Method for calculating thickness of loosening circle of tunnel surrounding rock

The invention relates to a method for calculating the thickness of a loosening circle of a tunnel surrounding rock. By the introduction of the concept of a broken rock integrity coefficient Rv and a loosening circle integrity coefficient Lv, the broken state of rock mass in a loosening circle of the surrounding rock is quantified. A quantitatively defined value of the thickness of the loosening circle is obtained by an indoor test of the rock. Then, the thickness of the loosening circle of the surrounding rock is judged by combining acoustic method field test conditions. The invention is based on the forming principle and nature of the loosening circle, a judgment standard formulated by this method is objective and real, and the method has universality and generalization. 本发明涉及的隧道围岩松动圈厚度计算方法。通过引入破碎岩石完整性系数R和松动圈完整性系数L的概念，对围岩松动圈的岩体破碎状态量化。利用岩石的室内试验得出松动圈厚度的量化界定值，然后结合声波法现场测试情况，判断出围岩松动圈的厚度。本发明从松动圈的形成原理与本质上出发，以此方法所制定的判别标准客观、真实，具有普遍性与推广性。