边坡加固锚索预应力变化规律分析

ANALYSIS ON PRESTRESS STATE OF CABLE APPLIED TO ROCK SLOPE REINFORCEMENT

目前,边坡预应力锚索加固技术已经得到广泛应用,但对锚索锁定后的预应力变化规律还缺乏系统深入的研究,特别是对破碎岩质边坡锚固后,锚索预应力的瞬时损失和长期稳定性还缺乏系统全面的认识。通过对工程边坡锚索预应力变化的系统监测和资料分析,探讨了锚索预应力的锁定损失、短期变化规律、长期变化规律和降雨对锚索有效预应力的影响,揭示了加固破碎岩质边坡的锚索预应力衰减变化的基本规律。

Although cable is widely used in slope engineering, the prestress change rules in cable are not studied thoroughly and systematically yet, especial the prestress loss after lock and the lasting prestress of cable in cracked rock slopes. Based on the systematical monitoring and analysis in a slope reinforcement project, the prestress loss after lock, short-term and long-term prestress change rules are studied, and also the influence of rainfall on the cable prestress state is monitored and discussed. It is found that the prestress loss after lock is largely based upon the shrink of the cable after lock, which is affected by friction to some degree. The short-term and long-term prestress loss is nonlinear, and the prestress loss can be divided into three stages. The influence of rain on the prestress loss should be considered. If the slope is not stable, the rain can affect the stabilization of the slope and then affect the prestress state of cable, otherwise, it has no influence on the prestress state.