基于微震能量演化的大岗山右岸边坡抗剪洞加固效果研究

发布时间：2018-11-06 11:52

【摘要】：微震监测技术在岩体工程监测中获得了广泛的应用,但如何依据微震监测数据来评价岩体工程的稳定性,至今还存在很多问题。以大岗山右岸边坡工程为研究背景,基于定量微震学原理,采用微震能量密度来综合反映岩体微破裂分布特征,并在理论上推导微震能量频度关系,提出以b_ε值来表征岩体微破裂变形程度,进一步研究了该边坡抗剪洞加固前后边坡岩体微震能量转移特征、震源机制、变形特性及其稳定性演化规律。研究结果表明,微震能量密度可以帮助识别边坡潜在危险区域,能量频度关系中的b_ε值的变化揭示了边坡微破裂与变形的演化过程;抗剪洞加固后边坡微震事件活动率和能量密度均明显降低,边坡受力性能明显改善;边坡开挖期间抗剪洞加固区岩体微震的b_ε值小幅降低,并在抗剪洞加固后有所增加,表明抗剪洞抑制了岩体微破裂及变形,提高了边坡稳定性。通过对比工程现场变形监测结果,验证了方法的可靠性。提出的微震能量密度及能量频度关系相结合的评价方法,丰富了工程岩体稳定性微震分析方法,可为类似岩质边坡加固措施的选择及稳定性分析提供参考。
[Abstract]:Microseismic monitoring technology has been widely used in rock mass engineering monitoring, but there are still many problems on how to evaluate the stability of rock mass engineering based on microseismic monitoring data. Based on the principle of quantitative microseismology, the microseismic energy density is used to comprehensively reflect the microfracture distribution characteristics of rock mass, and the relationship of microseismic energy and frequency is deduced theoretically with the right bank slope engineering of Dagangshan as the research background, based on the principle of quantitative microseismology. The b- 蔚 value is proposed to characterize the degree of micro-fracture deformation of rock mass, and the energy transfer characteristics, focal mechanism, deformation characteristics and stability evolution of rock mass in the slope before and after the reinforcement of the shear tunnel are further studied. The results show that the microseismic energy density can help to identify the potential dangerous area of slope, and the change of b- 蔚 value in the relation of energy and frequency reveals the evolution process of microfracture and deformation of slope. The activity rate and energy density of the microseismic events of the slope are obviously reduced and the mechanical performance of the slope is obviously improved after the reinforcement of the shear tunnel. During the excavation of the slope, the b蔚 value of the rock mass in the area strengthened by shear tunnel decreases slightly, and increases after the reinforcement of the anti-shear hole, which indicates that the anti-shear tunnel can restrain the micro-fracture and deformation of the rock mass and improve the stability of the slope. The reliability of the method is verified by comparing the results of field deformation monitoring. The method of evaluating microseismic energy density and energy frequency is put forward, which enriches the microseismic analysis method of engineering rock mass stability, and can provide a reference for the selection of reinforcement measures and stability analysis of similar rock slope.
【作者单位】：大连理工大学海岸和近海工程国家重点实验室;大连理工大学岩石破裂与失稳研究中心;力软科技(大连)股份有限公司;
【基金】：国家重点基础研究发展计划(“973”计划)项目(2014CB047100) 国家自然科学基金项目(51274053)
【分类号】：TU457

【相似文献】