 )