CAJ | 학술논문

为了解围岩流变条件下锚杆应力变化规律,在求出西原模型下圆形巷道的黏弹塑性位移解的基础上,运用"中性点"理论,推导出全长锚固锚杆剪应力与轴应力随时间变化的表达式.据现场围岩位移数据,反推出西元模型中的4个参量值.计算结果表明:中性点的位置与时间无关;当围岩处于减速蠕变时,锚杆的应力增加速率减速趋零;当围岩处于等速蠕变阶段,锚杆的应力增加速率随着时间推移减速趋稳.为验证锚杆在巷道服务年限内是否失效与确定二次支护时间提供一种新的思路.
위료해위암류변조건하묘간응력변화규률,재구출서원모형하원형항도적점탄소성위이해적기출상,운용"중성점"이론,추도출전장묘고묘간전응력여축응력수시간변화적표체식.거현장위암위이수거,반추출서원모형중적4개삼량치.계산결과표명:중성점적위치여시간무관;당위암처우감속연변시,묘간적응력증가속솔감속추령;당위암처우등속연변계단,묘간적응력증가속솔수착시간추이감속추은.위험증묘간재항도복무년한내시부실효여학정이차지호시간제공일충신적사로.
In order to explore the stress distribution of bolt based on rheological conditions, at first, the visco-elastic plastic displacement solution of circular roadway under the condition of visco-elastoplastic model has been obtained, and then the expressions of bolt shear and axial stress of full-length anchoring bolt have been deduced by using "neutral point" theory. According to the site surrounding rock dis-placement data, four parameters value in visco-elastoplastic model has been derived reversely. The re-sults show that the position of neutral point has nothing to do with time. When the rock is in the decel-erating creep stage, the rate of increasing stress of bolt decreases and reduces to zero gradually. When the rock is in the steady creep stage, the rate of increasing stress of bolt decreases and reduces to a fixed value with the passage of time. This paper has provided a new way to verify whether the bolt is failure or not in roadway service life and to confirm secondary support time.