基于环向应力岩爆判据的不同级别岩爆区分布的数值模拟研究

为了避免莫尔-库仑和虎克-布朗屈服准则各自的缺陷,采用C＋＋语言对FLAC进行了二次开发,将它们复合在一起,提出了一种弹-脆-塑性的本构模型。采用徐林生及Russense判据（环向应力与单轴抗压强度之比）作为岩爆判据,研究了在不同围压条件下,圆形洞室开挖之后围岩再次平衡时已发生的各种级别岩爆区的分布规律,对严重、中等及...

Numerical Simulation of the Distribution of Rockburst Regions with Different Magnitudes Based on Loop Stress Criteria

Mohr-Coulomb and Hoek-Brown yielding criteria in FLAC are compounded to overcome their drawbacks using C++. An elastic-brittle-plastic constitutive model is proposed. Two kinds of rockburst criteria proposed by Xu et al and Russense, respectively, are used to assess the distribution of rockburst regions in the circular tunnel surrounding rock at different confining pressures after the excavated surrounding rock enters an equilibrium state again. In two rockburst criteria, the ratio of loop stress to uniaxial compressive strength is used to determine the magnitudes of rockbursts, such as serious, moderate and slight rockbursts. The relation between these three kinds of rockbursts is discussed. Detailed analyses are carried out to find the difference and agreement between the present numerical results and observations in situ. As the confining pressure increases, the elements having occurred rockbursts of different magnitudes increase; moreover, the number of rockburst elements increases, and they migrate toward the depth of the surrounding rock.