巷道围岩松动圈支护理论

ROADWAY SUPPORT THEORY BASED ON BROKEN ROCK ZONE

基于多年对围岩松动圈的研究成果，本文提出并论述了松动圈支护理论、松动圈围岩分类方法和锚喷支护机理三个问题。现场实践和实验室研究表明：地应力与围岩的相互作用会产生大小不同的围岩松动圈；松动圈扩展过程中产生的碎胀力及其所造成的有害变形是巷道支护的主要对象；松动圈尺寸越大，巷道收敛变形也越大，支护越困难。而在现场条件下，支护对松动圈的影响并不明显，因此，取松动圈尺寸作为围岩分类指标是科学的、合理的，已经大量实践所证实。松动圈尺寸不同，锚喷的作用机理也不同，因而应采用不同的设计方法。本文建议加强岩石碎胀力的研究，即重视岩石破坏后性质的研究工作。

Based on many years research of broken rock zone the paper describes roadway support theory, classification of rocks in the loose rock zone and mechanism of rock-bolting and shotcreting. Field and lab tests show that interaction between rocks and earth pressure produce different size of broken rock zone; that the bulking force resulted from expansion of the broken zone and thus caused deformation is the major objective of roadway support; and that the larger the extent of broken rock zone, the greater the roadway convergence, and it is more difficult to support.However, the effect of broken zone on the support is not obvious in site, a and therefore the size of broken rock zone is used as an index for classification of the surrounding rock, and it is scientific and rational. This was proved to be correct by field practice. The mechanism of rock-bolting and shotcreting changes with the size of broken rock zone,therefore,the design of support should be changed accordingly. It is suggested to investigate further the bulking force of rock-breaking, that is, attention should be attached to post-failure nature of rocks.