CAJ | 학술논문

现有的Hoek-Brown(HB)岩体地下开挖分析模型中，常将通用HB准则(2002版)的扰动因子D取为一固定值，与之不同之处在于将该因子从洞室开挖面至弹塑性分界面按渐进衰减考虑。结合非线性的非关联流动法则，给出了轴对称隧洞的临界支护压力、塑性区半径、应力和位移评价公式，相应的值可通过数值积分法获得。对节理岩体中洞室开挖爆破损伤和应力释放所致的渐变扰动分析，所提模型实质是对围岩塑性区软化问题的描述。算例表明，模型对D进行不同处理，也可得到轴对称隧洞理想塑性和弹脆塑性情况的分析解，为实际工程检验爆破开挖面附近岩体渐变扰动程度提供了理论解参考。
현유적Hoek-Brown(HB)암체지하개알분석모형중，상장통용HB준칙(2002판)적우동인자D취위일고정치，여지불동지처재우장해인자종동실개알면지탄소성분계면안점진쇠감고필。결합비선성적비관련류동법칙，급출료축대칭수동적림계지호압력、소성구반경、응력화위이평개공식，상응적치가통과수치적분법획득。대절리암체중동실개알폭파손상화응력석방소치적점변우동분석，소제모형실질시대위암소성구연화문제적묘술。산례표명，모형대D진행불동처리，야가득도축대칭수동이상소성화탄취소성정황적분석해，위실제공정검험폭파개알면부근암체점변우동정도제공료이론해삼고。
The disturbance factor in the generalized Hoek-Brown(HB) criterion (2002 edition),which is different from selection of a fixed value employed in the existing analysis for underground excavations in HB rock mass,is taken to be progressively decreased from the excavation surface to the elastic-plastic interface. By employing a non-linear non-associated flow rule,it can give a formulation of the critical internal pressure,the radius of plastic zone, stress and displacement,whose values can be determined by numerical integration techniques. The analysis model in this paper is the description of strain-softening in plastic zone for the progressive disturbance of the heavily jointed rock masses,which is triggered by blast damage and stress relaxation due to excavation. The calculation results of an example indicate that the present analysis model can also obtain analytical solutions of elastic-perfectly plastic and elastic-brittle-plastic models by means of different treatment forD,which provides a reference of theoretical solution for testing the degree of progressive disturbance near the excavation surface in practical project.