横向锚固大试块岩体单轴压缩力学特性数值试验研究

锚固技术是岩土工程中的一个主要支护手段之一，如何揭示锚索（杆）与岩石的复合作用机制锚固和失效形态，越来越成为关注的焦点。采用FLAC数值方法，对大试块横向含锚岩体的单轴压缩条件下力学性态进行了试验研究，结果表明：锚索（杆）与围岩的复合增强机制不仅与外载的大小有关，而且与锚固界面的力学性质有很大关系。随着锚固界面凝聚力的减小，锚固界面和锚索轴向的应力值都将减少，即锚索（杆）增强承载能力下降。当凝聚力减小到一定数值时，锚索（杆）将脱黏而产生滑动，导致锚固失效，因此，提高锚固界面的黏结力是保证锚固效果的关键之一。大试块锚固体的实验室岩石力学试验无论是试块加工还是试验过程，将十分困难和繁琐。采用数值模拟方法代替实验室试验，具有省时、经济、可视性强等优点，是今后研究锚固体力学性态的重要途径，具有推广应用价值。

Numerical experiment for transverse anchoraged large rock specimen under the uniaxial compressive stress

Anchor reinforcement is one of the main support ways in rock engineering. How to bring out the composite reinforcing mechanism of cable to rock, as well as the invalidation mode of cable reinforcement is becoming a focus. By using the FLAC software, the transverse anchored large specimens numerical experiment under uniaxial compressive stress conditions has been done. It is shown that the cable composite reinforcing action for rock mass depends on not only the magnitude of compressive stress, but also the magnitude of cohesion on the bonding interface between rock and cable. As the decrease in cohesion on the bonding interface, the bonding interface stress and cable stress decrease correspondingly. After the cohesion on the bonding interface decreases to a certain magnitude, the cable will separate from the rock and the slide on interface will occur, i.e. the anchor reinforcement is invalid. So to enhance the cohesion on the bonding interface is an important measure for ensuring the anchor reinforcement valid. Besides, because it is difficult to manufacture the large anchored rock specimens and it is difficult to make mechanical experiments in laboratory, numerical simulation experiments have many advantages such as time-saving, economical and visua. So doing numerical simulations instead of making experiments in laboratory for anchored rock is a promising way in the future, it is valuable for generalization.