摘要
为更好地再现地下金属矿深部采空区爆破扰动响应模型,将实测并去噪的爆破振动曲线作为动力加载,运用三维动力有限差分法,揭示围岩非线性演化特性并探讨采动顺序对其稳定性影响。动力扰动下,采空区顶、底板的最大、最小主应力明显大于其它部位,且出现拉应力;质点爆破振动监测时程曲线非线性特性强烈;垂直振动速度主要集中于采空区顶、底板,最大值25.2 cm/s。爆破瞬间,采空区东帮(先开挖侧)水平动位移值呈非线性上升,出现较大的动应力集中系数波动幅度和水平振动速度最大值(21.9 cm/s);塑性区也主要集中于东帮围岩且剪应变增量也相对较大。研究表明:采动顺序一定程度上影响了围岩稳定性,并且依据动力响应特性分析结果调整参数后的爆破设计有效控制了爆破边界,提高采场稳定性。
To reconstruct the response model of deep go＇of under blasting loads exactly,the three-dimensional dy- namic finite difference was used and dynamics load was entered as de-noised blasting vibration monitoring-curve. The nonlinear response time-space evolution characteristic of goaf surrounding rocks was revealed by response parameters and monitoring time-history curves. Under dynamic loading, the maximum principal stress in goaf roof and floor are bigger than others apparently and tensile stress appeared; the blasting vibration curves show obviously nonlinear characteristics and the big vertical vibrating velocity concentrating on the roof and floor and the maxima is 25.2 cm/s. The horizontal dynamic displacement on the east of goaf increased nonlinearly;the big fluctuation ampli- tude of dynamic stress concentration factor appears and the maximum vertical horizontal velocity is 21.9 cm/s; the plastic zone exists on the east side of surrounding rocks principally and shear strain increment there is also big. Result shows that the surrounding rock stability was influenced by mining sequence to some extent, and blasting design adjustment parameters based on response characteristics analysis controlled the blasting boundary effectively.
出处
《爆破》
CSCD
北大核心
2016年第3期10-16,共7页
Blasting
基金
国家自然科学基金资助(51274250)
国家"十二五"科技支撑计划项目资助(No.2012BAK09B02-05)
关键词
采空区围岩
动力扰动
非线性响应
演化特性
实测验证
goal surrounding rocks
dynamic disturbance
nonlinear response
time-space evolution
mmeasurement verification
